swh:1:snp:49cd9498d6cccc5e78252c27dcb645bcf7bf0c91
Tip revision: b2d229d4ddb17db541098b83524d901257e93845 authored by Linus Torvalds on 17 April 2022, 20:57:31 UTC
Linux 5.18-rc3
Linux 5.18-rc3
Tip revision: b2d229d
tmu.c
// 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 inline int tb_port_tmu_unidirectional_enable(struct tb_port *port)
{
return tb_port_tmu_set_unidirectional(port, true);
}
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_port_tmu_time_sync(struct tb_port *port, bool time_sync)
{
u32 val = time_sync ? TMU_ADP_CS_6_DTS : 0;
return tb_port_tmu_write(port, TMU_ADP_CS_6, TMU_ADP_CS_6_DTS, val);
}
static int tb_port_tmu_time_sync_disable(struct tb_port *port)
{
return tb_port_tmu_time_sync(port, true);
}
static int tb_port_tmu_time_sync_enable(struct tb_port *port)
{
return tb_port_tmu_time_sync(port, false);
}
static int tb_switch_tmu_set_time_disruption(struct tb_switch *sw, bool set)
{
u32 val, offset, bit;
int ret;
if (tb_switch_is_usb4(sw)) {
offset = sw->tmu.cap + TMU_RTR_CS_0;
bit = TMU_RTR_CS_0_TD;
} else {
offset = sw->cap_vsec_tmu + TB_TIME_VSEC_3_CS_26;
bit = TB_TIME_VSEC_3_CS_26_TD;
}
ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, offset, 1);
if (ret)
return ret;
if (set)
val |= bit;
else
val &= ~bit;
return tb_sw_write(sw, &val, TB_CFG_SWITCH, offset, 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)
{
struct tb_port *port;
int ret;
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, port) {
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_time_high_offset, post_time_high = 0;
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;
post_time_high_offset = sw->tmu.cap + TMU_RTR_CS_25;
/*
* 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:
* 1) writing 0x1 to the Post Time Low register and 0xffffffff to
* Post Time High register.
* 2) write 0 to Post Time High register and then wait for
* the completion of the post_time register becomes 0.
* This means the time has been converged properly.
*/
post_time = 0xffffffff00000001ULL;
ret = tb_sw_write(sw, &post_time, TB_CFG_SWITCH, post_time_offset, 2);
if (ret)
goto out;
ret = tb_sw_write(sw, &post_time_high, TB_CFG_SWITCH,
post_time_high_offset, 1);
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)
{
/*
* No need to disable TMU on devices that don't support CLx since
* on these devices e.g. Alpine Ridge and earlier, the TMU mode
* HiFi bi-directional is enabled by default and we don't change it.
*/
if (!tb_switch_is_clx_supported(sw))
return 0;
/* Already disabled? */
if (sw->tmu.rate == TB_SWITCH_TMU_RATE_OFF)
return 0;
if (tb_route(sw)) {
bool unidirectional = tb_switch_tmu_hifi_is_enabled(sw, true);
struct tb_switch *parent = tb_switch_parent(sw);
struct tb_port *down, *up;
int ret;
down = tb_port_at(tb_route(sw), parent);
up = tb_upstream_port(sw);
/*
* In case of uni-directional time sync, TMU handshake is
* initiated by upstream router. In case of bi-directional
* time sync, TMU handshake is initiated by downstream router.
* Therefore, we change the rate to off in the respective
* router.
*/
if (unidirectional)
tb_switch_tmu_rate_write(parent, TB_SWITCH_TMU_RATE_OFF);
else
tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_OFF);
tb_port_tmu_time_sync_disable(up);
ret = tb_port_tmu_time_sync_disable(down);
if (ret)
return ret;
if (unidirectional) {
/* 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;
}
} else {
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;
}
static void __tb_switch_tmu_off(struct tb_switch *sw, bool unidirectional)
{
struct tb_switch *parent = tb_switch_parent(sw);
struct tb_port *down, *up;
down = tb_port_at(tb_route(sw), parent);
up = tb_upstream_port(sw);
/*
* In case of any failure in one of the steps when setting
* bi-directional or uni-directional TMU mode, get back to the TMU
* configurations in off mode. In case of additional failures in
* the functions below, ignore them since the caller shall already
* report a failure.
*/
tb_port_tmu_time_sync_disable(down);
tb_port_tmu_time_sync_disable(up);
if (unidirectional)
tb_switch_tmu_rate_write(parent, TB_SWITCH_TMU_RATE_OFF);
else
tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_OFF);
tb_port_tmu_unidirectional_disable(down);
tb_port_tmu_unidirectional_disable(up);
}
/*
* This function is called when the previous TMU mode was
* TB_SWITCH_TMU_RATE_OFF.
