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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/clocksource/timer-sp804.c
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
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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/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);