diff mbox series

[6/7] mmc: Implement content of UHS-II card initialization functions

Message ID 20211203105103.11306-7-jasonlai.genesyslogic@gmail.com (mailing list archive)
State New, archived
Headers show
Series Preparations to support SD UHS-II cards | expand

Commit Message

Lai Jason Dec. 3, 2021, 10:51 a.m. UTC
From: Jason Lai <jason.lai@genesyslogic.com.tw>

UHS-II card initialization flow is divided into 2 categories: PHY & Card.
Part 1 - PHY Initialization:
         Every host controller may need their own avtivation operation
         to establish LINK between controller and card. So we add a new
         member function(uhs2_detect_init) in struct mmc_host_ops for host
         controller use.
Part 2 - Card Initialization:
         This part can be divided into 6 substeps.
         1. Send UHS-II CCMD DEVICE_INIT to card.
         2. Send UHS-II CCMD ENUMERATE to card.
         3. Send UHS-II Native Read CCMD to obtain capabilities in CFG_REG
            of card.
         4. Host compares capabilities of host controller and  card,
            then write the negotiated values to Setting field in CFG_REG
            of card through UHS-II Native Write CCMD.
         5. Switch host controller's clock to Range B if it is supported
            by both host controller and card.
         6. Execute legacy SD initialization flow.
Part 3 - Provide a function to tranaform legacy SD command packet into
         UHS-II SD-TRAN DCMD packet.

Most of the code added above came from Intel's original patch[1].

[1]
https://patchwork.kernel.org/project/linux-mmc/patch/1419672479-30852-2-
git-send-email-yi.y.sun@intel.com/

Signed-off-by: Jason Lai <jason.lai@genesyslogic.com.tw>
---
 drivers/mmc/core/sd_uhs2.c | 831 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 810 insertions(+), 21 deletions(-)

Comments

Ulf Hansson Dec. 14, 2021, 8:28 p.m. UTC | #1
On Fri, 3 Dec 2021 at 11:51, Jason Lai <jasonlai.genesyslogic@gmail.com> wrote:
>
> From: Jason Lai <jason.lai@genesyslogic.com.tw>
>
> UHS-II card initialization flow is divided into 2 categories: PHY & Card.
> Part 1 - PHY Initialization:
>          Every host controller may need their own avtivation operation
>          to establish LINK between controller and card. So we add a new
>          member function(uhs2_detect_init) in struct mmc_host_ops for host
>          controller use.
> Part 2 - Card Initialization:
>          This part can be divided into 6 substeps.
>          1. Send UHS-II CCMD DEVICE_INIT to card.
>          2. Send UHS-II CCMD ENUMERATE to card.
>          3. Send UHS-II Native Read CCMD to obtain capabilities in CFG_REG
>             of card.
>          4. Host compares capabilities of host controller and  card,
>             then write the negotiated values to Setting field in CFG_REG
>             of card through UHS-II Native Write CCMD.
>          5. Switch host controller's clock to Range B if it is supported
>             by both host controller and card.
>          6. Execute legacy SD initialization flow.
> Part 3 - Provide a function to tranaform legacy SD command packet into
>          UHS-II SD-TRAN DCMD packet.
>
> Most of the code added above came from Intel's original patch[1].
>
> [1]
> https://patchwork.kernel.org/project/linux-mmc/patch/1419672479-30852-2-
> git-send-email-yi.y.sun@intel.com/
>
> Signed-off-by: Jason Lai <jason.lai@genesyslogic.com.tw>
> ---
>  drivers/mmc/core/sd_uhs2.c | 831 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 810 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/mmc/core/sd_uhs2.c b/drivers/mmc/core/sd_uhs2.c
> index 24aa51a6d..d13283d54 100644
> --- a/drivers/mmc/core/sd_uhs2.c
> +++ b/drivers/mmc/core/sd_uhs2.c
> @@ -3,6 +3,7 @@
>   * Copyright (C) 2021 Linaro Ltd
>   *
>   * Author: Ulf Hansson <ulf.hansson@linaro.org>
> + * Author: Jason Lai <jason.lai@genesyslogic.com.tw>
>   *
>   * Support for SD UHS-II cards
>   */
> @@ -10,29 +11,31 @@
>
>  #include <linux/mmc/host.h>
>  #include <linux/mmc/card.h>
> +#include <linux/mmc/sd_uhs2.h>
>
>  #include "core.h"
>  #include "bus.h"
>  #include "sd.h"
>  #include "mmc_ops.h"
> +#include "sd_uhs2.h"
>
>  static const unsigned int sd_uhs2_freqs[] = { 52000000, 26000000 };
>
> -static int sd_uhs2_set_ios(struct mmc_host *host)
> +static void sd_uhs2_set_ios(struct mmc_host *host)

Please don't change the function to return void. It's better to allow
the callback to return an error code, even if that might not be of
benefit for your particular host variant.

>  {
>         struct mmc_ios *ios = &host->ios;
>
> -       return host->ops->uhs2_set_ios(host, ios);
> +       host->ops->set_ios(host, ios);
>  }
>
> -static int sd_uhs2_power_up(struct mmc_host *host)
> +static void sd_uhs2_power_up(struct mmc_host *host)
>  {

Ditto.

>         host->ios.vdd = fls(host->ocr_avail) - 1;
>         host->ios.clock = host->f_init;
>         host->ios.timing = MMC_TIMING_SD_UHS2;
>         host->ios.power_mode = MMC_POWER_UP;
>
> -       return sd_uhs2_set_ios(host);
> +       sd_uhs2_set_ios(host);
>  }
>
>  static void sd_uhs2_power_off(struct mmc_host *host)
> @@ -45,6 +48,50 @@ static void sd_uhs2_power_off(struct mmc_host *host)
>         sd_uhs2_set_ios(host);
>  }
>
> +/**
> + * sd_uhs2_cmd_assemble() - build up UHS-II command packet which is embeded in
> + *                          mmc_command structure
> + * @cmd:       MMC command to executed
> + * @uhs2_cmd:  UHS2 command corresponded to MMC command
> + * @header:    Header field of UHS-II command cxpacket
> + * @arg:       Argument field of UHS-II command packet
> + * @payload:   Payload field of UHS-II command packet
> + * @plen:      Payload length
> + * @resp:      Response buffer is allocated by caller and it is used to keep
> + *              the response of CM-TRAN command. For SD-TRAN command, uhs2_resp
> + *              should be null and SD-TRAN command response should be stored in
> + *              resp of mmc_command.
> + * @resp_len:  Response buffer length
> + *
> + * Different from legacy SD command, there defined several types of packets
> + * in UHS-II, which include CM-TRAN and SD-TRAN. These packets are then
> + * transformed to differential signals and transmitted/received between
> + * transceiver and receiver.
> + *
> + * The UHS-II packet structure(uhs2_cmd) are added in structure mmc_command
> + * and be filled according to the inputed parameters provided by caller.
> + *
> + * For mmc requests, call this function before issuing command to SD card.
> + * Host controller specific request function will send packet in uhs2_cmd
> + * to UHS-II SD card.
> + *

I think we discussed the above functions description earlier. The
above description is just way too overwhelming. What the function does
is that fills out the uhs2_cmd data structure, that's it.

As this is a static function, I wouldn't mind that you simply drop the
entire function description above. Or try to make the description
short and clear.

> + */
> +static void sd_uhs2_cmd_assemble(struct mmc_command *cmd,
> +                             struct uhs2_command *uhs2_cmd,
> +                             u16 header, u16 arg,
> +                             u32 *payload, u8 plen, u8 *resp, u8 resp_len)
> +{
> +       uhs2_cmd->header = header;
> +       uhs2_cmd->arg = arg;
> +       uhs2_cmd->payload = payload;
> +       uhs2_cmd->payload_len = plen * sizeof(u32);
> +       uhs2_cmd->packet_len = uhs2_cmd->payload_len + 4;
> +
> +       cmd->uhs2_cmd = uhs2_cmd;
> +       cmd->uhs2_resp = resp;
> +       cmd->uhs2_resp_len = resp_len;
> +}
> +
>  /*
>   * Run the phy initialization sequence, which mainly relies on the UHS-II host
>   * to check that we reach the expected electrical state, between the host and
> @@ -52,16 +99,98 @@ static void sd_uhs2_power_off(struct mmc_host *host)
>   */
>  static int sd_uhs2_phy_init(struct mmc_host *host)
>  {
> -       return 0;
> +       int err = 0;
> +
> +       /*
> +        * Every host controller can assign its own function which is used
> +        * to initialize PHY.
> +        */
> +       err = host->ops->uhs2_detect_init(host)

It looks like you didn't declare this callback as part of the struct
mmc_host_ops, so this does not even compile. Please fix that.

I also suggest moving the above comment into the header file along
with its declaration, as it's usually where we keep this information.
Moreover, to make it clear what the callback is intended for, I
suggest renaming it to "uhs2_phy_init".

> +       if (err) {
> +               pr_err("%s: fail to detect UHS2!\n", mmc_hostname(host));

Maybe "failed to initial phy for UHS-II", is better?

> +       }
> +
> +       return err;
>  }
>
>  /*
> - * Do the early initialization of the card, by sending the device init
> -roadcast
> + * Do the early initialization of the card, by sending the device init broadcast

Looks like you are correcting a spelling mistake, which is good.
However, please make this a part of the patch that introduced this,
earlier in the series.

>   * command and wait for the process to be completed.
>   */
>  static int sd_uhs2_dev_init(struct mmc_host *host)
>  {
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u32 cnt;
> +       u32 dap, gap, resp_gap;
> +       u16 header = 0, arg = 0;
> +       u32 payload[1];
> +       u8 plen = 1;
> +       u8 gd = 0, cf = 1;
> +       u8 resp[6] = {0};
> +       u8 resp_len = 6;
> +       int err;
> +
> +       dap = host->uhs2_caps.dap;
> +       gap = host->uhs2_caps.gap;
> +
> +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
> +       arg = ((UHS2_DEV_CMD_DEVICE_INIT & 0xFF) << 8) |
> +              UHS2_NATIVE_CMD_WRITE |
> +              UHS2_NATIVE_CMD_PLEN_4B |
> +              (UHS2_DEV_CMD_DEVICE_INIT >> 8);
> +
> +       /*
> +        * Refer to UHS-II Addendum Version 1.02 section 6.3.1.
> +        * Max. time from DEVICE_INIT CCMD EOP reception on Device
> +        * Rx to its SOP transmission on Device Tx(Tfwd_init_cmd) is
> +        * 1 second.
> +        */
> +       cmd.busy_timeout = 1000;
> +
> +       /*
> +        * Refer to UHS-II Addendum Version 1.02 section 6.2.6.3.
> +        * When the number of the DEVICE_INIT commands is reach to
> +        * 30 tiems, Host shall stop issuing DEVICE_INIT command
> +        * and regard it as an error.
> +        */
> +       for (cnt = 0; cnt < 30; cnt++) {
> +               payload[0] = ((dap & 0xF) << 12) |
> +                            (cf << 11)         |
> +                            ((gd & 0xF) << 4)  |
> +                            (gap & 0xF);
> +
> +               sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
> +                                 payload, plen, resp, resp_len);
> +
> +               err = mmc_wait_for_cmd(host, &cmd, 0);
> +
> +               if (err) {
> +                       pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                              mmc_hostname(host), __func__, err);
> +                       return -EIO;
> +               }
> +
> +               if (resp[3] != (UHS2_DEV_CMD_DEVICE_INIT & 0xFF)) {
> +                       pr_err("%s: DEVICE_INIT response is wrong!\n",
> +                              mmc_hostname(host));
> +                       return -EIO;
> +               }
> +
> +               if (resp[5] & 0x8) {
> +                       host->group_desc = gd;
> +                       break;
> +               }
> +               resp_gap = resp[4] & 0x0F;
> +               if (gap == resp_gap)
> +                       gd++;
> +       }
> +       if (cnt == 30) {
> +               pr_err("%s: DEVICE_INIT fail, already 30 times!\n",
> +                      mmc_hostname(host));
> +               return -EIO;
> +       }
> +
>         return 0;
>  }
>
> @@ -72,32 +201,519 @@ static int sd_uhs2_dev_init(struct mmc_host *host)
>   */
>  static int sd_uhs2_enum(struct mmc_host *host, u32 *node_id)
>  {
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u16 header = 0, arg = 0;
> +       u32 payload[1];
> +       u8 plen = 1;
> +       u8 id_f = 0xF, id_l = 0x0;
> +       u8 resp[8] = {0};
> +       u8 resp_len = 8;
> +       int err;
> +
> +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
> +       arg = ((UHS2_DEV_CMD_ENUMERATE & 0xFF) << 8) |
> +              UHS2_NATIVE_CMD_WRITE |
> +              UHS2_NATIVE_CMD_PLEN_4B |
> +              (UHS2_DEV_CMD_ENUMERATE >> 8);
> +
> +       payload[0] = (id_f << 4) | id_l;
> +
> +       sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> +                         resp, resp_len);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       if (resp[3] != (UHS2_DEV_CMD_ENUMERATE & 0xFF)) {
> +               pr_err("%s: ENUMERATE response is wrong!\n",
> +                      mmc_hostname(host));
> +               return -EIO;
> +       }
> +
> +       id_f = (resp[4] >> 4) & 0xF;
> +       id_l = resp[4] & 0xF;
> +       *node_id = id_f;
> +
>         return 0;
>  }
>
>  /*
>   * Read the UHS-II configuration registers (CFG_REG) of the card, by sending it
>   * commands and by parsing the responses. Store a copy of the relevant data in
> - * card->uhs2_config.
> + * host->uhs2_card_prop.

This isn't correct. The code below is storing the configuration in
card->uhs2_config, which is the correct thing to do.

