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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /drivers/clocksource/timer-vt8500.c
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'drivers/clocksource/timer-vt8500.c')
-rw-r--r--drivers/clocksource/timer-vt8500.c150
1 files changed, 150 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-vt8500.c b/drivers/clocksource/timer-vt8500.c
new file mode 100644
index 000000000..a469b1b5f
--- /dev/null
+++ b/drivers/clocksource/timer-vt8500.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * arch/arm/mach-vt8500/timer.c
+ *
+ * Copyright (C) 2012 Tony Prisk <linux@prisktech.co.nz>
+ * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
+ */
+
+/*
+ * This file is copied and modified from the original timer.c provided by
+ * Alexey Charkov. Minor changes have been made for Device Tree Support.
+ */
+
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/delay.h>
+
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define VT8500_TIMER_OFFSET 0x0100
+#define VT8500_TIMER_HZ 3000000
+#define TIMER_MATCH_VAL 0x0000
+#define TIMER_COUNT_VAL 0x0010
+#define TIMER_STATUS_VAL 0x0014
+#define TIMER_IER_VAL 0x001c /* interrupt enable */
+#define TIMER_CTRL_VAL 0x0020
+#define TIMER_AS_VAL 0x0024 /* access status */
+#define TIMER_COUNT_R_ACTIVE (1 << 5) /* not ready for read */
+#define TIMER_COUNT_W_ACTIVE (1 << 4) /* not ready for write */
+#define TIMER_MATCH_W_ACTIVE (1 << 0) /* not ready for write */
+
+#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
+
+#define MIN_OSCR_DELTA 16
+
+static void __iomem *regbase;
+
+static u64 vt8500_timer_read(struct clocksource *cs)
+{
+ int loops = msecs_to_loops(10);
+ writel(3, regbase + TIMER_CTRL_VAL);
+ while ((readl((regbase + TIMER_AS_VAL)) & TIMER_COUNT_R_ACTIVE)
+ && --loops)
+ cpu_relax();
+ return readl(regbase + TIMER_COUNT_VAL);
+}
+
+static struct clocksource clocksource = {
+ .name = "vt8500_timer",
+ .rating = 200,
+ .read = vt8500_timer_read,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int vt8500_timer_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ int loops = msecs_to_loops(10);
+ u64 alarm = clocksource.read(&clocksource) + cycles;
+ while ((readl(regbase + TIMER_AS_VAL) & TIMER_MATCH_W_ACTIVE)
+ && --loops)
+ cpu_relax();
+ writel((unsigned long)alarm, regbase + TIMER_MATCH_VAL);
+
+ if ((signed)(alarm - clocksource.read(&clocksource)) <= MIN_OSCR_DELTA)
+ return -ETIME;
+
+ writel(1, regbase + TIMER_IER_VAL);
+
+ return 0;
+}
+
+static int vt8500_shutdown(struct clock_event_device *evt)
+{
+ writel(readl(regbase + TIMER_CTRL_VAL) | 1, regbase + TIMER_CTRL_VAL);
+ writel(0, regbase + TIMER_IER_VAL);
+ return 0;
+}
+
+static struct clock_event_device clockevent = {
+ .name = "vt8500_timer",
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 200,
+ .set_next_event = vt8500_timer_set_next_event,
+ .set_state_shutdown = vt8500_shutdown,
+ .set_state_oneshot = vt8500_shutdown,
+};
+
+static irqreturn_t vt8500_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+ writel(0xf, regbase + TIMER_STATUS_VAL);
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static int __init vt8500_timer_init(struct device_node *np)
+{
+ int timer_irq, ret;
+
+ regbase = of_iomap(np, 0);
+ if (!regbase) {
+ pr_err("%s: Missing iobase description in Device Tree\n",
+ __func__);
+ return -ENXIO;
+ }
+
+ timer_irq = irq_of_parse_and_map(np, 0);
+ if (!timer_irq) {
+ pr_err("%s: Missing irq description in Device Tree\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ writel(1, regbase + TIMER_CTRL_VAL);
+ writel(0xf, regbase + TIMER_STATUS_VAL);
+ writel(~0, regbase + TIMER_MATCH_VAL);
+
+ ret = clocksource_register_hz(&clocksource, VT8500_TIMER_HZ);
+ if (ret) {
+ pr_err("%s: clocksource_register failed for %s\n",
+ __func__, clocksource.name);
+ return ret;
+ }
+
+ clockevent.cpumask = cpumask_of(0);
+
+ ret = request_irq(timer_irq, vt8500_timer_interrupt,
+ IRQF_TIMER | IRQF_IRQPOLL, "vt8500_timer",
+ &clockevent);
+ if (ret) {
+ pr_err("%s: setup_irq failed for %s\n", __func__,
+ clockevent.name);
+ return ret;
+ }
+
+ clockevents_config_and_register(&clockevent, VT8500_TIMER_HZ,
+ MIN_OSCR_DELTA * 2, 0xf0000000);
+
+ return 0;
+}
+
+TIMER_OF_DECLARE(vt8500, "via,vt8500-timer", vt8500_timer_init);