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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-07 21:20:57 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-07 21:20:57 +0900
commit0e51793e162ca432fc5f04178cf82b80a92c2659 (patch)
treecf7ffdb5064e2f7b6647a63e7323d1c4e99b7739 /arch/arm/kernel/arch_timer.c
parent5cad3598ea0cdb817681f74518d3213583a04f7a (diff)
parentb4874a3d298606c20118d1ead73235439bbc2823 (diff)
Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM updates from Russell King: "This is the first chunk of ARM updates for this merge window. Conflicts are expected in two files - asm/timex.h and mach-integrator/integrator_cp.c. Nothing particularly stands out more than anything else. Most of the growth is down to the opcodes stuff from Dave Martin, which is countered by Rob's patches to use more of the asm-generic headers on ARM." (A few more conflicts grew since then, but it all looked fairly trivial) * 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (44 commits) ARM: 7548/1: include linux/sched.h in syscall.h ARM: 7541/1: Add ARM ERRATA 775420 workaround ARM: ensure vm_struct has its phys_addr member filled in ARM: 7540/1: kexec: Check segment memory addresses ARM: 7539/1: kexec: scan for dtb magic in segments ARM: 7538/1: delay: add registration mechanism for delay timer sources ARM: 7536/1: smp: Formalize an IPI for wakeup ARM: 7525/1: ptrace: use updated syscall number for syscall auditing ARM: 7524/1: support syscall tracing ARM: 7519/1: integrator: convert platform devices to Device Tree ARM: 7518/1: integrator: convert AMBA devices to device tree ARM: 7517/1: integrator: initial device tree support ARM: 7516/1: plat-versatile: add DT support to FPGA IRQ ARM: 7515/1: integrator: check PL010 base address from resource ARM: 7514/1: integrator: call common init function from machine ARM: 7522/1: arch_timers: register a time/cycle counter ARM: 7523/1: arch_timers: enable the use of the virtual timer ARM: 7531/1: mark kernelmode mem{cpy,set} non-experimental ARM: 7520/1: Build dtb files in all target ARM: Fix build warning in arch/arm/mm/alignment.c ...
Diffstat (limited to 'arch/arm/kernel/arch_timer.c')
-rw-r--r--arch/arm/kernel/arch_timer.c383
1 files changed, 273 insertions, 110 deletions
diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c
index cf258807160..c8ef20747ee 100644
--- a/arch/arm/kernel/arch_timer.c
+++ b/arch/arm/kernel/arch_timer.c
@@ -21,18 +21,28 @@
#include <linux/io.h>
#include <asm/cputype.h>
+#include <asm/delay.h>
#include <asm/localtimer.h>
#include <asm/arch_timer.h>
#include <asm/system_info.h>
#include <asm/sched_clock.h>
static unsigned long arch_timer_rate;
-static int arch_timer_ppi;
-static int arch_timer_ppi2;
+
+enum ppi_nr {
+ PHYS_SECURE_PPI,
+ PHYS_NONSECURE_PPI,
+ VIRT_PPI,
+ HYP_PPI,
+ MAX_TIMER_PPI
+};
+
+static int arch_timer_ppi[MAX_TIMER_PPI];
static struct clock_event_device __percpu **arch_timer_evt;
+static struct delay_timer arch_delay_timer;
-extern void init_current_timer_delay(unsigned long freq);
+static bool arch_timer_use_virtual = true;
/*
* Architected system timer support.
@@ -46,50 +56,104 @@ extern void init_current_timer_delay(unsigned long freq);
#define ARCH_TIMER_REG_FREQ 1
#define ARCH_TIMER_REG_TVAL 2
-static void arch_timer_reg_write(int reg, u32 val)
+#define ARCH_TIMER_PHYS_ACCESS 0
+#define ARCH_TIMER_VIRT_ACCESS 1
+
+/*
+ * These register accessors are marked inline so the compiler can
+ * nicely work out which register we want, and chuck away the rest of
+ * the code. At least it does so with a recent GCC (4.6.3).
