From 01da6b99d49f60b1edead44e33569b1a2e9f49b7 Mon Sep 17 00:00:00 2001 From: Sanath S Date: Sat, 13 Jan 2024 11:39:57 +0200 Subject: [PATCH] thunderbolt: Introduce tb_port_reset() Introduce a function that issues Downstream Port Reset to a USB4 port. This supports Thunderbolt 2, 3 and USB4 routers. Signed-off-by: Sanath S Signed-off-by: Mika Westerberg --- drivers/thunderbolt/lc.c | 45 +++++++++++++++++++++++++++++++++++ drivers/thunderbolt/switch.c | 7 ++++++ drivers/thunderbolt/tb.h | 2 ++ drivers/thunderbolt/tb_regs.h | 4 ++++ drivers/thunderbolt/usb4.c | 39 ++++++++++++++++++++++++++++++ 5 files changed, 97 insertions(+) diff --git a/drivers/thunderbolt/lc.c b/drivers/thunderbolt/lc.c index 633970fbe9b0..63cb4b6afb71 100644 --- a/drivers/thunderbolt/lc.c +++ b/drivers/thunderbolt/lc.c @@ -6,6 +6,8 @@ * Author: Mika Westerberg */ +#include + #include "tb.h" /** @@ -45,6 +47,49 @@ static int find_port_lc_cap(struct tb_port *port) return sw->cap_lc + start + phys * size; } +/** + * tb_lc_reset_port() - Trigger downstream port reset through LC + * @port: Port that is reset + * + * Triggers downstream port reset through link controller registers. + * Returns %0 in case of success negative errno otherwise. Only supports + * non-USB4 routers with link controller (that's Thunderbolt 2 and + * Thunderbolt 3). + */ +int tb_lc_reset_port(struct tb_port *port) +{ + struct tb_switch *sw = port->sw; + int cap, ret; + u32 mode; + + if (sw->generation < 2) + return -EINVAL; + + cap = find_port_lc_cap(port); + if (cap < 0) + return cap; + + ret = tb_sw_read(sw, &mode, TB_CFG_SWITCH, cap + TB_LC_PORT_MODE, 1); + if (ret) + return ret; + + mode |= TB_LC_PORT_MODE_DPR; + + ret = tb_sw_write(sw, &mode, TB_CFG_SWITCH, cap + TB_LC_PORT_MODE, 1); + if (ret) + return ret; + + fsleep(10000); + + ret = tb_sw_read(sw, &mode, TB_CFG_SWITCH, cap + TB_LC_PORT_MODE, 1); + if (ret) + return ret; + + mode &= ~TB_LC_PORT_MODE_DPR; + + return tb_sw_write(sw, &mode, TB_CFG_SWITCH, cap + TB_LC_PORT_MODE, 1); +} + static int tb_lc_set_port_configured(struct tb_port *port, bool configured) { bool upstream = tb_is_upstream_port(port); diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index 900114ba4371..b0e69d4313ce 100644 --- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -676,6 +676,13 @@ int tb_port_disable(struct tb_port *port) return __tb_port_enable(port, false); } +static int tb_port_reset(struct tb_port *port) +{ + if (tb_switch_is_usb4(port->sw)) + return port->cap_usb4 ? usb4_port_reset(port) : 0; + return tb_lc_reset_port(port); +} + /* * tb_init_port() - initialize a port * diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h index 997c5a536905..c38b047ba14b 100644 --- a/drivers/thunderbolt/tb.h +++ b/drivers/thunderbolt/tb.h @@ -1169,6 +1169,7 @@ int tb_drom_read(struct tb_switch *sw); int tb_drom_read_uid_only(struct tb_switch *sw, u64 *uid); int tb_lc_read_uuid(struct tb_switch *sw, u32 *uuid); +int tb_lc_reset_port(struct tb_port *port); int tb_lc_configure_port(struct tb_port *port); void tb_lc_unconfigure_port(struct tb_port *port); int tb_lc_configure_xdomain(struct tb_port *port); @@ -1301,6 +1302,7 @@ void usb4_switch_remove_ports(struct tb_switch *sw); int usb4_port_unlock(struct tb_port *port); int usb4_port_hotplug_enable(struct tb_port *port); +int usb4_port_reset(struct tb_port *port); int usb4_port_configure(struct tb_port *port); void usb4_port_unconfigure(struct tb_port *port); int usb4_port_configure_xdomain(struct tb_port *port, struct tb_xdomain *xd); diff --git a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h index 87e4795275fe..efcae298b370 100644 --- a/drivers/thunderbolt/tb_regs.h +++ b/drivers/thunderbolt/tb_regs.h @@ -389,6 +389,7 @@ struct tb_regs_port_header { #define PORT_CS_18_CSA BIT(22) #define PORT_CS_18_TIP BIT(24) #define PORT_CS_19 0x13 +#define PORT_CS_19_DPR BIT(0) #define PORT_CS_19_PC BIT(3) #define PORT_CS_19_PID BIT(4) #define PORT_CS_19_WOC BIT(16) @@ -584,6 +585,9 @@ struct tb_regs_hop { #define TB_LC_POWER 0x740 /* Link controller registers */ +#define TB_LC_PORT_MODE 0x26 +#define TB_LC_PORT_MODE_DPR BIT(0) + #define TB_LC_CS_42 0x2a #define TB_LC_CS_42_USB_PLUGGED BIT(31) diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c index f8f0d24ff6e4..4b35898aa216 100644 --- a/drivers/thunderbolt/usb4.c +++ b/drivers/thunderbolt/usb4.c @@ -1113,6 +1113,45 @@ int usb4_port_hotplug_enable(struct tb_port *port) return tb_port_write(port, &val, TB_CFG_PORT, ADP_CS_5, 1); } +/** + * usb4_port_reset() - Issue downstream port reset + * @port: USB4 port to reset + * + * Issues downstream port reset to @port. + */ +int usb4_port_reset(struct tb_port *port) +{ + int ret; + u32 val; + + if (!port->cap_usb4) + return -EINVAL; + + ret = tb_port_read(port, &val, TB_CFG_PORT, + port->cap_usb4 + PORT_CS_19, 1); + if (ret) + return ret; + + val |= PORT_CS_19_DPR; + + ret = tb_port_write(port, &val, TB_CFG_PORT, + port->cap_usb4 + PORT_CS_19, 1); + if (ret) + return ret; + + fsleep(10000); + + ret = tb_port_read(port, &val, TB_CFG_PORT, + port->cap_usb4 + PORT_CS_19, 1); + if (ret) + return ret; + + val &= ~PORT_CS_19_DPR; + + return tb_port_write(port, &val, TB_CFG_PORT, + port->cap_usb4 + PORT_CS_19, 1); +} + static int usb4_port_set_configured(struct tb_port *port, bool configured) { int ret;