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authorLinus Torvalds <torvalds@linux-foundation.org>2026-09-13 12:27:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-09-13 12:27:00 -0700
commit22098763a10d9c1340827fcf6edab66f153b27f0 (patch)
tree3962f95a34df034652ff93686cdd156c7197f2d9 /drivers/clocksource/timer-sp804.c
downloadlinux-stable-22098763a10d9c1340827fcf6edab66f153b27f0.tar.gz
linux-stable-22098763a10d9c1340827fcf6edab66f153b27f0.zip
Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Don't destroy user event fields when removal fails User event fields are destroyed before the event is removed from visibility. But that can fail leaving the still visible event with no fields. Move the destroying of the fields to after the event is successfully removed from visibility. - Initialize function graph state is fork before calling copy_exec_state() For non-CLONE_VM forks, copy_exec_state() allocates a new task_exec_state. If that allocation fails, ftrace_graph_exit_task() will free the tasks ret_stack pointer. Since that pointer is still using the parent's ret_stack, it mistakenly frees the parent's pointer too. Call ftrace_graph_init() on the task first which will NULL out the new tasks's ret_stack and if the copy fails, it will not free anything. - Remove FGRAPH_MAX_INDEX The macro FGRAPH_MAX_INDEX was added but never used. Remove it. - Save ent_size in function graph printing of nested functions The function graph tracer needs to look at the next event to see if the next event is the return of the current function entry. If it is, it prints a single line: ktime_get(); Otherwise it prints it like a nested function: tick_nohz_irq_exit() { ktime_get(); kcpustat_irq_exit(); } In order to look at the next event, it must save the current event so that it has the information to print from it. It saves the event in the iterator descriptor called "ent". What it doesn't save is the ent_size of the event which is now used to know if the function graph arguments are to be printed. The peek doesn't save the size so the size used happens to be that of the size of the last event that was seen. Save the entry event size in the iterator descriptor so that the correct size is used. - Fix several errors with freeing data in the histogram code The histogram code had a lot of leaked or or incorrect accounting when failures happen. Correct them. - Fix histogram regression of .percent and .graph modifiers Up until 6.3 histogram values could have "percent" or "graph" modifiers that changed how they were printed. But a change that added restricting histograms values from being strings, stack traces and other modifiers inadvertently prevented them from using the percent and graph modifiers, which were legal use cases for values. Put back the percent and graph modifiers. - Fix various typos in the comments - Set the trace_clock before initializing a histogram with clock argument The histogram API allows the user to specific which trace clock to use via a "clock=" string. The histogram is set up first before the clock is checked. If the passed in clock is not valid, it exits without fully fixing up the histogram leaving it on the list and a use-after-free can trigger. Update the clock argument first and if it fails then exit gracefully before the histogram trigger is placed on any lists. - Restore :mod: trailer after parsing in ftrace_set_clr_event The function ftrace_set_clr_event() modifies the parse string and needs to put it back to what was passed in. It searches for ":mod:" via a strsep() but fails to put back the first ':' in the string. Add back the ':' in the passed in string. - Take trace_array