| Message ID | 20191001113830.13028-20-mika.westerberg@linux.intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | thunderbolt: Add support for USB4 | expand |
Hi Mika, > -----Original Message----- > From: Mika Westerberg [mailto:mika.westerberg@linux.intel.com] > Sent: Tuesday, October 01, 2019 4:38 AM > To: linux-usb@vger.kernel.org > Cc: Andreas Noever <andreas.noever@gmail.com>; Jamet, Michael > <michael.jamet@intel.com>; Mika Westerberg > <mika.westerberg@linux.intel.com>; Yehezkel Bernat > <YehezkelShB@gmail.com>; Mani, Rajmohan <rajmohan.mani@intel.com>; > Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>; Lukas > Wunner <lukas@wunner.de>; Greg Kroah-Hartman > <gregkh@linuxfoundation.org>; Alan Stern <stern@rowland.harvard.edu>; > Mario.Limonciello@dell.com; Anthony Wong > <anthony.wong@canonical.com>; linux-kernel@vger.kernel.org > Subject: [RFC PATCH 19/22] thunderbolt: Add support for Time Management > Unit > > From: Rajmohan Mani <rajmohan.mani@intel.com> > > Time Management Unit (TMU) is included in each USB4 router. It is used to > synchronize time across the USB4 fabric. By default when USB4 router is > plugged to the domain, its TMU is turned off. This differs from Thunderbolt (1, > 2 and 3) devices whose TMU is by default configured to bi-directional HiFi > mode. Since time synchronization is needed for proper Display Port tunneling > this means we need to configure the TMU on > USB4 compliant devices. > > The USB4 spec allows some flexibility on how the TMU can be configured. > This makes it possible to enable link power management states (CLx) in certain > topologies, where for example DP tunneling is not used. TMU can also be re- > configured dynamicaly depending on types of tunnels created over the USB4 > fabric. > > In this patch we simply configure the TMU to be in bi-directional HiFi mode. > This way we can tunnel any kind of traffic without need to perform complex > steps to re-configure the domain dynamically. We can add more fine-grained > TMU configuration later on when we start enabling CLx states. > > Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com> > Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com> > Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> > --- > drivers/thunderbolt/Makefile | 2 +- > drivers/thunderbolt/switch.c | 4 + > drivers/thunderbolt/tb.c | 29 +++ > drivers/thunderbolt/tb.h | 47 +++++ > drivers/thunderbolt/tb_regs.h | 20 ++ > drivers/thunderbolt/tmu.c | 380 ++++++++++++++++++++++++++++++++++ > 6 files changed, 481 insertions(+), 1 deletion(-) create mode 100644 > drivers/thunderbolt/tmu.c > > diff --git a/drivers/thunderbolt/Makefile b/drivers/thunderbolt/Makefile index > c0b2fd73dfbd..2014bc840b06 100644 > --- a/drivers/thunderbolt/Makefile > +++ b/drivers/thunderbolt/Makefile > @@ -1,4 +1,4 @@ > # SPDX-License-Identifier: GPL-2.0-only obj-${CONFIG_THUNDERBOLT} := > thunderbolt.o thunderbolt-objs := nhi.o nhi_ops.o ctl.o tb.o switch.o cap.o > path.o tunnel.o eeprom.o -thunderbolt-objs += domain.o dma_port.o icm.o > property.o xdomain.o lc.o usb4.o > +thunderbolt-objs += domain.o dma_port.o icm.o property.o xdomain.o lc.o > +tmu.o usb4.o > diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index > 2ccd1004920e..58e3f54ddbb9 100644 > --- a/drivers/thunderbolt/switch.c > +++ b/drivers/thunderbolt/switch.c > @@ -2278,6 +2278,10 @@ int tb_switch_add(struct tb_switch *sw) > ret = tb_switch_update_link_attributes(sw); > if (ret) > return ret; > + > + ret = tb_switch_tmu_init(sw); > + if (ret) > + return ret; > } > > ret = device_add(&sw->dev); > diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c index > 24e37e47dc48..f2868c125637 100644 > --- a/drivers/thunderbolt/tb.c > +++ b/drivers/thunderbolt/tb.c > @@ -161,6 +161,25 @@ static void tb_scan_xdomain(struct tb_port *port) > } > } > > +static int tb_enable_tmu(struct tb_switch *sw) { > + int ret; > + > + /* If it is already enabled in correct mode, don't touch it */ > + if (tb_switch_tmu_is_enabled(sw)) > + return 0; > + > + ret = tb_switch_tmu_disable(sw); > + if (ret) > + return ret; > + > + ret = tb_switch_tmu_post_time(sw); > + if (ret) > + return ret; > + > + return tb_switch_tmu_enable(sw); > +} > + > static void tb_scan_port(struct tb_port *port); > > /** > @@ -263,6 +282,9 @@ static void tb_scan_port(struct tb_port *port) > if (tb_switch_lane_bonding_enable(sw)) > tb_sw_warn(sw, "failed to enable lane bonding\n"); > > + if (tb_enable_tmu(sw)) > + tb_sw_warn(sw, "failed to enable TMU\n"); > + > tb_scan_switch(sw); > } > > @@ -713,6 +735,7 @@ static void tb_handle_hotplug(struct work_struct > *work) > tb_sw_set_unplugged(port->remote->sw); > tb_free_invalid_tunnels(tb); > tb_remove_dp_resources(port->remote->sw); > + tb_switch_tmu_disable(port->remote->sw); > tb_switch_lane_bonding_disable(port->remote->sw); > tb_switch_remove(port->remote->sw); > port->remote = NULL; > @@ -860,6 +883,9 @@ static int tb_start(struct tb *tb) > return ret; > } > > + /* Enable TMU if it is off */ > + if (!tb_switch_tmu_is_enabled(tb->root_switch)) To be consistent with the implementation of tb_switch_tmu_disable(), should we move the above check inside tb_switch_tmu_enable()? > + tb_switch_tmu_enable(tb->root_switch); > /* Full scan to discover devices added before the driver was loaded. */ > tb_scan_switch(tb->root_switch); > /* Find out tunnels created by the boot firmware */ @@ -891,6 +917,9 > @@ static void tb_restore_children(struct tb_switch *sw) { > int i; > > + if (tb_enable_tmu(sw)) > + tb_sw_warn(sw, "failed to restore TMU configuration\n"); > + > tb_switch_for_each_remote_port(sw, i) { > struct tb_port *port = &sw->ports[i]; > > diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h index > 1488382066fd..087fd6d6ef9a 100644 > --- a/drivers/thunderbolt/tb.h > +++ b/drivers/thunderbolt/tb.h > @@ -46,6 +46,38 @@ struct tb_switch_nvm { > #define TB_SWITCH_MAX_DEPTH 6 > #define USB4_SWITCH_MAX_DEPTH 5 > > +/** > + * enum tb_switch_tmu_rate - TMU refresh rate > + * @TB_SWITCH_TMU_RATE_OFF: %0 (Disable Time Sync handshake) > + * @TB_SWITCH_TMU_RATE_HIFI: %16 us time interval between successive > + * transmission of the Delay Request TSNOS > + * (Time Sync Notification Ordered Set) on a Link > + * @TB_SWITCH_TMU_RATE_NORMAL: %1 ms time interval between > successive > + * transmission of the Delay Request TSNOS on > + * a Link > + */ > +enum tb_switch_tmu_rate { > + TB_SWITCH_TMU_RATE_OFF = 0, > + TB_SWITCH_TMU_RATE_HIFI = 16, > + TB_SWITCH_TMU_RATE_NORMAL = 1000, > +}; > + > +/** > + * struct tb_switch_tmu - Structure holding switch TMU configuration > + * @cap: Offset to the TMU capability (%0 if not found) > + * @has_ucap: Does the switch support uni-directional mode > + * @rate: TMU refresh rate related to upstream switch. In case of root > + * switch this holds the domain rate. > + * @unidirectional: Is the TMU in uni-directional or bi-directional mode > + * related to upstream switch. Don't case for root switch. > + */ > +struct tb_switch_tmu { > + int cap; > + bool has_ucap; > + enum tb_switch_tmu_rate rate; > + bool unidirectional; > +}; > + > /** > * struct tb_switch - a thunderbolt switch > * @dev: Device for the switch > @@ -55,6 +87,7 @@ struct tb_switch_nvm { > * mailbox this will hold the pointer to that (%NULL > * otherwise). If set it also means the switch has > * upgradeable NVM. > + * @tmu: The switch TMU configuration > * @tb: Pointer to the domain the switch belongs to > * @uid: Unique ID of the switch > * @uuid: UUID of the switch (or %NULL if not supported) @@ -93,6 +126,7 > @@ struct tb_switch { > struct tb_regs_switch_header config; > struct tb_port *ports; > struct tb_dma_port *dma_port; > + struct tb_switch_tmu tmu; > struct tb *tb; > u64 uid; > uuid_t *uuid; > @@ -129,6 +163,7 @@ struct tb_switch { > * @remote: Remote port (%NULL if not connected) > * @xdomain: Remote host (%NULL if not connected) > * @cap_phy: Offset, zero if not found > + * @cap_tmu: Offset of the adapter specific TMU capability (%0 if not > + present) > * @cap_adap: Offset of the adapter specific capability (%0 if not present) > * @cap_usb4: Offset to the USB4 port capability (%0 if not present) > * @port: Port number on switch > @@ -147,6 +182,7 @@ struct tb_port { > struct tb_port *remote; > struct tb_xdomain *xdomain; > int cap_phy; > + int cap_tmu; > int cap_adap; > int cap_usb4; > u8 port; > @@ -696,6 +732,17 @@ bool tb_switch_query_dp_resource(struct tb_switch > *sw, struct tb_port *in); int tb_switch_alloc_dp_resource(struct tb_switch > *sw, struct tb_port *in); void tb_switch_dealloc_dp_resource(struct tb_switch > *sw, struct tb_port *in); > > +int tb_switch_tmu_init(struct tb_switch *sw); int > +tb_switch_tmu_post_time(struct tb_switch *sw); int > +tb_switch_tmu_disable(struct tb_switch *sw); int > +tb_switch_tmu_enable(struct tb_switch *sw); > + > +static inline bool tb_switch_tmu_is_enabled(const struct tb_switch *sw) > +{ > + return sw->tmu.rate == TB_SWITCH_TMU_RATE_HIFI && > + !sw->tmu.unidirectional; > +} > + > int tb_wait_for_port(struct tb_port *port, bool wait_if_unplugged); int > tb_port_add_nfc_credits(struct tb_port *port, int credits); int > tb_port_set_initial_credits(struct tb_port *port, u32 credits); diff --git > a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h index > 