diff mbox series

[8/9] mmc: mmci: sdmmc: add voltage switch functions

Message ID 20200110134823.14882-9-ludovic.barre@st.com (mailing list archive)
State New, archived
Headers show
Series mmc: mmci: sdmmc: add sdr104 support | expand

Commit Message

Ludovic BARRE Jan. 10, 2020, 1:48 p.m. UTC 
To prepare the voltage switch procedure, the VSWITCHEN bit must be
set before sending the cmd11.
To confirm completion of voltage switch, the VSWEND flag must be
checked.

Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
---
 drivers/mmc/host/mmci.h             |  4 +++
 drivers/mmc/host/mmci_stm32_sdmmc.c | 40 ++++++++++++++++++++++++++++-
 2 files changed, 43 insertions(+), 1 deletion(-)

Comments

Ulf Hansson Jan. 24, 2020, 1:16 p.m. UTC | #1 
On Fri, 10 Jan 2020 at 14:49, Ludovic Barre <ludovic.barre@st.com> wrote:
>
> To prepare the voltage switch procedure, the VSWITCHEN bit must be
> set before sending the cmd11.
> To confirm completion of voltage switch, the VSWEND flag must be
> checked.
>
> Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
> ---
>  drivers/mmc/host/mmci.h             |  4 +++
>  drivers/mmc/host/mmci_stm32_sdmmc.c | 40 ++++++++++++++++++++++++++++-
>  2 files changed, 43 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
> index c04a144259a2..3634f98ad2d8 100644
> --- a/drivers/mmc/host/mmci.h
> +++ b/drivers/mmc/host/mmci.h
> @@ -165,6 +165,7 @@
>  /* Extended status bits for the STM32 variants */
>  #define MCI_STM32_BUSYD0       BIT(20)
>  #define MCI_STM32_BUSYD0END    BIT(21)
> +#define MCI_STM32_VSWEND       BIT(25)
>
>  #define MMCICLEAR              0x038
>  #define MCI_CMDCRCFAILCLR      (1 << 0)
> @@ -182,6 +183,9 @@
>  #define MCI_ST_SDIOITC         (1 << 22)
>  #define MCI_ST_CEATAENDC       (1 << 23)
>  #define MCI_ST_BUSYENDC                (1 << 24)
> +/* Extended clear bits for the STM32 variants */
> +#define MCI_STM32_VSWENDC      BIT(25)
> +#define MCI_STM32_CKSTOPC      BIT(26)
>
>  #define MMCIMASK0              0x03c
>  #define MCI_CMDCRCFAILMASK     (1 << 0)
> diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c b/drivers/mmc/host/mmci_stm32_sdmmc.c
> index 10059fa19f4a..9f43cf947c5f 100644
> --- a/drivers/mmc/host/mmci_stm32_sdmmc.c
> +++ b/drivers/mmc/host/mmci_stm32_sdmmc.c
> @@ -263,7 +263,9 @@ static void mmci_sdmmc_set_pwrreg(struct mmci_host *host, unsigned int pwr)
>         struct mmc_ios ios = host->mmc->ios;
>         struct sdmmc_dlyb *dlyb = host->variant_priv;
>
> -       pwr = host->pwr_reg_add;
> +       /* adds OF options and preserves voltage switch bits */
> +       pwr = host->pwr_reg_add |
> +               (host->pwr_reg & (MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
>
>         sdmmc_dlyb_input_ck(dlyb);
>
> @@ -454,6 +456,40 @@ static int sdmmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
>         return sdmmc_dlyb_phase_tuning(host, opcode);
>  }
>
> +static void sdmmc_prep_vswitch(struct mmci_host *host)
> +{
> +       /* clear the voltage switch completion flag */
> +       writel_relaxed(MCI_STM32_VSWENDC, host->base + MMCICLEAR);
> +       /* enable Voltage switch procedure */
> +       mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCHEN);
> +}
> +
> +static int sdmmc_vswitch(struct mmci_host *host, struct mmc_ios *ios)
> +{
> +       unsigned long flags;
> +       u32 status;
> +       int ret = 0;
> +
> +       if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180) {
> +               spin_lock_irqsave(&host->lock, flags);
> +               mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCH);
> +               spin_unlock_irqrestore(&host->lock, flags);
> +
> +               /* wait voltage switch completion while 10ms */
> +               ret = readl_relaxed_poll_timeout(host->base + MMCISTATUS,
> +                                                status,
> +                                                (status & MCI_STM32_VSWEND),
> +                                                10, 10000);
> +
> +               writel_relaxed(MCI_STM32_VSWENDC | MCI_STM32_CKSTOPC,
> +                              host->base + MMCICLEAR);
> +               mmci_write_pwrreg(host, host->pwr_reg &
> +                                 ~(MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
> +       }

Don't you need to manage things when resetting to
MMC_SIGNAL_VOLTAGE_330, which for example happens during a card
removal or at system suspend/resume?

