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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-msc313e.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-msc313e.c')
-rw-r--r--drivers/clocksource/timer-msc313e.c253
1 files changed, 253 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-msc313e.c b/drivers/clocksource/timer-msc313e.c
new file mode 100644
index 000000000..e4b9e3f16
--- /dev/null
+++ b/drivers/clocksource/timer-msc313e.c
@@ -0,0 +1,253 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MStar timer driver
+ *
+ * Copyright (C) 2021 Daniel Palmer
+ * Copyright (C) 2021 Romain Perier
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/sched_clock.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#ifdef CONFIG_ARM
+#include <linux/delay.h>
+#endif
+
+#include "timer-of.h"
+
+#define TIMER_NAME "msc313e_timer"
+
+#define MSC313E_REG_CTRL 0x00
+#define MSC313E_REG_CTRL_TIMER_EN BIT(0)
+#define MSC313E_REG_CTRL_TIMER_TRIG BIT(1)
+#define MSC313E_REG_CTRL_TIMER_INT_EN BIT(8)
+#define MSC313E_REG_TIMER_MAX_LOW 0x08
+#define MSC313E_REG_TIMER_MAX_HIGH 0x0c
+#define MSC313E_REG_COUNTER_LOW 0x10
+#define MSC313E_REG_COUNTER_HIGH 0x14
+#define MSC313E_REG_TIMER_DIVIDE 0x18
+
+#define MSC313E_CLK_DIVIDER 9
+#define TIMER_SYNC_TICKS 3
+
+#ifdef CONFIG_ARM
+struct msc313e_delay {
+ void __iomem *base;
+ struct delay_timer delay;
+};
+static struct msc313e_delay msc313e_delay;
+#endif
+
+static void __iomem *msc313e_clksrc;
+
+static void msc313e_timer_stop(void __iomem *base)
+{
+ writew(0, base + MSC313E_REG_CTRL);
+}
+
+static void msc313e_timer_start(void __iomem *base, bool periodic)
+{
+ u16 reg;
+
+ reg = readw(base + MSC313E_REG_CTRL);
+ if (periodic)
+ reg |= MSC313E_REG_CTRL_TIMER_EN;
+ else
+ reg |= MSC313E_REG_CTRL_TIMER_TRIG;
+ writew(reg | MSC313E_REG_CTRL_TIMER_INT_EN, base + MSC313E_REG_CTRL);
+}
+
+static void msc313e_timer_setup(void __iomem *base, unsigned long delay)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ writew(delay >> 16, base + MSC313E_REG_TIMER_MAX_HIGH);
+ writew(delay & 0xffff, base + MSC313E_REG_TIMER_MAX_LOW);
+ local_irq_restore(flags);
+}
+
+static unsigned long msc313e_timer_current_value(void __iomem *base)
+{
+ unsigned long flags;
+ u16 l, h;
+
+ local_irq_save(flags);
+ l = readw(base + MSC313E_REG_COUNTER_LOW);
+ h = readw(base + MSC313E_REG_COUNTER_HIGH);
+ local_irq_restore(flags);
+
+ return (((u32)h) << 16 | l);
+}
+
+static int msc313e_timer_clkevt_shutdown(struct clock_event_device *evt)
+{
+ struct timer_of *timer = to_timer_of(evt);
+
+ msc313e_timer_stop(timer_of_base(timer));
+
+ return 0;
+}
+
+static int msc313e_timer_clkevt_set_oneshot(struct clock_event_device *evt)
+{
+ struct timer_of *timer = to_timer_of(evt);
+
+ msc313e_timer_stop(timer_of_base(timer));
+ msc313e_timer_start(timer_of_base(timer), false);
+
+ return 0;
+}
+
+static int msc313e_timer_clkevt_set_periodic(struct clock_event_device *evt)
+{
+ struct timer_of *timer = to_timer_of(evt);
+
+ msc313e_timer_stop(timer_of_base(timer));
+ msc313e_timer_setup(timer_of_base(timer), timer_of_period(timer));
+ msc313e_timer_start(timer_of_base(timer), true);
+
+ return 0;
+}
+
+static int msc313e_timer_clkevt_next_event(unsigned long evt, struct clock_event_device *clkevt)
+{