>   */
>  static int sd_uhs2_config_read(struct mmc_host *host, struct mmc_card *card)
>  {
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u16 header = 0, arg = 0;
> +       u32 cap;
> +       int err;
> +
> +       header = UHS2_NATIVE_PACKET |
> +                UHS2_PACKET_TYPE_CCMD |
> +                card->uhs2_config.node_id;
> +       arg = ((UHS2_DEV_CONFIG_GEN_CAPS & 0xFF) << 8) |
> +              UHS2_NATIVE_CMD_READ |
> +              UHS2_NATIVE_CMD_PLEN_4B |
> +              (UHS2_DEV_CONFIG_GEN_CAPS >> 8);
> +
> +       /* There is no payload because per spec, there should be
> +        * no payload field for read CCMD.
> +        * Plen is set in arg. Per spec, plen for read CCMD
> +        * represents the len of read data which is assigned in payload
> +        * of following RES (p136).
> +        */
> +       sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return err;
> +       }
> +
> +       cap = cmd.resp[0];
> +       card->uhs2_config.n_lanes =
> +                               (cap >> UHS2_DEV_CONFIG_N_LANES_POS) &
> +                               UHS2_DEV_CONFIG_N_LANES_MASK;
> +       card->uhs2_config.dadr_len =
> +                               (cap >> UHS2_DEV_CONFIG_DADR_POS) &
> +                               UHS2_DEV_CONFIG_DADR_MASK;
> +       card->uhs2_config.app_type =
> +                               (cap >> UHS2_DEV_CONFIG_APP_POS) &
> +                               UHS2_DEV_CONFIG_APP_MASK;
> +
> +       arg = ((UHS2_DEV_CONFIG_PHY_CAPS & 0xFF) << 8) |
> +              UHS2_NATIVE_CMD_READ |
> +              UHS2_NATIVE_CMD_PLEN_8B |
> +             (UHS2_DEV_CONFIG_PHY_CAPS >> 8);
> +
> +       sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       cap = cmd.resp[0];
> +       card->uhs2_config.phy_minor_rev =
> +                               cap & UHS2_DEV_CONFIG_PHY_MINOR_MASK;
> +       card->uhs2_config.phy_major_rev =
> +                               (cap >> UHS2_DEV_CONFIG_PHY_MAJOR_POS) &
> +                                UHS2_DEV_CONFIG_PHY_MAJOR_MASK;
> +       card->uhs2_config.can_hibernate =
> +                               (cap >> UHS2_DEV_CONFIG_CAN_HIBER_POS) &
> +                                UHS2_DEV_CONFIG_CAN_HIBER_MASK;
> +
> +       cap = cmd.resp[1];
> +       card->uhs2_config.n_lss_sync =
> +                               cap & UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
> +       card->uhs2_config.n_lss_dir =
> +                               (cap >> UHS2_DEV_CONFIG_N_LSS_DIR_POS) &
> +                               UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> +       if (card->uhs2_config.n_lss_sync == 0)
> +               card->uhs2_config.n_lss_sync = 16 << 2;
> +       else
> +               card->uhs2_config.n_lss_sync <<= 2;
> +
> +       if (card->uhs2_config.n_lss_dir == 0)
> +               card->uhs2_config.n_lss_dir = 16 << 3;
> +       else
> +               card->uhs2_config.n_lss_dir <<= 3;
> +
> +       arg = ((UHS2_DEV_CONFIG_LINK_TRAN_CAPS & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_READ |
> +               UHS2_NATIVE_CMD_PLEN_8B |
> +               (UHS2_DEV_CONFIG_LINK_TRAN_CAPS >> 8);
> +
> +       sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       cap = cmd.resp[0];
> +       card->uhs2_config.link_minor_rev =
> +                               cap & UHS2_DEV_CONFIG_LT_MINOR_MASK;
> +       card->uhs2_config.link_major_rev =
> +                               (cap >> UHS2_DEV_CONFIG_LT_MAJOR_POS) &
> +                               UHS2_DEV_CONFIG_LT_MAJOR_MASK;
> +       card->uhs2_config.n_fcu =
> +                               (cap >> UHS2_DEV_CONFIG_N_FCU_POS) &
> +                               UHS2_DEV_CONFIG_N_FCU_MASK;
> +       card->uhs2_config.dev_type =
> +                               (cap >>UHS2_DEV_CONFIG_DEV_TYPE_POS) &
> +                               UHS2_DEV_CONFIG_DEV_TYPE_MASK;
> +       card->uhs2_config.maxblk_len =
> +                               (cap >>UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) &
> +                               UHS2_DEV_CONFIG_MAX_BLK_LEN_MASK;
> +
> +       cap = cmd.resp[1];
> +       card->uhs2_config.n_data_gap =
> +                               cap & UHS2_DEV_CONFIG_N_DATA_GAP_MASK;
> +       if (card->uhs2_config.n_fcu == 0)
> +               card->uhs2_config.n_fcu = 256;
> +
>         return 0;
>  }
>
> -/*
> +/**
>   * Based on the card's and host's UHS-II capabilities, let's update the
>   * configuration of the card and the host. This may also include to move to a
>   * greater speed range/mode. Depending on the updated configuration, we may
> -eed
> - * to do a soft reset of the card via sending it a GO_DORMANT_STATE command.
> + * need to do a soft reset of the card via sending it a GO_DORMANT_STATE
> + * command.
>   *
>   * In the final step, let's check if the card signals "config completion",
> -hich
> - * indicates that the card has moved from config state into active state.
> + * which indicates that the card has moved from config state into active state.

As I said earlier, please fix spelling mistakes as part of the
patch(es) that introduced them.

>   */
>  static int sd_uhs2_config_write(struct mmc_host *host, struct mmc_card *card)
>  {
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u16 header = 0, arg = 0;
> +       u32 payload[2];
> +       u8 nMinDataGap;
> +       u8 plen;
> +       u8 try;
> +       int err;
> +       u8 resp[5] = {0};
> +       u8 resp_len = 5;
> +
> +       header = UHS2_NATIVE_PACKET |
> +                UHS2_PACKET_TYPE_CCMD | card->uhs2_config.node_id;
> +       arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> +              UHS2_NATIVE_CMD_WRITE |
> +              UHS2_NATIVE_CMD_PLEN_8B |
> +              (UHS2_DEV_CONFIG_GEN_SET >> 8);
> +
> +       if (card->uhs2_config.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD &&
> +           host->uhs2_caps.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD) {
> +               /* Support HD */
> +               host->flags |= MMC_UHS2_2L_HD;
> +               nMinDataGap = 1;
> +       } else {
> +               /* Only support 2L-FD so far */
> +               host->flags &= ~MMC_UHS2_2L_HD;
> +               nMinDataGap = 3;
> +       }
> +
> +       /*
> +        * Most UHS-II cards only support FD and 2L-HD mode. Other lane numbers
> +        * defined in UHS-II addendem Ver1.01 are optional.
> +        */
> +       host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> +       card->uhs2_config.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> +
> +       plen = 2;
> +       payload[0] = card->uhs2_config.n_lanes_set <<
> +                    UHS2_DEV_CONFIG_N_LANES_POS;
> +       payload[1] = 0;
> +       payload[0] = cpu_to_be32(payload[0]);
> +       payload[1] = cpu_to_be32(payload[1]);
> +
> +       /*
> +        * There is no payload because per spec, there should be
> +        * no payload field for read CCMD.
> +        * Plen is set in arg. Per spec, plen for read CCMD
> +        * represents the len of read data which is assigned in payload
> +        * of following RES (p136).
> +        */
> +       sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> +                         NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       arg = ((UHS2_DEV_CONFIG_PHY_SET & 0xFF) << 8) |
> +              UHS2_NATIVE_CMD_WRITE |
> +              UHS2_NATIVE_CMD_PLEN_8B |
> +              (UHS2_DEV_CONFIG_PHY_SET >> 8);
> +
> +       for (try = 0; try < 2; try++) {

This loop looks a bit odd. Perhaps you can explain why we need this
with a comment in the code?

Optionally, we could potentially also try to move some part of it into
a separate helper function and then just call that from here instead?
In this way, we may be able to avoid the loop altogether and thus also
the code should become more readable. What do you think?

> +               plen = 2;
> +
> +               if (host->uhs2_caps.speed_range ==
> +                       UHS2_DEV_CONFIG_PHY_SET_SPEED_B) {
> +                       host->flags |= MMC_UHS2_SPEED_B;
> +                       card->uhs2_config.speed_range_set =
> +                                       UHS2_DEV_CONFIG_PHY_SET_SPEED_B;
> +               } else {
> +                       card->uhs2_config.speed_range_set =
> +                                       UHS2_DEV_CONFIG_PHY_SET_SPEED_A;
> +                       host->flags &= ~MMC_UHS2_SPEED_B;
> +               }
> +
> +               payload[0] = card->uhs2_config.speed_range_set <<
> +                                       UHS2_DEV_CONFIG_PHY_SET_SPEED_POS;
> +
> +               card->uhs2_config.n_lss_sync_set =
> +                       (min(card->uhs2_config.n_lss_sync,
> +                            host->uhs2_caps.n_lss_sync) >> 2) &
> +                       UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
> +               host->uhs2_caps.n_lss_sync_set =
> +                       card->uhs2_config.n_lss_sync_set;
> +
> +               if (try == 0) {
> +                       host->uhs2_caps.n_lss_dir_set =
> +                               (card->uhs2_config.n_lss_dir >> 3) &
> +                               UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> +                       card->uhs2_config.n_lss_dir_set =
> +                               ((host->uhs2_caps.n_lss_dir >> 3) + 1) &
> +                               UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> +               } else {
> +                       card->uhs2_config.n_lss_dir_set =
> +                               (max(card->uhs2_config.n_lss_dir,
> +                                    host->uhs2_caps.n_lss_dir) >> 3) &
> +                               UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
> +                       host->uhs2_caps.n_lss_dir_set =
> +                               card->uhs2_config.n_lss_dir_set;
> +               }
> +
> +               payload[1] = (card->uhs2_config.n_lss_dir_set <<
> +                                       UHS2_DEV_CONFIG_N_LSS_DIR_POS) |
> +                            card->uhs2_config.n_lss_sync_set;
> +               payload[0] = cpu_to_be32(payload[0]);
> +               payload[1] = cpu_to_be32(payload[1]);
> +
> +               resp_len = 4;
> +               memset(resp, 0, sizeof(resp));
> +
> +               sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
> +                                 payload, plen, resp, resp_len);
> +
> +               err = mmc_wait_for_cmd(host, &cmd, 0);
> +               if (err) {
> +                       pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                              mmc_hostname(host), __func__, err);
> +                       return -EIO;
> +               }
> +
> +               if (!(resp[2] & 0x80))
> +                       break;
> +       }
> +
> +       arg = ((UHS2_DEV_CONFIG_LINK_TRAN_SET & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_WRITE |
> +               UHS2_NATIVE_CMD_PLEN_8B |
> +               (UHS2_DEV_CONFIG_LINK_TRAN_SET >> 8);
> +
> +       plen = 2;
> +
> +       if (card->uhs2_config.app_type == UHS2_DEV_CONFIG_APP_SD_MEM)
> +               card->uhs2_config.maxblk_len_set =
> +                       UHS2_DEV_CONFIG_LT_SET_MAX_BLK_LEN;
> +       else
> +               card->uhs2_config.maxblk_len_set =
> +                       min(card->uhs2_config.maxblk_len,
> +                           host->uhs2_caps.maxblk_len);
> +       host->uhs2_caps.maxblk_len_set =
> +                       card->uhs2_config.maxblk_len_set;
> +
> +       card->uhs2_config.n_fcu_set =
> +                       min(card->uhs2_config.n_fcu,
> +                           host->uhs2_caps.n_fcu);
> +       host->uhs2_caps.n_fcu_set = card->uhs2_config.n_fcu_set;
> +
> +       card->uhs2_config.n_data_gap_set =
> +                       max(nMinDataGap, card->uhs2_config.n_data_gap);
> +       host->uhs2_caps.n_data_gap_set =
> +                       card->uhs2_config.n_data_gap_set;
> +
> +       host->uhs2_caps.max_retry_set = 3;
> +       card->uhs2_config.max_retry_set = host->uhs2_caps.max_retry_set;
> +
> +       payload[0] = (card->uhs2_config.maxblk_len_set <<
> +                                       UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) |
> +                    (card->uhs2_config.max_retry_set <<
> +                                       UHS2_DEV_CONFIG_LT_SET_MAX_RETRY_POS) |
> +                    (card->uhs2_config.n_fcu_set <<
> +                                       UHS2_DEV_CONFIG_N_FCU_POS);
> +       payload[1] = card->uhs2_config.n_data_gap_set;
> +       payload[0] = cpu_to_be32(payload[0]);
> +       payload[1] = cpu_to_be32(payload[1]);
> +
> +       sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> +                         NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                       mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> +              UHS2_NATIVE_CMD_WRITE |
> +              UHS2_NATIVE_CMD_PLEN_8B |
> +              (UHS2_DEV_CONFIG_GEN_SET >> 8);
> +
> +       plen = 2;
> +       payload[0] = 0;
> +       payload[1] = UHS2_DEV_CONFIG_GEN_SET_CFG_COMPLETE;
> +       payload[0] = cpu_to_be32(payload[0]);
> +       payload[1] = cpu_to_be32(payload[1]);
> +
> +       resp_len = 5;
> +       memset(resp, 0, sizeof(resp));
> +       sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> +                         resp, resp_len);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       /* Set host Config Setting registers */
> +       if (!host->ops->uhs2_set_reg ||

Again, I couldn't find this callback being declared, so I guess this
doesn't compile. Please fix that.