+ */
+static inline void arch_timer_reg_write(const int access, const int reg, u32 val)
{
- switch (reg) {
- case ARCH_TIMER_REG_CTRL:
- asm volatile("mcr p15, 0, %0, c14, c2, 1" : : "r" (val));
- break;
- case ARCH_TIMER_REG_TVAL:
- asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" (val));
- break;
+ if (access == ARCH_TIMER_PHYS_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("mcr p15, 0, %0, c14, c2, 1" : : "r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" (val));
+ break;
+ }
+ }
+
+ if (access == ARCH_TIMER_VIRT_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("mcr p15, 0, %0, c14, c3, 1" : : "r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("mcr p15, 0, %0, c14, c3, 0" : : "r" (val));
+ break;
+ }
}
isb();
}
-static u32 arch_timer_reg_read(int reg)
+static inline u32 arch_timer_reg_read(const int access, const int reg)
{
- u32 val;
+ u32 val = 0;
+
+ if (access == ARCH_TIMER_PHYS_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("mrc p15, 0, %0, c14, c2, 1" : "=r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
+ break;
+ case ARCH_TIMER_REG_FREQ:
+ asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
+ break;
+ }
+ }
- switch (reg) {
- case ARCH_TIMER_REG_CTRL:
- asm volatile("mrc p15, 0, %0, c14, c2, 1" : "=r" (val));
- break;
- case ARCH_TIMER_REG_FREQ:
- asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
- break;
- case ARCH_TIMER_REG_TVAL:
- asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
- break;
- default:
- BUG();
+ if (access == ARCH_TIMER_VIRT_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("mrc p15, 0, %0, c14, c3, 1" : "=r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("mrc p15, 0, %0, c14, c3, 0" : "=r" (val));
+ break;
+ }
}
return val;
}
-static irqreturn_t arch_timer_handler(int irq, void *dev_id)
+static inline cycle_t arch_timer_counter_read(const int access)
{
- struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
- unsigned long ctrl;
+ cycle_t cval = 0;
+
+ if (access == ARCH_TIMER_PHYS_ACCESS)
+ asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (cval));
+
+ if (access == ARCH_TIMER_VIRT_ACCESS)
+ asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (cval));
+
+ return cval;
+}
+
+static inline cycle_t arch_counter_get_cntpct(void)
+{
+ return arch_timer_counter_read(ARCH_TIMER_PHYS_ACCESS);
+}
- ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL);
+static inline cycle_t arch_counter_get_cntvct(void)
+{
+ return arch_timer_counter_read(ARCH_TIMER_VIRT_ACCESS);
+}
+
+static irqreturn_t inline timer_handler(const int access,
+ struct clock_event_device *evt)
+{
+ unsigned long ctrl;
+ ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
if (ctrl & ARCH_TIMER_CTRL_IT_STAT) {
ctrl |= ARCH_TIMER_CTRL_IT_MASK;
- arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl);
+ arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
evt->event_handler(evt);
return IRQ_HANDLED;
}
@@ -97,63 +161,100 @@ static irqreturn_t arch_timer_handler(int irq, void *dev_id)
return IRQ_NONE;
}
-static void arch_timer_disable(void)
+static irqreturn_t arch_timer_handler_virt(int irq, void *dev_id)
{
- unsigned long ctrl;
+ struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
- ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL);
- ctrl &= ~ARCH_TIMER_CTRL_ENABLE;
- arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl);
+ return timer_handler(ARCH_TIMER_VIRT_ACCESS, evt);
}
-static void arch_timer_set_mode(enum clock_event_mode mode,
- struct clock_event_device *clk)
+static irqreturn_t arch_timer_handler_phys(int irq, void *dev_id)
{
+ struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
+
+ return timer_handler(ARCH_TIMER_PHYS_ACCESS, evt);
+}
+
+static inline void timer_set_mode(const int access, int mode)
+{
+ unsigned long ctrl;
switch (mode) {
