clocksource: arch_timer: Add support for memory mapped timers (22006994) · Commits · 戴 / test

drivers/clocksource/arm_arch_timer.c

+347 −55

Original line number	Diff line number	Diff line
		@@ -16,13 +16,39 @@
		#include <linux/clockchips.h>
		#include <linux/interrupt.h>
		#include <linux/of_irq.h>
		#include <linux/of_address.h>
		#include <linux/io.h>
		#include <linux/slab.h>

		#include <asm/arch_timer.h>
		#include <asm/virt.h>

		#include <clocksource/arm_arch_timer.h>

		#define CNTTIDR 0x08
		#define CNTTIDR_VIRT(n) (BIT(1) << ((n) * 4))

		#define CNTVCT_LO 0x08
		#define CNTVCT_HI 0x0c
		#define CNTFRQ 0x10
		#define CNTP_TVAL 0x28
		#define CNTP_CTL 0x2c
		#define CNTV_TVAL 0x38
		#define CNTV_CTL 0x3c

		#define ARCH_CP15_TIMER BIT(0)
		#define ARCH_MEM_TIMER BIT(1)
		static unsigned arch_timers_present __initdata;

		static void __iomem *arch_counter_base;

		struct arch_timer {
		void __iomem *base;
		struct clock_event_device evt;
		};

		#define to_arch_timer(e) container_of(e, struct arch_timer, evt)

		static u32 arch_timer_rate;

		enum ppi_nr {
		@@ -38,6 +64,7 @@ static int arch_timer_ppi[MAX_TIMER_PPI];
		static struct clock_event_device __percpu *arch_timer_evt;

		static bool arch_timer_use_virtual = true;
		static bool arch_timer_mem_use_virtual;

		/*
		* Architected system timer support.
		@@ -47,14 +74,62 @@ static __always_inline
		void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val,
		struct clock_event_device *clk)
		{
		if (access == ARCH_TIMER_MEM_PHYS_ACCESS) {
		struct arch_timer *timer = to_arch_timer(clk);
		switch (reg) {
		case ARCH_TIMER_REG_CTRL:
		writel_relaxed(val, timer->base + CNTP_CTL);
		break;
		case ARCH_TIMER_REG_TVAL:
		writel_relaxed(val, timer->base + CNTP_TVAL);
		break;
		}
		} else if (access == ARCH_TIMER_MEM_VIRT_ACCESS) {
		struct arch_timer *timer = to_arch_timer(clk);
		switch (reg) {
		case ARCH_TIMER_REG_CTRL:
		writel_relaxed(val, timer->base + CNTV_CTL);
		break;
		case ARCH_TIMER_REG_TVAL:
		writel_relaxed(val, timer->base + CNTV_TVAL);
		break;
		}
		} else {
		arch_timer_reg_write_cp15(access, reg, val);
		}
		}

		static __always_inline
		u32 arch_timer_reg_read(int access, enum arch_timer_reg reg,
		struct clock_event_device *clk)
		{
		return arch_timer_reg_read_cp15(access, reg);
		u32 val;

		if (access == ARCH_TIMER_MEM_PHYS_ACCESS) {
		struct arch_timer *timer = to_arch_timer(clk);
		switch (reg) {
		case ARCH_TIMER_REG_CTRL:
		val = readl_relaxed(timer->base + CNTP_CTL);
		break;
		case ARCH_TIMER_REG_TVAL:
		val = readl_relaxed(timer->base + CNTP_TVAL);
		break;
		}
		} else if (access == ARCH_TIMER_MEM_VIRT_ACCESS) {
		struct arch_timer *timer = to_arch_timer(clk);
		switch (reg) {
		case ARCH_TIMER_REG_CTRL:
		val = readl_relaxed(timer->base + CNTV_CTL);
		break;
		case ARCH_TIMER_REG_TVAL:
		val = readl_relaxed(timer->base + CNTV_TVAL);
		break;
		}
		} else {
		val = arch_timer_reg_read_cp15(access, reg);
		}

		return val;
		}

		static __always_inline irqreturn_t timer_handler(const int access,
		@@ -86,6 +161,20 @@ static irqreturn_t arch_timer_handler_phys(int irq, void *dev_id)
		return timer_handler(ARCH_TIMER_PHYS_ACCESS, evt);
		}

		static irqreturn_t arch_timer_handler_phys_mem(int irq, void *dev_id)
		{
		struct clock_event_device *evt = dev_id;

		return timer_handler(ARCH_TIMER_MEM_PHYS_ACCESS, evt);
		}

		static irqreturn_t arch_timer_handler_virt_mem(int irq, void *dev_id)
		{
		struct clock_event_device *evt = dev_id;

