* ARM architected timer
-ARM Cortex-A7 and Cortex-A15 have a per-core architected timer, which
-provides per-cpu timers.
+ARM cores may have a per-core architected timer, which provides per-cpu timers.
The timer is attached to a GIC to deliver its per-processor interrupts.
** Timer node properties:
-- compatible : Should at least contain "arm,armv7-timer".
+- compatible : Should at least contain one of
+ "arm,armv7-timer"
+ "arm,armv8-timer"
- interrupts : Interrupt list for secure, non-secure, virtual and
hypervisor timers, in that order.
help
This option enables support for the ARM system coherency unit
-config ARM_ARCH_TIMER
+config HAVE_ARM_ARCH_TIMER
bool "Architected timer support"
depends on CPU_V7
+ select ARM_ARCH_TIMER
help
This option enables support for the ARM architected timer
#ifndef __ASMARM_ARCH_TIMER_H
#define __ASMARM_ARCH_TIMER_H
+#include <asm/barrier.h>
#include <asm/errno.h>
#include <linux/clocksource.h>
+#include <linux/init.h>
+#include <linux/types.h>
+
+#include <clocksource/arm_arch_timer.h>
#ifdef CONFIG_ARM_ARCH_TIMER
int arch_timer_of_register(void);
int arch_timer_sched_clock_init(void);
-struct timecounter *arch_timer_get_timecounter(void);
+
+/*
+ * 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)
+{
+ 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 inline u32 arch_timer_reg_read(const int access, const int reg)
+{
+ 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;
+ }
+ }
+
+ 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 inline u32 arch_timer_get_cntfrq(void)
+{
+ u32 val;
+ asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
+ return val;
+}
+
+static inline u64 arch_counter_get_cntpct(void)
+{
+ u64 cval;
+
+ isb();
+ asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (cval));
+ return cval;
+}
+
+static inline u64 arch_counter_get_cntvct(void)
+{
+ u64 cval;
+
+ isb();
+ asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (cval));
+ return cval;
+}
+
+static inline void __cpuinit arch_counter_set_user_access(void)
+{
+ u32 cntkctl;
+
+ asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl));
+
+ /* disable user access to everything */
+ cntkctl &= ~((3 << 8) | (7 << 0));
+
+ asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl));
+}
#else
static inline int arch_timer_of_register(void)
{
{
return -ENXIO;
}
-
-static inline struct timecounter *arch_timer_get_timecounter(void)
-{
- return NULL;
-}
#endif
#endif
* published by the Free Software Foundation.
*/
#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/delay.h>
-#include <linux/device.h>
-#include <linux/smp.h>
-#include <linux/cpu.h>
-#include <linux/jiffies.h>
-#include <linux/clockchips.h>
-#include <linux/interrupt.h>
-#include <linux/of_irq.h>
-#include <linux/io.h>
+#include <linux/types.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;
+#include <clocksource/arm_arch_timer.h>
-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;
-
-static bool arch_timer_use_virtual = true;
-
-/*
- * Architected system timer support.
- */
-
-#define ARCH_TIMER_CTRL_ENABLE (1 << 0)
-#define ARCH_TIMER_CTRL_IT_MASK (1 << 1)
-#define ARCH_TIMER_CTRL_IT_STAT (1 << 2)
-
-#define ARCH_TIMER_REG_CTRL 0
-#define ARCH_TIMER_REG_FREQ 1
-#define ARCH_TIMER_REG_TVAL 2
-
-#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)
-{
- 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 inline u32 arch_timer_reg_read(const int access, const int reg)
-{
- 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;
- }
- }
-
- 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 inline cycle_t arch_timer_counter_read(const int access)
-{
- 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);
-}
-
-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(access, ARCH_TIMER_REG_CTRL, ctrl);
- evt->event_handler(evt);
- return IRQ_HANDLED;
- }
-
- return IRQ_NONE;
-}
-
-static irqreturn_t arch_timer_handler_virt(int irq, void *dev_id)
-{
- struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
-
- return timer_handler(ARCH_TIMER_VIRT_ACCESS, evt);
-}
-
-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:
- 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 void arch_timer_set_mode_virt(enum clock_event_mode mode,
- struct clock_event_device *clk)
-{
- timer_set_mode(ARCH_TIMER_VIRT_ACCESS, mode);
-}
-
-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);
-}
-
-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)
-{
- 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;
- } 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;
-
- 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;
-}
-
-/* Is the optional system timer available? */
-static int local_timer_is_architected(void)
-{
- return (cpu_architecture() >= CPU_ARCH_ARMv7) &&
- ((read_cpuid_ext(CPUID_EXT_PFR1) >> 16) & 0xf) == 1;
-}
-
-static int arch_timer_available(void)
-{
- unsigned long freq;
-
- if (!local_timer_is_architected())
- return -ENXIO;
-
- if (arch_timer_rate == 0) {
- freq = arch_timer_reg_read(ARCH_TIMER_PHYS_ACCESS,
- ARCH_TIMER_REG_FREQ);
-
- /* Check the timer frequency. */
- if (freq == 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",
- arch_timer_rate / 1000000, (arch_timer_rate / 10000) % 100,
- arch_timer_use_virtual ? "virt" : "phys");
- return 0;
-}
-
-static u32 notrace arch_counter_get_cntpct32(void)
-{
- cycle_t cnt = arch_counter_get_cntpct();
-
- /*
- * 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 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)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();
-}
-
-static unsigned long arch_timer_read_current_timer(void)
+static unsigned long arch_timer_read_counter_long(void)
{
- return arch_counter_get_cntpct();
+ return arch_timer_read_counter();
}
-static cycle_t arch_counter_read_cc(const struct cyclecounter *cc)
+static u32 arch_timer_read_counter_u32(void)
{
- /*
- * Always use the physical counter for the clocksource.