reference when opening a tracer options file The options files are dynamically created and some tracers add their own options. When a tracer adds their own list of options, the trace_array holding them has an array to hold the list of options for each tracer. This array increases in size via a krealloc(), and the new entry gets a newly allocated array to hold the options of the new tracer being added. The element in each entry of the tracer's option array holds a pointer back to the trace_array, a pointer to the tracer it is associated to, a pointer to the flags of the option. The issue is that these arrays are freed when the trace_array is freed when its instance it represents is removed from the instances directory. There's a race that an open of one of these options files can happen when the instance is being removed. Add a new helper function to be called by the open function of the options file to iterate all existing trace_arrays under a lock and find the one that has the given option element in one of it's tracer arrays. If found, then update the associated trace_array's reference counter to keep it from being freed. If not found, have the open call return -ENODEV. - Disable interrupts when acquiring the lock in rb_wake_up_waiters() The function rb_wake_up_waiters() assumes it will be called in interrupt context and does not disable irqs when taking cpu_buffer->reader_lock, which can be called in hard interrupt context. The issue is in PREEMPT_RT, this function is called in thread context leaving this lock open to a deadlock. Take the lock with interrupts disabled. - Use rcu_assign_pointer() for tmp_ops filter hash The tmp_ops used in update_ftrace_direct_mod() assigns its filter_hash field directly, but that field is annotated as __rcu and sparse complains. Assign it with rcu_assign_pointer() - Fix use-after-free in enable_trigger_private_data_free() The trace_event_call is accessed through the event_trigger_data's trace_event_file pointer to put the trace_event_call on freeing. The issue is that the trace_event_file data may have been freed already causing a use-after-free. Add a field to the event_trigger_data that points directly to the trace_event_call so that it can decrement its reference directly without needing to go through the trace_event_file. - Fix accounting of buffer data remote headers trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount the number of pages is needed for the asked for size as it doesn't take into account the meta data on each page. Add a helper function to do the calculation properly and use that in these functions. - Catch nr_page_va overflow in ring_buffer_desc sizing The number of pages per remote ring buffer is capped by ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to overflow that field would silently allocate a descriptor smaller than what was asked for. - Do not resize the subbuf order if any per_cpu buffer is disabled The mmapping of ring buffers disables resizing the subbuffers, but it is done per-cpu whereas the subbuf size change is done for all the per_cpu buffers under the buffer->mutex. It could change the size of some while the mapping is happening on others. Have the resize of the subbuf order check all the per_cpu buffers under the lock to see if any of them is disabled before starting and causing an inconsistency between buffers that are being mapped. * tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits) ring-buffer: Check resize_disabled before publishing the new subbuf order tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing tracing/remotes: Account for ring buffer page header in size calculation