		return timer_handler(ARCH_TIMER_MEM_VIRT_ACCESS, evt);
		}

		static __always_inline void timer_set_mode(const int access, int mode,
		struct clock_event_device *clk)
		{
		@@ -114,6 +203,18 @@ static void arch_timer_set_mode_phys(enum clock_event_mode mode,
		timer_set_mode(ARCH_TIMER_PHYS_ACCESS, mode, clk);
		}

		static void arch_timer_set_mode_virt_mem(enum clock_event_mode mode,
		struct clock_event_device *clk)
		{
		timer_set_mode(ARCH_TIMER_MEM_VIRT_ACCESS, mode, clk);
		}

		static void arch_timer_set_mode_phys_mem(enum clock_event_mode mode,
		struct clock_event_device *clk)
		{
		timer_set_mode(ARCH_TIMER_MEM_PHYS_ACCESS, mode, clk);
		}

		static __always_inline void set_next_event(const int access, unsigned long evt,
		struct clock_event_device *clk)
		{
		@@ -139,11 +240,30 @@ static int arch_timer_set_next_event_phys(unsigned long evt,
		return 0;
		}

		static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
		static int arch_timer_set_next_event_virt_mem(unsigned long evt,
		struct clock_event_device *clk)
		{
		set_next_event(ARCH_TIMER_MEM_VIRT_ACCESS, evt, clk);
		return 0;
		}

		static int arch_timer_set_next_event_phys_mem(unsigned long evt,
		struct clock_event_device *clk)
		{
		set_next_event(ARCH_TIMER_MEM_PHYS_ACCESS, evt, clk);
		return 0;
		}

		static void __cpuinit __arch_timer_setup(unsigned type,
		struct clock_event_device *clk)
		{
		clk->features = CLOCK_EVT_FEAT_ONESHOT \| CLOCK_EVT_FEAT_C3STOP;
		clk->features = CLOCK_EVT_FEAT_ONESHOT;

		if (type == ARCH_CP15_TIMER) {
		clk->features \|= CLOCK_EVT_FEAT_C3STOP;
		clk->name = "arch_sys_timer";
		clk->rating = 450;
		clk->cpumask = cpumask_of(smp_processor_id());
		if (arch_timer_use_virtual) {
		clk->irq = arch_timer_ppi[VIRT_PPI];
		clk->set_mode = arch_timer_set_mode_virt;
		@@ -153,13 +273,29 @@ static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
		clk->set_mode = arch_timer_set_mode_phys;
		clk->set_next_event = arch_timer_set_next_event_phys;
		}

		clk->cpumask = cpumask_of(smp_processor_id());
		} else {
		clk->name = "arch_mem_timer";
		clk->rating = 400;
		clk->cpumask = cpu_all_mask;
		if (arch_timer_mem_use_virtual) {
		clk->set_mode = arch_timer_set_mode_virt_mem;
		clk->set_next_event =
		arch_timer_set_next_event_virt_mem;
		} else {
		clk->set_mode = arch_timer_set_mode_phys_mem;
		clk->set_next_event =
		arch_timer_set_next_event_phys_mem;
		}
		}

		clk->set_mode(CLOCK_EVT_MODE_SHUTDOWN, clk);

		clockevents_config_and_register(clk, arch_timer_rate,
		0xf, 0x7fffffff);
		clockevents_config_and_register(clk, arch_timer_rate, 0xf, 0x7fffffff);
		}

		static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
		{
		__arch_timer_setup(ARCH_CP15_TIMER, clk);

		if (arch_timer_use_virtual)
		enable_percpu_irq(arch_timer_ppi[VIRT_PPI], 0);
		@@ -174,27 +310,41 @@ static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
		return 0;
		}

		static int arch_timer_available(void)
		static void
		arch_timer_detect_rate(void __iomem cntbase, struct device_node np)
		{
		u32 freq;
		/* Who has more than one independent system counter? */
		if (arch_timer_rate)
		return;

		if (arch_timer_rate == 0) {
		freq = arch_timer_get_cntfrq();
		/* Try to determine the frequency from the device tree or CNTFRQ */
		if (of_property_read_u32(np, "clock-frequency", &arch_timer_rate)) {
		if (cntbase)
		arch_timer_rate = readl_relaxed(cntbase + CNTFRQ);
		else
		arch_timer_rate = arch_timer_get_cntfrq();
		}