- * CNTHCTL.PL1PCTEN must be set to 1.
- */
- return arch_counter_get_cntpct();
+ return arch_timer_read_counter();
}
-static struct clocksource clocksource_counter = {
- .name = "arch_sys_counter",
- .rating = 400,
- .read = arch_counter_read,
- .mask = CLOCKSOURCE_MASK(56),
- .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());
-
- 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 = {
- .setup = arch_timer_setup,
- .stop = arch_timer_stop,
-};
-
-static struct clock_event_device arch_timer_global_evt;
+static struct delay_timer arch_delay_timer;
-static int __init arch_timer_register(void)
+static void __init arch_timer_delay_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_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);
- }
- }
-
- if (err) {
- pr_err("arch_timer: can't register interrupt %d (%d)\n",
- ppi, err);
- goto out_free;
- }
-
- err = local_timer_register(&arch_timer_ops);
- if (err) {
- /*
- * We couldn't register as a local timer (could be
- * because we're on a UP platform, or because some
- * other local timer is already present...). Try as a
- * global timer instead.
- */
- arch_timer_global_evt.cpumask = cpumask_of(0);
- err = arch_timer_setup(&arch_timer_global_evt);
- }
- if (err)
- goto out_free_irq;
-
/* 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;
+ arch_delay_timer.read_current_timer = arch_timer_read_counter_long;
+ arch_delay_timer.freq = arch_timer_get_rate();
register_current_timer_delay(&arch_delay_timer);
- return 0;
-
-out_free_irq:
- 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;
}
-static const struct of_device_id arch_timer_of_match[] __initconst = {
- { .compatible = "arm,armv7-timer", },
- {},
-};
-
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) {
- pr_err("arch_timer: can't find DT node\n");
- return -ENODEV;
- }
-
- /* Try to determine the frequency from the device tree or CNTFRQ */
- if (!of_property_read_u32(np, "clock-frequency", &freq))
- arch_timer_rate = freq;
-
- for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
- arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
+ int ret;
- /*
- * 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;
+ ret = arch_timer_init();
+ if (ret)
+ return ret;
- 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;
- }
- }
+ arch_timer_delay_timer_register();
- return arch_timer_register();
+ return 0;
}
int __init arch_timer_sched_clock_init(void)
{
- u32 (*cnt32)(void);
- int err;
-
- err = arch_timer_available();
- if (err)
- return err;
-
- if (arch_timer_use_virtual)
- cnt32 = arch_counter_get_cntvct32;
- else
- cnt32 = arch_counter_get_cntpct32;
+ if (arch_timer_get_rate() == 0)
+ return -ENXIO;
- setup_sched_clock(cnt32, 32, arch_timer_rate);
+ setup_sched_clock(arch_timer_read_counter_u32,
+ 32, arch_timer_get_rate());
return 0;
}
config SOC_OMAP5
bool "TI OMAP5"
- select ARM_ARCH_TIMER
select ARM_CPU_SUSPEND if PM
select ARM_GIC
select CPU_V7
select HAVE_SMP
select COMMON_CLK
+ select HAVE_ARM_ARCH_TIMER
comment "OMAP Core Type"
depends on ARCH_OMAP2
select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
select ARM_AMBA
+ select ARM_ARCH_TIMER
select CLONE_BACKWARDS
select COMMON_CLK
select GENERIC_CLOCKEVENTS
--- /dev/null
+/*
+ * arch/arm64/include/asm/arch_timer.h
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_ARCH_TIMER_H
+#define __ASM_ARCH_TIMER_H
+
+#include <asm/barrier.h>
+
+#include <linux/init.h>
+#include <linux/types.h>
+
+#include <clocksource/arm_arch_timer.h>
+
+static inline void arch_timer_reg_write(int access, int reg, u32 val)
+{