tracing: Don't dereference trace_event_file in deferred trigger free ftrace: Use rcu_assign_pointer() for tmp_ops filter hash ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters() tracing: Take trace_array reference when opening a tracer options file tracing: Fix ring_buffer_read_page_size() kernel-doc tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event() tracing: Fix memory corruption from a "STACKTRACE" histogram key tracing: Fix memory corruption from the histogram stacktrace modifier tracing: Undo the registration when enabling the histogram trigger fails tracing: Take the reference before publishing the named histogram trigger tracing: Set the trace clock before registering the histogram trigger tracing: Fix typo "preceeded" in comment tracing: Fix typo "availabe" in comment tracing: Let histogram values keep the percent and graph modifiers tracing: Keep the entry count when the histogram stats allocation fails tracing: Free histogram the field rejected for a bad modifier tracing: Free histogram the var ref when its initialization fails ...
Diffstat (limited to 'drivers/clocksource/timer-sp804.c')
-rw-r--r--drivers/clocksource/timer-sp804.c418
1 files changed, 418 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-sp804.c b/drivers/clocksource/timer-sp804.c
new file mode 100644
index 000000000..d69858427
--- /dev/null
+++ b/drivers/clocksource/timer-sp804.c
@@ -0,0 +1,418 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * linux/drivers/clocksource/timer-sp.c
+ *
+ * Copyright (C) 1999 - 2003 ARM Limited
+ * Copyright (C) 2000 Deep Blue Solutions Ltd
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_clk.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#ifdef CONFIG_ARM
+#include <linux/delay.h>
+#endif
+
+#include "timer-sp.h"
+
+/* Hisilicon 64-bit timer(a variant of ARM SP804) */
+#define HISI_TIMER_1_BASE 0x00
+#define HISI_TIMER_2_BASE 0x40
+#define HISI_TIMER_LOAD 0x00
+#define HISI_TIMER_LOAD_H 0x04
+#define HISI_TIMER_VALUE 0x08
+#define HISI_TIMER_VALUE_H 0x0c
+#define HISI_TIMER_CTRL 0x10
+#define HISI_TIMER_INTCLR 0x14
+#define HISI_TIMER_RIS 0x18
+#define HISI_TIMER_MIS 0x1c
+#define HISI_TIMER_BGLOAD 0x20
+#define HISI_TIMER_BGLOAD_H 0x24
+
+static struct sp804_timer arm_sp804_timer __initdata = {
+ .load = TIMER_LOAD,
+ .value = TIMER_VALUE,
+ .ctrl = TIMER_CTRL,
+ .intclr = TIMER_INTCLR,
+ .timer_base = {TIMER_1_BASE, TIMER_2_BASE},
+ .width = 32,
+};
+
+static struct sp804_timer hisi_sp804_timer __initdata = {
+ .load = HISI_TIMER_LOAD,
+ .load_h = HISI_TIMER_LOAD_H,
+ .value = HISI_TIMER_VALUE,
+ .value_h = HISI_TIMER_VALUE_H,
+ .ctrl = HISI_TIMER_CTRL,
+ .intclr = HISI_TIMER_INTCLR,
+ .timer_base = {HISI_TIMER_1_BASE, HISI_TIMER_2_BASE},
+ .width = 64,
+};
+
+static struct sp804_clkevt sp804_clkevt[NR_TIMERS];
+
+static long __init sp804_get_clock_rate(struct clk *clk, const char *name)
+{
+ int err;
+
+ if (!clk)
+ clk = clk_get_sys("sp804", name);
+ if (IS_ERR(clk)) {
+ pr_err("%s clock not found: %ld\n", name, PTR_ERR(clk));
+ return PTR_ERR(clk);
+ }
+
+ err = clk_prepare_enable(clk);
+ if (err) {
+ pr_err("clock failed to enable: %d\n", err);
+ clk_put(clk);
+ return err;
+ }
+
+ return clk_get_rate(clk);
+}
+
+static struct sp804_clkevt * __init sp804_clkevt_get(void __iomem *base)
+{
+ int i;
+
+ for (i = 0; i < NR_TIMERS; i++) {
+ if (sp804_clkevt[i].base == base)
+ return &sp804_clkevt[i];
+ }
+
+ /* It's impossible to reach here */
+ WARN_ON(1);
+
+ return NULL;
+}
+
+static struct sp804_clkevt *sched_clkevt;
+
+static u64 notrace sp804_read(void)
+{
+ return ~readl_relaxed(sched_clkevt->value);
+}
+
+/* Register delay timer backed by the hardware counter */