47f73f992412..ec1a5d1f7c94 100644 > --- a/drivers/thunderbolt/tb_regs.h > +++ b/drivers/thunderbolt/tb_regs.h > @@ -26,6 +26,7 @@ > #define TB_MAX_CONFIG_RW_LENGTH 60 > > enum tb_switch_cap { > + TB_SWITCH_CAP_TMU = 0x03, > TB_SWITCH_CAP_VSE = 0x05, > }; > > @@ -195,6 +196,21 @@ struct tb_regs_switch_header { > #define ROUTER_CS_26_ONS BIT(30) > #define ROUTER_CS_26_OV BIT(31) > > +/* Router TMU configuration */ > +#define TMU_RTR_CS_0 0x00 > +#define TMU_RTR_CS_0_TD BIT(27) > +#define TMU_RTR_CS_0_UCAP BIT(30) > +#define TMU_RTR_CS_1 0x01 > +#define TMU_RTR_CS_1_LOCAL_TIME_NS_MASK GENMASK(31, > 16) > +#define TMU_RTR_CS_1_LOCAL_TIME_NS_SHIFT 16 > +#define TMU_RTR_CS_2 0x02 > +#define TMU_RTR_CS_3 0x03 > +#define TMU_RTR_CS_3_LOCAL_TIME_NS_MASK GENMASK(15, > 0) > +#define TMU_RTR_CS_3_TS_PACKET_INTERVAL_MASK GENMASK(31, > 16) > +#define TMU_RTR_CS_3_TS_PACKET_INTERVAL_SHIFT 16 > +#define TMU_RTR_CS_22 0x16 > +#define TMU_RTR_CS_24 0x18 > + > enum tb_port_type { > TB_TYPE_INACTIVE = 0x000000, > TB_TYPE_PORT = 0x000001, > @@ -248,6 +264,10 @@ struct tb_regs_port_header { > #define ADP_CS_5_LCA_MASK GENMASK(28, 22) > #define ADP_CS_5_LCA_SHIFT 22 > > +/* TMU adapter registers */ > +#define TMU_ADP_CS_3 0x03 > +#define TMU_ADP_CS_3_UDM BIT(29) > + > /* Lane adapter registers */ > #define LANE_ADP_CS_0 0x00 > #define LANE_ADP_CS_0_SUPPORTED_WIDTH_MASK GENMASK(25, 20) > diff --git a/drivers/thunderbolt/tmu.c b/drivers/thunderbolt/tmu.c new file > mode 100644 index 000000000000..d6314f6b20c7 > --- /dev/null > +++ b/drivers/thunderbolt/tmu.c > @@ -0,0 +1,380 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Thunderbolt Time Management Unit (TMU) support > + * > + * Copyright (C) 2019, Intel Corporation > + * Authors: Mika Westerberg <mika.westerberg@linux.intel.com> > + * Rajmohan Mani <rajmohan.mani@intel.com> > + */ > + > +#include <linux/delay.h> > + > +#include "tb.h" > + > +static const char *tb_switch_tmu_mode_name(const struct tb_switch *sw) > +{ > + bool root_switch = !tb_route(sw); > + > + switch (sw->tmu.rate) { > + case TB_SWITCH_TMU_RATE_OFF: > + return "off"; > + > + case TB_SWITCH_TMU_RATE_HIFI: > + /* Root switch does not have upstream directionality */ > + if (root_switch) > + return "HiFi"; > + if (sw->tmu.unidirectional) > + return "uni-directional, HiFi"; > + return "bi-directional, HiFi"; > + > + case TB_SWITCH_TMU_RATE_NORMAL: > + if (root_switch) > + return "normal"; > + return "uni-directional, normal"; > + > + default: > + return "unknown"; > + } > +} > + > +static bool tb_switch_tmu_ucap_supported(struct tb_switch *sw) { > + int ret; > + u32 val; > + > + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, > + sw->tmu.cap + TMU_RTR_CS_0, 1); > + if (ret) > + return false; > + > + return !!(val & TMU_RTR_CS_0_UCAP); > +} > + > +static int tb_switch_tmu_rate_read(struct tb_switch *sw) { > + int ret; > + u32 val; > + > + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, > + sw->tmu.cap + TMU_RTR_CS_3, 1); > + if (ret) > + return ret; > + > + val >>= TMU_RTR_CS_3_TS_PACKET_INTERVAL_SHIFT; > + return val; > +} > + > +static int tb_switch_tmu_rate_write(struct tb_switch *sw, int rate) { > + int ret; > + u32 val; > + > + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, > + sw->tmu.cap + TMU_RTR_CS_3, 1); > + if (ret) > + return ret; > + > + val &= ~TMU_RTR_CS_3_TS_PACKET_INTERVAL_MASK; > + val |= rate << TMU_RTR_CS_3_TS_PACKET_INTERVAL_SHIFT; > + > + return tb_sw_write(sw, &val, TB_CFG_SWITCH, > + sw->tmu.cap + TMU_RTR_CS_3, 1); > +} > + > +static int tb_port_tmu_write(struct tb_port *port, u8 offset, u32 mask, > + u32 value) > +{ > + u32 data; > + int ret; > + > + ret = tb_port_read(port, &data, TB_CFG_PORT, port->cap_tmu + > offset, 1); > + if (ret) > + return ret; > + > + data &= ~mask; > + data |= value; > + > + return tb_port_write(port, &data, TB_CFG_PORT, > + port->cap_tmu + offset, 1); > +} > + > +static int tb_port_tmu_set_unidirectional(struct tb_port *port, > + bool unidirectional) > +{ > + u32 val; > + > + if (!port->sw->tmu.has_ucap) > + return 0; > + > + val = unidirectional ? TMU_ADP_CS_3_UDM : 0; > + return tb_port_tmu_write(port, TMU_ADP_CS_3, > TMU_ADP_CS_3_UDM, val); } > + > +static inline int tb_port_tmu_unidirectional_disable(struct tb_port > +*port) { > + return tb_port_tmu_set_unidirectional(port, false); } > + > +static bool tb_port_tmu_is_unidirectional(struct tb_port *port) { > + int ret; > + u32 val; > + > + ret = tb_port_read(port, &val, TB_CFG_PORT, > + port->cap_tmu + TMU_ADP_CS_3, 1); > + if (ret) > + return false; > + > + return val & TMU_ADP_CS_3_UDM; > +} > + > +static int tb_switch_tmu_set_time_disruption(struct