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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
commit034dd340b08be1f2f0477ad16131d609f9dbd53c (patch)
tree2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/thunderbolt/clx.c
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure
Diffstat (limited to 'drivers/thunderbolt/clx.c')
-rw-r--r--drivers/thunderbolt/clx.c428
1 files changed, 428 insertions, 0 deletions
diff --git a/drivers/thunderbolt/clx.c b/drivers/thunderbolt/clx.c
new file mode 100644
index 000000000..1637e79d9
--- /dev/null
+++ b/drivers/thunderbolt/clx.c
@@ -0,0 +1,428 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CLx support
+ *
+ * Copyright (C) 2020 - 2023, Intel Corporation
+ * Authors: Gil Fine <gil.fine@intel.com>
+ * Mika Westerberg <mika.westerberg@linux.intel.com>
+ */
+
+#include <linux/module.h>
+
+#include "tb.h"
+
+static bool clx_enabled = true;
+module_param_named(clx, clx_enabled, bool, 0444);
+MODULE_PARM_DESC(clx, "allow low power states on the high-speed lanes (default: true)");
+
+static const char *clx_name(unsigned int clx)
+{
+ switch (clx) {
+ case TB_CL0S | TB_CL1 | TB_CL2:
+ return "CL0s/CL1/CL2";
+ case TB_CL1 | TB_CL2:
+ return "CL1/CL2";
+ case TB_CL0S | TB_CL2:
+ return "CL0s/CL2";
+ case TB_CL0S | TB_CL1:
+ return "CL0s/CL1";
+ case TB_CL0S:
+ return "CL0s";
+ case 0:
+ return "disabled";
+ default:
+ return "unknown";
+ }
+}
+
+static int tb_port_pm_secondary_set(struct tb_port *port, bool secondary)
+{
+ u32 phy;
+ int ret;
+
+ ret = tb_port_read(port, &phy, TB_CFG_PORT,
+ port->cap_phy + LANE_ADP_CS_1, 1);
+ if (ret)
+ return ret;
+
+ if (secondary)
+ phy |= LANE_ADP_CS_1_PMS;
+ else
+ phy &= ~LANE_ADP_CS_1_PMS;
+
+ return tb_port_write(port, &phy, TB_CFG_PORT,
+ port->cap_phy + LANE_ADP_CS_1, 1);
+}
+
+static int tb_port_pm_secondary_enable(struct tb_port *port)
+{
+ return tb_port_pm_secondary_set(port, true);
+}
+
+static int tb_port_pm_secondary_disable(struct tb_port *port)
+{
+ return tb_port_pm_secondary_set(port, false);
+}
+
+/* Called for USB4 or Titan Ridge routers only */
+static bool tb_port_clx_supported(struct tb_port *port, unsigned int clx)
+{
+ u32 val, mask = 0;
+ bool ret;
+
+ /* Don't enable CLx in case of two single-lane links */
+ if (!port->bonded && port->dual_link_port)
+ return false;
+
+ /* Don't enable CLx in case of inter-domain link */
+ if (port->xdomain)
+ return false;
+
+ if (tb_switch_is_usb4(port->sw)) {
+ if (!usb4_port_clx_supported(port))
+ return false;
+ } else if (!tb_lc_is_clx_supported(port)) {
+ return false;
+ }
+
+ if (clx & TB_CL0S)
+ mask |= LANE_ADP_CS_0_CL0S_SUPPORT;
+ if (clx & TB_CL1)
+ mask |= LANE_ADP_CS_0_CL1_SUPPORT;
+ if (clx & TB_CL2)
+ mask |= LANE_ADP_CS_0_CL2_SUPPORT;
+
+ ret = tb_port_read(port, &val, TB_CFG_PORT,
+ port->cap_phy + LANE_ADP_CS_0, 1);
+ if (ret)
+ return false;
+
+ return !!(val & mask);
+}
+
+static int tb_port_clx_set(struct tb_port *port, unsigned int clx, bool enable)
+{
+ u32 phy, mask = 0;
+ int ret;
+
+ if (clx & TB_CL0S)
+ mask |= LANE_ADP_CS_1_CL0S_ENABLE;
+ if (clx & TB_CL1)
+ mask |= LANE_ADP_CS_1_CL1_ENABLE;
+ if (clx & TB_CL2)
+ mask |= LANE_ADP_CS_1_CL2_ENABLE;
+
+ if (!mask)
+ return -EOPNOTSUPP;
+
+ ret = tb_port_read(port, &phy, TB_CFG_PORT,
+ port->cap_phy + LANE_ADP_CS_1, 1);
+ if (ret)
+ return ret;
+
+ if (enable)
+ phy |= mask;
+ else
+ phy &= ~mask;
+
+ return tb_port_write(port, &phy, TB_CFG_PORT,
+ port->cap_phy + LANE_ADP_CS_1, 1);
+}
+
+static int tb_port_clx_disable(struct tb_port *port, unsigned int clx)
+{
+ return tb_port_clx_set(port, clx, false);
+}
+
+static int tb_port_clx_enable(struct tb_port *port, unsigned int clx)
+{
+ return tb_port_clx_set(port, clx, true);
+}
+
+static int tb_port_clx(struct tb_port *port)
+{
+ u32 val;
+ int ret;
+
+ if (!tb_port_clx_supported(port, TB_CL0S | TB_CL1 | TB_CL2))
+ return 0;
+
+ ret = tb_port_read(port, &val, TB_CFG_PORT,
+ port->cap_phy + LANE_ADP_CS_1, 1);
+ if (ret)
+ return ret;
+
+ if (val & LANE_ADP_CS_1_CL0S_ENABLE)
+ ret |= TB_CL0S;
+ if (val & LANE_ADP_CS_1_CL1_ENABLE)
+ ret |= TB_CL1;
+ if (val & LANE_ADP_CS_1_CL2_ENABLE)
+ ret |= TB_CL2;
+
+ return ret;
+}
+
+/**
+ * tb_port_clx_is_enabled() - Is given CL state enabled
+ * @port: USB4 port to check
+ * @clx: Mask of CL states to check
+ *
+ * Return: %true if any of the given CL states is enabled for @port,
+ * %false otherwise.