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
- arch_timer_disable();
+ ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
+ ctrl &= ~ARCH_TIMER_CTRL_ENABLE;
+ arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
break;
default:
break;
}
}
-static int arch_timer_set_next_event(unsigned long evt,
- struct clock_event_device *unused)
+static void arch_timer_set_mode_virt(enum clock_event_mode mode,
+ struct clock_event_device *clk)
{
- unsigned long ctrl;
+ timer_set_mode(ARCH_TIMER_VIRT_ACCESS, mode);
+}
- ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL);
+static void arch_timer_set_mode_phys(enum clock_event_mode mode,
+ struct clock_event_device *clk)
+{
+ timer_set_mode(ARCH_TIMER_PHYS_ACCESS, mode);
+}
+
+static inline void set_next_event(const int access, unsigned long evt)
+{
+ unsigned long ctrl;
+ ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
ctrl |= ARCH_TIMER_CTRL_ENABLE;
ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
+ arch_timer_reg_write(access, ARCH_TIMER_REG_TVAL, evt);
+ arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
+}
- arch_timer_reg_write(ARCH_TIMER_REG_TVAL, evt);
- arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl);
+static int arch_timer_set_next_event_virt(unsigned long evt,
+ struct clock_event_device *unused)
+{
+ set_next_event(ARCH_TIMER_VIRT_ACCESS, evt);
+ return 0;
+}
+static int arch_timer_set_next_event_phys(unsigned long evt,
+ struct clock_event_device *unused)
+{
+ set_next_event(ARCH_TIMER_PHYS_ACCESS, evt);
return 0;
}
static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
{
- /* Be safe... */
- arch_timer_disable();
-
clk->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP;
clk->name = "arch_sys_timer";
clk->rating = 450;
- clk->set_mode = arch_timer_set_mode;
- clk->set_next_event = arch_timer_set_next_event;
- clk->irq = arch_timer_ppi;
+ 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;
+ }
+
+ clk->set_mode(CLOCK_EVT_MODE_SHUTDOWN, NULL);
clockevents_config_and_register(clk, arch_timer_rate,
0xf, 0x7fffffff);
*__this_cpu_ptr(arch_timer_evt) = clk;
- enable_percpu_irq(clk->irq, 0);
- if (arch_timer_ppi2)
- enable_percpu_irq(arch_timer_ppi2, 0);
+ if (arch_timer_use_virtual)
+ enable_percpu_irq(arch_timer_ppi[VIRT_PPI], 0);
+ else {
+ enable_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI], 0);
+ if (arch_timer_ppi[PHYS_NONSECURE_PPI])
+ enable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI], 0);
+ }
return 0;
}
@@ -173,8 +274,8 @@ static int arch_timer_available(void)
return -ENXIO;
if (arch_timer_rate == 0) {
- arch_timer_reg_write(ARCH_TIMER_REG_CTRL, 0);
- freq = arch_timer_reg_read(ARCH_TIMER_REG_FREQ);
+ freq = arch_timer_reg_read(ARCH_TIMER_PHYS_ACCESS,
+ ARCH_TIMER_REG_FREQ);
/* Check the timer frequency. */
if (freq == 0) {
@@ -185,52 +286,57 @@ static int arch_timer_available(void)
arch_timer_rate = freq;
}
- pr_info_once("Architected local timer running at %lu.%02luMHz.\n",
- arch_timer_rate / 1000000, (arch_timer_rate / 10000) % 100);
+ pr_info_once("Architected local timer running at %lu.%02luMHz (%s).\n",
+ arch_timer_rate / 1000000, (arch_timer_rate / 10000) % 100,
+ arch_timer_use_virtual ? "virt" : "phys");
return 0;
}
-static inline cycle_t arch_counter_get_cntpct(void)
+static u32 notrace arch_counter_get_cntpct32(void)
{
- u32 cvall, cvalh;
-
- asm volatile("mrrc p15, 0, %0, %1, c14" : "=r" (cvall), "=r" (cvalh));
+ cycle_t cnt = arch_counter_get_cntpct();
- return ((cycle_t) cvalh << 32) | cvall;
-}
-
-static inline cycle_t arch_counter_get_cntvct(void)
-{
- u32 cvall, cvalh;
-
- asm volatile("mrrc p15, 1, %0, %1, c14" : "=r" (cvall), "=r" (cvalh));
-
- return ((cycle_t) cvalh << 32) | cvall;
+ /*
+ * The sched_clock infrastructure only knows about counters
+ * with at most 32bits. Forget about the upper 24 bits for the
+ * time being...
