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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /drivers/clocksource/timer-gxp.c
downloadlinux-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/timer-gxp.c')
-rw-r--r--drivers/clocksource/timer-gxp.c215
1 files changed, 215 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-gxp.c b/drivers/clocksource/timer-gxp.c
new file mode 100644
index 000000000..1becc9433
--- /dev/null
+++ b/drivers/clocksource/timer-gxp.c
@@ -0,0 +1,215 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2022 Hewlett-Packard Enterprise Development Company, L.P. */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/sched_clock.h>
+
+#define TIMER0_FREQ 1000000
+#define GXP_TIMER_CNT_OFS 0x00
+#define GXP_TIMESTAMP_OFS 0x08
+#define GXP_TIMER_CTRL_OFS 0x14
+
+/* TCS Stands for Timer Control/Status: these are masks to be used in */
+/* the Timer Count Registers */
+#define MASK_TCS_ENABLE 0x01
+#define MASK_TCS_PERIOD 0x02
+#define MASK_TCS_RELOAD 0x04
+#define MASK_TCS_TC 0x80
+
+struct gxp_timer {
+ void __iomem *counter;
+ void __iomem *control;
+ struct clock_event_device evt;
+};
+
+static struct gxp_timer *gxp_timer;
+
+static void __iomem *system_clock __ro_after_init;
+
+static inline struct gxp_timer *to_gxp_timer(struct clock_event_device *evt_dev)
+{
+ return container_of(evt_dev, struct gxp_timer, evt);
+}
+
+static u64 notrace gxp_sched_read(void)
+{
+ return readl_relaxed(system_clock);
+}
+
+static int gxp_time_set_next_event(unsigned long event, struct clock_event_device *evt_dev)
+{
+ struct gxp_timer *timer = to_gxp_timer(evt_dev);
+
+ /* Stop counting and disable interrupt before updating */
+ writeb_relaxed(MASK_TCS_TC, timer->control);
+ writel_relaxed(event, timer->counter);
+ writeb_relaxed(MASK_TCS_TC | MASK_TCS_ENABLE, timer->control);
+
+ return 0;
+}
+
+static irqreturn_t gxp_timer_interrupt(int irq, void *dev_id)
+{
+ struct gxp_timer *timer = (struct gxp_timer *)dev_id;
+
+ if (!(readb_relaxed(timer->control) & MASK_TCS_TC))
+ return IRQ_NONE;
+
+ writeb_relaxed(MASK_TCS_TC, timer->control);
+
+ timer->evt.event_handler(&timer->evt);
+
+ return IRQ_HANDLED;
+}
+
+static int __init gxp_timer_init(struct device_node *node)
+{
+ void __iomem *base;
+ struct clk *clk;
+ u32 freq;
+ int ret, irq;
+
+ gxp_timer = kzalloc_obj(*gxp_timer);
+ if (!gxp_timer) {
+ ret = -ENOMEM;
+ pr_err("Can't allocate gxp_timer");
+ return ret;
+ }
+
+ clk = of_clk_get(node, 0);
+ if (IS_ERR(clk)) {
+ ret = PTR_ERR(clk);
+ pr_err("%pOFn clock not found: %d\n", node, ret);
+ goto err_free;
+ }
+
+ ret = clk_prepare_enable(clk);
+ if (ret) {
+ pr_err("%pOFn clock enable failed: %d\n", node, ret);
+ goto err_clk_enable;
+ }
+
+ base = of_iomap(node, 0);
+ if (!base) {
+ ret = -ENXIO;
+ pr_err("Can't map timer base registers");
+ goto err_iomap;
+ }
+
+ /* Set the offsets to the clock register and timer registers */
+ gxp_timer->counter = base + GXP_TIMER_CNT_OFS;
+ gxp_timer->control = base + GXP_TIMER_CTRL_OFS;
+ system_clock = base + GXP_TIMESTAMP_OFS;
+
+ gxp_timer->evt.name = node->name;
+ gxp_timer->evt.rating = 300;
+ gxp_timer->evt.features = CLOCK_EVT_FEAT_ONESHOT;
+ gxp_timer->evt.set_next_event = gxp_time_set_next_event;
+ gxp_timer->evt.cpumask = cpumask_of(0);
+
+ irq = irq_of_parse_and_map(node, 0);
+ if (irq <= 0) {
+ ret = -EINVAL;
+ pr_err("GXP Timer Can't parse IRQ %d", irq);
+ goto err_exit;
+ }
+
+ freq = clk_get_rate(clk);
+
+ ret = clocksource_mmio_init(system_clock, node->name, freq,
+ 300, 32, clocksource_mmio_readl_up);
+ if (ret) {
+ pr_err("%pOFn init clocksource failed: %d", node, ret);
+ goto err_exit;
+ }
+
+ sched_clock_register(gxp_sched_read, 32, freq);
+
+ irq = irq_of_parse_and_map(node, 0);
+ if (irq <= 0) {
+ ret = -EINVAL;
+ pr_err("%pOFn Can't parse IRQ %d", node, irq);
+ goto err_exit;
+ }
+
+ clockevents_config_and_register(&gxp_timer->evt, TIMER0_FREQ,
+ 0xf, 0xffffffff);
+
+ ret = request_irq(irq, gxp_timer_interrupt, IRQF_TIMER | IRQF_SHARED,
+ node->name, gxp_timer);
+ if (ret) {
+ pr_err("%pOFn request_irq() failed: %d", node, ret);
+ goto err_exit;
+ }
+
+ pr_debug("gxp: system timer (irq = %d)\n", irq);
+ return 0;
+
+err_exit:
+ iounmap(base);
+err_iomap:
+ clk_disable_unprepare(clk);
+err_clk_enable:
+ clk_put(clk);
+err_free:
+ kfree(gxp_timer);
+ return ret;
+}
+
+/*
+ * This probe gets called after the timer is already up and running. This will create
+ * the watchdog device as a child since the registers are shared.
+ */
+
+static int gxp_timer_probe(struct platform_device *pdev)
+{
+ struct platform_device *gxp_watchdog_device;
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ if (!gxp_timer) {
+ pr_err("Gxp Timer not initialized, cannot create watchdog");
+ return -ENOMEM;
+ }
+
+ gxp_watchdog_device = platform_device_alloc("gxp-wdt", -1);
+ if (!gxp_watchdog_device) {
+ pr_err("Timer failed to allocate gxp-wdt");
+ return -ENOMEM;
+ }
+
+ /* Pass the base address (counter) as platform data and nothing else */
+ gxp_watchdog_device->dev.platform_data = gxp_timer->counter;
+ gxp_watchdog_device->dev.parent = dev;
+
+ ret = platform_device_add(gxp_watchdog_device);
+ if (ret)
+ platform_device_put(gxp_watchdog_device);
+
+ return ret;
+}
+
+static const struct of_device_id gxp_timer_of_match[] = {
+ { .compatible = "hpe,gxp-timer", },
+ {},
+};
+
+static struct platform_driver gxp_timer_driver = {
+ .probe = gxp_timer_probe,
+ .driver = {
+ .name = "gxp-timer",
+ .of_match_table = gxp_timer_of_match,
+ .suppress_bind_attrs = true,
+ },
+};
+
+builtin_platform_driver(gxp_timer_driver);
+
+TIMER_OF_DECLARE(gxp, "hpe,gxp-timer", gxp_timer_init);