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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/clocksource/timer-davinci.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/clocksource/timer-davinci.c')
-rw-r--r--drivers/clocksource/timer-davinci.c384
1 files changed, 384 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-davinci.c b/drivers/clocksource/timer-davinci.c
new file mode 100644
index 000000000..16ee0687e
--- /dev/null
+++ b/drivers/clocksource/timer-davinci.c
@@ -0,0 +1,384 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * TI DaVinci clocksource driver
+ *
+ * Copyright (C) 2019 Texas Instruments
+ * Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
+ * (with tiny parts adopted from code by Kevin Hilman <khilman@baylibre.com>)
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#include <clocksource/timer-davinci.h>
+
+#define DAVINCI_TIMER_REG_TIM12 0x10
+#define DAVINCI_TIMER_REG_TIM34 0x14
+#define DAVINCI_TIMER_REG_PRD12 0x18
+#define DAVINCI_TIMER_REG_PRD34 0x1c
+#define DAVINCI_TIMER_REG_TCR 0x20
+#define DAVINCI_TIMER_REG_TGCR 0x24
+
+#define DAVINCI_TIMER_TIMMODE_MASK GENMASK(3, 2)
+#define DAVINCI_TIMER_RESET_MASK GENMASK(1, 0)
+#define DAVINCI_TIMER_TIMMODE_32BIT_UNCHAINED BIT(2)
+#define DAVINCI_TIMER_UNRESET GENMASK(1, 0)
+
+#define DAVINCI_TIMER_ENAMODE_MASK GENMASK(1, 0)
+#define DAVINCI_TIMER_ENAMODE_DISABLED 0x00
+#define DAVINCI_TIMER_ENAMODE_ONESHOT BIT(0)
+#define DAVINCI_TIMER_ENAMODE_PERIODIC BIT(1)
+
+#define DAVINCI_TIMER_ENAMODE_SHIFT_TIM12 6
+#define DAVINCI_TIMER_ENAMODE_SHIFT_TIM34 22
+
+#define DAVINCI_TIMER_MIN_DELTA 0x01
+#define DAVINCI_TIMER_MAX_DELTA 0xfffffffe
+
+#define DAVINCI_TIMER_CLKSRC_BITS 32
+
+#define DAVINCI_TIMER_TGCR_DEFAULT \
+ (DAVINCI_TIMER_TIMMODE_32BIT_UNCHAINED | DAVINCI_TIMER_UNRESET)
+
+struct davinci_clockevent {
+ struct clock_event_device dev;
+ void __iomem *base;
+ unsigned int cmp_off;
+};
+
+/*
+ * This must be globally accessible by davinci_timer_read_sched_clock(), so
+ * let's keep it here.
+ */
+static struct {
+ struct clocksource dev;
+ void __iomem *base;
+ unsigned int tim_off;
+} davinci_clocksource;
+
+static struct davinci_clockevent *
+to_davinci_clockevent(struct clock_event_device *clockevent)
+{
+ return container_of(clockevent, struct davinci_clockevent, dev);
+}
+
+static unsigned int
+davinci_clockevent_read(struct davinci_clockevent *clockevent,
+ unsigned int reg)
+{
+ return readl_relaxed(clockevent->base + reg);
+}
+
+static void davinci_clockevent_write(struct davinci_clockevent *clockevent,
+ unsigned int reg, unsigned int val)
+{
+ writel_relaxed(val, clockevent->base + reg);
+}
+
+static void davinci_tim12_shutdown(void __iomem *base)
+{
+ unsigned int tcr;
+
+ tcr = DAVINCI_TIMER_ENAMODE_DISABLED <<
+ DAVINCI_TIMER_ENAMODE_SHIFT_TIM12;
+ /*
+ * This function is only ever called if we're using both timer
+ * halves. In this case TIM34 runs in periodic mode and we must
+ * not modify it.