		/* Check the timer frequency. */
		if (freq == 0) {
		if (arch_timer_rate == 0)
		pr_warn("Architected timer frequency not available\n");
		return -EINVAL;
		}

		arch_timer_rate = freq;
		}

		pr_info_once("Architected local timer running at %lu.%02luMHz (%s).\n",
		static void arch_timer_banner(unsigned type)
		{
		pr_info("Architected %s%s%s timer(s) running at %lu.%02luMHz (%s%s%s).\n",
		type & ARCH_CP15_TIMER ? "cp15" : "",
		type == (ARCH_CP15_TIMER \| ARCH_MEM_TIMER) ? " and " : "",
		type & ARCH_MEM_TIMER ? "mmio" : "",
		(unsigned long)arch_timer_rate / 1000000,
		(unsigned long)(arch_timer_rate / 10000) % 100,
		arch_timer_use_virtual ? "virt" : "phys");
		return 0;
		type & ARCH_CP15_TIMER ?
		arch_timer_use_virtual ? "virt" : "phys" :
		"",
		type == (ARCH_CP15_TIMER \| ARCH_MEM_TIMER) ? "/" : "",
		type & ARCH_MEM_TIMER ?
		arch_timer_mem_use_virtual ? "virt" : "phys" :
		"");
		}

		u32 arch_timer_get_rate(void)
		@@ -202,19 +352,35 @@ u32 arch_timer_get_rate(void)
		return arch_timer_rate;
		}

		u64 arch_timer_read_counter(void)
		static u64 arch_counter_get_cntvct_mem(void)
		{
		return arch_counter_get_cntvct();
		u32 vct_lo, vct_hi, tmp_hi;

		do {
		vct_hi = readl_relaxed(arch_counter_base + CNTVCT_HI);
		vct_lo = readl_relaxed(arch_counter_base + CNTVCT_LO);
		tmp_hi = readl_relaxed(arch_counter_base + CNTVCT_HI);
		} while (vct_hi != tmp_hi);

		return ((u64) vct_hi << 32) \| vct_lo;
		}

		/*
		* Default to cp15 based access because arm64 uses this function for
		* sched_clock() before DT is probed and the cp15 method is guaranteed
		* to exist on arm64. arm doesn't use this before DT is probed so even
		* if we don't have the cp15 accessors we won't have a problem.
		*/
		u64 (*arch_timer_read_counter)(void) = arch_counter_get_cntvct;

		static cycle_t arch_counter_read(struct clocksource *cs)
		{
		return arch_counter_get_cntvct();
		return arch_timer_read_counter();
		}

		static cycle_t arch_counter_read_cc(const struct cyclecounter *cc)
		{
		return arch_counter_get_cntvct();
		return arch_timer_read_counter();
		}

		static struct clocksource clocksource_counter = {
		@@ -237,6 +403,23 @@ struct timecounter *arch_timer_get_timecounter(void)
		return &timecounter;
		}

		static void __init arch_counter_register(unsigned type)
		{
		u64 start_count;

		/* Register the CP15 based counter if we have one */
		if (type & ARCH_CP15_TIMER)
		arch_timer_read_counter = arch_counter_get_cntvct;
		else
		arch_timer_read_counter = arch_counter_get_cntvct_mem;

		start_count = arch_timer_read_counter();
		clocksource_register_hz(&clocksource_counter, arch_timer_rate);
		cyclecounter.mult = clocksource_counter.mult;
		cyclecounter.shift = clocksource_counter.shift;
		timecounter_init(&timecounter, &cyclecounter, start_count);
		}

		static void __cpuinit arch_timer_stop(struct clock_event_device *clk)
		{
		pr_debug("arch_timer_teardown disable IRQ%d cpu #%d\n",
		@@ -281,22 +464,12 @@ static int __init arch_timer_register(void)
		int err;
		int ppi;

		err = arch_timer_available();
		if (err)
		goto out;

		arch_timer_evt = alloc_percpu(struct clock_event_device);
		if (!arch_timer_evt) {
		err = -ENOMEM;
		goto out;
		}

		clocksource_register_hz(&clocksource_counter, arch_timer_rate);
		cyclecounter.mult = clocksource_counter.mult;
		cyclecounter.shift = clocksource_counter.shift;
		timecounter_init(&timecounter, &cyclecounter,
		arch_counter_get_cntvct());

		if (arch_timer_use_virtual) {
		ppi = arch_timer_ppi[VIRT_PPI];
		err = request_percpu_irq(ppi, arch_timer_handler_virt,
		@@ -347,24 +520,77 @@ out:
		return err;
		}

		static int __init arch_timer_mem_register(void __iomem *base, unsigned int irq)
		{
		int ret;
		irq_handler_t func;
		struct arch_timer *t;

		t = kzalloc(sizeof(*t), GFP_KERNEL);
		if (!t)
		return -ENOMEM;

		t->base = base;
		t->evt.irq = irq;
		__arch_timer_setup(ARCH_MEM_TIMER, &t->evt);

		if (arch_timer_mem_use_virtual)
		func = arch_timer_handler_virt_mem;
		else
		func = arch_timer_handler_phys_mem;

		ret = request_irq(irq, func, IRQF_TIMER, "arch_mem_timer", &t->evt);
		if (ret) {
		pr_err("arch_timer: Failed to request mem timer irq\n");
		kfree(t);
		}

		return ret;
		}

		static const struct of_device_id arch_timer_of_match[] __initconst = {
		{ .compatible = "arm,armv7-timer", },
		{ .compatible = "arm,armv8-timer", },
		{},
		};

		static const struct of_device_id arch_timer_mem_of_match[] __initconst = {
		{ .compatible = "arm,armv7-timer-mem", },
		{},
		};

		static void __init arch_timer_common_init(void)
		{
		unsigned mask = ARCH_CP15_TIMER \| ARCH_MEM_TIMER;