*/
static int __tb_switch_tmu_enable_bidirectional(struct tb_switch *sw)
{
struct tb_switch *parent = tb_switch_parent(sw);
struct tb_port *up, *down;
int ret;
up = tb_upstream_port(sw);
down = tb_port_at(tb_route(sw), parent);
ret = tb_port_tmu_unidirectional_disable(up);
if (ret)
return ret;
ret = tb_port_tmu_unidirectional_disable(down);
if (ret)
goto out;
ret = tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_HIFI);
if (ret)
goto out;
ret = tb_port_tmu_time_sync_enable(up);
if (ret)
goto out;
ret = tb_port_tmu_time_sync_enable(down);
if (ret)
goto out;
return 0;
out:
__tb_switch_tmu_off(sw, false);
return ret;
}
static int tb_switch_tmu_objection_mask(struct tb_switch *sw)
{
u32 val;
int ret;
ret = tb_sw_read(sw, &val, TB_CFG_SWITCH,
sw->cap_vsec_tmu + TB_TIME_VSEC_3_CS_9, 1);
if (ret)
return ret;
val &= ~TB_TIME_VSEC_3_CS_9_TMU_OBJ_MASK;
return tb_sw_write(sw, &val, TB_CFG_SWITCH,
sw->cap_vsec_tmu + TB_TIME_VSEC_3_CS_9, 1);
}
static int tb_switch_tmu_unidirectional_enable(struct tb_switch *sw)
{
struct tb_port *up = tb_upstream_port(sw);
return tb_port_tmu_write(up, TMU_ADP_CS_6,
TMU_ADP_CS_6_DISABLE_TMU_OBJ_MASK,
TMU_ADP_CS_6_DISABLE_TMU_OBJ_MASK);
}
/*
* This function is called when the previous TMU mode was
* TB_SWITCH_TMU_RATE_OFF.
*/
static int __tb_switch_tmu_enable_unidirectional(struct tb_switch *sw)
{
struct tb_switch *parent = tb_switch_parent(sw);
struct tb_port *up, *down;
int ret;
up = tb_upstream_port(sw);
down = tb_port_at(tb_route(sw), parent);
ret = tb_switch_tmu_rate_write(parent, TB_SWITCH_TMU_RATE_HIFI);
if (ret)
return ret;
ret = tb_port_tmu_unidirectional_enable(up);
if (ret)
goto out;
ret = tb_port_tmu_time_sync_enable(up);
if (ret)
goto out;
ret = tb_port_tmu_unidirectional_enable(down);
if (ret)
goto out;
ret = tb_port_tmu_time_sync_enable(down);
if (ret)
goto out;
return 0;
out:
__tb_switch_tmu_off(sw, true);
return ret;
}
static int tb_switch_tmu_hifi_enable(struct tb_switch *sw)
{
bool unidirectional = sw->tmu.unidirectional_request;
int ret;
if (unidirectional && !sw->tmu.has_ucap)
return -EOPNOTSUPP;
/*
* No need to enable TMU on devices that don't support CLx since on
* these devices e.g. Alpine Ridge and earlier, the TMU mode HiFi
* bi-directional is enabled by default.
*/
if (!tb_switch_is_clx_supported(sw))
return 0;
if (tb_switch_tmu_hifi_is_enabled(sw, sw->tmu.unidirectional_request))
return 0;
if (tb_switch_is_titan_ridge(sw) && unidirectional) {
/* Titan Ridge supports only CL0s */
if (!tb_switch_is_cl0s_enabled(sw))
return -EOPNOTSUPP;
ret = tb_switch_tmu_objection_mask(sw);
if (ret)
return ret;
ret = tb_switch_tmu_unidirectional_enable(sw);
if (ret)
return ret;
}
ret = tb_switch_tmu_set_time_disruption(sw, true);
if (ret)
return ret;
if (tb_route(sw)) {
/* The used mode changes are from OFF to HiFi-Uni/HiFi-BiDir */
if (sw->tmu.rate == TB_SWITCH_TMU_RATE_OFF) {
if (unidirectional)
ret = __tb_switch_tmu_enable_unidirectional(sw);
else
ret = __tb_switch_tmu_enable_bidirectional(sw);
if (ret)
return ret;
}
sw->tmu.unidirectional = unidirectional;
} else {
/*
* Host router port configurations are written as
* part of configurations for downstream port of the parent
* of the child node - see above.
* Here only the host router' rate configuration is written.
*/
ret = tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_HIFI);
if (ret)
return ret;
}
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);
}
/**
* tb_switch_tmu_enable() - Enable TMU on a router
* @sw: Router whose TMU to enable
*
* Enables TMU of a router to be in uni-directional or bi-directional HiFi mode.
* Calling tb_switch_tmu_configure() is required before calling this function,
* to select the mode HiFi and directionality (uni-directional/bi-directional).
* In both modes all tunneling should work. Uni-directional mode is required for
* CLx (Link Low-Power) to work.
*/
int tb_switch_tmu_enable(struct tb_switch *sw)
{
if (sw->tmu.rate_request == TB_SWITCH_TMU_RATE_NORMAL)
return -EOPNOTSUPP;
return tb_switch_tmu_hifi_enable(sw);
}
/**
* tb_switch_tmu_configure() - Configure the TMU rate and directionality
* @sw: Router whose mode to change
* @rate: Rate to configure Off/LowRes/HiFi
* @unidirectional: If uni-directional (bi-directional otherwise)
*
* Selects the rate of the TMU and directionality (uni-directional or
* bi-directional). Must be called before tb_switch_tmu_enable().
*/
void tb_switch_tmu_configure(struct tb_switch *sw,
enum tb_switch_tmu_rate rate, bool unidirectional)
{
sw->tmu.unidirectional_request = unidirectional;
sw->tmu.rate_request = rate;
}