+ */
+bool tb_port_clx_is_enabled(struct tb_port *port, unsigned int clx)
+{
+ return !!(tb_port_clx(port) & clx);
+}
+
+/**
+ * tb_switch_clx_is_supported() - Is CLx supported on this type of router
+ * @sw: The router to check CLx support for
+ *
+ * Return: %true if CLx is supported, %false otherwise.
+ */
+static bool tb_switch_clx_is_supported(const struct tb_switch *sw)
+{
+ if (!clx_enabled)
+ return false;
+
+ if (sw->quirks & QUIRK_NO_CLX)
+ return false;
+
+ /*
+ * CLx is not enabled and validated on Intel USB4 platforms
+ * before Alder Lake.
+ */
+ if (tb_switch_is_tiger_lake(sw))
+ return false;
+
+ return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw);
+}
+
+/**
+ * tb_switch_clx_init() - Initialize router CL states
+ * @sw: Router
+ *
+ * Can be called for any router. Initializes the current CL state by
+ * reading it from the hardware.
+ *
+ * Return: %0 on success, negative errno otherwise.
+ */
+int tb_switch_clx_init(struct tb_switch *sw)
+{
+ struct tb_port *up, *down;
+ unsigned int clx, tmp;
+
+ if (tb_switch_is_icm(sw))
+ return 0;
+
+ if (!tb_route(sw))
+ return 0;
+
+ if (!tb_switch_clx_is_supported(sw))
+ return 0;
+
+ up = tb_upstream_port(sw);
+ down = tb_switch_downstream_port(sw);
+
+ clx = tb_port_clx(up);
+ tmp = tb_port_clx(down);
+ if (clx != tmp)
+ tb_sw_warn(sw, "CLx: inconsistent configuration %#x != %#x\n",
+ clx, tmp);
+
+ tb_sw_dbg(sw, "CLx: current mode: %s\n", clx_name(clx));
+
+ sw->clx = clx;
+ return 0;
+}
+
+static int tb_switch_pm_secondary_resolve(struct tb_switch *sw)
+{
+ struct tb_port *up, *down;
+ int ret;
+
+ if (!tb_route(sw))
+ return 0;
+
+ up = tb_upstream_port(sw);
+ down = tb_switch_downstream_port(sw);
+ ret = tb_port_pm_secondary_enable(up);
+ if (ret)
+ return ret;
+
+ return tb_port_pm_secondary_disable(down);
+}
+
+static int tb_switch_mask_clx_objections(struct tb_switch *sw)
+{
+ int up_port = sw->config.upstream_port_number;
+ u32 offset, val[2], mask_obj, unmask_obj;
+ int ret, i;
+
+ /* Only Titan Ridge of pre-USB4 devices support CLx states */
+ if (!tb_switch_is_titan_ridge(sw))
+ return 0;
+
+ if (!tb_route(sw))
+ return 0;
+
+ /*
+ * In Titan Ridge there are only 2 dual-lane Thunderbolt ports:
+ * Port A consists of lane adapters 1,2 and
+ * Port B consists of lane adapters 3,4
+ * If upstream port is A, (lanes are 1,2), we mask objections from
+ * port B (lanes 3,4) and unmask objections from Port A and vice-versa.