		/* Wait until both nodes are probed if we have two timers */
		if ((arch_timers_present & mask) != mask) {
		if (of_find_matching_node(NULL, arch_timer_mem_of_match) &&
		!(arch_timers_present & ARCH_MEM_TIMER))
		return;
		if (of_find_matching_node(NULL, arch_timer_of_match) &&
		!(arch_timers_present & ARCH_CP15_TIMER))
		return;
		}

		arch_timer_banner(arch_timers_present);
		arch_counter_register(arch_timers_present);
		arch_timer_arch_init();
		}

		static void __init arch_timer_init(struct device_node *np)
		{
		u32 freq;
		int i;

		if (arch_timer_get_rate()) {
		if (arch_timers_present & ARCH_CP15_TIMER) {
		pr_warn("arch_timer: multiple nodes in dt, skipping\n");
		return;
		}

		/* Try to determine the frequency from the device tree or CNTFRQ */
		if (!of_property_read_u32(np, "clock-frequency", &freq))
		arch_timer_rate = freq;

		arch_timers_present \|= ARCH_CP15_TIMER;
		for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);

		of_node_put(np);
		arch_timer_detect_rate(NULL, np);

		/*
		* If HYP mode is available, we know that the physical timer
		@@ -385,7 +611,73 @@ static void __init arch_timer_init(struct device_node *np)
		}

		arch_timer_register();
		arch_timer_arch_init();
		arch_timer_common_init();
		}
		CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_init);
		CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_init);

		static void __init arch_timer_mem_init(struct device_node *np)
		{
		struct device_node frame, best_frame = NULL;
		void __iomem cntctlbase, base;
		unsigned int irq;
		u32 cnttidr;

		arch_timers_present \|= ARCH_MEM_TIMER;
		cntctlbase = of_iomap(np, 0);
		if (!cntctlbase) {
		pr_err("arch_timer: Can't find CNTCTLBase\n");
		return;
		}

		cnttidr = readl_relaxed(cntctlbase + CNTTIDR);
		iounmap(cntctlbase);

		/*
		* Try to find a virtual capable frame. Otherwise fall back to a
		* physical capable frame.
		*/
		for_each_available_child_of_node(np, frame) {
		int n;

		if (of_property_read_u32(frame, "frame-number", &n)) {
		pr_err("arch_timer: Missing frame-number\n");
		of_node_put(best_frame);
		of_node_put(frame);
		return;
		}

		if (cnttidr & CNTTIDR_VIRT(n)) {
		of_node_put(best_frame);
		best_frame = frame;
		arch_timer_mem_use_virtual = true;
		break;
		}
		of_node_put(best_frame);
		best_frame = of_node_get(frame);
		}

		base = arch_counter_base = of_iomap(best_frame, 0);
		if (!base) {
		pr_err("arch_timer: Can't map frame's registers\n");
		of_node_put(best_frame);
		return;
		}

		if (arch_timer_mem_use_virtual)
		irq = irq_of_parse_and_map(best_frame, 1);
		else
		irq = irq_of_parse_and_map(best_frame, 0);
		of_node_put(best_frame);
		if (!irq) {
		pr_err("arch_timer: Frame missing %s irq",
		arch_timer_mem_use_virtual ? "virt" : "phys");
		return;
		}

		arch_timer_detect_rate(base, np);
		arch_timer_mem_register(base, irq);
		arch_timer_common_init();
		}
		CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
		arch_timer_mem_init);

include/clocksource/arm_arch_timer.h

+3 −1

Original line number	Diff line number	Diff line
		@@ -30,11 +30,13 @@ enum arch_timer_reg {

		#define ARCH_TIMER_PHYS_ACCESS 0
		#define ARCH_TIMER_VIRT_ACCESS 1
		#define ARCH_TIMER_MEM_PHYS_ACCESS 2
		#define ARCH_TIMER_MEM_VIRT_ACCESS 3

		#ifdef CONFIG_ARM_ARCH_TIMER

		extern u32 arch_timer_get_rate(void);
		extern u64 arch_timer_read_counter(void);
		extern u64 (*arch_timer_read_counter)(void);
		extern struct timecounter *arch_timer_get_timecounter(void);

		#else

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