diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-30 09:22:00 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-30 09:22:00 -0700 |
| commit | 034dd340b08be1f2f0477ad16131d609f9dbd53c (patch) | |
| tree | 2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/clocksource/timer-imx-gpt.c | |
| download | linux-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/clocksource/timer-imx-gpt.c')
| -rw-r--r-- | drivers/clocksource/timer-imx-gpt.c | 511 |
1 files changed, 511 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-imx-gpt.c b/drivers/clocksource/timer-imx-gpt.c new file mode 100644 index 000000000..8335bd7f8 --- /dev/null +++ b/drivers/clocksource/timer-imx-gpt.c @@ -0,0 +1,511 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// Copyright (C) 2000-2001 Deep Blue Solutions +// Copyright (C) 2002 Shane Nay (shane@minirl.com) +// Copyright (C) 2006-2007 Pavel Pisa (ppisa@pikron.com) +// Copyright (C) 2008 Juergen Beisert (kernel@pengutronix.de) + +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/clockchips.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/sched_clock.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> + +/* + * There are 4 versions of the timer hardware on Freescale MXC hardware. + * - MX1/MXL + * - MX21, MX27. + * - MX25, MX31, MX35, MX37, MX51, MX6Q(rev1.0) + * - MX6DL, MX6SX, MX6Q(rev1.1+) + */ +enum imx_gpt_type { + GPT_TYPE_IMX1, /* i.MX1 */ + GPT_TYPE_IMX21, /* i.MX21/27 */ + GPT_TYPE_IMX31, /* i.MX31/35/25/37/51/6Q */ + GPT_TYPE_IMX6DL, /* i.MX6DL/SX/SL */ +}; + +/* defines common for all i.MX */ +#define MXC_TCTL 0x00 +#define MXC_TCTL_TEN (1 << 0) /* Enable module */ +#define MXC_TPRER 0x04 + +/* MX1, MX21, MX27 */ +#define MX1_2_TCTL_CLK_PCLK1 (1 << 1) +#define MX1_2_TCTL_IRQEN (1 << 4) +#define MX1_2_TCTL_FRR (1 << 8) +#define MX1_2_TCMP 0x08 +#define MX1_2_TCN 0x10 +#define MX1_2_TSTAT 0x14 + +/* MX21, MX27 */ +#define MX2_TSTAT_CAPT (1 << 1) +#define MX2_TSTAT_COMP (1 << 0) + +/* MX31, MX35, MX25, MX5, MX6 */ +#define V2_TCTL_WAITEN (1 << 3) /* Wait enable mode */ +#define V2_TCTL_CLK_IPG (1 << 6) +#define V2_TCTL_CLK_PER (2 << 6) +#define V2_TCTL_CLK_OSC_DIV8 (5 << 6) +#define V2_TCTL_FRR (1 << 9) +#define V2_TCTL_24MEN (1 << 10) +#define V2_TPRER_PRE24M 12 +#define V2_IR 0x0c +#define V2_TSTAT 0x08 +#define V2_TSTAT_OF1 (1 << 0) +#define V2_TCN 0x24 +#define V2_TCMP 0x10 + +#define V2_TIMER_RATE_OSC_DIV8 3000000 + +struct imx_timer { + enum imx_gpt_type type; + void __iomem *base; + int irq; + struct clk *clk_per; + struct clk *clk_ipg; + const struct imx_gpt_data *gpt; + struct clock_event_device ced; +}; + +struct imx_gpt_data { + int reg_tstat; + int reg_tcn; + int reg_tcmp; + void (*gpt_setup_tctl)(struct imx_timer *imxtm); + void (*gpt_irq_enable)(struct imx_timer *imxtm); + void (*gpt_irq_disable)(struct imx_timer *imxtm); + void (*gpt_irq_acknowledge)(struct imx_timer *imxtm); + int (*set_next_event)(unsigned long evt, + struct clock_event_device *ced); +}; + +static inline struct imx_timer *to_imx_timer(struct clock_event_device *ced) +{ + return container_of(ced, struct imx_timer, ced); +} + +static void imx1_gpt_irq_disable(struct imx_timer *imxtm) +{ + unsigned int tmp; + + tmp = readl_relaxed(imxtm->base + MXC_TCTL); + writel_relaxed(tmp & ~MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL); +} + +static void imx31_gpt_irq_disable(struct imx_timer *imxtm) +{ + writel_relaxed(0, imxtm->base + V2_IR); +} + +static void imx1_gpt_irq_enable(struct imx_timer *imxtm) +{ + unsigned int tmp; + + tmp = readl_relaxed(imxtm->base + MXC_TCTL); + writel_relaxed(tmp | MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL); +} + +static void imx31_gpt_irq_enable(struct imx_timer *imxtm) +{ + writel_relaxed(1<<0, imxtm->base + V2_IR); +} + +static void imx1_gpt_irq_acknowledge(struct imx_timer *imxtm) +{ + writel_relaxed(0, imxtm->base + MX1_2_TSTAT); +} + +static void imx21_gpt_irq_acknowledge(struct imx_timer *imxtm) +{ + writel_relaxed(MX2_TSTAT_CAPT | MX2_TSTAT_COMP, + imxtm->base + MX1_2_TSTAT); +} + +static void imx31_gpt_irq_acknowledge(struct imx_timer *imxtm) +{ + writel_relaxed(V2_TSTAT_OF1, imxtm->base + V2_TSTAT); +} + +static void __iomem *sched_clock_reg; + +static u64 notrace mxc_read_sched_clock(void) +{ + return sched_clock_reg ? readl_relaxed(sched_clock_reg) : 0; +} + +#if defined(CONFIG_ARM) +static struct delay_timer imx_delay_timer; + +static unsigned long imx_read_current_timer(void) +{ + return readl_relaxed(sched_clock_reg); +} +#endif + +static int __init mxc_clocksource_init(struct imx_timer *imxtm) +{ + unsigned int c = clk_get_rate(imxtm->clk_per); + void __iomem *reg = imxtm->base + imxtm->gpt->reg_tcn; + +#if defined(CONFIG_ARM) + imx_delay_timer.read_current_timer = &imx_read_current_timer; + imx_delay_timer.freq = c; + register_current_timer_delay(&imx_delay_timer); +#endif + + sched_clock_reg = reg; + + sched_clock_register(mxc_read_sched_clock, 32, c); + return clocksource_mmio_init(reg, "mxc_timer1", c, 200, 32, + clocksource_mmio_readl_up); +} + +/* clock event */ + +static int mx1_2_set_next_event(unsigned long evt, + struct clock_event_device *ced) +{ + struct imx_timer *imxtm = to_imx_timer(ced); + unsigned long tcmp; + + tcmp = readl_relaxed(imxtm->base + MX1_2_TCN) + evt; + + writel_relaxed(tcmp, imxtm->base + MX1_2_TCMP); + + return (int)(tcmp - readl_relaxed(imxtm->base + MX1_2_TCN)) < 0 ? + -ETIME : 0; +} + +static int v2_set_next_event(unsigned long evt, + struct clock_event_device *ced) +{ + struct imx_timer *imxtm = to_imx_timer(ced); + unsigned long tcmp; + + tcmp = readl_relaxed(imxtm->base + V2_TCN) + evt; + + writel_relaxed(tcmp, imxtm->base + V2_TCMP); + + return evt < 0x7fffffff && + (int)(tcmp - readl_relaxed(imxtm->base + V2_TCN)) < 0 ? + -ETIME : 0; +} + +static int mxc_shutdown(struct clock_event_device *ced) +{ + struct imx_timer *imxtm = to_imx_timer(ced); + u32 tcn; + + /* Disable interrupt in GPT module */ + imxtm->gpt->gpt_irq_disable(imxtm); + + tcn = readl_relaxed(imxtm->base + imxtm->gpt->reg_tcn); + /* Set event time into far-far future */ + writel_relaxed(tcn - 3, imxtm->base + imxtm->gpt->reg_tcmp); + + /* Clear pending interrupt */ + imxtm->gpt->gpt_irq_acknowledge(imxtm); + +#ifdef DEBUG + printk(KERN_INFO "%s: changing mode\n", __func__); +#endif /* DEBUG */ + + return 0; +} + +static int mxc_set_oneshot(struct clock_event_device *ced) +{ + struct imx_timer *imxtm = to_imx_timer(ced); + + /* Disable interrupt in GPT module */ + imxtm->gpt->gpt_irq_disable(imxtm); + + if (!clockevent_state_oneshot(ced)) { + u32 tcn = readl_relaxed(imxtm->base + imxtm->gpt->reg_tcn); + /* Set event time into far-far future */ + writel_relaxed(tcn - 3, imxtm->base + imxtm->gpt->reg_tcmp); + + /* Clear pending interrupt */ + imxtm->gpt->gpt_irq_acknowledge(imxtm); + } + +#ifdef DEBUG + printk(KERN_INFO "%s: changing mode\n", __func__); +#endif /* DEBUG */ + + /* + * Do not put overhead of interrupt enable/disable into + * mxc_set_next_event(), the core has about 4 minutes + * to call mxc_set_next_event() or shutdown clock after + * mode switching + */ + imxtm->gpt->gpt_irq_enable(imxtm); + + return 0; +} + +/* + * IRQ handler for the timer + */ +static irqreturn_t mxc_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *ced = dev_id; + struct imx_timer *imxtm = to_imx_timer(ced); + + readl_relaxed(imxtm->base + imxtm->gpt->reg_tstat); + + imxtm->gpt->gpt_irq_acknowledge(imxtm); + + ced->event_handler(ced); + + return IRQ_HANDLED; +} + +static int __init mxc_clockevent_init(struct imx_timer *imxtm) +{ + struct clock_event_device *ced = &imxtm->ced; + + ced->name = "mxc_timer1"; + ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ; + ced->set_state_shutdown = mxc_shutdown; + ced->set_state_oneshot = mxc_set_oneshot; + ced->tick_resume = mxc_shutdown; + ced->set_next_event = imxtm->gpt->set_next_event; + ced->rating = 200; + ced->cpumask = cpumask_of(0); + ced->irq = imxtm->irq; + clockevents_config_and_register(ced, clk_get_rate(imxtm->clk_per), + 0xff, 0xfffffffe); + + return request_irq(imxtm->irq, mxc_timer_interrupt, + IRQF_TIMER | IRQF_IRQPOLL, "i.MX Timer Tick", ced); +} + +static void imx1_gpt_setup_tctl(struct imx_timer *imxtm) +{ + u32 tctl_val; + + tctl_val = MX1_2_TCTL_FRR | MX1_2_TCTL_CLK_PCLK1 | MXC_TCTL_TEN; + writel_relaxed(tctl_val, imxtm->base + MXC_TCTL); +} + +static void imx31_gpt_setup_tctl(struct imx_timer *imxtm) +{ + u32 tctl_val; + + tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN; + if (clk_get_rate(imxtm->clk_per) == V2_TIMER_RATE_OSC_DIV8) + tctl_val |= V2_TCTL_CLK_OSC_DIV8; + else + tctl_val |= V2_TCTL_CLK_PER; + + writel_relaxed(tctl_val, imxtm->base + MXC_TCTL); +} + +static void imx6dl_gpt_setup_tctl(struct imx_timer *imxtm) +{ + u32 tctl_val; + + tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN; + if (clk_get_rate(imxtm->clk_per) == V2_TIMER_RATE_OSC_DIV8) { + tctl_val |= V2_TCTL_CLK_OSC_DIV8; + /* 24 / 8 = 3 MHz */ + writel_relaxed(7 << V2_TPRER_PRE24M, imxtm->base + MXC_TPRER); + tctl_val |= V2_TCTL_24MEN; + } else { + tctl_val |= V2_TCTL_CLK_PER; + } + + writel_relaxed(tctl_val, imxtm->base + MXC_TCTL); +} + +static const struct imx_gpt_data imx1_gpt_data = { + .reg_tstat = MX1_2_TSTAT, + .reg_tcn = MX1_2_TCN, + .reg_tcmp = MX1_2_TCMP, + .gpt_irq_enable = imx1_gpt_irq_enable, + .gpt_irq_disable = imx1_gpt_irq_disable, + .gpt_irq_acknowledge = imx1_gpt_irq_acknowledge, + .gpt_setup_tctl = imx1_gpt_setup_tctl, + .set_next_event = mx1_2_set_next_event, +}; + +static const struct imx_gpt_data imx21_gpt_data = { + .reg_tstat = MX1_2_TSTAT, + .reg_tcn = MX1_2_TCN, + .reg_tcmp = MX1_2_TCMP, + .gpt_irq_enable = imx1_gpt_irq_enable, + .gpt_irq_disable = imx1_gpt_irq_disable, + .gpt_irq_acknowledge = imx21_gpt_irq_acknowledge, + .gpt_setup_tctl = imx1_gpt_setup_tctl, + .set_next_event = mx1_2_set_next_event, +}; + +static const struct imx_gpt_data imx31_gpt_data = { + .reg_tstat = V2_TSTAT, + .reg_tcn = V2_TCN, + .reg_tcmp = V2_TCMP, + .gpt_irq_enable = imx31_gpt_irq_enable, + .gpt_irq_disable = imx31_gpt_irq_disable, + .gpt_irq_acknowledge = imx31_gpt_irq_acknowledge, + .gpt_setup_tctl = imx31_gpt_setup_tctl, + .set_next_event = v2_set_next_event, +}; + +static const struct imx_gpt_data imx6dl_gpt_data = { + .reg_tstat = V2_TSTAT, + .reg_tcn = V2_TCN, + .reg_tcmp = V2_TCMP, + .gpt_irq_enable = imx31_gpt_irq_enable, + .gpt_irq_disable = imx31_gpt_irq_disable, + .gpt_irq_acknowledge = imx31_gpt_irq_acknowledge, + .gpt_setup_tctl = imx6dl_gpt_setup_tctl, + .set_next_event = v2_set_next_event, +}; + +static int __init _mxc_timer_init(struct imx_timer *imxtm) +{ + int ret; + + switch (imxtm->type) { + case GPT_TYPE_IMX1: + imxtm->gpt = &imx1_gpt_data; + break; + case GPT_TYPE_IMX21: + imxtm->gpt = &imx21_gpt_data; + break; + case GPT_TYPE_IMX31: + imxtm->gpt = &imx31_gpt_data; + break; + case GPT_TYPE_IMX6DL: + imxtm->gpt = &imx6dl_gpt_data; + break; + default: + return -EINVAL; + } + + if (IS_ERR(imxtm->clk_per)) { + pr_err("i.MX timer: unable to get clk\n"); + return PTR_ERR(imxtm->clk_per); + } + + if (!IS_ERR(imxtm->clk_ipg)) + clk_prepare_enable(imxtm->clk_ipg); + + clk_prepare_enable(imxtm->clk_per); + + /* + * Initialise to a known state (all timers off, and timing reset) + */ + + writel_relaxed(0, imxtm->base + MXC_TCTL); + writel_relaxed(0, imxtm->base + MXC_TPRER); /* see datasheet note */ + + imxtm->gpt->gpt_setup_tctl(imxtm); + + /* init and register the timer to the framework */ + ret = mxc_clocksource_init(imxtm); + if (ret) + return ret; + + return mxc_clockevent_init(imxtm); +} + +static int __init mxc_timer_init_dt(struct device_node *np, enum imx_gpt_type type) +{ + struct imx_timer *imxtm; + static int initialized; + int ret; + + /* Support one instance only */ + if (initialized) + return 0; + + imxtm = kzalloc_obj(*imxtm); + if (!imxtm) + return -ENOMEM; + + imxtm->base = of_iomap(np, 0); + if (!imxtm->base) { + ret = -ENXIO; + goto err_kfree; + } + + imxtm->irq = irq_of_parse_and_map(np, 0); + if (imxtm->irq <= 0) { + ret = -EINVAL; + goto err_kfree; + } + + imxtm->clk_ipg = of_clk_get_by_name(np, "ipg"); + + /* Try osc_per first, and fall back to per otherwise */ + imxtm->clk_per = of_clk_get_by_name(np, "osc_per"); + if (IS_ERR(imxtm->clk_per)) + imxtm->clk_per = of_clk_get_by_name(np, "per"); + + imxtm->type = type; + + ret = _mxc_timer_init(imxtm); + if (ret) + goto err_kfree; + + initialized = 1; + + return 0; + +err_kfree: + kfree(imxtm); + return ret; +} + +static int __init imx1_timer_init_dt(struct device_node *np) +{ + return mxc_timer_init_dt(np, GPT_TYPE_IMX1); +} + +static int __init imx21_timer_init_dt(struct device_node *np) +{ + return mxc_timer_init_dt(np, GPT_TYPE_IMX21); +} + +static int __init imx31_timer_init_dt(struct device_node *np) +{ + enum imx_gpt_type type = GPT_TYPE_IMX31; + + /* + * We were using the same compatible string for i.MX6Q/D and i.MX6DL/S + * GPT device, while they actually have different programming model. + * This is a workaround to keep the existing i.MX6DL/S DTBs continue + * working with the new kernel. + */ + if (of_machine_is_compatible("fsl,imx6dl")) + type = GPT_TYPE_IMX6DL; + + return mxc_timer_init_dt(np, type); +} + +static int __init imx6dl_timer_init_dt(struct device_node *np) +{ + return mxc_timer_init_dt(np, GPT_TYPE_IMX6DL); +} + +TIMER_OF_DECLARE(imx1_timer, "fsl,imx1-gpt", imx1_timer_init_dt); +TIMER_OF_DECLARE(imx21_timer, "fsl,imx21-gpt", imx21_timer_init_dt); +TIMER_OF_DECLARE(imx27_timer, "fsl,imx27-gpt", imx21_timer_init_dt); +TIMER_OF_DECLARE(imx31_timer, "fsl,imx31-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx25_timer, "fsl,imx25-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx50_timer, "fsl,imx50-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx51_timer, "fsl,imx51-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx53_timer, "fsl,imx53-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx6q_timer, "fsl,imx6q-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx6dl_timer, "fsl,imx6dl-gpt", imx6dl_timer_init_dt); +TIMER_OF_DECLARE(imx6sl_timer, "fsl,imx6sl-gpt", imx6dl_timer_init_dt); +TIMER_OF_DECLARE(imx6sx_timer, "fsl,imx6sx-gpt", imx6dl_timer_init_dt); 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