I agree that the callback should not be optional. However, I think
this is far too late in the initialization process to check it. This
can be checked already when adding the host in mmc_add_host(), in case
the host supports UHS-II, for example.

Moreover, I am questioning the name of the callback. It seems like we
are going to use it for various UHS-II operations. The name
"uhs2_set_reg" doesn't really explain this. Maybe "uhs2_do_action", or
if you can come up with something even better, that would be great.

> +           host->ops->uhs2_set_reg(host, SET_CONFIG)) {
> +               pr_err("%s: %s: UHS2 SET_CONFIG fail!\n",
> +                       mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       return 0;
> +}
> +
> +static int sd_uhs2_go_dormant(struct mmc_host *host, bool hibernate, u32 node_id)
> +{
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u16 header = 0, arg = 0;
> +       u32 payload[1];
> +       u8 plen = 1;
> +       int err;
> +
> +       /* Disable Normal INT */
> +       if (!host->ops->uhs2_set_reg ||
> +           host->ops->uhs2_set_reg(host, DISABLE_INT)) {
> +               pr_err("%s: %s: UHS2 DISABLE_INT fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD | node_id;
> +
> +       arg = ((UHS2_DEV_CMD_GO_DORMANT_STATE & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_WRITE |
> +               UHS2_NATIVE_CMD_PLEN_4B |
> +               (UHS2_DEV_CMD_GO_DORMANT_STATE >> 8);
> +
> +       if (hibernate)
> +               payload[0] = UHS2_DEV_CMD_DORMANT_HIBER;
> +
> +       sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> +                         NULL, 0);
> +
> +       err = mmc_wait_for_cmd(host, &cmd, 0);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       /* Check Dormant State in Present */
> +       if (!host->ops->uhs2_set_reg ||
> +           host->ops->uhs2_set_reg(host, CHECK_DORMANT)) {
> +               pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       if (host->ops->uhs2_disable_clk)

Again, another callback that lacks declaration.

> +               host->ops->uhs2_disable_clk(host);

In fact, rather than adding another callback, we could make use of the
"->uhs2_set_reg" callback?

Or, another option would be to use the ->uhs2_set_ios(). That would be
similar to what we do for legacy SD cards with the ->set_ios()
callback.

For example, we can do like this:
host->ios.power_mode = MMC_POWER_ON;
host->ios.clock = 0;
host->ops->uhs2_set_ios(host, &host->ios);

What do you think? Maybe we need a separate host->ios_uhs2 for this too?

> +
> +       return 0;
> +}
> +
> +static int sd_uhs2_change_speed(struct mmc_host *host, u32 node_id)
> +{
> +       struct mmc_command cmd = {0};
> +       struct uhs2_command uhs2_cmd = {};
> +       u16 header = 0, arg = 0;
> +       int err;
> +       int timeout = 100;
> +
> +       /* Change Speed Range at controller side. */
> +       if (!host->ops->uhs2_set_reg ||
> +           host->ops->uhs2_set_reg(host, SET_SPEED_B)) {
> +               pr_err("%s: %s: UHS2 SET_SPEED fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       err = sd_uhs2_go_dormant(host, false, node_id);
> +       if (err) {
> +               pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail, err= 0x%x!\n",
> +                      mmc_hostname(host), __func__, err);
> +               return -EIO;
> +       }
> +
> +       /* restore sd clock */
> +       mmc_delay(5);
> +       if (host->ops->uhs2_enable_clk)
> +               host->ops->uhs2_enable_clk(host);

Ditto.

> +
> +       /* Enable Normal INT */
> +       if (!host->ops->uhs2_set_reg ||
> +           host->ops->uhs2_set_reg(host, ENABLE_INT)) {
> +               pr_err("%s: %s: UHS2 ENABLE_INT fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return -EIO;
> +       }
> +
> +       /*
> +        * According to UHS-II Addendum Version 1.01, chapter 6.2.3, wait card
> +        * switch to Active State
> +        */
> +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD |
> +                host->card->uhs2_config.node_id;

Didn't you pass node_id as an in-parameter? Why can't you use that?

> +       arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> +               UHS2_NATIVE_CMD_READ |
> +               UHS2_NATIVE_CMD_PLEN_8B |
> +               (UHS2_DEV_CONFIG_GEN_SET >> 8);
> +       do {
> +               sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd,
> +                                 header, arg,
> +                                 NULL, 0,
> +                                 NULL, 0);
> +               err = mmc_wait_for_cmd(host, &cmd, 0);
> +               if (err) {
> +                       pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> +                              mmc_hostname(host), __func__, err);
> +                       return -EIO;
> +               }
> +
> +               if (cmd.resp[1] & UHS2_DEV_CONFIG_GEN_SET_CFG_COMPLETE)
> +                       break;
> +
> +               timeout--;
> +               if (timeout == 0) {
> +                       pr_err("%s: %s: Not switch to Active in 100 ms\n",
> +                              mmc_hostname(host->mmc), __func__);
> +                       return -EIO;
> +               }
> +
> +               mmc_delay(1);
> +       } while (1);
> +
>         return 0;
>  }
>
> @@ -108,8 +724,70 @@ static int sd_uhs2_config_write(struct mmc_host *host, struct mmc_card *card)
>   * be set through a legacy CMD6. Note that, the power limit that becomes set,
>   * survives a soft reset through the GO_DORMANT_STATE command.
>   */
> -static int sd_uhs2_legacy_init(struct mmc_host *host, struct mmc_card *card)
> +static int sd_uhs2_legacy_init(struct mmc_host *host)

Please make this change from the patch that introduced this code.

>  {
> +       int err;
> +       u32 ocr, rocr;
> +
> +       WARN_ON(!host->claimed);
> +
> +       /* Send CMD0 to reset SD card */
> +       mmc_go_idle(host);
> +
> +       /* Send CMD8 to communicate SD interface operation condition */
> +       err = mmc_send_if_cond(host, host->ocr_avail);
> +       if (err) {
> +               pr_err("%s: %s: SEND_IF_COND fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return err;
> +       }
> +
> +       /*
> +        * Send host capacity support information and activate card's
> +        * initialization process.
> +        */
> +       err = mmc_send_app_op_cond(host, 0, &ocr);
> +       if (err) {
> +               pr_err("%s: %s: SD_SEND_OP_COND fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return err;
> +       }
> +
> +       if (host->ocr_avail_sd)
> +               host->ocr_avail = host->ocr_avail_sd;

Please drop this part. I don't want to encourage host's to use
ocr_avail_sd (for reasons that we can discuss another time).

If we need something specific for UHS-II, then it's better to add that.

> +
> +       /*
> +        * Some SD cards claims an out of spec VDD voltage range. Let's treat
> +        * these bits as being in-valid and especially also bit7.
> +        */
> +       ocr &= ~0x7FFF;
> +       rocr = mmc_select_voltage(host, ocr);
> +
> +       /*
> +        * Some cards have zero value of rocr in UHS-II mode. Assign host's
> +        * ocr value to rocr.
> +        */
> +       if (!rocr) {
> +               if (host->ocr_avail) {
> +                       rocr = host->ocr_avail;
> +               } else {
> +                       pr_err("%s: %s: there is no valid OCR.\n",
> +                              mmc_hostname(host), __func__);
> +                       return -EINVAL;
> +               }
> +       }
> +
> +       /*
> +        * Get CID, send relative address, get CSD are the same as legacy
> +        * sd, call mmc_sd_init_card() in sd.c directly
> +        */
> +       err = mmc_sd_init_card(host, rocr, NULL);
> +       if (err) {
> +               pr_err("%s: %s: mmc_sd_init_card() fail!\n",
> +                      mmc_hostname(host), __func__);
> +               return err;
> +       }

So this means we will start using the host callbacks for the legacy SD
interface, like ->set_ios() for example.

In other words, data in host->ios.* seems to be used, both for UHS-II
and legacy SD. That can be messy for host drivers to manage, I think.
Maybe we should add a separate host->ios_uhs2.*, that we use solely
for UHS2 instead?

There is also another problem here. mmc_sd_init_card() will allocate a
new struct mmc_card and assign it to host->card, if it succeeds with
initialization.

By looking at the changes below, it looks like you will assign
host->card, with the struct mmc_card that we have allocated for UHS-II
in sd_uhs2_init_card(), prior to calling sd_uhs2_legacy_init(). Not
only will this lead to a memory leak, but more importantly we will
lose all the information that we have parsed/stored from the card for
UHS-II, right?

Don't we need to keep the UHS-II information of the card around? Or is
it okay to throw it away after initialization?

What am I missing?

> +
>         return 0;
>  }
>
> @@ -124,12 +802,16 @@ static int sd_uhs2_init_card(struct mmc_host *host)
>         int err;
>
>         err = sd_uhs2_dev_init(host);
> -       if (err)
> +       if (err) {
> +               pr_err("%s: UHS2 DEVICE_INIT fail!\n", mmc_hostname(host));
>                 return err;
> +       }
>
>         err = sd_uhs2_enum(host, &node_id);
> -       if (err)
> +       if (err) {
> +               pr_err("%s: UHS2 ENUMERATE fail!\n", mmc_hostname(host));
>                 return err;
> +       }
>
>         card = mmc_alloc_card(host, &sd_type);
>         if (IS_ERR(card))
> @@ -142,15 +824,26 @@ static int sd_uhs2_init_card(struct mmc_host *host)
>         if (err)
>                 goto err;
>
> +       /* Change to Speed Range B if it is supported */
> +       if (host->flags & MMC_UHS2_SPEED_B) {

I noticed that you have added the "host->flags", to keep track of
UHS-II states and some UHS-II capabilities of the host. I would rather
see that UHS-II host capabilities should be part of the
host->uhs2_caps.*.

When it comes to keeping track of UHS-II states, like when we want to
move to a new speed mode for example, that may be better to keep as a
part of a new host->ios_uhs2.*, as I kind of indicated above.

> +               err = sd_uhs2_change_speed(host, node_id);
> +               if (err) {
> +                       pr_err("%s: %s: UHS2 sd_uhs2_change_speed() fail!\n",
> +                               mmc_hostname(host), __func__);
> +                       return err;
> +               }
> +       }
> +
>         err = sd_uhs2_config_write(host, card);
>         if (err)
>                 goto err;
>
> -       err = sd_uhs2_legacy_init(host, card);
> +       host->card = card;
> +
> +       err = sd_uhs2_legacy_init(host);
>         if (err)
>                 goto err;
>
> -       host->card = card;

This is the part that will lead to the memory leak of a struct mmc_card.

>         return 0;
>
>  err:
> @@ -217,6 +910,78 @@ static int sd_uhs2_hw_reset(struct mmc_host *host)
>         return 0;
>  }

[...]

I have stopped the review at this point, let's see if we can conclude
on the way forward around my comments on the parts above, to start
with.

Kind regards
Uffe
Lai Jason Jan. 6, 2022, 10:31 a.m. UTC | #2
On Wed, Dec 15, 2021 at 4:29 AM Ulf Hansson <ulf.hansson@linaro.org> wrote:
>
>> On Fri, 3 Dec 2021 at 11:51, Jason Lai <jasonlai.genesyslogic@gmail.com> wrote:
> >
> > From: Jason Lai <jason.lai@genesyslogic.com.tw>
> >
> > UHS-II card initialization flow is divided into 2 categories: PHY & Card.
> > Part 1 - PHY Initialization:
> >          Every host controller may need their own avtivation operation
> >          to establish LINK between controller and card. So we add a new
> >          member function(uhs2_detect_init) in struct mmc_host_ops for host
> >          controller use.
> > Part 2 - Card Initialization:
> >          This part can be divided into 6 substeps.
> >          1. Send UHS-II CCMD DEVICE_INIT to card.
> >          2. Send UHS-II CCMD ENUMERATE to card.
> >          3. Send UHS-II Native Read CCMD to obtain capabilities in CFG_REG
> >             of card.
> >          4. Host compares capabilities of host controller and  card,
> >             then write the negotiated values to Setting field in CFG_REG
> >             of card through UHS-II Native Write CCMD.
> >          5. Switch host controller's clock to Range B if it is supported
> >             by both host controller and card.
> >          6. Execute legacy SD initialization flow.
> > Part 3 - Provide a function to tranaform legacy SD command packet into
> >          UHS-II SD-TRAN DCMD packet.
> >
> > Most of the code added above came from Intel's original patch[1].
> >
> > [1]
> > https://patchwork.kernel.org/project/linux-mmc/patch/1419672479-30852-2-
> > git-send-email-yi.y.sun@intel.com/
> >
> > Signed-off-by: Jason Lai <jason.lai@genesyslogic.com.tw>
> > ---
> >  drivers/mmc/core/sd_uhs2.c | 831 ++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 810 insertions(+), 21 deletions(-)
> >
> > diff --git a/drivers/mmc/core/sd_uhs2.c b/drivers/mmc/core/sd_uhs2.c
> > index 24aa51a6d..d13283d54 100644
> > --- a/drivers/mmc/core/sd_uhs2.c
> > +++ b/drivers/mmc/core/sd_uhs2.c
> > @@ -3,6 +3,7 @@
> >
> >  static const unsigned int sd_uhs2_freqs[] = { 52000000, 26000000 };
> >
> > -static int sd_uhs2_set_ios(struct mmc_host *host)
> > +static void sd_uhs2_set_ios(struct mmc_host *host)
>
> Please don't change the function to return void. It's better to allow
> the callback to return an error code, even if that might not be of
> benefit for your particular host variant.

I have a question about the return type of this function. In
sd_uhs2_set_ios(), we only called
host->ops->set_ios() and the return type of that function was VOID. So
is there a reason
that this function must has a non-void return type?