+ */
+ return (u32)cnt;
}
static u32 notrace arch_counter_get_cntvct32(void)
{
- cycle_t cntvct = arch_counter_get_cntvct();
+ cycle_t cnt = arch_counter_get_cntvct();
/*
* The sched_clock infrastructure only knows about counters
* with at most 32bits. Forget about the upper 24 bits for the
* time being...
*/
- return (u32)(cntvct & (u32)~0);
+ return (u32)cnt;
}
static cycle_t arch_counter_read(struct clocksource *cs)
{
+ /*
+ * Always use the physical counter for the clocksource.
+ * CNTHCTL.PL1PCTEN must be set to 1.
+ */
return arch_counter_get_cntpct();
}
-int read_current_timer(unsigned long *timer_val)
+static unsigned long arch_timer_read_current_timer(void)
{
- if (!arch_timer_rate)
- return -ENXIO;
- *timer_val = arch_counter_get_cntpct();
- return 0;
+ return arch_counter_get_cntpct();
+}
+
+static cycle_t arch_counter_read_cc(const struct cyclecounter *cc)
+{
+ /*
+ * Always use the physical counter for the clocksource.
+ * CNTHCTL.PL1PCTEN must be set to 1.
+ */
+ return arch_counter_get_cntpct();
}
static struct clocksource clocksource_counter = {
@@ -241,14 +347,32 @@ static struct clocksource clocksource_counter = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
+static struct cyclecounter cyclecounter = {
+ .read = arch_counter_read_cc,
+ .mask = CLOCKSOURCE_MASK(56),
+};
+
+static struct timecounter timecounter;
+
+struct timecounter *arch_timer_get_timecounter(void)
+{
+ return &timecounter;
+}
+
static void __cpuinit arch_timer_stop(struct clock_event_device *clk)
{
pr_debug("arch_timer_teardown disable IRQ%d cpu #%d\n",
clk->irq, smp_processor_id());
- disable_percpu_irq(clk->irq);
- if (arch_timer_ppi2)
- disable_percpu_irq(arch_timer_ppi2);
- arch_timer_set_mode(CLOCK_EVT_MODE_UNUSED, clk);
+
+ if (arch_timer_use_virtual)
+ disable_percpu_irq(arch_timer_ppi[VIRT_PPI]);
+ else {
+ disable_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI]);
+ if (arch_timer_ppi[PHYS_NONSECURE_PPI])
+ disable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI]);
+ }
+
+ clk->set_mode(CLOCK_EVT_MODE_UNUSED, clk);
}
static struct local_timer_ops arch_timer_ops __cpuinitdata = {
@@ -261,36 +385,48 @@ static struct clock_event_device arch_timer_global_evt;
static int __init arch_timer_register(void)
{
int err;
+ int ppi;
err = arch_timer_available();
if (err)
- return err;
+ goto out;
arch_timer_evt = alloc_percpu(struct clock_event_device *);
- if (!arch_timer_evt)
- return -ENOMEM;
+ 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_cntpct());
+
+ if (arch_timer_use_virtual) {
+ ppi = arch_timer_ppi[VIRT_PPI];
+ err = request_percpu_irq(ppi, arch_timer_handler_virt,
+ "arch_timer", arch_timer_evt);
+ } else {
+ ppi = arch_timer_ppi[PHYS_SECURE_PPI];
+ err = request_percpu_irq(ppi, arch_timer_handler_phys,
+ "arch_timer", arch_timer_evt);
+ if (!err && arch_timer_ppi[PHYS_NONSECURE_PPI]) {
+ ppi = arch_timer_ppi[PHYS_NONSECURE_PPI];
+ err = request_percpu_irq(ppi, arch_timer_handler_phys,
+ "arch_timer", arch_timer_evt);
+ if (err)