+ */
+ tcr |= DAVINCI_TIMER_ENAMODE_PERIODIC <<
+ DAVINCI_TIMER_ENAMODE_SHIFT_TIM34;
+
+ writel_relaxed(tcr, base + DAVINCI_TIMER_REG_TCR);
+}
+
+static void davinci_tim12_set_oneshot(void __iomem *base)
+{
+ unsigned int tcr;
+
+ tcr = DAVINCI_TIMER_ENAMODE_ONESHOT <<
+ DAVINCI_TIMER_ENAMODE_SHIFT_TIM12;
+ /* Same as above. */
+ tcr |= DAVINCI_TIMER_ENAMODE_PERIODIC <<
+ DAVINCI_TIMER_ENAMODE_SHIFT_TIM34;
+
+ writel_relaxed(tcr, base + DAVINCI_TIMER_REG_TCR);
+}
+
+static int davinci_clockevent_shutdown(struct clock_event_device *dev)
+{
+ struct davinci_clockevent *clockevent;
+
+ clockevent = to_davinci_clockevent(dev);
+
+ davinci_tim12_shutdown(clockevent->base);
+
+ return 0;
+}
+
+static int davinci_clockevent_set_oneshot(struct clock_event_device *dev)
+{
+ struct davinci_clockevent *clockevent = to_davinci_clockevent(dev);
+
+ davinci_clockevent_write(clockevent, DAVINCI_TIMER_REG_TIM12, 0x0);
+
+ davinci_tim12_set_oneshot(clockevent->base);
+
+ return 0;
+}
+
+static int
+davinci_clockevent_set_next_event_std(unsigned long cycles,
+ struct clock_event_device *dev)
+{
+ struct davinci_clockevent *clockevent = to_davinci_clockevent(dev);
+
+ davinci_clockevent_shutdown(dev);
+
+ davinci_clockevent_write(clockevent, DAVINCI_TIMER_REG_TIM12, 0x0);
+ davinci_clockevent_write(clockevent, DAVINCI_TIMER_REG_PRD12, cycles);
+
+ davinci_clockevent_set_oneshot(dev);
+
+ return 0;
+}
+
+static int
+davinci_clockevent_set_next_event_cmp(unsigned long cycles,
+ struct clock_event_device *dev)
+{
+ struct davinci_clockevent *clockevent = to_davinci_clockevent(dev);
+ unsigned int curr_time;
+
+ curr_time = davinci_clockevent_read(clockevent,
+ DAVINCI_TIMER_REG_TIM12);
+ davinci_clockevent_write(clockevent,
+ clockevent->cmp_off, curr_time + cycles);
+
+ return 0;
+}
+
+static irqreturn_t davinci_timer_irq_timer(int irq, void *data)
+{
+ struct davinci_clockevent *clockevent = data;
+
+ if (!clockevent_state_oneshot(&clockevent->dev))
+ davinci_tim12_shutdown(clockevent->base);
+
+ clockevent->dev.event_handler(&clockevent->dev);
+
+ return IRQ_HANDLED;
+}
+
+static u64 notrace davinci_timer_read_sched_clock(void)
+{
+ return readl_relaxed(davinci_clocksource.base +
+ davinci_clocksource.tim_off);
+}
+
+static u64 davinci_clocksource_read(struct clocksource *dev)
+{
+ return davinci_timer_read_sched_clock();
+}
+
+/*
+ * Standard use-case: we're using tim12 for clockevent and tim34 for
+ * clocksource. The default is making the former run in oneshot mode
+ * and the latter in periodic mode.
+ */
+static void davinci_clocksource_init_tim34(void __iomem *base)
+{
+ int tcr;
+
+ tcr = DAVINCI_TIMER_ENAMODE_PERIODIC <<
+ DAVINCI_TIMER_ENAMODE_SHIFT_TIM34;
+ tcr |= DAVINCI_TIMER_ENAMODE_ONESHOT <<
+ DAVINCI_TIMER_ENAMODE_SHIFT_TIM12;
+
+ writel_relaxed(0x0, base + DAVINCI_TIMER_REG_TIM34);
+ writel_relaxed(UINT_MAX, base + DAVINCI_TIMER_REG_PRD34);
+ writel_relaxed(tcr, base + DAVINCI_TIMER_REG_TCR);
+}
+
+/*
+ * Special use-case on da830: the DSP may use tim34. We're using tim12 for
+ * both clocksource and clockevent. We set tim12 to periodic and don't touch
+ * tim34.
+ */
+static void davinci_clocksource_init_tim12(void __iomem *base)
+{
+ unsigned int tcr;
+
+ tcr = DAVINCI_TIMER_ENAMODE_PERIODIC <<
+ DAVINCI_TIMER_ENAMODE_SHIFT_TIM12;
+
+ writel_relaxed(0x0, base + DAVINCI_TIMER_REG_TIM12);
+ writel_relaxed(UINT_MAX, base + DAVINCI_TIMER_REG_PRD12);
+ writel_relaxed(tcr, base + DAVINCI_TIMER_REG_TCR);
+}
+
+static void davinci_timer_init(void __iomem *base)
+{
+ /* Set clock to internal mode and disable it. */
+ writel_relaxed(0x0, base + DAVINCI_TIMER_REG_TCR);
+ /*
+ * Reset both 32-bit timers, set no prescaler for timer 34, set the
+ * timer to dual 32-bit unchained mode, unreset both 32-bit timers.