> >  {
> >         struct mmc_ios *ios = &host->ios;
> >
> > -       return host->ops->uhs2_set_ios(host, ios);
> > +       host->ops->set_ios(host, ios);
> >  }
> >
> > -static int sd_uhs2_power_up(struct mmc_host *host)
> > +static void sd_uhs2_power_up(struct mmc_host *host)
> >  {
>
> Ditto.
>
> >         host->ios.vdd = fls(host->ocr_avail) - 1;
> >         host->ios.clock = host->f_init;
> >         host->ios.timing = MMC_TIMING_SD_UHS2;
> >         host->ios.power_mode = MMC_POWER_UP;
> >
> > -       return sd_uhs2_set_ios(host);
> > +       sd_uhs2_set_ios(host);
> >  }
> >
> >  static void sd_uhs2_power_off(struct mmc_host *host)
> > @@ -45,6 +48,50 @@ static void sd_uhs2_power_off(struct mmc_host *host)
> >         sd_uhs2_set_ios(host);
> >  }
> >
> > +/**
> > + * sd_uhs2_cmd_assemble() - build up UHS-II command packet which is embeded in
> > + *                          mmc_command structure
> > + * @cmd:       MMC command to executed
> > + * @uhs2_cmd:  UHS2 command corresponded to MMC command
> > + * @header:    Header field of UHS-II command cxpacket
> > + * @arg:       Argument field of UHS-II command packet
> > + * @payload:   Payload field of UHS-II command packet
> > + * @plen:      Payload length
> > + * @resp:      Response buffer is allocated by caller and it is used to keep
> > + *              the response of CM-TRAN command. For SD-TRAN command, uhs2_resp
> > + *              should be null and SD-TRAN command response should be stored in
> > + *              resp of mmc_command.
> > + * @resp_len:  Response buffer length
> > + *
> > + * Different from legacy SD command, there defined several types of packets
> > + * in UHS-II, which include CM-TRAN and SD-TRAN. These packets are then
> > + * transformed to differential signals and transmitted/received between
> > + * transceiver and receiver.
> > + *
> > + * The UHS-II packet structure(uhs2_cmd) are added in structure mmc_command
> > + * and be filled according to the inputed parameters provided by caller.
> > + *
> > + * For mmc requests, call this function before issuing command to SD card.
> > + * Host controller specific request function will send packet in uhs2_cmd
> > + * to UHS-II SD card.
> > + *
>
> I think we discussed the above functions description earlier. The
> above description is just way too overwhelming. What the function does
> is that fills out the uhs2_cmd data structure, that's it.
>
> As this is a static function, I wouldn't mind that you simply drop the
> entire function description above. Or try to make the description
> short and clear.

I will try to do that.

> > + */
> > +static void sd_uhs2_cmd_assemble(struct mmc_command *cmd,
> > +                             struct uhs2_command *uhs2_cmd,
> > +                             u16 header, u16 arg,
> > +                             u32 *payload, u8 plen, u8 *resp, u8 resp_len)
> > +{
> > +       uhs2_cmd->header = header;
> > +       uhs2_cmd->arg = arg;
> > +       uhs2_cmd->payload = payload;
> > +       uhs2_cmd->payload_len = plen * sizeof(u32);
> > +       uhs2_cmd->packet_len = uhs2_cmd->payload_len + 4;
> > +
> > +       cmd->uhs2_cmd = uhs2_cmd;
> > +       cmd->uhs2_resp = resp;
> > +       cmd->uhs2_resp_len = resp_len;
> > +}
> > +
> >  /*
> >   * Run the phy initialization sequence, which mainly relies on the UHS-II host
> >   * to check that we reach the expected electrical state, between the host and
> > @@ -52,16 +99,98 @@ static void sd_uhs2_power_off(struct mmc_host *host)
> >   */
> >  static int sd_uhs2_phy_init(struct mmc_host *host)
> >  {
> > -       return 0;
> > +       int err = 0;
> > +
> > +       /*
> > +        * Every host controller can assign its own function which is used
> > +        * to initialize PHY.
> > +        */
> > +       err = host->ops->uhs2_detect_init(host)
>
> It looks like you didn't declare this callback as part of the struct
> mmc_host_ops, so this does not even compile. Please fix that.
>
> I also suggest moving the above comment into the header file along
> with its declaration, as it's usually where we keep this information.
>
> Moreover, to make it clear what the callback is intended for, I
> suggest renaming it to "uhs2_phy_init".

There are 5 callback functions for UHS-II:
    int   uhs2_detect_init(struct mmc_host *host);
    int   uhs2_set_reg(struct mmc_host *host, enum uhs2_action act);
    void uhs2_disable_clk(struct mmc_host *host);
    void uhs2_enable_clk(struct mmc_host *host);
    void uhs2_post_attach_sd(struct mmc_host *host);
According to your suggestion, I plan to integrate them into a single function,
named "uhs2_do_action", since they all realize the specified function by
setting the controller.

> > +       if (err) {
> > +               pr_err("%s: fail to detect UHS2!\n", mmc_hostname(host));
>
> Maybe "failed to initial phy for UHS-II", is better?

Okay. The string will be modified in the next version.

> > +       }
> > +
> > +       return err;
> >  }
> >
> >  /*
> > - * Do the early initialization of the card, by sending the device init
> > -roadcast
> > + * Do the early initialization of the card, by sending the device init broadcast
>
> Looks like you are correcting a spelling mistake, which is good.
> However, please make this a part of the patch that introduced this,
> earlier in the series.

Do you mean to create a separate patch which only contains typo correction?
If yes, should I collect such changes in previously submitted files
and put them to
a separate patch file  in the next version, even though they are the
same between
previous and next version? Or just apply this rule to later versions?

> >  /*
> >   * Read the UHS-II configuration registers (CFG_REG) of the card, by sending it
> >   * commands and by parsing the responses. Store a copy of the relevant data in
> > - * card->uhs2_config.
> > + * host->uhs2_card_prop.
>
> This isn't correct. The code below is storing the configuration in
> card->uhs2_config, which is the correct thing to do.

Okay. I will rephrase the description in the next version.

> >
> > -/*
> > +/**
> >   * Based on the card's and host's UHS-II capabilities, let's update the
> >   * configuration of the card and the host. This may also include to move to a
> >   * greater speed range/mode. Depending on the updated configuration, we may
> > -eed
> > - * to do a soft reset of the card via sending it a GO_DORMANT_STATE command.
> > + * need to do a soft reset of the card via sending it a GO_DORMANT_STATE
> > + * command.
> >   *
> >   * In the final step, let's check if the card signals "config completion",
> > -hich
> > - * indicates that the card has moved from config state into active state.
> > + * which indicates that the card has moved from config state into active state.
>
> As I said earlier, please fix spelling mistakes as part of the
> patch(es) that introduced them.
>
> >   */
> >  static int sd_uhs2_config_write(struct mmc_host *host, struct mmc_card *card)
> >  {
> > +       struct mmc_command cmd = {0};
> > +       struct uhs2_command uhs2_cmd = {};
> > +       u16 header = 0, arg = 0;
> > +       u32 payload[2];
> > +       u8 nMinDataGap;
> > +       u8 plen;
> > +       u8 try;
> > +       int err;
> > +       u8 resp[5] = {0};
> > +       u8 resp_len = 5;
> > +
> > +       header = UHS2_NATIVE_PACKET |
> > +                UHS2_PACKET_TYPE_CCMD | card->uhs2_config.node_id;
> > +       arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> > +              UHS2_NATIVE_CMD_WRITE |
> > +              UHS2_NATIVE_CMD_PLEN_8B |
> > +              (UHS2_DEV_CONFIG_GEN_SET >> 8);
> > +
> > +       if (card->uhs2_config.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD &&
> > +           host->uhs2_caps.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD) {
> > +               /* Support HD */
> > +               host->flags |= MMC_UHS2_2L_HD;
> > +               nMinDataGap = 1;
> > +       } else {
> > +               /* Only support 2L-FD so far */
> > +               host->flags &= ~MMC_UHS2_2L_HD;
> > +               nMinDataGap = 3;
> > +       }
> > +
> > +       /*
> > +        * Most UHS-II cards only support FD and 2L-HD mode. Other lane numbers
> > +        * defined in UHS-II addendem Ver1.01 are optional.
> > +        */
> > +       host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> > +       card->uhs2_config.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
> > +
> > +       plen = 2;
> > +       payload[0] = card->uhs2_config.n_lanes_set <<
> > +                    UHS2_DEV_CONFIG_N_LANES_POS;
> > +       payload[1] = 0;
> > +       payload[0] = cpu_to_be32(payload[0]);
> > +       payload[1] = cpu_to_be32(payload[1]);
> > +
> > +       /*
> > +        * There is no payload because per spec, there should be
> > +        * no payload field for read CCMD.
> > +        * Plen is set in arg. Per spec, plen for read CCMD
> > +        * represents the len of read data which is assigned in payload
> > +        * of following RES (p136).
> > +        */
> > +       sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
> > +                         NULL, 0);
> > +
> > +       err = mmc_wait_for_cmd(host, &cmd, 0);
> > +       if (err) {
> > +               pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
> > +                      mmc_hostname(host), __func__, err);
> > +               return -EIO;
> > +       }
> > +
> > +       arg = ((UHS2_DEV_CONFIG_PHY_SET & 0xFF) << 8) |
> > +              UHS2_NATIVE_CMD_WRITE |
> > +              UHS2_NATIVE_CMD_PLEN_8B |
> > +              (UHS2_DEV_CONFIG_PHY_SET >> 8);
> > +
> > +       for (try = 0; try < 2; try++) {
>
> This loop looks a bit odd. Perhaps you can explain why we need this
> with a comment in the code?
>
> Optionally, we could potentially also try to move some part of it into
> a separate helper function and then just call that from here instead?
> In this way, we may be able to avoid the loop altogether and thus also
> the code should become more readable. What do you think?

Agree. I will try to do it in the next version.

> > +               if (!(resp[2] & 0x80))
> > +                       break;
> > +       }
> > +
> > +       /* Set host Config Setting registers */
> > +       if (!host->ops->uhs2_set_reg ||
>
> Again, I couldn't find this callback being declared, so I guess this
> doesn't compile. Please fix that.
>
> I agree that the callback should not be optional. However, I think
> this is far too late in the initialization process to check it. This
> can be checked already when adding the host in mmc_add_host(), in case
> the host supports UHS-II, for example.
>
> Moreover, I am questioning the name of the callback. It seems like we
> are going to use it for various UHS-II operations. The name
> "uhs2_set_reg" doesn't really explain this. Maybe "uhs2_do_action", or
> if you can come up with something even better, that would be great.

Agree. As mentioned above, I plan to use uhs2_do_action to  replace 5 UHS-II
callback functions. And I will check (host->ops->uhs2_do_action) at
the beginning
of the initialization process.

> > +           host->ops->uhs2_set_reg(host, SET_CONFIG)) {
> > +               pr_err("%s: %s: UHS2 SET_CONFIG fail!\n",
> > +                       mmc_hostname(host), __func__);
> > +               return -EIO;
> > +       }
> > +
> > +static int sd_uhs2_go_dormant(struct mmc_host *host, bool hibernate, u32 node_id)
> > +{
> > +
> > +       if (host->ops->uhs2_disable_clk)
>
> Again, another callback that lacks declaration.
>
> > +               host->ops->uhs2_disable_clk(host);
>
> In fact, rather than adding another callback, we could make use of the
> "->uhs2_set_reg" callback?
>
> Or, another option would be to use the ->uhs2_set_ios(). That would be
> similar to what we do for legacy SD cards with the ->set_ios()
> callback.
>
> For example, we can do like this:
> host->ios.power_mode = MMC_POWER_ON;
> host->ios.clock = 0;
> host->ops->uhs2_set_ios(host, &host->ios);
>
> What do you think? Maybe we need a separate host->ios_uhs2 for this too?

As I mentioned above, I intend to use integrated "uhs2_do_action()".
What do you think?

> > +
> > +static int sd_uhs2_change_speed(struct mmc_host *host, u32 node_id)
> > +{
> > +
> > +       /* restore sd clock */
> > +       mmc_delay(5);
> > +       if (host->ops->uhs2_enable_clk)
> > +               host->ops->uhs2_enable_clk(host);
>
> Ditto.
>
> > +
> > +       /*
> > +        * According to UHS-II Addendum Version 1.01, chapter 6.2.3, wait card
> > +        * switch to Active State
> > +        */
> > +       header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD |
> > +                host->card->uhs2_config.node_id;
>
> Didn't you pass node_id as an in-parameter? Why can't you use that?

Oops! I missed it accidentally in the previous version. I will update
it in the next version.

> > +       arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
> > +               UHS2_NATIVE_CMD_READ |
> > +               UHS2_NATIVE_CMD_PLEN_8B |
> > +               (UHS2_DEV_CONFIG_GEN_SET >> 8);
> >
> >
> > @@ -108,8 +724,70 @@ static int sd_uhs2_config_write(struct mmc_host *host, struct mmc_card *card)
> >   * be set through a legacy CMD6. Note that, the power limit that becomes set,
> >   * survives a soft reset through the GO_DORMANT_STATE command.
> >   */
> > -static int sd_uhs2_legacy_init(struct mmc_host *host, struct mmc_card *card)
> > +static int sd_uhs2_legacy_init(struct mmc_host *host)
>
> Please make this change from the patch that introduced this code.

Okay.