+#ifdef CONFIG_ARM
+static struct delay_timer delay;
+static struct sp804_clkevt *delay_clkevt;
+
+static unsigned long sp804_read_delay_timer_read(void)
+{
+ return ~readl_relaxed(delay_clkevt->value);
+}
+
+static void sp804_register_delay_timer(struct sp804_clkevt *clk, int freq)
+{
+ delay_clkevt = clk;
+ delay.freq = freq;
+ delay.read_current_timer = sp804_read_delay_timer_read;
+ register_current_timer_delay(&delay);
+}
+#else
+static inline void sp804_register_delay_timer(struct sp804_clkevt *clk, int freq) {}
+#endif
+
+static int __init sp804_clocksource_and_sched_clock_init(void __iomem *base,
+ const char *name,
+ struct clk *clk,
+ int use_sched_clock)
+{
+ long rate;
+ struct sp804_clkevt *clkevt;
+
+ rate = sp804_get_clock_rate(clk, name);
+ if (rate < 0)
+ return -EINVAL;
+
+ clkevt = sp804_clkevt_get(base);
+
+ writel(0, clkevt->ctrl);
+ writel(0xffffffff, clkevt->load);
+ writel(0xffffffff, clkevt->value);
+ if (clkevt->width == 64) {
+ writel(0xffffffff, clkevt->load_h);
+ writel(0xffffffff, clkevt->value_h);
+ }
+ writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC,
+ clkevt->ctrl);
+
+ clocksource_mmio_init(clkevt->value, name,
+ rate, 200, 32, clocksource_mmio_readl_down);
+
+ sp804_register_delay_timer(clkevt, rate);
+
+ if (use_sched_clock) {
+ sched_clkevt = clkevt;
+ sched_clock_register(sp804_read, 32, rate);
+ }
+
+ return 0;
+}
+
+
+static struct sp804_clkevt *common_clkevt;
+
+/*
+ * IRQ handler for the timer
+ */
+static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ /* clear the interrupt */
+ writel(1, common_clkevt->intclr);
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static inline void evt_timer_shutdown(struct clock_event_device *evt)
+{
+ writel(0, common_clkevt->ctrl);
+}
+
+static int sp804_shutdown(struct clock_event_device *evt)
+{
+ evt_timer_shutdown(evt);
+ return 0;
+}
+
+static int sp804_set_periodic(struct clock_event_device *evt)
+{
+ unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
+ TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
+
+ evt_timer_shutdown(evt);
+ writel(common_clkevt->reload, common_clkevt->load);
+ writel(ctrl, common_clkevt->ctrl);
+ return 0;
+}
+
+static int sp804_set_next_event(unsigned long next,
+ struct clock_event_device *evt)
+{
+ unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
+ TIMER_CTRL_ONESHOT | TIMER_CTRL_ENABLE;
+
+ writel(next, common_clkevt->load);
+ writel(ctrl, common_clkevt->ctrl);
+
+ return 0;
+}
+
+static struct clock_event_device sp804_clockevent = {
+ .features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT |
+ CLOCK_EVT_FEAT_DYNIRQ,
+ .set_state_shutdown = sp804_shutdown,
+ .set_state_periodic = sp804_set_periodic,
+ .set_state_oneshot = sp804_shutdown,
+ .tick_resume = sp804_shutdown,
+ .set_next_event = sp804_set_next_event,
+ .rating = 300,
+};
+
+static int __init sp804_clockevents_init(void __iomem *base, unsigned int irq,
+ struct clk *clk, const char *name)
+{
+ struct clock_event_device *evt = &sp804_clockevent;
+ long rate;
+
+ rate = sp804_get_clock_rate(clk, name);
+ if (rate < 0)
+ return -EINVAL;
+
+ common_clkevt = sp804_clkevt_get(base);
+ common_clkevt->reload = DIV_ROUND_CLOSEST(rate, HZ);
+ evt->name = name;
+ evt->irq = irq;
+ evt->cpumask = cpu_possible_mask;
+
+ writel(0, common_clkevt->ctrl);
+
+ if (request_irq(irq, sp804_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+ "timer", &sp804_clockevent))
+ pr_err("request_irq() failed\n");
+ clockevents_config_and_register(evt, rate, 0xf, 0xffffffff);
+
+ return 0;
+}
+
+static void __init sp804_clkevt_init(struct sp804_timer *timer, void __iomem *base)