+ struct timer_of *timer = to_timer_of(clkevt);
+
+ msc313e_timer_stop(timer_of_base(timer));
+ msc313e_timer_setup(timer_of_base(timer), evt);
+ msc313e_timer_start(timer_of_base(timer), false);
+
+ return 0;
+}
+
+static irqreturn_t msc313e_timer_clkevt_irq(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static u64 msc313e_timer_clksrc_read(struct clocksource *cs)
+{
+ return msc313e_timer_current_value(msc313e_clksrc) & cs->mask;
+}
+
+#ifdef CONFIG_ARM
+static unsigned long msc313e_read_delay_timer_read(void)
+{
+ return msc313e_timer_current_value(msc313e_delay.base);
+}
+#endif
+
+static u64 msc313e_timer_sched_clock_read(void)
+{
+ return msc313e_timer_current_value(msc313e_clksrc);
+}
+
+static struct clock_event_device msc313e_clkevt = {
+ .name = TIMER_NAME,
+ .rating = 300,
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .set_state_shutdown = msc313e_timer_clkevt_shutdown,
+ .set_state_periodic = msc313e_timer_clkevt_set_periodic,
+ .set_state_oneshot = msc313e_timer_clkevt_set_oneshot,
+ .tick_resume = msc313e_timer_clkevt_shutdown,
+ .set_next_event = msc313e_timer_clkevt_next_event,
+};
+
+static int __init msc313e_clkevt_init(struct device_node *np)
+{
+ int ret;
+ struct timer_of *to;
+
+ to = kzalloc_obj(*to);
+ if (!to)
+ return -ENOMEM;
+
+ to->flags = TIMER_OF_IRQ | TIMER_OF_CLOCK | TIMER_OF_BASE;
+ to->of_irq.handler = msc313e_timer_clkevt_irq;
+ ret = timer_of_init(np, to);
+ if (ret)
+ return ret;
+
+ if (of_device_is_compatible(np, "sstar,ssd20xd-timer")) {
+ to->of_clk.rate = clk_get_rate(to->of_clk.clk) / MSC313E_CLK_DIVIDER;
+ to->of_clk.period = DIV_ROUND_UP(to->of_clk.rate, HZ);
+ writew(MSC313E_CLK_DIVIDER - 1, timer_of_base(to) + MSC313E_REG_TIMER_DIVIDE);
+ }
+
+ msc313e_clkevt.cpumask = cpu_possible_mask;
+ msc313e_clkevt.irq = to->of_irq.irq;
+ to->clkevt = msc313e_clkevt;
+
+ clockevents_config_and_register(&to->clkevt, timer_of_rate(to),
+ TIMER_SYNC_TICKS, 0xffffffff);
+ return 0;
+}
+
+static int __init msc313e_clksrc_init(struct device_node *np)
+{
+ struct timer_of to = { 0 };
+ int ret;
+ u16 reg;
+
+ to.flags = TIMER_OF_BASE | TIMER_OF_CLOCK;
+ ret = timer_of_init(np, &to);
+ if (ret)
+ return ret;
+
+ msc313e_clksrc = timer_of_base(&to);
+ reg = readw(msc313e_clksrc + MSC313E_REG_CTRL);
+ reg |= MSC313E_REG_CTRL_TIMER_EN;
+ writew(reg, msc313e_clksrc + MSC313E_REG_CTRL);
+
+#ifdef CONFIG_ARM
+ msc313e_delay.base = timer_of_base(&to);
+ msc313e_delay.delay.read_current_timer = msc313e_read_delay_timer_read;
+ msc313e_delay.delay.freq = timer_of_rate(&to);
+
+ register_current_timer_delay(&msc313e_delay.delay);
+#endif
+
+ sched_clock_register(msc313e_timer_sched_clock_read, 32, timer_of_rate(&to));
+ return clocksource_mmio_init(timer_of_base(&to), TIMER_NAME, timer_of_rate(&to), 300, 32,
+ msc313e_timer_clksrc_read);
+}
+
+static int __init msc313e_timer_init(struct device_node *np)
+{
+ int ret = 0;
+ static int num_called;
+
+ switch (num_called) {
+ case 0:
+ ret = msc313e_clksrc_init(np);
+ if (ret)
+ return ret;
+ break;
+
+ default:
+ ret = msc313e_clkevt_init(np);
+ if (ret)
+ return ret;
+ break;
+ }
+
+ num_called++;
+
+ return 0;
+}
+
+TIMER_OF_DECLARE(msc313, "mstar,msc313e-timer", msc313e_timer_init);
+TIMER_OF_DECLARE(ssd20xd, "sstar,ssd20xd-timer", msc313e_timer_init);