> >  {
> > +       int err;
> > +       u32 ocr, rocr;
> > +
> > +       WARN_ON(!host->claimed);
> > +
> > +       /* Send CMD0 to reset SD card */
> > +       mmc_go_idle(host);
> > +
> > +       /* Send CMD8 to communicate SD interface operation condition */
> > +       err = mmc_send_if_cond(host, host->ocr_avail);
> > +       if (err) {
> > +               pr_err("%s: %s: SEND_IF_COND fail!\n",
> > +                      mmc_hostname(host), __func__);
> > +               return err;
> > +       }
> > +
> > +       /*
> > +        * Send host capacity support information and activate card's
> > +        * initialization process.
> > +        */
> > +       err = mmc_send_app_op_cond(host, 0, &ocr);
> > +       if (err) {
> > +               pr_err("%s: %s: SD_SEND_OP_COND fail!\n",
> > +                      mmc_hostname(host), __func__);
> > +               return err;
> > +       }
> > +
> > +       if (host->ocr_avail_sd)
> > +               host->ocr_avail = host->ocr_avail_sd;
>
> Please drop this part. I don't want to encourage host's to use
> ocr_avail_sd (for reasons that we can discuss another time).

Okay.

> If we need something specific for UHS-II, then it's better to add that.
>
> > +
> > +       /*
> > +        * Some SD cards claims an out of spec VDD voltage range. Let's treat
> > +        * these bits as being in-valid and especially also bit7.
> > +        */
> > +       ocr &= ~0x7FFF;
> > +       rocr = mmc_select_voltage(host, ocr);
> > +
> > +       /*
> > +        * Some cards have zero value of rocr in UHS-II mode. Assign host's
> > +        * ocr value to rocr.
> > +        */
> > +       if (!rocr) {
> > +               if (host->ocr_avail) {
> > +                       rocr = host->ocr_avail;
> > +               } else {
> > +                       pr_err("%s: %s: there is no valid OCR.\n",
> > +                              mmc_hostname(host), __func__);
> > +                       return -EINVAL;
> > +               }
> > +       }
> > +
> > +       /*
> > +        * Get CID, send relative address, get CSD are the same as legacy
> > +        * sd, call mmc_sd_init_card() in sd.c directly
> > +        */
> > +       err = mmc_sd_init_card(host, rocr, NULL);
> > +       if (err) {
> > +               pr_err("%s: %s: mmc_sd_init_card() fail!\n",
> > +                      mmc_hostname(host), __func__);
> > +               return err;
> > +       }
>
> So this means we will start using the host callbacks for the legacy SD
> interface, like ->set_ios() for example.

I will remove this callback and reorganize codes in this portion.

> In other words, data in host->ios.* seems to be used, both for UHS-II
> and legacy SD. That can be messy for host drivers to manage, I think.
> Maybe we should add a separate host->ios_uhs2.*, that we use solely
> for UHS2 instead?

This topic can be discussed.
The ios structure can continue to be used after adding new definitions to
certain fields, for example, adding MMC_TIMING_UHS2 for ios.timing.

> There is also another problem here. mmc_sd_init_card() will allocate a
> new struct mmc_card and assign it to host->card, if it succeeds with
> initialization.
>
> By looking at the changes below, it looks like you will assign
> host->card, with the struct mmc_card that we have allocated for UHS-II
> in sd_uhs2_init_card(), prior to calling sd_uhs2_legacy_init(). Not
> only will this lead to a memory leak, but more importantly we will
> lose all the information that we have parsed/stored from the card for
> UHS-II, right?
>
> Don't we need to keep the UHS-II information of the card around? Or is
> it okay to throw it away after initialization?
>
> What am I missing?

You are right. I will reorganize this portion.

> > +
> >         return 0;
> >  }
> >
> > @@ -124,12 +802,16 @@ static int sd_uhs2_init_card(struct mmc_host *host)
> >         int err;
> >
> >         err = sd_uhs2_dev_init(host);
> > -       if (err)
> > +       if (err) {
> > +               pr_err("%s: UHS2 DEVICE_INIT fail!\n", mmc_hostname(host));
> >                 return err;
> > +       }
> >
> >         err = sd_uhs2_enum(host, &node_id);
> > -       if (err)
> > +       if (err) {
> > +               pr_err("%s: UHS2 ENUMERATE fail!\n", mmc_hostname(host));
> >                 return err;
> > +       }
> >
> >         card = mmc_alloc_card(host, &sd_type);
> >         if (IS_ERR(card))
> > @@ -142,15 +824,26 @@ static int sd_uhs2_init_card(struct mmc_host *host)
> >         if (err)
> >                 goto err;
> >
> > +       /* Change to Speed Range B if it is supported */
> > +       if (host->flags & MMC_UHS2_SPEED_B) {
>
> I noticed that you have added the "host->flags", to keep track of
> UHS-II states and some UHS-II capabilities of the host. I would rather
> see that UHS-II host capabilities should be part of the
> host->uhs2_caps.*.

Agree. I will move the "flags" field to struct sd_uhs2_caps{} in the
next version.

> When it comes to keeping track of UHS-II states, like when we want to
> move to a new speed mode for example, that may be better to keep as a
> part of a new host->ios_uhs2.*, as I kind of indicated above.

UHS-II speed mode is only set at initialization phase and it is not
changed before hardware reset.
Hence, I think it's not necessary to place sd_uhs2_change_speed() into
host->ios_uhs2.*.
Maybe we can discuss host->ios_uhs2.* after you check my next submission.

> > +               err = sd_uhs2_change_speed(host, node_id);
> > +               if (err) {
> > +                       pr_err("%s: %s: UHS2 sd_uhs2_change_speed() fail!\n",
> > +                               mmc_hostname(host), __func__);
> > +                       return err;
> > +               }
> > +       }
> > +
> >         err = sd_uhs2_config_write(host, card);
> >         if (err)
> >                 goto err;
> >
> > -       err = sd_uhs2_legacy_init(host, card);
> > +       host->card = card;
> > +
> > +       err = sd_uhs2_legacy_init(host);
> >         if (err)
> >                 goto err;
> >
> > -       host->card = card;
>
> This is the part that will lead to the memory leak of a struct mmc_card.

I will reorganize this portion to fix this memory leak.

> >         return 0;
> >
> >  err:
> > @@ -217,6 +910,78 @@ static int sd_uhs2_hw_reset(struct mmc_host *host)
> >         return 0;
> >  }
>
> [...]
>
> I have stopped the review at this point, let's see if we can conclude
> on the way forward around my comments on the parts above, to start
> with.
>
> Kind regards
> Uffe

I will start preparing for the next version submission after receiving
your response to my question.
Thank you for your patience.

kind regards
Jason Lai
Ulf Hansson Jan. 7, 2022, 5:08 p.m. UTC | #3
On Thu, 6 Jan 2022 at 11:31, Lai Jason <jasonlai.genesyslogic@gmail.com> wrote:
>
> On Wed, Dec 15, 2021 at 4:29 AM Ulf Hansson <ulf.hansson@linaro.org> wrote:
> >
> >> On Fri, 3 Dec 2021 at 11:51, Jason Lai <jasonlai.genesyslogic@gmail.com> wrote:
> > >
> > > From: Jason Lai <jason.lai@genesyslogic.com.tw>
> > >
> > > UHS-II card initialization flow is divided into 2 categories: PHY & Card.
> > > Part 1 - PHY Initialization:
> > >          Every host controller may need their own avtivation operation
> > >          to establish LINK between controller and card. So we add a new
> > >          member function(uhs2_detect_init) in struct mmc_host_ops for host
> > >          controller use.
> > > Part 2 - Card Initialization:
> > >          This part can be divided into 6 substeps.
> > >          1. Send UHS-II CCMD DEVICE_INIT to card.
> > >          2. Send UHS-II CCMD ENUMERATE to card.
> > >          3. Send UHS-II Native Read CCMD to obtain capabilities in CFG_REG
> > >             of card.
> > >          4. Host compares capabilities of host controller and  card,
> > >             then write the negotiated values to Setting field in CFG_REG
> > >             of card through UHS-II Native Write CCMD.
> > >          5. Switch host controller's clock to Range B if it is supported
> > >             by both host controller and card.
> > >          6. Execute legacy SD initialization flow.
> > > Part 3 - Provide a function to tranaform legacy SD command packet into
> > >          UHS-II SD-TRAN DCMD packet.
> > >
> > > Most of the code added above came from Intel's original patch[1].
> > >
> > > [1]
> > > https://patchwork.kernel.org/project/linux-mmc/patch/1419672479-30852-2-
> > > git-send-email-yi.y.sun@intel.com/
> > >
> > > Signed-off-by: Jason Lai <jason.lai@genesyslogic.com.tw>
> > > ---
> > >  drivers/mmc/core/sd_uhs2.c | 831 ++++++++++++++++++++++++++++++++++++-
> > >  1 file changed, 810 insertions(+), 21 deletions(-)
> > >
> > > diff --git a/drivers/mmc/core/sd_uhs2.c b/drivers/mmc/core/sd_uhs2.c
> > > index 24aa51a6d..d13283d54 100644
> > > --- a/drivers/mmc/core/sd_uhs2.c
> > > +++ b/drivers/mmc/core/sd_uhs2.c
> > > @@ -3,6 +3,7 @@
> > >
> > >  static const unsigned int sd_uhs2_freqs[] = { 52000000, 26000000 };
> > >
> > > -static int sd_uhs2_set_ios(struct mmc_host *host)
> > > +static void sd_uhs2_set_ios(struct mmc_host *host)
> >
> > Please don't change the function to return void. It's better to allow
> > the callback to return an error code, even if that might not be of
> > benefit for your particular host variant.
>
> I have a question about the return type of this function. In
> sd_uhs2_set_ios(), we only called
> host->ops->set_ios() and the return type of that function was VOID. So
> is there a reason
> that this function must has a non-void return type?

I think the original ->set_ios() callback should have been "int"
rather than void. It's clear that those callbacks can actually fail,
but today there is no way for them to report an error.

Therefore, please use 'int'.

[...]

> > >  static int sd_uhs2_phy_init(struct mmc_host *host)
> > >  {
> > > -       return 0;
> > > +       int err = 0;
> > > +
> > > +       /*
> > > +        * Every host controller can assign its own function which is used
> > > +        * to initialize PHY.
> > > +        */
> > > +       err = host->ops->uhs2_detect_init(host)
> >
> > It looks like you didn't declare this callback as part of the struct
> > mmc_host_ops, so this does not even compile. Please fix that.
> >
> > I also suggest moving the above comment into the header file along
> > with its declaration, as it's usually where we keep this information.
> >
> > Moreover, to make it clear what the callback is intended for, I
> > suggest renaming it to "uhs2_phy_init".
>
> There are 5 callback functions for UHS-II:
>     int   uhs2_detect_init(struct mmc_host *host);
>     int   uhs2_set_reg(struct mmc_host *host, enum uhs2_action act);
>     void uhs2_disable_clk(struct mmc_host *host);
>     void uhs2_enable_clk(struct mmc_host *host);
>     void uhs2_post_attach_sd(struct mmc_host *host);
> According to your suggestion, I plan to integrate them into a single function,
> named "uhs2_do_action", since they all realize the specified function by
> setting the controller.

I don't mind that we add a few callbacks to support UHS-II, but at the
same time it gets silly to have one for each and every operation.

That said, I think the above approach that you suggest is worth a try.
Let's see what this can bring us to.

>
> > > +       if (err) {
> > > +               pr_err("%s: fail to detect UHS2!\n", mmc_hostname(host));
> >
> > Maybe "failed to initial phy for UHS-II", is better?
>
> Okay. The string will be modified in the next version.
>
> > > +       }
> > > +
> > > +       return err;
> > >  }
> > >
> > >  /*
> > > - * Do the early initialization of the card, by sending the device init
> > > -roadcast
> > > + * Do the early initialization of the card, by sending the device init broadcast
> >
> > Looks like you are correcting a spelling mistake, which is good.
> > However, please make this a part of the patch that introduced this,
> > earlier in the series.
>
> Do you mean to create a separate patch which only contains typo correction?

I would appreciate it, if you can amend my original patch to fix my mistakes.

[...]

> > > +
> > > +static int sd_uhs2_go_dormant(struct mmc_host *host, bool hibernate, u32 node_id)
> > > +{
> > > +
> > > +       if (host->ops->uhs2_disable_clk)
> >
> > Again, another callback that lacks declaration.
> >
> > > +               host->ops->uhs2_disable_clk(host);
> >
> > In fact, rather than adding another callback, we could make use of the
> > "->uhs2_set_reg" callback?
> >
> > Or, another option would be to use the ->uhs2_set_ios(). That would be
> > similar to what we do for legacy SD cards with the ->set_ios()
> > callback.
> >
> > For example, we can do like this:
> > host->ios.power_mode = MMC_POWER_ON;
> > host->ios.clock = 0;
> > host->ops->uhs2_set_ios(host, &host->ios);
> >
> > What do you think? Maybe we need a separate host->ios_uhs2 for this too?
>
> As I mentioned above, I intend to use integrated "uhs2_do_action()".
> What do you think?

As stated, seems reasonable, let's give it a try!

[...]

> > > +        * Get CID, send relative address, get CSD are the same as legacy
> > > +        * sd, call mmc_sd_init_card() in sd.c directly
> > > +        */
> > > +       err = mmc_sd_init_card(host, rocr, NULL);
> > > +       if (err) {
> > > +               pr_err("%s: %s: mmc_sd_init_card() fail!\n",
> > > +                      mmc_hostname(host), __func__);
> > > +               return err;
> > > +       }
> >
> > So this means we will start using the host callbacks for the legacy SD
> > interface, like ->set_ios() for example.
>
> I will remove this callback and reorganize codes in this portion.
>
> > In other words, data in host->ios.* seems to be used, both for UHS-II
> > and legacy SD. That can be messy for host drivers to manage, I think.
> > Maybe we should add a separate host->ios_uhs2.*, that we use solely
> > for UHS2 instead?
>
> This topic can be discussed.
> The ios structure can continue to be used after adding new definitions to
> certain fields, for example, adding MMC_TIMING_UHS2 for ios.timing.

I don't think it's going to play well for existing mmc host drivers to
use the current host->ios.*.

