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path: root/drivers/clocksource/arm_arch_timer.c
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Diffstat (limited to 'drivers/clocksource/arm_arch_timer.c')
-rw-r--r--drivers/clocksource/arm_arch_timer.c402
1 files changed, 347 insertions, 55 deletions
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index a9ca28447b49..b3df46d9918b 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -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)
{
- arch_timer_reg_write_cp15(access, reg, val);
+ 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)
{
@@ -139,27 +240,62 @@ 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)
{
- clk->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP;
- clk->name = "arch_sys_timer";
- clk->rating = 450;
- if (arch_timer_use_virtual) {
- clk->irq = arch_timer_ppi[VIRT_PPI];
- clk->set_mode = arch_timer_set_mode_virt;
- clk->set_next_event = arch_timer_set_next_event_virt;
+ 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;
+
+ 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;
+ clk->set_next_event = arch_timer_set_next_event_virt;
+ } else {
+ clk->irq = arch_timer_ppi[PHYS_SECURE_PPI];
+ clk->set_mode = arch_timer_set_mode_phys;
+ clk->set_next_event = arch_timer_set_next_event_phys;
+ }
} else {
- clk->irq = arch_timer_ppi[PHYS_SECURE_PPI];
- clk->set_mode = arch_timer_set_mode_phys;
- clk->set_next_event = arch_timer_set_next_event_phys;
+ 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->cpumask = cpumask_of(smp_processor_id());
-
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;
-
- if (arch_timer_rate == 0) {
- freq = arch_timer_get_cntfrq();
-
- /* Check the timer frequency. */
- if (freq == 0) {
- pr_warn("Architected timer frequency not available\n");
- return -EINVAL;
- }
+ /* Who has more than one independent system counter? */
+ if (arch_timer_rate)
+ return;
- arch_timer_rate = freq;
+ /* 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();
}
- pr_info_once("Architected local timer running at %lu.%02luMHz (%s).\n",
+ /* Check the timer frequency. */
+ if (arch_timer_rate == 0)
+ pr_warn("Architected timer frequency not available\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);