tb_switch *sw, bool > +set) { > + int ret; > + u32 val; > + > + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, > + sw->tmu.cap + TMU_RTR_CS_0, 1); > + if (ret) > + return ret; > + > + if (set) > + val |= TMU_RTR_CS_0_TD; > + else > + val &= ~TMU_RTR_CS_0_TD; > + > + return tb_sw_write(sw, &val, TB_CFG_SWITCH, > + sw->tmu.cap + TMU_RTR_CS_0, 1); > +} > + > +/** > + * tb_switch_tmu_init() - Initialize switch TMU structures > + * @sw: Switch to initialized > + * > + * This function must be called before other TMU related functions to > + * makes the internal structures are filled in correctly. Does not > + * change any hardware configuration. > + */ > +int tb_switch_tmu_init(struct tb_switch *sw) { > + int ret, i; > + > + if (tb_switch_is_icm(sw)) > + return 0; > + > + ret = tb_switch_find_cap(sw, TB_SWITCH_CAP_TMU); > + if (ret > 0) > + sw->tmu.cap = ret; > + > + tb_switch_for_each_port(sw, i) { > + struct tb_port *port = &sw->ports[i]; > + int cap; > + > + cap = tb_port_find_cap(port, TB_PORT_CAP_TIME1); > + if (cap > 0) > + port->cap_tmu = cap; > + } > + > + ret = tb_switch_tmu_rate_read(sw); > + if (ret < 0) > + return ret; > + > + sw->tmu.rate = ret; > + > + sw->tmu.has_ucap = tb_switch_tmu_ucap_supported(sw); > + if (sw->tmu.has_ucap) { > + tb_sw_dbg(sw, "TMU: supports uni-directional mode\n"); > + > + if (tb_route(sw)) { > + struct tb_port *up = tb_upstream_port(sw); > + > + sw->tmu.unidirectional = > + tb_port_tmu_is_unidirectional(up); > + } > + } else { > + sw->tmu.unidirectional = false; > + } > + > + tb_sw_dbg(sw, "TMU: current mode: %s\n", > tb_switch_tmu_mode_name(sw)); > + return 0; > +} > + > +/** > + * tb_switch_tmu_post_time() - Update switch local time > + * @sw: Switch whose time to update > + * > + * Updates switch local time using time posting procedure. > + */ > +int tb_switch_tmu_post_time(struct tb_switch *sw) { > + unsigned int post_local_time_offset, post_time_offset; > + struct tb_switch *root_switch = sw->tb->root_switch; > + u64 hi, mid, lo, local_time, post_time; > + int i, ret, retries = 100; > + u32 gm_local_time[3]; > + > + if (!tb_route(sw)) > + return 0; > + > + if (!tb_switch_is_usb4(sw)) > + return 0; > + > + /* Need to be able to read the grand master time */ > + if (!root_switch->tmu.cap) > + return 0; > + > + ret = tb_sw_read(root_switch, gm_local_time, TB_CFG_SWITCH, > + root_switch->tmu.cap + TMU_RTR_CS_1, > + ARRAY_SIZE(gm_local_time)); > + if (ret) > + return ret; > + > + for (i = 0; i < ARRAY_SIZE(gm_local_time); i++) > + tb_sw_dbg(root_switch, "local_time[%d]=0x%08x\n", i, > + gm_local_time[i]); > + > + /* Convert to nanoseconds (drop fractional part) */ > + hi = gm_local_time[2] & TMU_RTR_CS_3_LOCAL_TIME_NS_MASK; > + mid = gm_local_time[1]; > + lo = (gm_local_time[0] & TMU_RTR_CS_1_LOCAL_TIME_NS_MASK) >> > + TMU_RTR_CS_1_LOCAL_TIME_NS_SHIFT; > + local_time = hi << 48 | mid << 16 | lo; > + > + /* Tell the switch that time sync is disrupted for a while */ > + ret = tb_switch_tmu_set_time_disruption(sw, true); > + if (ret) > + return ret; > + > + post_local_time_offset = sw->tmu.cap + TMU_RTR_CS_22; > + post_time_offset = sw->tmu.cap + TMU_RTR_CS_24; > + > + /* > + * Write the Grandmaster time to the Post Local Time registers > + * of the new switch. > + */ > + ret = tb_sw_write(sw, &local_time, TB_CFG_SWITCH, > + post_local_time_offset, 2); > + if (ret) > + goto out; > + > + /* > + * Have the new switch update its local time (by writing 1 to > + * the post_time registers) and wait for the completion of the > + * same (post_time register becomes 0). This means the time has > + * been converged properly. > + */ > + post_time = 1; > + > + ret = tb_sw_write(sw, &post_time, TB_CFG_SWITCH, post_time_offset, > 2); > + if (ret) > + goto out; > + > + do { > + usleep_range(5, 10); > + ret = tb_sw_read(sw, &post_time, TB_CFG_SWITCH, > + post_time_offset, 2); > + if (ret) > + goto out; > + } while (--retries && post_time); > + > + if (!retries) { > + ret = -ETIMEDOUT; > + goto out; > + } > + > + tb_sw_dbg(sw, "TMU: updated local time to %#llx\n", local_time); > + > +out: > + tb_switch_tmu_set_time_disruption(sw, false); > + return ret; > +} > + > +/** > + * tb_switch_tmu_disable() - Disable TMU of a switch > + * @sw: Switch whose TMU to disable > + * > + * Turns off TMU of @sw if it is enabled. If not enabled does nothing. > + */ > +int tb_switch_tmu_disable(struct tb_switch *sw) { > + int ret; > + > + if (!tb_switch_is_usb4(sw)) > + return 0; > + > + /* Already disabled? */ > + if (sw->tmu.rate == TB_SWITCH_TMU_RATE_OFF) > + return 0; > + > + if (sw->tmu.unidirectional) { > + struct tb_switch *parent = tb_switch_parent(sw); > + struct tb_port *up, *down; > + > + up = tb_upstream_port(sw); > + down = tb_port_at(tb_route(sw), parent); > + > + /* The switch may be unplugged so ignore any errors */ > + tb_port_tmu_unidirectional_disable(up); > + ret = tb_port_tmu_unidirectional_disable(down); > + if (ret) > + return ret; > + } > + > + tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_OFF); > + > + sw->tmu.unidirectional = false; > + sw->tmu.rate = TB_SWITCH_TMU_RATE_OFF; > + > + tb_sw_dbg(sw, "TMU: disabled\n"); > + return 0; > +} > + > +/** > + * tb_switch_tmu_enable() - Enable TMU on a switch > + * @sw: Switch whose TMU to enable > + * > + * Enables TMU of a switch to be in bi-directional, HiFi mode. In this > +mode > + * all tunneling should work. > + */ > +int tb_switch_tmu_enable(struct tb_switch *sw) { > + int ret; > + > + if (!tb_switch_is_usb4(sw)) > + return 0; > + > + ret = tb_switch_tmu_set_time_disruption(sw, true); > + if (ret) > + return ret; > + > + /* Change mode to bi-directional */ > + if (tb_route(sw) && sw->tmu.unidirectional) { > + struct tb_switch *parent = tb_switch_parent(sw); > + struct tb_port *up, *down; > + > + up = tb_upstream_port(sw); > + down = tb_port_at(tb_route(sw), parent); > + > + ret = tb_port_tmu_unidirectional_disable(down); > + if (ret) > + return ret; > + > + ret = tb_switch_tmu_rate_write(sw, > TB_SWITCH_TMU_RATE_HIFI); > + if (ret) > + return ret; > + > + ret = tb_port_tmu_unidirectional_disable(up); > + if (ret) > + return ret; > + } else { > + ret = tb_switch_tmu_rate_write(sw, > TB_SWITCH_TMU_RATE_HIFI); > + if (ret) > + return ret; > + } > + > + sw->tmu.unidirectional = false; > + sw->tmu.rate = TB_SWITCH_TMU_RATE_HIFI; > + tb_sw_dbg(sw, "TMU: mode set to: %s\n", > tb_switch_tmu_mode_name(sw)); > + > + return tb_switch_tmu_set_time_disruption(sw, false); } > -- > 2.23.0
On Wed, Oct 02, 2019 at 04:52:06PM +0000, Mani, Rajmohan wrote: > > + /* Enable TMU if it is off */ > > + if (!tb_switch_tmu_is_enabled(tb->root_switch)) > > To be consistent with the implementation of tb_switch_tmu_disable(), should we > move the above check inside tb_switch_tmu_enable()? Yes, I think it makes sense.
diff --git a/drivers/thunderbolt/Makefile b/drivers/thunderbolt/Makefile index c0b2fd73dfbd..2014bc840b06 100644 --- a/drivers/thunderbolt/Makefile +++ b/drivers/thunderbolt/Makefile @@ -1,4 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only obj-${CONFIG_THUNDERBOLT} := thunderbolt.o thunderbolt-objs := nhi.o nhi_ops.o ctl.o tb.o switch.o cap.o path.o tunnel.o eeprom.o -thunderbolt-objs += domain.o dma_port.o icm.o property.o xdomain.o lc.o usb4.o +thunderbolt-objs += domain.o dma_port.o icm.o property.o xdomain.o lc.o tmu.o usb4.o diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index 2ccd1004920e..58e3f54ddbb9 100644 --- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -2278,6 +2278,10 @@ int tb_switch_add(struct tb_switch *sw) ret = tb_switch_update_link_attributes(sw); if (ret) return ret; + + ret = tb_switch_tmu_init(sw); + if (ret) + return ret; } ret = device_add(&sw->dev); diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c index 24e37e47dc48..f2868c125637 100644 --- a/drivers/thunderbolt/tb.c +++ b/drivers/thunderbolt/tb.c @@ -161,6 +161,25 @@ static void tb_scan_xdomain(struct tb_port *port) } } +static int tb_enable_tmu(struct tb_switch *sw) +{ + int ret; + + /* If it is already enabled in correct mode, don't touch it */ + if (tb_switch_tmu_is_enabled(sw)) + return 0; + + ret = tb_switch_tmu_disable(sw); + if (ret) + return ret; + + ret = tb_switch_tmu_post_time(sw); + if (ret) + return ret; + + return tb_switch_tmu_enable(sw); +} + static void tb_scan_port(struct tb_port *port); /** @@ -263,6 +282,9 @@ static void tb_scan_port(struct tb_port *port) if (tb_switch_lane_bonding_enable(sw)) tb_sw_warn(sw, "failed to enable lane bonding\n"); + if (tb_enable_tmu(sw)) + tb_sw_warn(sw, "failed to enable TMU\n"); + tb_scan_switch(sw); } @@ -713,6 +735,7 @@ static void tb_handle_hotplug(struct work_struct *work) tb_sw_set_unplugged(port->remote->sw); tb_free_invalid_tunnels(tb); tb_remove_dp_resources(port->remote->sw); + tb_switch_tmu_disable(port->remote->sw); tb_switch_lane_bonding_disable(port->remote->sw); tb_switch_remove(port->remote->sw); port->remote = NULL; @@ -860,6 +883,9 @@ static int tb_start(struct tb *tb) return ret; } + /* Enable TMU if it is off */ + if (!tb_switch_tmu_is_enabled(tb->root_switch)) + tb_switch_tmu_enable(tb->root_switch); /* Full scan to discover devices added before the driver was loaded. */ tb_scan_switch(tb->root_switch); /* Find out tunnels created by the boot firmware */ @@ -891,6 +917,9 @@ static void tb_restore_children(struct tb_switch *sw) { int i; + if (tb_enable_tmu(sw)) + tb_sw_warn(sw, "failed to restore TMU configuration\n"); + tb_switch_for_each_remote_port(sw, i) { struct tb_port *port = &sw->ports[i]; diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h index 1488382066fd..087fd6d6ef9a 100644 --- a/drivers/thunderbolt/tb.h +++ b/drivers/thunderbolt/tb.h @@ -46,6 +46,38 @@ struct tb_switch_nvm { #define TB_SWITCH_MAX_DEPTH 6 #define USB4_SWITCH_MAX_DEPTH 5 +/** + * enum tb_switch_tmu_rate - TMU refresh rate + * @TB_SWITCH_TMU_RATE_OFF: %0 (Disable Time Sync handshake) + * @TB_SWITCH_TMU_RATE_HIFI: %16 us time interval between successive + * transmission of the Delay Request TSNOS + * (Time Sync Notification Ordered Set) on a Link + * @TB_SWITCH_TMU_RATE_NORMAL: %1 ms time interval between successive + * transmission of the Delay Request TSNOS on + * a Link + */ +enum tb_switch_tmu_rate { + TB_SWITCH_TMU_RATE_OFF = 0, + TB_SWITCH_TMU_RATE_HIFI = 16, + TB_SWITCH_TMU_RATE_NORMAL = 1000, +}; + +/** + * struct tb_switch_tmu - Structure holding switch TMU configuration + * @cap: Offset to the TMU capability (%0 if not found) + * @has_ucap: Does the switch support uni-directional mode + * @rate: TMU refresh rate related to upstream switch. In case of root + * switch this holds the domain rate. + * @unidirectional: Is the TMU in uni-directional or bi-directional mode + * related to upstream switch. Don't case for root switch. + */ +struct tb_switch_tmu { + int cap; + bool has_ucap; + enum tb_switch_tmu_rate rate; + bool unidirectional; +}; + /** * struct tb_switch - a thunderbolt switch * @dev: Device for the switch @@ -55,6 +87,7 @@ struct tb_switch_nvm { * mailbox this will hold the pointer to that (%NULL * otherwise). If set it also means the switch has * upgradeable NVM. + * @tmu: The switch TMU configuration * @tb: Pointer to the domain the switch belongs to * @uid: Unique ID of the switch * @uuid: UUID of the switch (or %NULL if not supported) @@ -93,6 +126,7 @@ struct tb_switch { struct tb_regs_switch_header config; struct tb_port *ports; struct tb_dma_port *dma_port; + struct tb_switch_tmu tmu; struct tb *tb; u64 uid; uuid_t *uuid; @@ -129,6 +163,7 @@ struct tb_switch { * @remote: Remote port (%NULL if not connected) * @xdomain: Remote host (%NULL if not connected) * @cap_phy: Offset, zero if not found + * @cap_tmu: Offset of the adapter specific TMU capability (%0 if not present) * @cap_adap: Offset of the adapter specific capability (%0 if not present) * @cap_usb4: Offset to the USB4 port capability (%0 if not present) * @port: Port number on switch @@ -147,6 +182,7 @@ struct tb_port { struct tb_port *remote; struct tb_xdomain *xdomain; int cap_phy; + int cap_tmu; int cap_adap; int cap_usb4; u8 port; @@ -696,6 +732,17 @@ bool tb_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in); int tb_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in); void tb_switch_dealloc_dp_resource(struct tb_switch *sw, struct tb_port *in); +int tb_switch_tmu_init(struct tb_switch *sw); +int tb_switch_tmu_post_time(struct tb_switch *sw); +int tb_switch_tmu_disable(struct tb_switch *sw); +int tb_switch_tmu_enable(struct tb_switch *sw); + +static inline bool tb_switch_tmu_is_enabled(const struct tb_switch *sw) +{ + return sw->tmu.rate == TB_SWITCH_TMU_RATE_HIFI && + !sw->tmu.unidirectional; +} + int tb_wait_for_port(struct tb_port *port, bool wait_if_unplugged); int tb_port_add_nfc_credits(struct tb_port *port, int credits); int tb_port_set_initial_credits(struct tb_port *port, u32 credits); diff --git a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h index 47f73f992412..ec1a5d1f7c94 100644 --- a/drivers/thunderbolt/tb_regs.h +++ b/drivers/thunderbolt/tb_regs.h @@ -26,6 +26,7 @@ #define TB_MAX_CONFIG_RW_LENGTH 60 enum tb_switch_cap { + TB_SWITCH_CAP_TMU = 0x03, TB_SWITCH_CAP_VSE = 0x05, }; @@ -195,6 +196,21 @@ struct tb_regs_switch_header { #define ROUTER_CS_26_ONS BIT(30) #define ROUTER_CS_26_OV BIT(31) +/* Router TMU configuration */ +#define TMU_RTR_CS_0 0x00 +#define TMU_RTR_CS_0_TD BIT(27) +#define TMU_RTR_CS_0_UCAP BIT(30) +#define TMU_RTR_CS_1 0x01 +#define TMU_RTR_CS_1_LOCAL_TIME_NS_MASK GENMASK(31, 16) +#define TMU_RTR_CS_1_LOCAL_TIME_NS_SHIFT 16 +#define TMU_RTR_CS_2 0x02 +#define TMU_RTR_CS_3 0x03 +#define TMU_RTR_CS_3_LOCAL_TIME_NS_MASK GENMASK(15, 0) +#define TMU_RTR_CS_3_TS_PACKET_INTERVAL_MASK GENMASK(31, 16) +#define TMU_RTR_CS_3_TS_PACKET_INTERVAL_SHIFT 16 +#define TMU_RTR_CS_22 0x16 +#define TMU_RTR_CS_24 0x18 + enum tb_port_type { TB_TYPE_INACTIVE = 0x000000, TB_TYPE_PORT = 0x000001, @@ -248,6 +264,10 @@ struct