Let's try to add a new host->ios_uhs2.* and add the data we need for
UHS-II in there.

[...]

> I will start preparing for the next version submission after receiving
> your response to my question.
> Thank you for your patience.

Great!

If you need some additional guidance at this point, just ask.
Otherwise I will defer to review your next version of the series.

Kind regards
Uffe
Lai Jason Jan. 14, 2022, 3:18 a.m. UTC | #4
On Wed, Dec 15, 2021 at 4:29 AM Ulf Hansson <ulf.hansson@linaro.org> wrote:
>
> On Fri, 3 Dec 2021 at 11:51, Jason Lai <jasonlai.genesyslogic@gmail.com> wrote:
> >
> > From: Jason Lai <jason.lai@genesyslogic.com.tw>
> >
> > UHS-II card initialization flow is divided into 2 categories: PHY & Card.
> > Part 1 - PHY Initialization:
> >          Every host controller may need their own avtivation operation
> >          to establish LINK between controller and card. So we add a new
> >          member function(uhs2_detect_init) in struct mmc_host_ops for host
> >          controller use.
> > Part 2 - Card Initialization:
> >          This part can be divided into 6 substeps.
> >          1. Send UHS-II CCMD DEVICE_INIT to card.
> >          2. Send UHS-II CCMD ENUMERATE to card.
> >          3. Send UHS-II Native Read CCMD to obtain capabilities in CFG_REG
> >             of card.
> >          4. Host compares capabilities of host controller and  card,
> >             then write the negotiated values to Setting field in CFG_REG
> >             of card through UHS-II Native Write CCMD.
> >          5. Switch host controller's clock to Range B if it is supported
> >             by both host controller and card.
> >          6. Execute legacy SD initialization flow.
> > Part 3 - Provide a function to tranaform legacy SD command packet into
> >          UHS-II SD-TRAN DCMD packet.
> >
> > Most of the code added above came from Intel's original patch[1].
> >
> > [1]
> > https://patchwork.kernel.org/project/linux-mmc/patch/1419672479-30852-2-
> > git-send-email-yi.y.sun@intel.com/
> >
> > Signed-off-by: Jason Lai <jason.lai@genesyslogic.com.tw>
> > ---
> >  drivers/mmc/core/sd_uhs2.c | 831 ++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 810 insertions(+), 21 deletions(-)
> >
> > diff --git a/drivers/mmc/core/sd_uhs2.c b/drivers/mmc/core/sd_uhs2.c
> > index 24aa51a6d..d13283d54 100644
> > --- a/drivers/mmc/core/sd_uhs2.c
> > +++ b/drivers/mmc/core/sd_uhs2.c
> > @@ -3,6 +3,7 @@

[...]

> > +/**
> > + * sd_uhs2_cmd_assemble() - build up UHS-II command packet which is embeded in
> > + *                          mmc_command structure
> > + * @cmd:       MMC command to executed
> > + * @uhs2_cmd:  UHS2 command corresponded to MMC command
> > + * @header:    Header field of UHS-II command cxpacket
> > + * @arg:       Argument field of UHS-II command packet
> > + * @payload:   Payload field of UHS-II command packet
> > + * @plen:      Payload length
> > + * @resp:      Response buffer is allocated by caller and it is used to keep
> > + *              the response of CM-TRAN command. For SD-TRAN command, uhs2_resp
> > + *              should be null and SD-TRAN command response should be stored in
> > + *              resp of mmc_command.
> > + * @resp_len:  Response buffer length
> > + *
> > + * Different from legacy SD command, there defined several types of packets
> > + * in UHS-II, which include CM-TRAN and SD-TRAN. These packets are then
> > + * transformed to differential signals and transmitted/received between
> > + * transceiver and receiver.
> > + *
> > + * The UHS-II packet structure(uhs2_cmd) are added in structure mmc_command
> > + * and be filled according to the inputed parameters provided by caller.
> > + *
> > + * For mmc requests, call this function before issuing command to SD card.
> > + * Host controller specific request function will send packet in uhs2_cmd
> > + * to UHS-II SD card.
> > + *
>
> I think we discussed the above functions description earlier. The
> above description is just way too overwhelming. What the function does
> is that fills out the uhs2_cmd data structure, that's it.
>
> As this is a static function, I wouldn't mind that you simply drop the
> entire function description above. Or try to make the description
> short and clear.

I try to make the function description more briefly:
/**
 * sd_uhs2_cmd_assemble() - build up UHS-II command packet which is embeded in
 *                          mmc_command structure
 * @cmd: MMC command to executed
 * @uhs2_cmd: UHS2 command corresponded to MMC command
 * @header: Header field of UHS-II command cxpacket
 * @arg: Argument field of UHS-II command packet
 * @payload: Payload field of UHS-II command packet
 * @plen: Payload length
 * @resp: Response buffer is allocated by caller and it is used to keep
 *              the response of CM-TRAN command. For SD-TRAN command, uhs2_resp
 *              should be null and SD-TRAN command response should be stored in
 *              resp of mmc_command.
 * @resp_len: Response buffer length
 *
 * The uhs2_command structure contains message packets which are transmited/
 * received on UHS-II bus. This function fills in the contents of uhs2_command
 * structure and embededs UHS2 command into mmc_command structure, which is used
 * in legacy SD operation functions.
 *
 */
What do you think?

kind regards,
Jason Lai

> [...]
>
> I have stopped the review at this point, let's see if we can conclude
> on the way forward around my comments on the parts above, to start
> with.
>
> Kind regards
> Uffe
diff mbox series

Patch

diff --git a/drivers/mmc/core/sd_uhs2.c b/drivers/mmc/core/sd_uhs2.c
index 24aa51a6d..d13283d54 100644
--- a/drivers/mmc/core/sd_uhs2.c
+++ b/drivers/mmc/core/sd_uhs2.c
@@ -3,6 +3,7 @@ 
  * Copyright (C) 2021 Linaro Ltd
  *
  * Author: Ulf Hansson <ulf.hansson@linaro.org>
+ * Author: Jason Lai <jason.lai@genesyslogic.com.tw>
  *
  * Support for SD UHS-II cards
  */
@@ -10,29 +11,31 @@ 
 
 #include <linux/mmc/host.h>
 #include <linux/mmc/card.h>
+#include <linux/mmc/sd_uhs2.h>
 
 #include "core.h"
 #include "bus.h"
 #include "sd.h"
 #include "mmc_ops.h"
+#include "sd_uhs2.h"
 
 static const unsigned int sd_uhs2_freqs[] = { 52000000, 26000000 };
 
-static int sd_uhs2_set_ios(struct mmc_host *host)
+static void sd_uhs2_set_ios(struct mmc_host *host)
 {
 	struct mmc_ios *ios = &host->ios;
 
-	return host->ops->uhs2_set_ios(host, ios);
+	host->ops->set_ios(host, ios);
 }
 
-static int sd_uhs2_power_up(struct mmc_host *host)
+static void sd_uhs2_power_up(struct mmc_host *host)
 {
 	host->ios.vdd = fls(host->ocr_avail) - 1;
 	host->ios.clock = host->f_init;
 	host->ios.timing = MMC_TIMING_SD_UHS2;
 	host->ios.power_mode = MMC_POWER_UP;
 
-	return sd_uhs2_set_ios(host);
+	sd_uhs2_set_ios(host);
 }
 
 static void sd_uhs2_power_off(struct mmc_host *host)
@@ -45,6 +48,50 @@  static void sd_uhs2_power_off(struct mmc_host *host)
 	sd_uhs2_set_ios(host);
 }
 
+/**
+ * sd_uhs2_cmd_assemble() - build up UHS-II command packet which is embeded in
+ *                          mmc_command structure
+ * @cmd:	MMC command to executed
+ * @uhs2_cmd:	UHS2 command corresponded to MMC command
+ * @header:	Header field of UHS-II command cxpacket
+ * @arg:	Argument field of UHS-II command packet
+ * @payload:	Payload field of UHS-II command packet
+ * @plen:	Payload length
+ * @resp:	Response buffer is allocated by caller and it is used to keep
+ *              the response of CM-TRAN command. For SD-TRAN command, uhs2_resp
+ *              should be null and SD-TRAN command response should be stored in
+ *              resp of mmc_command.
+ * @resp_len:	Response buffer length
+ *
+ * Different from legacy SD command, there defined several types of packets
+ * in UHS-II, which include CM-TRAN and SD-TRAN. These packets are then
+ * transformed to differential signals and transmitted/received between
+ * transceiver and receiver.
+ *
+ * The UHS-II packet structure(uhs2_cmd) are added in structure mmc_command
+ * and be filled according to the inputed parameters provided by caller.
+ *
+ * For mmc requests, call this function before issuing command to SD card.
+ * Host controller specific request function will send packet in uhs2_cmd
+ * to UHS-II SD card.
+ *
+ */
+static void sd_uhs2_cmd_assemble(struct mmc_command *cmd,
+			      struct uhs2_command *uhs2_cmd,
+			      u16 header, u16 arg,
+			      u32 *payload, u8 plen, u8 *resp, u8 resp_len)
+{
+	uhs2_cmd->header = header;
+	uhs2_cmd->arg = arg;
+	uhs2_cmd->payload = payload;
+	uhs2_cmd->payload_len = plen * sizeof(u32);
+	uhs2_cmd->packet_len = uhs2_cmd->payload_len + 4;
+
+	cmd->uhs2_cmd = uhs2_cmd;
+	cmd->uhs2_resp = resp;
+	cmd->uhs2_resp_len = resp_len;
+}
+
 /*
  * Run the phy initialization sequence, which mainly relies on the UHS-II host
  * to check that we reach the expected electrical state, between the host and
@@ -52,16 +99,98 @@  static void sd_uhs2_power_off(struct mmc_host *host)
  */
 static int sd_uhs2_phy_init(struct mmc_host *host)
 {
-	return 0;
+	int err = 0;
+
+	/*
+	 * Every host controller can assign its own function which is used
+	 * to initialize PHY.
+	 */
+	err = host->ops->uhs2_detect_init(host)
+	if (err) {
+		pr_err("%s: fail to detect UHS2!\n", mmc_hostname(host));
+	}
+
+	return err;
 }
 
 /*
- * Do the early initialization of the card, by sending the device init
-roadcast
+ * Do the early initialization of the card, by sending the device init broadcast
  * command and wait for the process to be completed.
  */
 static int sd_uhs2_dev_init(struct mmc_host *host)
 {
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u32 cnt;
+	u32 dap, gap, resp_gap;
+	u16 header = 0, arg = 0;
+	u32 payload[1];
+	u8 plen = 1;
+	u8 gd = 0, cf = 1;
+	u8 resp[6] = {0};
+	u8 resp_len = 6;
+	int err;
+
+	dap = host->uhs2_caps.dap;
+	gap = host->uhs2_caps.gap;
+
+	header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
+	arg = ((UHS2_DEV_CMD_DEVICE_INIT & 0xFF) << 8) |
+	       UHS2_NATIVE_CMD_WRITE |
+	       UHS2_NATIVE_CMD_PLEN_4B |
+	       (UHS2_DEV_CMD_DEVICE_INIT >> 8);
+
+	/*
+	 * Refer to UHS-II Addendum Version 1.02 section 6.3.1.
+	 * Max. time from DEVICE_INIT CCMD EOP reception on Device
+	 * Rx to its SOP transmission on Device Tx(Tfwd_init_cmd) is
+	 * 1 second.
+	 */
+	cmd.busy_timeout = 1000;
+
+	/*
+	 * Refer to UHS-II Addendum Version 1.02 section 6.2.6.3.
+	 * When the number of the DEVICE_INIT commands is reach to
+	 * 30 tiems, Host shall stop issuing DEVICE_INIT command
+	 * and regard it as an error.
+	 */
+	for (cnt = 0; cnt < 30; cnt++) {
+		payload[0] = ((dap & 0xF) << 12) |
+			     (cf << 11)         |
+			     ((gd & 0xF) << 4)  |
+			     (gap & 0xF);
+
+		sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
+				  payload, plen, resp, resp_len);
+
+		err = mmc_wait_for_cmd(host, &cmd, 0);
+
+		if (err) {
+			pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+			       mmc_hostname(host), __func__, err);
+			return -EIO;
+		}
+
+		if (resp[3] != (UHS2_DEV_CMD_DEVICE_INIT & 0xFF)) {
+			pr_err("%s: DEVICE_INIT response is wrong!\n",
+			       mmc_hostname(host));
+			return -EIO;
+		}
+
+		if (resp[5] & 0x8) {
+			host->group_desc = gd;
+			break;
+		}
+		resp_gap = resp[4] & 0x0F;
+		if (gap == resp_gap)
+			gd++;
+	}
+	if (cnt == 30) {
+		pr_err("%s: DEVICE_INIT fail, already 30 times!\n",
+		       mmc_hostname(host));
+		return -EIO;
+	}
+
 	return 0;
 }
 
@@ -72,32 +201,519 @@  static int sd_uhs2_dev_init(struct mmc_host *host)
  */
 static int sd_uhs2_enum(struct mmc_host *host, u32 *node_id)
 {
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u16 header = 0, arg = 0;
+	u32 payload[1];
+	u8 plen = 1;
+	u8 id_f = 0xF, id_l = 0x0;
+	u8 resp[8] = {0};
+	u8 resp_len = 8;
+	int err;
+
+	header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD;
+	arg = ((UHS2_DEV_CMD_ENUMERATE & 0xFF) << 8) |
+	       UHS2_NATIVE_CMD_WRITE |
+	       UHS2_NATIVE_CMD_PLEN_4B |
+	       (UHS2_DEV_CMD_ENUMERATE >> 8);
+
+	payload[0] = (id_f << 4) | id_l;
+
+	sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
+			  resp, resp_len);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	if (resp[3] != (UHS2_DEV_CMD_ENUMERATE & 0xFF)) {
+		pr_err("%s: ENUMERATE response is wrong!\n",
+		       mmc_hostname(host));
+		return -EIO;
+	}
+
+	id_f = (resp[4] >> 4) & 0xF;
+	id_l = resp[4] & 0xF;
+	*node_id = id_f;
+
 	return 0;
 }
 