+ */
+ if (up_port == 1) {
+ mask_obj = TB_LOW_PWR_C0_PORT_B_MASK;
+ unmask_obj = TB_LOW_PWR_C1_PORT_A_MASK;
+ offset = TB_LOW_PWR_C1_CL1;
+ } else {
+ mask_obj = TB_LOW_PWR_C1_PORT_A_MASK;
+ unmask_obj = TB_LOW_PWR_C0_PORT_B_MASK;
+ offset = TB_LOW_PWR_C3_CL1;
+ }
+
+ ret = tb_sw_read(sw, &val, TB_CFG_SWITCH,
+ sw->cap_lp + offset, ARRAY_SIZE(val));
+ if (ret)
+ return ret;
+
+ for (i = 0; i < ARRAY_SIZE(val); i++) {
+ val[i] |= mask_obj;
+ val[i] &= ~unmask_obj;
+ }
+
+ return tb_sw_write(sw, &val, TB_CFG_SWITCH,
+ sw->cap_lp + offset, ARRAY_SIZE(val));
+}
+
+static bool validate_mask(unsigned int clx)
+{
+ /* Previous states need to be enabled */
+ if (clx & TB_CL1)
+ return (clx & TB_CL0S) == TB_CL0S;
+ return true;
+}
+
+/**
+ * tb_switch_clx_enable() - Enable CLx on upstream port of specified router
+ * @sw: Router to enable CLx for
+ * @clx: The CLx state to enable
+ *
+ * CLx is enabled only if both sides of the link support CLx, and if both sides
+ * of the link are not configured as two single lane links and only if the link
+ * is not inter-domain link. The complete set of conditions is described in CM
+ * Guide 1.0 section 8.1.
+ *
+ * Return: %0 on success, negative errno otherwise.
+ */
+int tb_switch_clx_enable(struct tb_switch *sw, unsigned int clx)
+{
+ bool up_clx_support, down_clx_support;
+ struct tb_switch *parent_sw;
+ struct tb_port *up, *down;
+ int ret;
+
+ if (!clx || sw->clx == clx)
+ return 0;
+
+ if (!validate_mask(clx))
+ return -EINVAL;
+
+ parent_sw = tb_switch_parent(sw);
+ if (!parent_sw)
+ return 0;
+
+ if (!tb_switch_clx_is_supported(parent_sw) ||
+ !tb_switch_clx_is_supported(sw))
+ return 0;
+
+ /* Only support CL2 for v2 routers */
+ if ((clx & TB_CL2) &&
+ (usb4_switch_version(parent_sw) < 2 ||
+ usb4_switch_version(sw) < 2))
+ return -EOPNOTSUPP;
+
+ ret = tb_switch_pm_secondary_resolve(sw);
+ if (ret)
+ return ret;
+
+ up = tb_upstream_port(sw);
+ down = tb_switch_downstream_port(sw);
+
+ up_clx_support = tb_port_clx_supported(up, clx);
+ down_clx_support = tb_port_clx_supported(down, clx);
+
+ tb_port_dbg(up, "CLx: %s %ssupported\n", clx_name(clx),
+ up_clx_support ? "" : "not ");
+ tb_port_dbg(down, "CLx: %s %ssupported\n", clx_name(clx),
+ down_clx_support ? "" : "not ");
+
+ if (!up_clx_support || !down_clx_support)
+ return -EOPNOTSUPP;
+
+ ret = tb_port_clx_enable(up, clx);
+ if (ret)
+ return ret;
+
+ ret = tb_port_clx_enable(down, clx);
+ if (ret) {
+ tb_port_clx_disable(up, clx);
+ return ret;
+ }
+
+ ret = tb_switch_mask_clx_objections(sw);
+ if (ret) {
+ tb_port_clx_disable(up, clx);
+ tb_port_clx_disable(down, clx);
+ return ret;
+ }
+
+ sw->clx |= clx;
+
+ tb_sw_dbg(sw, "CLx: %s enabled\n", clx_name(clx));
+ return 0;
+}
+
+/**
+ * tb_switch_clx_disable() - Disable CLx on upstream port of specified router
+ * @sw: Router to disable CLx for
+ *
+ * Disables all CL states of the given router. Can be called on any
+ * router and if the states were not enabled already does nothing.
+ *
+ * Return: CL states that were disabled or negative errno otherwise.
+ */
+int tb_switch_clx_disable(struct tb_switch *sw)
+{
+ unsigned int clx = sw->clx;
+ struct tb_port *up, *down;
+ int ret;
+
+ if (!tb_switch_clx_is_supported(sw))
+ return 0;
+
+ if (!clx)
+ return 0;
+
+ if (sw->is_unplugged)
+ return clx;
+
+ up = tb_upstream_port(sw);
+ down = tb_switch_downstream_port(sw);
+
+ ret = tb_port_clx_disable(up, clx);
+ if (ret)
+ return ret;
+
+ ret = tb_port_clx_disable(down, clx);
+ if (ret)
+ return ret;
+
+ sw->clx = 0;
+
+ tb_sw_dbg(sw, "CLx: %s disabled\n", clx_name(clx));
+ return clx;
+}