tb_regs_port_header { #define ADP_CS_5_LCA_MASK GENMASK(28, 22) #define ADP_CS_5_LCA_SHIFT 22 +/* TMU adapter registers */ +#define TMU_ADP_CS_3 0x03 +#define TMU_ADP_CS_3_UDM BIT(29) + /* Lane adapter registers */ #define LANE_ADP_CS_0 0x00 #define LANE_ADP_CS_0_SUPPORTED_WIDTH_MASK GENMASK(25, 20) diff --git a/drivers/thunderbolt/tmu.c b/drivers/thunderbolt/tmu.c new file mode 100644 index 000000000000..d6314f6b20c7 --- /dev/null +++ b/drivers/thunderbolt/tmu.c @@ -0,0 +1,380 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Thunderbolt Time Management Unit (TMU) support + * + * Copyright (C) 2019, Intel Corporation + * Authors: Mika Westerberg <mika.westerberg@linux.intel.com> + * Rajmohan Mani <rajmohan.mani@intel.com> + */ + +#include <linux/delay.h> + +#include "tb.h" + +static const char *tb_switch_tmu_mode_name(const struct tb_switch *sw) +{ + bool root_switch = !tb_route(sw); + + switch (sw->tmu.rate) { + case TB_SWITCH_TMU_RATE_OFF: + return "off"; + + case TB_SWITCH_TMU_RATE_HIFI: + /* Root switch does not have upstream directionality */ + if (root_switch) + return "HiFi"; + if (sw->tmu.unidirectional) + return "uni-directional, HiFi"; + return "bi-directional, HiFi"; + + case TB_SWITCH_TMU_RATE_NORMAL: + if (root_switch) + return "normal"; + return "uni-directional, normal"; + + default: + return "unknown"; + } +} + +static bool tb_switch_tmu_ucap_supported(struct tb_switch *sw) +{ + int ret; + u32 val; + + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, + sw->tmu.cap + TMU_RTR_CS_0, 1); + if (ret) + return false; + + return !!(val & TMU_RTR_CS_0_UCAP); +} + +static int tb_switch_tmu_rate_read(struct tb_switch *sw) +{ + int ret; + u32 val; + + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, + sw->tmu.cap + TMU_RTR_CS_3, 1); + if (ret) + return ret; + + val >>= TMU_RTR_CS_3_TS_PACKET_INTERVAL_SHIFT; + return val; +} + +static int tb_switch_tmu_rate_write(struct tb_switch *sw, int rate) +{ + int ret; + u32 val; + + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, + sw->tmu.cap + TMU_RTR_CS_3, 1); + if (ret) + return ret; + + val &= ~TMU_RTR_CS_3_TS_PACKET_INTERVAL_MASK; + val |= rate << TMU_RTR_CS_3_TS_PACKET_INTERVAL_SHIFT; + + return tb_sw_write(sw, &val, TB_CFG_SWITCH, + sw->tmu.cap + TMU_RTR_CS_3, 1); +} + +static int tb_port_tmu_write(struct tb_port *port, u8 offset, u32 mask, + u32 value) +{ + u32 data; + int ret; + + ret = tb_port_read(port, &data, TB_CFG_PORT, port->cap_tmu + offset, 1); + if (ret) + return ret; + + data &= ~mask; + data |= value; + + return tb_port_write(port, &data, TB_CFG_PORT, + port->cap_tmu + offset, 1); +} + +static int tb_port_tmu_set_unidirectional(struct tb_port *port, + bool unidirectional) +{ + u32 val; + + if (!port->sw->tmu.has_ucap) + return 0; + + val = unidirectional ? TMU_ADP_CS_3_UDM : 0; + return tb_port_tmu_write(port, TMU_ADP_CS_3, TMU_ADP_CS_3_UDM, val); +} + +static inline int tb_port_tmu_unidirectional_disable(struct tb_port *port) +{ + return tb_port_tmu_set_unidirectional(port, false); +} + +static bool tb_port_tmu_is_unidirectional(struct tb_port *port) +{ + int ret; + u32 val; + + ret = tb_port_read(port, &val, TB_CFG_PORT, + port->cap_tmu + TMU_ADP_CS_3, 1); + if (ret) + return false; + + return val & TMU_ADP_CS_3_UDM; +} + +static int tb_switch_tmu_set_time_disruption(struct tb_switch *sw, bool set) +{ + int ret; + u32 val; + + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, + sw->tmu.cap + TMU_RTR_CS_0, 1); + if (ret) + return ret; + + if (set) + val |= TMU_RTR_CS_0_TD; + else + val &= ~TMU_RTR_CS_0_TD; + + return tb_sw_write(sw, &val, TB_CFG_SWITCH, + sw->tmu.cap + TMU_RTR_CS_0, 1); +} + +/** + * tb_switch_tmu_init() - Initialize switch TMU structures + * @sw: Switch to initialized + * + * This function must be called before other TMU related functions to + * makes the internal structures are filled in correctly. Does not + * change any hardware configuration. + */ +int tb_switch_tmu_init(struct tb_switch *sw) +{ + int ret, i; + + if (tb_switch_is_icm(sw)) + return 0; + + ret = tb_switch_find_cap(sw, TB_SWITCH_CAP_TMU); + if (ret > 0) + sw->tmu.cap = ret; + + tb_switch_for_each_port(sw, i) { + struct tb_port *port = &sw->ports[i]; + int cap; + + cap = tb_port_find_cap(port, TB_PORT_CAP_TIME1); + if (cap > 0) + port->cap_tmu = cap; + } + + ret = tb_switch_tmu_rate_read(sw); + if (ret < 0) + return ret; + + sw->tmu.rate = ret; + + sw->tmu.has_ucap = tb_switch_tmu_ucap_supported(sw); + if (sw->tmu.has_ucap) { + tb_sw_dbg(sw, "TMU: supports uni-directional mode\n"); + + if (tb_route(sw)) { + struct tb_port *up = tb_upstream_port(sw); + + sw->tmu.unidirectional = + tb_port_tmu_is_unidirectional(up); + } + } else { + sw->tmu.unidirectional = false; + } + + tb_sw_dbg(sw, "TMU: current mode: %s\n", tb_switch_tmu_mode_name(sw)); + return 0; +} + +/** + * tb_switch_tmu_post_time() - Update switch local time + * @sw: Switch whose time to update + * + * Updates switch local time using time posting procedure. + */ +int tb_switch_tmu_post_time(struct tb_switch *sw) +{ + unsigned int post_local_time_offset, post_time_offset; + struct tb_switch *root_switch = sw->tb->root_switch; + u64 hi, mid, lo, local_time, post_time; + int i, ret, retries = 100; + u32 gm_local_time[3]; + + if (!tb_route(sw)) + return 0; + + if (!tb_switch_is_usb4(sw)) + return 0; + + /* Need to be able to read the grand master time */ + if (!root_switch->tmu.cap) + return 0; + + ret = tb_sw_read(root_switch, gm_local_time, TB_CFG_SWITCH, + root_switch->tmu.cap + TMU_RTR_CS_1, + ARRAY_SIZE(gm_local_time)); + if (ret) + return ret; + + for (i = 0; i < ARRAY_SIZE(gm_local_time); i++) + tb_sw_dbg(root_switch, "local_time[%d]=0x%08x\n", i, + gm_local_time[i]); + + /* Convert to nanoseconds (drop fractional part) */ + hi = gm_local_time[2] & TMU_RTR_CS_3_LOCAL_TIME_NS_MASK; + mid = gm_local_time[1]; + lo = (gm_local_time[0] & TMU_RTR_CS_1_LOCAL_TIME_NS_MASK) >> + TMU_RTR_CS_1_LOCAL_TIME_NS_SHIFT; + local_time = hi << 48 | mid << 16 | lo; + + /* Tell the switch that time sync is disrupted for a while */ + ret = tb_switch_tmu_set_time_disruption(sw, true); + if (ret) + return ret; + + post_local_time_offset = sw->tmu.cap + TMU_RTR_CS_22; + post_time_offset = sw->tmu.cap + TMU_RTR_CS_24; + + /* + * Write the Grandmaster time to the Post Local Time registers + * of the new switch. + */ + ret = tb_sw_write(sw, &local_time, TB_CFG_SWITCH, + post_local_time_offset, 2); + if (ret) + goto out; + + /* + * Have the new switch update its local time (by writing 1 to + * the post_time registers) and wait for the completion of the + * same (post_time register becomes 0). This means the time has + * been converged properly. + */ + post_time = 1; + + ret = tb_sw_write(sw, &post_time, TB_CFG_SWITCH, post_time_offset, 2); + if (ret) + goto out; + + do { + usleep_range(5, 10); + ret = tb_sw_read(sw, &post_time, TB_CFG_SWITCH, + post_time_offset, 2); + if (ret) + goto out; + } while (--retries && post_time); + + if (!retries) { + ret = -ETIMEDOUT; + goto out; + } + + tb_sw_dbg(sw, "TMU: updated local time to %#llx\n", local_time); + +out: + tb_switch_tmu_set_time_disruption(sw, false); + return ret; +} + +/** + * tb_switch_tmu_disable() - Disable TMU of a switch + * @sw: Switch whose TMU to disable + * + * Turns off TMU of @sw if it is enabled. If not enabled does nothing. + */ +int tb_switch_tmu_disable(struct tb_switch *sw) +{ + int ret; + + if (!tb_switch_is_usb4(sw)) + return 0; + + /* Already disabled? */ + if (sw->tmu.rate == TB_SWITCH_TMU_RATE_OFF) + return 0; + + if (sw->tmu.unidirectional) { + struct tb_switch *parent = tb_switch_parent(sw); + struct tb_port *up, *down; + + up = tb_upstream_port(sw); + down = tb_port_at(tb_route(sw), parent); + + /* The switch may be unplugged so ignore any errors */ + tb_port_tmu_unidirectional_disable(up); + ret = tb_port_tmu_unidirectional_disable(down); + if (ret) + return ret; + } + + tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_OFF); + + sw->tmu.unidirectional = false; + sw->tmu.rate = TB_SWITCH_TMU_RATE_OFF; + + tb_sw_dbg(sw, "TMU: disabled\n"); + return 0; +} + +/** + * tb_switch_tmu_enable() - Enable TMU on a switch + * @sw: Switch whose TMU to enable + * + * Enables TMU of a switch to be in bi-directional, HiFi mode. In this mode + * all tunneling should work. + */ +int tb_switch_tmu_enable(struct tb_switch *sw) +{ + int ret; + + if (!tb_switch_is_usb4(sw)) + return 0; + + ret = tb_switch_tmu_set_time_disruption(sw, true); + if (ret) + return ret; + + /* Change mode to bi-directional */ + if (tb_route(sw) && sw->tmu.unidirectional) { + struct tb_switch *parent = tb_switch_parent(sw); + struct tb_port *up, *down; + + up = tb_upstream_port(sw); + down = tb_port_at(tb_route(sw), parent); + + ret = tb_port_tmu_unidirectional_disable(down); + if (ret) + return ret; + + ret = tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_HIFI); + if (ret) + return ret; + + ret = tb_port_tmu_unidirectional_disable(up); + if (ret) + return ret; + } else { + ret = tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_HIFI); + if (ret) + return ret; + } + + sw->tmu.unidirectional = false; + sw->tmu.rate = TB_SWITCH_TMU_RATE_HIFI; + tb_sw_dbg(sw, "TMU: mode set to: %s\n", tb_switch_tmu_mode_name(sw)); + + return tb_switch_tmu_set_time_disruption(sw, false); +}