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| author | Niklas Cassel <cassel@kernel.org> | 2026-09-16 15:00:32 +0200 |
|---|---|---|
| committer | Niklas Cassel <cassel@kernel.org> | 2026-09-16 16:18:00 +0200 |
| commit | 8d836581f9b1f57ceaa2b47654754ef1260b410b (patch) | |
| tree | 1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /drivers/clocksource/mps2-timer.c | |
| download | linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip | |
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with:
Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301:
ERROR: Unexpected indentation. [docutils]
The Return: section of ata_dsm_trim_pages() ends its first sentence with
a colon and continues with an indented bullet list. reStructuredText
requires a blank line before an indented block, so docutils chokes on
the list.
Simply adding the missing blank line does not work either: Return: is a
kernel-doc "special section", which is terminated by the first blank
line, so the bullet list would end up in the Description section,
detached from the sentence introducing it.
Spell the two bounds out as prose instead, so that the Return: section
stays self-contained. Documentation-only change.
Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND")
Reported-by: Thomas Huth <thuth@redhat.com>
Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'drivers/clocksource/mps2-timer.c')
| -rw-r--r-- | drivers/clocksource/mps2-timer.c | 273 |
1 files changed, 273 insertions, 0 deletions
diff --git a/drivers/clocksource/mps2-timer.c b/drivers/clocksource/mps2-timer.c new file mode 100644 index 000000000..ebca55d8c --- /dev/null +++ b/drivers/clocksource/mps2-timer.c @@ -0,0 +1,273 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2015 ARM Limited + * + * Author: Vladimir Murzin <vladimir.murzin@arm.com> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/clk.h> +#include <linux/clockchips.h> +#include <linux/clocksource.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/of_address.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/sched_clock.h> +#include <linux/slab.h> + +#define TIMER_CTRL 0x0 +#define TIMER_CTRL_ENABLE BIT(0) +#define TIMER_CTRL_IE BIT(3) + +#define TIMER_VALUE 0x4 +#define TIMER_RELOAD 0x8 +#define TIMER_INT 0xc + +struct clockevent_mps2 { + void __iomem *reg; + u32 clock_count_per_tick; + struct clock_event_device clkevt; +}; + +static void __iomem *sched_clock_base; + +static u64 notrace mps2_sched_read(void) +{ + return ~readl_relaxed(sched_clock_base + TIMER_VALUE); +} + +static inline struct clockevent_mps2 *to_mps2_clkevt(struct clock_event_device *c) +{ + return container_of(c, struct clockevent_mps2, clkevt); +} + +static void clockevent_mps2_writel(u32 val, struct clock_event_device *c, u32 offset) +{ + writel_relaxed(val, to_mps2_clkevt(c)->reg + offset); +} + +static int mps2_timer_shutdown(struct clock_event_device *ce) +{ + clockevent_mps2_writel(0, ce, TIMER_RELOAD); + clockevent_mps2_writel(0, ce, TIMER_CTRL); + + return 0; +} + +static int mps2_timer_set_next_event(unsigned long next, struct clock_event_device *ce) +{ + clockevent_mps2_writel(next, ce, TIMER_VALUE); + clockevent_mps2_writel(TIMER_CTRL_IE | TIMER_CTRL_ENABLE, ce, TIMER_CTRL); + + return 0; +} + +static int mps2_timer_set_periodic(struct clock_event_device *ce) +{ + u32 clock_count_per_tick = to_mps2_clkevt(ce)->clock_count_per_tick; + + clockevent_mps2_writel(clock_count_per_tick, ce, TIMER_RELOAD); + clockevent_mps2_writel(clock_count_per_tick, ce, TIMER_VALUE); + clockevent_mps2_writel(TIMER_CTRL_IE | TIMER_CTRL_ENABLE, ce, TIMER_CTRL); + + return 0; +} + +static irqreturn_t mps2_timer_interrupt(int irq, void *dev_id) +{ + struct clockevent_mps2 *ce = dev_id; + u32 status = readl_relaxed(ce->reg + TIMER_INT); + + if (!status) { + pr_warn("spurious interrupt\n"); + return IRQ_NONE; + } + + writel_relaxed(1, ce->reg + TIMER_INT); + + ce->clkevt.event_handler(&ce->clkevt); + + return