 /*
  * Read the UHS-II configuration registers (CFG_REG) of the card, by sending it
  * commands and by parsing the responses. Store a copy of the relevant data in
- * card->uhs2_config.
+ * host->uhs2_card_prop.
  */
 static int sd_uhs2_config_read(struct mmc_host *host, struct mmc_card *card)
 {
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u16 header = 0, arg = 0;
+	u32 cap;
+	int err;
+
+	header = UHS2_NATIVE_PACKET |
+		 UHS2_PACKET_TYPE_CCMD |
+		 card->uhs2_config.node_id;
+	arg = ((UHS2_DEV_CONFIG_GEN_CAPS & 0xFF) << 8) |
+	       UHS2_NATIVE_CMD_READ |
+	       UHS2_NATIVE_CMD_PLEN_4B |
+	       (UHS2_DEV_CONFIG_GEN_CAPS >> 8);
+
+	/* There is no payload because per spec, there should be
+	 * no payload field for read CCMD.
+	 * Plen is set in arg. Per spec, plen for read CCMD
+	 * represents the len of read data which is assigned in payload
+	 * of following RES (p136).
+	 */
+	sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return err;
+	}
+
+	cap = cmd.resp[0];
+	card->uhs2_config.n_lanes =
+				(cap >> UHS2_DEV_CONFIG_N_LANES_POS) &
+				UHS2_DEV_CONFIG_N_LANES_MASK;
+	card->uhs2_config.dadr_len =
+				(cap >> UHS2_DEV_CONFIG_DADR_POS) &
+				UHS2_DEV_CONFIG_DADR_MASK;
+	card->uhs2_config.app_type =
+				(cap >> UHS2_DEV_CONFIG_APP_POS) &
+				UHS2_DEV_CONFIG_APP_MASK;
+
+	arg = ((UHS2_DEV_CONFIG_PHY_CAPS & 0xFF) << 8) |
+	       UHS2_NATIVE_CMD_READ |
+	       UHS2_NATIVE_CMD_PLEN_8B |
+	      (UHS2_DEV_CONFIG_PHY_CAPS >> 8);
+
+	sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	cap = cmd.resp[0];
+	card->uhs2_config.phy_minor_rev =
+				cap & UHS2_DEV_CONFIG_PHY_MINOR_MASK;
+	card->uhs2_config.phy_major_rev =
+				(cap >> UHS2_DEV_CONFIG_PHY_MAJOR_POS) &
+				 UHS2_DEV_CONFIG_PHY_MAJOR_MASK;
+	card->uhs2_config.can_hibernate =
+				(cap >> UHS2_DEV_CONFIG_CAN_HIBER_POS) &
+				 UHS2_DEV_CONFIG_CAN_HIBER_MASK;
+
+	cap = cmd.resp[1];
+	card->uhs2_config.n_lss_sync =
+				cap & UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
+	card->uhs2_config.n_lss_dir =
+				(cap >> UHS2_DEV_CONFIG_N_LSS_DIR_POS) &
+				UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
+	if (card->uhs2_config.n_lss_sync == 0)
+		card->uhs2_config.n_lss_sync = 16 << 2;
+	else
+		card->uhs2_config.n_lss_sync <<= 2;
+
+	if (card->uhs2_config.n_lss_dir == 0)
+		card->uhs2_config.n_lss_dir = 16 << 3;
+	else
+		card->uhs2_config.n_lss_dir <<= 3;
+
+	arg = ((UHS2_DEV_CONFIG_LINK_TRAN_CAPS & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_READ |
+		UHS2_NATIVE_CMD_PLEN_8B |
+		(UHS2_DEV_CONFIG_LINK_TRAN_CAPS >> 8);
+
+	sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, NULL, 0, NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	cap = cmd.resp[0];
+	card->uhs2_config.link_minor_rev =
+				cap & UHS2_DEV_CONFIG_LT_MINOR_MASK;
+	card->uhs2_config.link_major_rev =
+				(cap >> UHS2_DEV_CONFIG_LT_MAJOR_POS) &
+				UHS2_DEV_CONFIG_LT_MAJOR_MASK;
+	card->uhs2_config.n_fcu =
+				(cap >> UHS2_DEV_CONFIG_N_FCU_POS) &
+				UHS2_DEV_CONFIG_N_FCU_MASK;
+	card->uhs2_config.dev_type =
+				(cap >>UHS2_DEV_CONFIG_DEV_TYPE_POS) &
+				UHS2_DEV_CONFIG_DEV_TYPE_MASK;
+	card->uhs2_config.maxblk_len =
+				(cap >>UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) &
+				UHS2_DEV_CONFIG_MAX_BLK_LEN_MASK;
+
+	cap = cmd.resp[1];
+	card->uhs2_config.n_data_gap =
+				cap & UHS2_DEV_CONFIG_N_DATA_GAP_MASK;
+	if (card->uhs2_config.n_fcu == 0)
+		card->uhs2_config.n_fcu = 256;
+
 	return 0;
 }
 
-/*
+/**
  * Based on the card's and host's UHS-II capabilities, let's update the
  * configuration of the card and the host. This may also include to move to a
  * greater speed range/mode. Depending on the updated configuration, we may
-eed
- * to do a soft reset of the card via sending it a GO_DORMANT_STATE command.
+ * need to do a soft reset of the card via sending it a GO_DORMANT_STATE
+ * command.
  *
  * In the final step, let's check if the card signals "config completion",
-hich
- * indicates that the card has moved from config state into active state.
+ * which indicates that the card has moved from config state into active state.
  */
 static int sd_uhs2_config_write(struct mmc_host *host, struct mmc_card *card)
 {
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u16 header = 0, arg = 0;
+	u32 payload[2];
+	u8 nMinDataGap;
+	u8 plen;
+	u8 try;
+	int err;
+	u8 resp[5] = {0};
+	u8 resp_len = 5;
+
+	header = UHS2_NATIVE_PACKET |
+		 UHS2_PACKET_TYPE_CCMD | card->uhs2_config.node_id;
+	arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
+	       UHS2_NATIVE_CMD_WRITE |
+	       UHS2_NATIVE_CMD_PLEN_8B |
+	       (UHS2_DEV_CONFIG_GEN_SET >> 8);
+
+	if (card->uhs2_config.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD &&
+	    host->uhs2_caps.n_lanes == UHS2_DEV_CONFIG_2L_HD_FD) {
+		/* Support HD */
+		host->flags |= MMC_UHS2_2L_HD;
+		nMinDataGap = 1;
+	} else {
+		/* Only support 2L-FD so far */
+		host->flags &= ~MMC_UHS2_2L_HD;
+		nMinDataGap = 3;
+	}
+
+	/*
+	 * Most UHS-II cards only support FD and 2L-HD mode. Other lane numbers
+	 * defined in UHS-II addendem Ver1.01 are optional.
+	 */
+	host->uhs2_caps.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
+	card->uhs2_config.n_lanes_set = UHS2_DEV_CONFIG_GEN_SET_2L_FD_HD;
+
+	plen = 2;
+	payload[0] = card->uhs2_config.n_lanes_set <<
+		     UHS2_DEV_CONFIG_N_LANES_POS;
+	payload[1] = 0;
+	payload[0] = cpu_to_be32(payload[0]);
+	payload[1] = cpu_to_be32(payload[1]);
+
+	/*
+	 * There is no payload because per spec, there should be
+	 * no payload field for read CCMD.
+	 * Plen is set in arg. Per spec, plen for read CCMD
+	 * represents the len of read data which is assigned in payload
+	 * of following RES (p136).
+	 */
+	sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
+			  NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	arg = ((UHS2_DEV_CONFIG_PHY_SET & 0xFF) << 8) |
+	       UHS2_NATIVE_CMD_WRITE |
+	       UHS2_NATIVE_CMD_PLEN_8B |
+	       (UHS2_DEV_CONFIG_PHY_SET >> 8);
+
+	for (try = 0; try < 2; try++) {
+		plen = 2;
+
+		if (host->uhs2_caps.speed_range ==
+			UHS2_DEV_CONFIG_PHY_SET_SPEED_B) {
+			host->flags |= MMC_UHS2_SPEED_B;
+			card->uhs2_config.speed_range_set =
+					UHS2_DEV_CONFIG_PHY_SET_SPEED_B;
+		} else {
+			card->uhs2_config.speed_range_set =
+					UHS2_DEV_CONFIG_PHY_SET_SPEED_A;
+			host->flags &= ~MMC_UHS2_SPEED_B;
+		}
+
+		payload[0] = card->uhs2_config.speed_range_set <<
+					UHS2_DEV_CONFIG_PHY_SET_SPEED_POS;
+
+		card->uhs2_config.n_lss_sync_set =
+			(min(card->uhs2_config.n_lss_sync,
+			     host->uhs2_caps.n_lss_sync) >> 2) &
+			UHS2_DEV_CONFIG_N_LSS_SYN_MASK;
+		host->uhs2_caps.n_lss_sync_set =
+			card->uhs2_config.n_lss_sync_set;
+
+		if (try == 0) {
+			host->uhs2_caps.n_lss_dir_set =
+				(card->uhs2_config.n_lss_dir >> 3) &
+				UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
+			card->uhs2_config.n_lss_dir_set =
+				((host->uhs2_caps.n_lss_dir >> 3) + 1) &
+				UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
+		} else {
+			card->uhs2_config.n_lss_dir_set =
+				(max(card->uhs2_config.n_lss_dir,
+				     host->uhs2_caps.n_lss_dir) >> 3) &
+				UHS2_DEV_CONFIG_N_LSS_DIR_MASK;
+			host->uhs2_caps.n_lss_dir_set =
+				card->uhs2_config.n_lss_dir_set;
+		}
+
+		payload[1] = (card->uhs2_config.n_lss_dir_set <<
+					UHS2_DEV_CONFIG_N_LSS_DIR_POS) |
+			     card->uhs2_config.n_lss_sync_set;
+		payload[0] = cpu_to_be32(payload[0]);
+		payload[1] = cpu_to_be32(payload[1]);
+
+		resp_len = 4;
+		memset(resp, 0, sizeof(resp));
+
+		sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg,
+				  payload, plen, resp, resp_len);
+
+		err = mmc_wait_for_cmd(host, &cmd, 0);
+		if (err) {
+			pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+			       mmc_hostname(host), __func__, err);
+			return -EIO;
+		}
+
+		if (!(resp[2] & 0x80))
+			break;
+	}
+
+	arg = ((UHS2_DEV_CONFIG_LINK_TRAN_SET & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_WRITE |
+		UHS2_NATIVE_CMD_PLEN_8B |
+		(UHS2_DEV_CONFIG_LINK_TRAN_SET >> 8);
+
+	plen = 2;
+
+	if (card->uhs2_config.app_type == UHS2_DEV_CONFIG_APP_SD_MEM)
+		card->uhs2_config.maxblk_len_set =
+			UHS2_DEV_CONFIG_LT_SET_MAX_BLK_LEN;
+	else
+		card->uhs2_config.maxblk_len_set =
+			min(card->uhs2_config.maxblk_len,
+			    host->uhs2_caps.maxblk_len);
+	host->uhs2_caps.maxblk_len_set =
+			card->uhs2_config.maxblk_len_set;
+
+	card->uhs2_config.n_fcu_set =
+			min(card->uhs2_config.n_fcu,
+			    host->uhs2_caps.n_fcu);
+	host->uhs2_caps.n_fcu_set = card->uhs2_config.n_fcu_set;
+
+	card->uhs2_config.n_data_gap_set =
+			max(nMinDataGap, card->uhs2_config.n_data_gap);
+	host->uhs2_caps.n_data_gap_set =
+			card->uhs2_config.n_data_gap_set;
+
+	host->uhs2_caps.max_retry_set = 3;
+	card->uhs2_config.max_retry_set = host->uhs2_caps.max_retry_set;
+
+	payload[0] = (card->uhs2_config.maxblk_len_set <<
+					UHS2_DEV_CONFIG_MAX_BLK_LEN_POS) |
+		     (card->uhs2_config.max_retry_set <<
+					UHS2_DEV_CONFIG_LT_SET_MAX_RETRY_POS) |
+		     (card->uhs2_config.n_fcu_set <<
+					UHS2_DEV_CONFIG_N_FCU_POS);
+	payload[1] = card->uhs2_config.n_data_gap_set;
+	payload[0] = cpu_to_be32(payload[0]);
+	payload[1] = cpu_to_be32(payload[1]);
+
+	sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
+			  NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+			mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
+	       UHS2_NATIVE_CMD_WRITE |
+	       UHS2_NATIVE_CMD_PLEN_8B |
+	       (UHS2_DEV_CONFIG_GEN_SET >> 8);
+
+	plen = 2;
+	payload[0] = 0;
+	payload[1] = UHS2_DEV_CONFIG_GEN_SET_CFG_COMPLETE;
+	payload[0] = cpu_to_be32(payload[0]);
+	payload[1] = cpu_to_be32(payload[1]);
+
+	resp_len = 5;
+	memset(resp, 0, sizeof(resp));
+	sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
+			  resp, resp_len);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	/* Set host Config Setting registers */
+	if (!host->ops->uhs2_set_reg ||
+	    host->ops->uhs2_set_reg(host, SET_CONFIG)) {
+		pr_err("%s: %s: UHS2 SET_CONFIG fail!\n",
+			mmc_hostname(host), __func__);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int sd_uhs2_go_dormant(struct mmc_host *host, bool hibernate, u32 node_id)
+{
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u16 header = 0, arg = 0;
+	u32 payload[1];
+	u8 plen = 1;
+	int err;
+
+	/* Disable Normal INT */
+	if (!host->ops->uhs2_set_reg ||
+	    host->ops->uhs2_set_reg(host, DISABLE_INT)) {
+		pr_err("%s: %s: UHS2 DISABLE_INT fail!\n",
+		       mmc_hostname(host), __func__);
+		return -EIO;
+	}
+
+	header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD | node_id;
+
+	arg = ((UHS2_DEV_CMD_GO_DORMANT_STATE & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_WRITE |
+		UHS2_NATIVE_CMD_PLEN_4B |
+		(UHS2_DEV_CMD_GO_DORMANT_STATE >> 8);
+
+	if (hibernate)
+		payload[0] = UHS2_DEV_CMD_DORMANT_HIBER;
+
+	sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd, header, arg, payload, plen,
+			  NULL, 0);
+
+	err = mmc_wait_for_cmd(host, &cmd, 0);
+	if (err) {
+		pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	/* Check Dormant State in Present */
+	if (!host->ops->uhs2_set_reg ||
+	    host->ops->uhs2_set_reg(host, CHECK_DORMANT)) {
+		pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail!\n",
+		       mmc_hostname(host), __func__);
+		return -EIO;
+	}
+
+	if (host->ops->uhs2_disable_clk)
+		host->ops->uhs2_disable_clk(host);
+
+	return 0;
+}
+
+static int sd_uhs2_change_speed(struct mmc_host *host, u32 node_id)
+{
+	struct mmc_command cmd = {0};
+	struct uhs2_command uhs2_cmd = {};
+	u16 header = 0, arg = 0;
+	int err;
+	int timeout = 100;
+
+	/* Change Speed Range at controller side. */
+	if (!host->ops->uhs2_set_reg ||
+	    host->ops->uhs2_set_reg(host, SET_SPEED_B)) {
+		pr_err("%s: %s: UHS2 SET_SPEED fail!\n",
+		       mmc_hostname(host), __func__);
+		return -EIO;
+	}
+
+	err = sd_uhs2_go_dormant(host, false, node_id);
+	if (err) {
+		pr_err("%s: %s: UHS2 GO_DORMANT_STATE fail, err= 0x%x!\n",
+		       mmc_hostname(host), __func__, err);
+		return -EIO;
+	}
+
+	/* restore sd clock */
+	mmc_delay(5);
+	if (host->ops->uhs2_enable_clk)
+		host->ops->uhs2_enable_clk(host);
+
+	/* Enable Normal INT */
+	if (!host->ops->uhs2_set_reg ||
+	    host->ops->uhs2_set_reg(host, ENABLE_INT)) {
+		pr_err("%s: %s: UHS2 ENABLE_INT fail!\n",
+		       mmc_hostname(host), __func__);
+		return -EIO;
+	}
+	
+	/*
+	 * According to UHS-II Addendum Version 1.01, chapter 6.2.3, wait card
+	 * switch to Active State
+	 */
+	header = UHS2_NATIVE_PACKET | UHS2_PACKET_TYPE_CCMD |
+		 host->card->uhs2_config.node_id;
+	arg = ((UHS2_DEV_CONFIG_GEN_SET & 0xFF) << 8) |
+		UHS2_NATIVE_CMD_READ |
+		UHS2_NATIVE_CMD_PLEN_8B |
+		(UHS2_DEV_CONFIG_GEN_SET >> 8);
+	do {
+		sd_uhs2_cmd_assemble(&cmd, &uhs2_cmd,
+				  header, arg,
+				  NULL, 0,
+				  NULL, 0);
+		err = mmc_wait_for_cmd(host, &cmd, 0);
+		if (err) {
+			pr_err("%s: %s: UHS2 CMD send fail, err= 0x%x!\n",
+			       mmc_hostname(host), __func__, err);
+			return -EIO;
+		}
+
+		if (cmd.resp[1] & UHS2_DEV_CONFIG_GEN_SET_CFG_COMPLETE)
+			break;
+
+		timeout--;
+		if (timeout == 0) {
+			pr_err("%s: %s: Not switch to Active in 100 ms\n",
+			       mmc_hostname(host->mmc), __func__);
+			return -EIO;
+		}
+
+		mmc_delay(1);
+	} while (1);
+
 	return 0;
 }
 
