From d0f1e0c2a6990922818d6616a48d3d92bb7ddac1 Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Tue, 22 Feb 2022 19:31:47 +0200 Subject: thunderbolt: Add support for receiver lane margining USB4 spec defines standard set of registers to be used for receiver lane margining. This is useful for I/O interface quality and electrical robustness validation during manufacturing. Expose receiver lane margining through new debugfs directory "margining" that is added under each connected USB4 port. Users can then run the margining by writing to the exposed attributes under that directory. Signed-off-by: Mika Westerberg --- drivers/thunderbolt/usb4.c | 120 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) (limited to 'drivers/thunderbolt/usb4.c') diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c index 3a2e7126db9d..70036f3e37a5 100644 --- a/drivers/thunderbolt/usb4.c +++ b/drivers/thunderbolt/usb4.c @@ -1384,6 +1384,126 @@ bool usb4_port_clx_supported(struct tb_port *port) return !!(val & PORT_CS_18_CPS); } +/** + * usb4_port_margining_caps() - Read USB4 port marginig capabilities + * @port: USB4 port + * @caps: Array with at least two elements to hold the results + * + * Reads the USB4 port lane margining capabilities into @caps. + */ +int usb4_port_margining_caps(struct tb_port *port, u32 *caps) +{ + int ret; + + ret = usb4_port_sb_op(port, USB4_SB_TARGET_ROUTER, 0, + USB4_SB_OPCODE_READ_LANE_MARGINING_CAP, 500); + if (ret) + return ret; + + return usb4_port_sb_read(port, USB4_SB_TARGET_ROUTER, 0, + USB4_SB_DATA, caps, sizeof(*caps) * 2); +} + +/** + * usb4_port_hw_margin() - Run hardware lane margining on port + * @port: USB4 port + * @lanes: Which lanes to run (must match the port capabilities). Can be + * %0, %1 or %7. + * @ber_level: BER level contour value + * @timing: Perform timing margining instead of voltage + * @right_high: Use Right/high margin instead of left/low + * @results: Array with at least two elements to hold the results + * + * Runs hardware lane margining on USB4 port and returns the result in + * @results. + */ +int usb4_port_hw_margin(struct tb_port *port, unsigned int lanes, + unsigned int ber_level, bool timing, bool right_high, + u32 *results) +{ + u32 val; + int ret; + + val = lanes; + if (timing) + val |= USB4_MARGIN_HW_TIME; + if (right_high) + val |= USB4_MARGIN_HW_RH; + if (ber_level) + val |= (ber_level << USB4_MARGIN_HW_BER_SHIFT) & + USB4_MARGIN_HW_BER_MASK; + + ret = usb4_port_sb_write(port, USB4_SB_TARGET_ROUTER, 0, + USB4_SB_METADATA, &val, sizeof(val)); + if (ret) + return ret; + + ret = usb4_port_sb_op(port, USB4_SB_TARGET_ROUTER, 0, + USB4_SB_OPCODE_RUN_HW_LANE_MARGINING, 2500); + if (ret) + return ret; + + return usb4_port_sb_read(port, USB4_SB_TARGET_ROUTER, 0, + USB4_SB_DATA, results, sizeof(*results) * 2); +} + +/** + * usb4_port_sw_margin() - Run software lane margining on port + * @port: USB4 port + * @lanes: Which lanes to run (must match the port capabilities). Can be + * %0, %1 or %7. + * @timing: Perform timing margining instead of voltage + * @right_high: Use Right/high margin instead of left/low + * @counter: What to do with the error counter + * + * Runs software lane margining on USB4 port. Read back the error + * counters by calling usb4_port_sw_margin_errors(). Returns %0 in + * success and negative errno otherwise. + */ +int usb4_port_sw_margin(struct tb_port *port, unsigned int lanes, bool timing, + bool right_high, u32 counter) +{ + u32 val; + int ret; + + val = lanes; + if (timing) + val |= USB4_MARGIN_SW_TIME; + if (right_high) + val |= USB4_MARGIN_SW_RH; + val |= (counter << USB4_MARGIN_SW_COUNTER_SHIFT) & + USB4_MARGIN_SW_COUNTER_MASK; + + ret = usb4_port_sb_write(port, USB4_SB_TARGET_ROUTER, 0, + USB4_SB_METADATA, &val, sizeof(val)); + if (ret) + return ret; + + return usb4_port_sb_op(port, USB4_SB_TARGET_ROUTER, 0, + USB4_SB_OPCODE_RUN_SW_LANE_MARGINING, 2500); +} + +/** + * usb4_port_sw_margin_errors() - Read the software margining error counters + * @port: USB4 port + * @errors: Error metadata is copied here. + * + * This reads back the software margining error counters from the port. + * Returns %0 in success and negative errno otherwise. + */ +int usb4_port_sw_margin_errors(struct tb_port *port, u32 *errors) +{ + int ret; + + ret = usb4_port_sb_op(port, USB4_SB_TARGET_ROUTER, 0, + USB4_SB_OPCODE_READ_SW_MARGIN_ERR, 150); + if (ret) + return ret; + + return usb4_port_sb_read(port, USB4_SB_TARGET_ROUTER, 0, + USB4_SB_METADATA, errors, sizeof(*errors)); +} + static inline int usb4_port_retimer_op(struct tb_port *port, u8 index, enum usb4_sb_opcode opcode, int timeout_msec) -- cgit From 5d2569cb4a65c373896ec0217febdf88739ed295 Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Mon, 26 Sep 2022 09:33:50 -0500 Subject: thunderbolt: Explicitly enable lane adapter hotplug events at startup Software that has run before the USB4 CM in Linux runs may have disabled hotplug events for a given lane adapter. Other CMs such as that one distributed with Windows 11 will enable hotplug events. Do the same thing in the Linux CM which fixes hotplug events on "AMD Pink Sardine". Cc: stable@vger.kernel.org Signed-off-by: Mario Limonciello Signed-off-by: Mika Westerberg --- drivers/thunderbolt/usb4.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'drivers/thunderbolt/usb4.c') diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c index 70036f3e37a5..38c10c30e6cf 100644 --- a/drivers/thunderbolt/usb4.c +++ b/drivers/thunderbolt/usb4.c @@ -1046,6 +1046,26 @@ int usb4_port_unlock(struct tb_port *port) return tb_port_write(port, &val, TB_CFG_PORT, ADP_CS_4, 1); } +/** + * usb4_port_hotplug_enable() - Enables hotplug for a port + * @port: USB4 port to operate on + * + * Enables hot plug events on a given port. This is only intended + * to be used on lane, DP-IN, and DP-OUT adapters. + */ +int usb4_port_hotplug_enable(struct tb_port *port) +{ + int ret; + u32 val; + + ret = tb_port_read(port, &val, TB_CFG_PORT, ADP_CS_5, 1); + if (ret) + return ret; + + val &= ~ADP_CS_5_DHP; + return tb_port_write(port, &val, TB_CFG_PORT, ADP_CS_5, 1); +} + static int usb4_port_set_configured(struct tb_port *port, bool configured) { int ret; -- cgit