IRQ_HANDLED; +} + +static int __init mps2_clockevent_init(struct device_node *np) +{ + void __iomem *base; + struct clk *clk = NULL; + struct clockevent_mps2 *ce; + u32 rate; + int irq, ret; + const char *name = "mps2-clkevt"; + + ret = of_property_read_u32(np, "clock-frequency", &rate); + if (ret) { + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + pr_err("failed to get clock for clockevent: %d\n", ret); + goto out; + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable clock for clockevent: %d\n", ret); + goto out_clk_put; + } + + rate = clk_get_rate(clk); + } + + base = of_iomap(np, 0); + if (!base) { + ret = -EADDRNOTAVAIL; + pr_err("failed to map register for clockevent: %d\n", ret); + goto out_clk_disable; + } + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + ret = -ENOENT; + pr_err("failed to get irq for clockevent: %d\n", ret); + goto out_iounmap; + } + + ce = kzalloc_obj(*ce); + if (!ce) { + ret = -ENOMEM; + goto out_iounmap; + } + + ce->reg = base; + ce->clock_count_per_tick = DIV_ROUND_CLOSEST(rate, HZ); + ce->clkevt.irq = irq; + ce->clkevt.name = name; + ce->clkevt.rating = 200; + ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + ce->clkevt.cpumask = cpu_possible_mask; + ce->clkevt.set_state_shutdown = mps2_timer_shutdown; + ce->clkevt.set_state_periodic = mps2_timer_set_periodic; + ce->clkevt.set_state_oneshot = mps2_timer_shutdown; + ce->clkevt.set_next_event = mps2_timer_set_next_event; + + /* Ensure timer is disabled */ + writel_relaxed(0, base + TIMER_CTRL); + + ret = request_irq(irq, mps2_timer_interrupt, IRQF_TIMER, name, ce); + if (ret) { + pr_err("failed to request irq for clockevent: %d\n", ret); + goto out_kfree; + } + + clockevents_config_and_register(&ce->clkevt, rate, 0xf, 0xffffffff); + + return 0; + +out_kfree: + kfree(ce); +out_iounmap: + iounmap(base); +out_clk_disable: + /* clk_{disable, unprepare, put}() can handle NULL as a parameter */ + clk_disable_unprepare(clk); +out_clk_put: + clk_put(clk); +out: + return ret; +} + +static int __init mps2_clocksource_init(struct device_node *np) +{ + void __iomem *base; + struct clk *clk = NULL; + u32 rate; + int ret; + const char *name = "mps2-clksrc"; + + ret = of_property_read_u32(np, "clock-frequency", &rate); + if (ret) { + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + pr_err("failed to get clock for clocksource: %d\n", ret); + goto out; + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable clock for clocksource: %d\n", ret); + goto out_clk_put; + } + + rate = clk_get_rate(clk); + } + + base = of_iomap(np, 0); + if (!base) { + ret = -EADDRNOTAVAIL; + pr_err("failed to map register for clocksource: %d\n", ret); + goto out_clk_disable; + } + + /* Ensure timer is disabled */ + writel_relaxed(0, base + TIMER_CTRL); + + /* ... and set it up as free-running clocksource */ + writel_relaxed(0xffffffff, base + TIMER_VALUE); + writel_relaxed(0xffffffff, base + TIMER_RELOAD); + + writel_relaxed(TIMER_CTRL_ENABLE, base + TIMER_CTRL); + + ret = clocksource_mmio_init(base + TIMER_VALUE, name, + rate, 200, 32, + clocksource_mmio_readl_down); + if (ret) { + pr_err("failed to init clocksource: %d\n", ret); + goto out_iounmap; + } + + sched_clock_base = base; + sched_clock_register(mps2_sched_read, 32, rate); + + return 0; + +out_iounmap: + iounmap(base); +out_clk_disable: + /* clk_{disable, unprepare, put}() can handle NULL as a parameter */ + clk_disable_unprepare(clk); +out_clk_put: + clk_put(clk); +out: + return ret; +} + +static int __init mps2_timer_init(struct device_node *np) +{ + static int has_clocksource, has_clockevent; + int ret; + + if (!has_clocksource) { + ret = mps2_clocksource_init(np); + if (!ret) { + has_clocksource = 1; + return 0; + } + } + + if (!has_clockevent) { + ret = mps2_clockevent_init(np); + if (!ret) { + has_clockevent = 1; + return 0; + } + } + + return 0; +} + +TIMER_OF_DECLARE(mps2_timer, "arm,mps2-timer", mps2_timer_init); |