@@ -108,8 +724,70 @@  static int sd_uhs2_config_write(struct mmc_host *host, struct mmc_card *card)
  * be set through a legacy CMD6. Note that, the power limit that becomes set,
  * survives a soft reset through the GO_DORMANT_STATE command.
  */
-static int sd_uhs2_legacy_init(struct mmc_host *host, struct mmc_card *card)
+static int sd_uhs2_legacy_init(struct mmc_host *host)
 {
+	int err;
+	u32 ocr, rocr;
+
+	WARN_ON(!host->claimed);
+
+	/* Send CMD0 to reset SD card */
+	mmc_go_idle(host);
+
+	/* Send CMD8 to communicate SD interface operation condition */
+	err = mmc_send_if_cond(host, host->ocr_avail);
+	if (err) {
+		pr_err("%s: %s: SEND_IF_COND fail!\n",
+		       mmc_hostname(host), __func__);
+		return err;
+	}
+
+	/*
+	 * Send host capacity support information and activate card's
+	 * initialization process.
+	 */
+	err = mmc_send_app_op_cond(host, 0, &ocr);
+	if (err) {
+		pr_err("%s: %s: SD_SEND_OP_COND fail!\n",
+		       mmc_hostname(host), __func__);
+		return err;
+	}
+
+	if (host->ocr_avail_sd)
+		host->ocr_avail = host->ocr_avail_sd;
+
+	/*
+	 * Some SD cards claims an out of spec VDD voltage range. Let's treat
+	 * these bits as being in-valid and especially also bit7.
+	 */
+	ocr &= ~0x7FFF;
+	rocr = mmc_select_voltage(host, ocr);
+
+	/*
+	 * Some cards have zero value of rocr in UHS-II mode. Assign host's
+	 * ocr value to rocr.
+	 */
+	if (!rocr) {
+		if (host->ocr_avail) {
+			rocr = host->ocr_avail;
+		} else {
+			pr_err("%s: %s: there is no valid OCR.\n",
+			       mmc_hostname(host), __func__);
+			return -EINVAL;
+		}
+	}
+
+	/*
+	 * Get CID, send relative address, get CSD are the same as legacy
+	 * sd, call mmc_sd_init_card() in sd.c directly
+	 */
+	err = mmc_sd_init_card(host, rocr, NULL);
+	if (err) {
+		pr_err("%s: %s: mmc_sd_init_card() fail!\n",
+		       mmc_hostname(host), __func__);
+		return err;
+	}
+
 	return 0;
 }
 
@@ -124,12 +802,16 @@  static int sd_uhs2_init_card(struct mmc_host *host)
 	int err;
 
 	err = sd_uhs2_dev_init(host);
-	if (err)
+	if (err) {
+		pr_err("%s: UHS2 DEVICE_INIT fail!\n", mmc_hostname(host));
 		return err;
+	}
 
 	err = sd_uhs2_enum(host, &node_id);
-	if (err)
+	if (err) {
+		pr_err("%s: UHS2 ENUMERATE fail!\n", mmc_hostname(host));
 		return err;
+	}
 
 	card = mmc_alloc_card(host, &sd_type);
 	if (IS_ERR(card))
@@ -142,15 +824,26 @@  static int sd_uhs2_init_card(struct mmc_host *host)
 	if (err)
 		goto err;
 
+	/* Change to Speed Range B if it is supported */
+	if (host->flags & MMC_UHS2_SPEED_B) {
+		err = sd_uhs2_change_speed(host, node_id);
+		if (err) {
+			pr_err("%s: %s: UHS2 sd_uhs2_change_speed() fail!\n",
+				mmc_hostname(host), __func__);
+			return err;
+		}
+	}
+
 	err = sd_uhs2_config_write(host, card);
 	if (err)
 		goto err;
 
-	err = sd_uhs2_legacy_init(host, card);
+	host->card = card;
+
+	err = sd_uhs2_legacy_init(host);
 	if (err)
 		goto err;
 
-	host->card = card;
 	return 0;
 
 err:
@@ -217,6 +910,78 @@  static int sd_uhs2_hw_reset(struct mmc_host *host)
 	return 0;
 }
 
+/*
+ * sd_uhs2_prepare_cmd - prepare for SD command packet
+ * @host:	MMC host
+ * @mrq:	MMC request
+ *
+ * Initialize and fill in a header and a payload of SD command packet.
+ * The caller should allocate uhs2_command in host->cmd->uhs2_cmd in
+ * advance.
+ *
+ * Return:	0 on success, non-zero error on failure
+ */
+int sd_uhs2_prepare_cmd(struct mmc_host *host, struct mmc_request *mrq)
+{
+	struct mmc_command *cmd;
+	struct uhs2_command *uhs2_cmd;
+	u16 header = 0, arg = 0;
+	u32 *payload;
+	u8 plen = 0;
+
+	cmd = mrq->cmd;
+	header = host->card->uhs2_config.node_id;
+	if ((cmd->flags & MMC_CMD_MASK) == MMC_CMD_ADTC)
+		header |= UHS2_PACKET_TYPE_DCMD;
+	else
+		header |= UHS2_PACKET_TYPE_CCMD;
+
+	arg = cmd->opcode << UHS2_SD_CMD_INDEX_POS;
+	if (host->flags & MMC_UHS2_APP_CMD) {
+		arg |= UHS2_SD_CMD_APP;
+		host->flags &= ~MMC_UHS2_APP_CMD;
+	}
+
+	uhs2_cmd = cmd->uhs2_cmd;
+	payload = uhs2_cmd->payload;
+	plen = 2; /* at the maximum */
+
+	if ((cmd->flags & MMC_CMD_MASK) == MMC_CMD_ADTC &&
+	    !cmd->uhs2_tmode0_flag) {
+		if (host->flags & MMC_UHS2_2L_HD)
+			arg |= UHS2_DCMD_2L_HD_MODE;
+
+		arg |= UHS2_DCMD_LM_TLEN_EXIST;
+
+		if (cmd->data->blocks == 1 &&
+		    cmd->data->blksz != 512 &&
+		    cmd->opcode != MMC_READ_SINGLE_BLOCK &&
+		    cmd->opcode != MMC_WRITE_BLOCK) {
+			arg |= UHS2_DCMD_TLUM_BYTE_MODE;
+			payload[1] = cpu_to_be32(cmd->data->blksz);
+		} else {
+			payload[1] = cpu_to_be32(cmd->data->blocks);
+		}
+
+		if (cmd->opcode == SD_IO_RW_EXTENDED) {
+			arg &= ~(UHS2_DCMD_LM_TLEN_EXIST |
+				UHS2_DCMD_TLUM_BYTE_MODE |
+				UHS2_NATIVE_DCMD_DAM_IO);
+			payload[1] = 0;
+			plen = 1;
+		}
+	} else {
+		plen = 1;
+	}
+
+	payload[0] = cpu_to_be32(cmd->arg);
+
+	sd_uhs2_cmd_assemble(cmd, uhs2_cmd, header, arg, payload, plen, NULL, 0);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sd_uhs2_prepare_cmd);
+
 static const struct mmc_bus_ops sd_uhs2_ops = {
 	.remove = sd_uhs2_remove,
 	.alive = sd_uhs2_alive,
@@ -254,18 +1019,34 @@  static int sd_uhs2_attach(struct mmc_host *host)
 		goto remove_card;
 
 	mmc_claim_host(host);
+
+	if (host->ops->uhs2_post_attach_sd)
+		host->ops->uhs2_post_attach_sd(host);
+
 	return 0;
 
 remove_card:
-	mmc_remove_card(host->card);
-	host->card = NULL;
+	sd_uhs2_remove(host);
 	mmc_claim_host(host);
-	mmc_detach_bus(host);
+
 err:
+	mmc_detach_bus(host);
 	sd_uhs2_power_off(host);
+	if (host->flags & MMC_UHS2_INITIALIZED)
+		host->flags &= ~MMC_UHS2_INITIALIZED;
+	host->flags &= ~MMC_UHS2_SUPPORT;
 	return err;
 }
 
+/**
+ * mmc_attach_sd_uhs2 - select UHS2 interface
+ * @host: MMC host
+ *
+ * Try to select UHS2 interface and initialize the bus for a given
+ * frequency, @freq.
+ *
+ * Return:	0 on success, non-zero error on failure
+ */
 int mmc_attach_sd_uhs2(struct mmc_host *host)
 {
 	int i, err = 0;
@@ -276,6 +1057,8 @@  int mmc_attach_sd_uhs2(struct mmc_host *host)
 	/* Turn off the legacy SD interface before trying with UHS-II. */
 	mmc_power_off(host);
 
+	host->flags |= MMC_UHS2_SUPPORT;
+
 	/*
 	 * Start UHS-II initialization at 52MHz and possibly make a retry at
 	 * 26MHz according to the spec. It's required that the host driver
@@ -283,9 +1066,15 @@  int mmc_attach_sd_uhs2(struct mmc_host *host)
 	 */
 	for (i = 0; i < ARRAY_SIZE(sd_uhs2_freqs); i++) {
 		host->f_init = sd_uhs2_freqs[i];
+		pr_info("%s: %s: trying to init UHS-II card at %u Hz\n",
+			 mmc_hostname(host), __func__, host->f_init);
+
 		err = sd_uhs2_attach(host);
 		if (!err)
 			break;
+		else
+			pr_err("%s: %s: init card at %u Hz failed\n",
+			       mmc_hostname(host), __func__, host->f_init);
 	}
 
 	return err;