> +
> +       return ret;
> +}
> +
>  static struct mmci_host_ops sdmmc_variant_ops = {
>         .validate_data = sdmmc_idma_validate_data,
>         .prep_data = sdmmc_idma_prep_data,
> @@ -465,6 +501,8 @@ static struct mmci_host_ops sdmmc_variant_ops = {
>         .set_clkreg = mmci_sdmmc_set_clkreg,
>         .set_pwrreg = mmci_sdmmc_set_pwrreg,
>         .busy_complete = sdmmc_busy_complete,
> +       .prep_volt_switch = sdmmc_prep_vswitch,
> +       .volt_switch = sdmmc_vswitch,
>  };
>
>  void sdmmc_variant_init(struct mmci_host *host)
> --
> 2.17.1
>

Kind regards
Uffe
Ludovic BARRE Jan. 27, 2020, 1:50 p.m. UTC | #2 
hi Ulf

Le 1/24/20 à 2:16 PM, Ulf Hansson a écrit :
> On Fri, 10 Jan 2020 at 14:49, Ludovic Barre <ludovic.barre@st.com> wrote:
>>
>> To prepare the voltage switch procedure, the VSWITCHEN bit must be
>> set before sending the cmd11.
>> To confirm completion of voltage switch, the VSWEND flag must be
>> checked.
>>
>> Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
>> ---
>>   drivers/mmc/host/mmci.h             |  4 +++
>>   drivers/mmc/host/mmci_stm32_sdmmc.c | 40 ++++++++++++++++++++++++++++-
>>   2 files changed, 43 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
>> index c04a144259a2..3634f98ad2d8 100644
>> --- a/drivers/mmc/host/mmci.h
>> +++ b/drivers/mmc/host/mmci.h
>> @@ -165,6 +165,7 @@
>>   /* Extended status bits for the STM32 variants */
>>   #define MCI_STM32_BUSYD0       BIT(20)
>>   #define MCI_STM32_BUSYD0END    BIT(21)
>> +#define MCI_STM32_VSWEND       BIT(25)
>>
>>   #define MMCICLEAR              0x038
>>   #define MCI_CMDCRCFAILCLR      (1 << 0)
>> @@ -182,6 +183,9 @@
>>   #define MCI_ST_SDIOITC         (1 << 22)
>>   #define MCI_ST_CEATAENDC       (1 << 23)
>>   #define MCI_ST_BUSYENDC                (1 << 24)
>> +/* Extended clear bits for the STM32 variants */
>> +#define MCI_STM32_VSWENDC      BIT(25)
>> +#define MCI_STM32_CKSTOPC      BIT(26)
>>
>>   #define MMCIMASK0              0x03c
>>   #define MCI_CMDCRCFAILMASK     (1 << 0)
>> diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c b/drivers/mmc/host/mmci_stm32_sdmmc.c
>> index 10059fa19f4a..9f43cf947c5f 100644
>> --- a/drivers/mmc/host/mmci_stm32_sdmmc.c
>> +++ b/drivers/mmc/host/mmci_stm32_sdmmc.c
>> @@ -263,7 +263,9 @@ static void mmci_sdmmc_set_pwrreg(struct mmci_host *host, unsigned int pwr)
>>          struct mmc_ios ios = host->mmc->ios;
>>          struct sdmmc_dlyb *dlyb = host->variant_priv;
>>
>> -       pwr = host->pwr_reg_add;
>> +       /* adds OF options and preserves voltage switch bits */
>> +       pwr = host->pwr_reg_add |
>> +               (host->pwr_reg & (MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
>>
>>          sdmmc_dlyb_input_ck(dlyb);
>>
>> @@ -454,6 +456,40 @@ static int sdmmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
>>          return sdmmc_dlyb_phase_tuning(host, opcode);
>>   }
>>
>> +static void sdmmc_prep_vswitch(struct mmci_host *host)
>> +{
>> +       /* clear the voltage switch completion flag */
>> +       writel_relaxed(MCI_STM32_VSWENDC, host->base + MMCICLEAR);
>> +       /* enable Voltage switch procedure */
>> +       mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCHEN);
>> +}
>> +
>> +static int sdmmc_vswitch(struct mmci_host *host, struct mmc_ios *ios)
>> +{
>> +       unsigned long flags;
>> +       u32 status;
>> +       int ret = 0;
>> +
>> +       if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180) {
>> +               spin_lock_irqsave(&host->lock, flags);
>> +               mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCH);
>> +               spin_unlock_irqrestore(&host->lock, flags);
>> +
>> +               /* wait voltage switch completion while 10ms */
>> +               ret = readl_relaxed_poll_timeout(host->base + MMCISTATUS,
>> +                                                status,
>> +                                                (status & MCI_STM32_VSWEND),
>> +                                                10, 10000);
>> +
>> +               writel_relaxed(MCI_STM32_VSWENDC | MCI_STM32_CKSTOPC,
>> +                              host->base + MMCICLEAR);
>> +               mmci_write_pwrreg(host, host->pwr_reg &
>> +                                 ~(MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
>> +       }
> 
> Don't you need to manage things when resetting to
> MMC_SIGNAL_VOLTAGE_330, which for example happens during a card
> removal or at system suspend/resume?
> 

The VSWITCH sequence is used only for 3.3V to 1.8V.
If there are: card remove | suspend/resume.
The power cycle of sdmmc must be reinitialised
and the reset is mandatory.