+{
+ int i;
+
+ for (i = 0; i < NR_TIMERS; i++) {
+ void __iomem *timer_base;
+ struct sp804_clkevt *clkevt;
+
+ timer_base = base + timer->timer_base[i];
+ clkevt = &sp804_clkevt[i];
+ clkevt->base = timer_base;
+ clkevt->load = timer_base + timer->load;
+ clkevt->load_h = timer_base + timer->load_h;
+ clkevt->value = timer_base + timer->value;
+ clkevt->value_h = timer_base + timer->value_h;
+ clkevt->ctrl = timer_base + timer->ctrl;
+ clkevt->intclr = timer_base + timer->intclr;
+ clkevt->width = timer->width;
+ }
+}
+
+static int __init sp804_of_init(struct device_node *np, struct sp804_timer *timer)
+{
+ static bool initialized = false;
+ void __iomem *base;
+ void __iomem *timer1_base;
+ void __iomem *timer2_base;
+ int irq, ret = -EINVAL;
+ u32 irq_num = 0;
+ struct clk *clk1, *clk2;
+ const char *name = of_get_property(np, "compatible", NULL);
+
+ if (initialized) {
+ pr_debug("%pOF: skipping further SP804 timer device\n", np);
+ return 0;
+ }
+
+ base = of_iomap(np, 0);
+ if (!base)
+ return -ENXIO;
+
+ timer1_base = base + timer->timer_base[0];
+ timer2_base = base + timer->timer_base[1];
+
+ /* Ensure timers are disabled */
+ writel(0, timer1_base + timer->ctrl);
+ writel(0, timer2_base + timer->ctrl);
+
+ clk1 = of_clk_get(np, 0);
+ if (IS_ERR(clk1))
+ clk1 = NULL;
+
+ /* Get the 2nd clock if the timer has 3 timer clocks */
+ if (of_clk_get_parent_count(np) == 3) {
+ clk2 = of_clk_get(np, 1);
+ if (IS_ERR(clk2)) {
+ pr_err("%pOFn clock not found: %d\n", np,
+ (int)PTR_ERR(clk2));
+ clk2 = NULL;
+ }
+ } else
+ clk2 = clk1;
+
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq <= 0)
+ goto err;
+
+ sp804_clkevt_init(timer, base);
+
+ of_property_read_u32(np, "arm,sp804-has-irq", &irq_num);
+ if (irq_num == 2) {
+
+ ret = sp804_clockevents_init(timer2_base, irq, clk2, name);
+ if (ret)
+ goto err;
+
+ ret = sp804_clocksource_and_sched_clock_init(timer1_base,
+ name, clk1, 1);
+ if (ret)
+ goto err;
+ } else {
+
+ ret = sp804_clockevents_init(timer1_base, irq, clk1, name);
+ if (ret)
+ goto err;
+
+ ret = sp804_clocksource_and_sched_clock_init(timer2_base,
+ name, clk2, 1);
+ if (ret)
+ goto err;
+ }
+
+ initialized = true;
+
+ return 0;
+err:
+ iounmap(base);
+ return ret;
+}
+
+static int __init arm_sp804_of_init(struct device_node *np)
+{
+ return sp804_of_init(np, &arm_sp804_timer);
+}
+TIMER_OF_DECLARE(sp804, "arm,sp804", arm_sp804_of_init);
+
+static int __init hisi_sp804_of_init(struct device_node *np)
+{
+ return sp804_of_init(np, &hisi_sp804_timer);
+}
+TIMER_OF_DECLARE(hisi_sp804, "hisilicon,sp804", hisi_sp804_of_init);
+
+static int __init integrator_cp_of_init(struct device_node *np)
+{
+ static int init_count = 0;
+ void __iomem *base;
+ int irq, ret = -EINVAL;
+ const char *name = of_get_property(np, "compatible", NULL);
+ struct clk *clk;
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ pr_err("Failed to iomap\n");
+ return -ENXIO;
+ }
+
+ clk = of_clk_get(np, 0);
+ if (IS_ERR(clk)) {
+ pr_err("Failed to get clock\n");
+ return PTR_ERR(clk);
+ }
+
+ /* Ensure timer is disabled */
+ writel(0, base + arm_sp804_timer.ctrl);
+
+ if (init_count == 2 || !of_device_is_available(np))
+ goto err;
+
+ sp804_clkevt_init(&arm_sp804_timer, base);
+
+ if (!init_count) {
+ ret = sp804_clocksource_and_sched_clock_init(base,
+ name, clk, 0);
+ if (ret)
+ goto err;
+ } else {
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq <= 0)
+ goto err;
+
+ ret = sp804_clockevents_init(base, irq, clk, name);
+ if (ret)
+ goto err;
+ }
+
+ init_count++;
+ return 0;
+err:
+ iounmap(base);
+ return ret;
+}
+TIMER_OF_DECLARE(intcp, "arm,integrator-cp-timer", integrator_cp_of_init);