+ */
+ writel_relaxed(DAVINCI_TIMER_TGCR_DEFAULT,
+ base + DAVINCI_TIMER_REG_TGCR);
+ /* Init both counters to zero. */
+ writel_relaxed(0x0, base + DAVINCI_TIMER_REG_TIM12);
+ writel_relaxed(0x0, base + DAVINCI_TIMER_REG_TIM34);
+}
+
+int __init davinci_timer_register(struct clk *clk,
+ const struct davinci_timer_cfg *timer_cfg)
+{
+ struct davinci_clockevent *clockevent;
+ unsigned int tick_rate;
+ void __iomem *base;
+ int rv;
+
+ rv = clk_prepare_enable(clk);
+ if (rv) {
+ pr_err("Unable to prepare and enable the timer clock\n");
+ return rv;
+ }
+
+ if (!request_mem_region(timer_cfg->reg.start,
+ resource_size(&timer_cfg->reg),
+ "davinci-timer")) {
+ pr_err("Unable to request memory region\n");
+ rv = -EBUSY;
+ goto exit_clk_disable;
+ }
+
+ base = ioremap(timer_cfg->reg.start, resource_size(&timer_cfg->reg));
+ if (!base) {
+ pr_err("Unable to map the register range\n");
+ rv = -ENOMEM;
+ goto exit_mem_region;
+ }
+
+ davinci_timer_init(base);
+ tick_rate = clk_get_rate(clk);
+
+ clockevent = kzalloc_obj(*clockevent);
+ if (!clockevent) {
+ rv = -ENOMEM;
+ goto exit_iounmap_base;
+ }
+
+ clockevent->dev.name = "tim12";
+ clockevent->dev.features = CLOCK_EVT_FEAT_ONESHOT;
+ clockevent->dev.cpumask = cpumask_of(0);
+ clockevent->base = base;
+
+ if (timer_cfg->cmp_off) {
+ clockevent->cmp_off = timer_cfg->cmp_off;
+ clockevent->dev.set_next_event =
+ davinci_clockevent_set_next_event_cmp;
+ } else {
+ clockevent->dev.set_next_event =
+ davinci_clockevent_set_next_event_std;
+ clockevent->dev.set_state_oneshot =
+ davinci_clockevent_set_oneshot;
+ clockevent->dev.set_state_shutdown =
+ davinci_clockevent_shutdown;
+ }
+
+ rv = request_irq(timer_cfg->irq[DAVINCI_TIMER_CLOCKEVENT_IRQ].start,
+ davinci_timer_irq_timer, IRQF_TIMER,
+ "clockevent/tim12", clockevent);
+ if (rv) {
+ pr_err("Unable to request the clockevent interrupt\n");
+ goto exit_free_clockevent;
+ }
+
+ davinci_clocksource.dev.rating = 300;
+ davinci_clocksource.dev.read = davinci_clocksource_read;
+ davinci_clocksource.dev.mask =
+ CLOCKSOURCE_MASK(DAVINCI_TIMER_CLKSRC_BITS);
+ davinci_clocksource.dev.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+ davinci_clocksource.base = base;
+
+ if (timer_cfg->cmp_off) {
+ davinci_clocksource.dev.name = "tim12";
+ davinci_clocksource.tim_off = DAVINCI_TIMER_REG_TIM12;
+ davinci_clocksource_init_tim12(base);
+ } else {
+ davinci_clocksource.dev.name = "tim34";
+ davinci_clocksource.tim_off = DAVINCI_TIMER_REG_TIM34;
+ davinci_clocksource_init_tim34(base);
+ }
+
+ clockevents_config_and_register(&clockevent->dev, tick_rate,
+ DAVINCI_TIMER_MIN_DELTA,
+ DAVINCI_TIMER_MAX_DELTA);
+
+ rv = clocksource_register_hz(&davinci_clocksource.dev, tick_rate);
+ if (rv) {
+ pr_err("Unable to register clocksource\n");
+ goto exit_free_irq;
+ }
+
+ sched_clock_register(davinci_timer_read_sched_clock,
+ DAVINCI_TIMER_CLKSRC_BITS, tick_rate);
+
+ return 0;
+
+exit_free_irq:
+ free_irq(timer_cfg->irq[DAVINCI_TIMER_CLOCKEVENT_IRQ].start,
+ clockevent);
+exit_free_clockevent:
+ kfree(clockevent);
+exit_iounmap_base:
+ iounmap(base);
+exit_mem_region:
+ release_mem_region(timer_cfg->reg.start,
+ resource_size(&timer_cfg->reg));
+exit_clk_disable:
+ clk_disable_unprepare(clk);
+ return rv;
+}
+
+static int __init of_davinci_timer_register(struct device_node *np)
+{
+ struct davinci_timer_cfg timer_cfg = { };
+ struct clk *clk;
+ int rv;
+
+ rv = of_address_to_resource(np, 0, &timer_cfg.reg);
+ if (rv) {
+ pr_err("Unable to get the register range for timer\n");
+ return rv;
+ }
+
+ rv = of_irq_to_resource_table(np, timer_cfg.irq,
+ DAVINCI_TIMER_NUM_IRQS);
+ if (rv != DAVINCI_TIMER_NUM_IRQS) {
+ pr_err("Unable to get the interrupts for timer\n");
+ return rv;
+ }
+
+ clk = of_clk_get(np, 0);
+ if (IS_ERR(clk)) {
+ pr_err("Unable to get the timer clock\n");
+ return PTR_ERR(clk);
+ }
+
+ rv = davinci_timer_register(clk, &timer_cfg);
+ if (rv)
+ clk_put(clk);
+
+ return rv;
+}
+TIMER_OF_DECLARE(davinci_timer, "ti,da830-timer", of_davinci_timer_register);