>> +
>> +       return ret;
>> +}
>> +
>>   static struct mmci_host_ops sdmmc_variant_ops = {
>>          .validate_data = sdmmc_idma_validate_data,
>>          .prep_data = sdmmc_idma_prep_data,
>> @@ -465,6 +501,8 @@ static struct mmci_host_ops sdmmc_variant_ops = {
>>          .set_clkreg = mmci_sdmmc_set_clkreg,
>>          .set_pwrreg = mmci_sdmmc_set_pwrreg,
>>          .busy_complete = sdmmc_busy_complete,
>> +       .prep_volt_switch = sdmmc_prep_vswitch,
>> +       .volt_switch = sdmmc_vswitch,
>>   };
>>
>>   void sdmmc_variant_init(struct mmci_host *host)
>> --
>> 2.17.1
>>
> 
> Kind regards
> Uffe
>
diff mbox series

Patch

diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index c04a144259a2..3634f98ad2d8 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -165,6 +165,7 @@ 
 /* Extended status bits for the STM32 variants */
 #define MCI_STM32_BUSYD0	BIT(20)
 #define MCI_STM32_BUSYD0END	BIT(21)
+#define MCI_STM32_VSWEND	BIT(25)
 
 #define MMCICLEAR		0x038
 #define MCI_CMDCRCFAILCLR	(1 << 0)
@@ -182,6 +183,9 @@ 
 #define MCI_ST_SDIOITC		(1 << 22)
 #define MCI_ST_CEATAENDC	(1 << 23)
 #define MCI_ST_BUSYENDC		(1 << 24)
+/* Extended clear bits for the STM32 variants */
+#define MCI_STM32_VSWENDC	BIT(25)
+#define MCI_STM32_CKSTOPC	BIT(26)
 
 #define MMCIMASK0		0x03c
 #define MCI_CMDCRCFAILMASK	(1 << 0)
diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c b/drivers/mmc/host/mmci_stm32_sdmmc.c
index 10059fa19f4a..9f43cf947c5f 100644
--- a/drivers/mmc/host/mmci_stm32_sdmmc.c
+++ b/drivers/mmc/host/mmci_stm32_sdmmc.c
@@ -263,7 +263,9 @@  static void mmci_sdmmc_set_pwrreg(struct mmci_host *host, unsigned int pwr)
 	struct mmc_ios ios = host->mmc->ios;
 	struct sdmmc_dlyb *dlyb = host->variant_priv;
 
-	pwr = host->pwr_reg_add;
+	/* adds OF options and preserves voltage switch bits */
+	pwr = host->pwr_reg_add |
+		(host->pwr_reg & (MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
 
 	sdmmc_dlyb_input_ck(dlyb);
 
@@ -454,6 +456,40 @@  static int sdmmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
 	return sdmmc_dlyb_phase_tuning(host, opcode);
 }
 
+static void sdmmc_prep_vswitch(struct mmci_host *host)
+{
+	/* clear the voltage switch completion flag */
+	writel_relaxed(MCI_STM32_VSWENDC, host->base + MMCICLEAR);
+	/* enable Voltage switch procedure */
+	mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCHEN);
+}
+
+static int sdmmc_vswitch(struct mmci_host *host, struct mmc_ios *ios)
+{
+	unsigned long flags;
+	u32 status;
+	int ret = 0;
+
+	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180) {
+		spin_lock_irqsave(&host->lock, flags);
+		mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCH);
+		spin_unlock_irqrestore(&host->lock, flags);
+
+		/* wait voltage switch completion while 10ms */
+		ret = readl_relaxed_poll_timeout(host->base + MMCISTATUS,
+						 status,
+						 (status & MCI_STM32_VSWEND),
+						 10, 10000);
+
+		writel_relaxed(MCI_STM32_VSWENDC | MCI_STM32_CKSTOPC,
+			       host->base + MMCICLEAR);
+		mmci_write_pwrreg(host, host->pwr_reg &
+				  ~(MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
+	}
+
+	return ret;
+}
+
 static struct mmci_host_ops sdmmc_variant_ops = {
 	.validate_data = sdmmc_idma_validate_data,
 	.prep_data = sdmmc_idma_prep_data,
@@ -465,6 +501,8 @@  static struct mmci_host_ops sdmmc_variant_ops = {
 	.set_clkreg = mmci_sdmmc_set_clkreg,
 	.set_pwrreg = mmci_sdmmc_set_pwrreg,
 	.busy_complete = sdmmc_busy_complete,
+	.prep_volt_switch = sdmmc_prep_vswitch,
+	.volt_switch = sdmmc_vswitch,
 };
 
 void sdmmc_variant_init(struct mmci_host *host)