+ free_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI],
+ arch_timer_evt);
+ }
+ }
- err = request_percpu_irq(arch_timer_ppi, arch_timer_handler,
- "arch_timer", arch_timer_evt);
if (err) {
pr_err("arch_timer: can't register interrupt %d (%d)\n",
- arch_timer_ppi, err);
+ ppi, err);
goto out_free;
}
- if (arch_timer_ppi2) {
- err = request_percpu_irq(arch_timer_ppi2, arch_timer_handler,
- "arch_timer", arch_timer_evt);
- if (err) {
- pr_err("arch_timer: can't register interrupt %d (%d)\n",
- arch_timer_ppi2, err);
- arch_timer_ppi2 = 0;
- goto out_free_irq;
- }
- }
-
err = local_timer_register(&arch_timer_ops);
if (err) {
/*
@@ -302,21 +438,29 @@ static int __init arch_timer_register(void)
arch_timer_global_evt.cpumask = cpumask_of(0);
err = arch_timer_setup(&arch_timer_global_evt);
}
-
if (err)
goto out_free_irq;
- init_current_timer_delay(arch_timer_rate);
+ /* Use the architected timer for the delay loop. */
+ arch_delay_timer.read_current_timer = &arch_timer_read_current_timer;
+ arch_delay_timer.freq = arch_timer_rate;
+ register_current_timer_delay(&arch_delay_timer);
return 0;
out_free_irq:
- free_percpu_irq(arch_timer_ppi, arch_timer_evt);
- if (arch_timer_ppi2)
- free_percpu_irq(arch_timer_ppi2, arch_timer_evt);
+ if (arch_timer_use_virtual)
+ free_percpu_irq(arch_timer_ppi[VIRT_PPI], arch_timer_evt);
+ else {
+ free_percpu_irq(arch_timer_ppi[PHYS_SECURE_PPI],
+ arch_timer_evt);
+ if (arch_timer_ppi[PHYS_NONSECURE_PPI])
+ free_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI],
+ arch_timer_evt);
+ }
out_free:
free_percpu(arch_timer_evt);
-
+out:
return err;
}
@@ -329,6 +473,7 @@ int __init arch_timer_of_register(void)
{
struct device_node *np;
u32 freq;
+ int i;
np = of_find_matching_node(NULL, arch_timer_of_match);
if (!np) {
@@ -340,22 +485,40 @@ int __init arch_timer_of_register(void)
if (!of_property_read_u32(np, "clock-frequency", &freq))
arch_timer_rate = freq;
- arch_timer_ppi = irq_of_parse_and_map(np, 0);
- arch_timer_ppi2 = irq_of_parse_and_map(np, 1);
- pr_info("arch_timer: found %s irqs %d %d\n",
- np->name, arch_timer_ppi, arch_timer_ppi2);
+ for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
+ arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
+
+ /*
+ * If no interrupt provided for virtual timer, we'll have to
+ * stick to the physical timer. It'd better be accessible...
+ */
+ if (!arch_timer_ppi[VIRT_PPI]) {
+ arch_timer_use_virtual = false;
+
+ if (!arch_timer_ppi[PHYS_SECURE_PPI] ||
+ !arch_timer_ppi[PHYS_NONSECURE_PPI]) {
+ pr_warn("arch_timer: No interrupt available, giving up\n");
+ return -EINVAL;
+ }
+ }
return arch_timer_register();
}
int __init arch_timer_sched_clock_init(void)
{
+ u32 (*cnt32)(void);
int err;
err = arch_timer_available();
if (err)
return err;
- setup_sched_clock(arch_counter_get_cntvct32, 32, arch_timer_rate);
+ if (arch_timer_use_virtual)
+ cnt32 = arch_counter_get_cntvct32;
+ else
+ cnt32 = arch_counter_get_cntpct32;
+
+ setup_sched_clock(cnt32, 32, arch_timer_rate);
return 0;
}