+ if (access == ARCH_TIMER_PHYS_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("msr cntp_ctl_el0, %0" : : "r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("msr cntp_tval_el0, %0" : : "r" (val));
+ break;
+ default:
+ BUILD_BUG();
+ }
+ } else if (access == ARCH_TIMER_VIRT_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("msr cntv_ctl_el0, %0" : : "r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("msr cntv_tval_el0, %0" : : "r" (val));
+ break;
+ default:
+ BUILD_BUG();
+ }
+ } else {
+ BUILD_BUG();
+ }
+
+ isb();
+}
+
+static inline u32 arch_timer_reg_read(int access, int reg)
+{
+ u32 val;
+
+ if (access == ARCH_TIMER_PHYS_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("mrs %0, cntp_ctl_el0" : "=r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("mrs %0, cntp_tval_el0" : "=r" (val));
+ break;
+ default:
+ BUILD_BUG();
+ }
+ } else if (access == ARCH_TIMER_VIRT_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("mrs %0, cntv_ctl_el0" : "=r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("mrs %0, cntv_tval_el0" : "=r" (val));
+ break;
+ default:
+ BUILD_BUG();
+ }
+ } else {
+ BUILD_BUG();
+ }
+
+ return val;
+}
+
+static inline u32 arch_timer_get_cntfrq(void)
+{
+ u32 val;
+ asm volatile("mrs %0, cntfrq_el0" : "=r" (val));
+ return val;
+}
+
+static inline void __cpuinit arch_counter_set_user_access(void)
+{
+ u32 cntkctl;
+
+ /* Disable user access to the timers and the physical counter. */
+ asm volatile("mrs %0, cntkctl_el1" : "=r" (cntkctl));
+ cntkctl &= ~((3 << 8) | (1 << 0));
+
+ /* Enable user access to the virtual counter and frequency. */
+ cntkctl |= (1 << 1);
+ asm volatile("msr cntkctl_el1, %0" : : "r" (cntkctl));
+}
+
+static inline u64 arch_counter_get_cntpct(void)
+{
+ u64 cval;
+
+ isb();
+ asm volatile("mrs %0, cntpct_el0" : "=r" (cval));
+
+ return cval;
+}
+
+static inline u64 arch_counter_get_cntvct(void)
+{
+ u64 cval;
+
+ isb();
+ asm volatile("mrs %0, cntvct_el0" : "=r" (cval));
+
+ return cval;
+}
+
+#endif
+++ /dev/null
-/*
- * arch/arm64/include/asm/arm_generic.h
- *
- * Copyright (C) 2012 ARM Ltd.
- * Author: Marc Zyngier <marc.zyngier@arm.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-#ifndef __ASM_ARM_GENERIC_H
-#define __ASM_ARM_GENERIC_H
-
-#include <linux/clocksource.h>
-
-#define ARCH_TIMER_CTRL_ENABLE (1 << 0)
-#define ARCH_TIMER_CTRL_IMASK (1 << 1)
-#define ARCH_TIMER_CTRL_ISTATUS (1 << 2)
-
-#define ARCH_TIMER_REG_CTRL 0
-#define ARCH_TIMER_REG_FREQ 1
-#define ARCH_TIMER_REG_TVAL 2
-
-static inline void arch_timer_reg_write(int reg, u32 val)
-{
- switch (reg) {
- case ARCH_TIMER_REG_CTRL:
- asm volatile("msr cntp_ctl_el0, %0" : : "r" (val));
- break;
- case ARCH_TIMER_REG_TVAL:
- asm volatile("msr cntp_tval_el0, %0" : : "r" (val));
- break;
- default:
- BUILD_BUG();
- }
-
- isb();
-}
-
-static inline u32 arch_timer_reg_read(int reg)
-{
- u32 val;
-
- switch (reg) {
- case ARCH_TIMER_REG_CTRL:
- asm volatile("mrs %0, cntp_ctl_el0" : "=r" (val));
- break;
- case ARCH_TIMER_REG_FREQ:
- asm volatile("mrs %0, cntfrq_el0" : "=r" (val));
- break;
- case ARCH_TIMER_REG_TVAL:
- asm volatile("mrs %0, cntp_tval_el0" : "=r" (val));
- break;
- default:
- BUILD_BUG();
- }
-
- return val;
-}
-
-static inline void __cpuinit arch_counter_enable_user_access(void)
-{
- u32 cntkctl;
-
- /* Disable user access to the timers and the physical counter. */
- asm volatile("mrs %0, cntkctl_el1" : "=r" (cntkctl));
- cntkctl &= ~((3 << 8) | (1 << 0));
-
- /* Enable user access to the virtual counter and frequency. */
- cntkctl |= (1 << 1);
- asm volatile("msr cntkctl_el1, %0" : : "r" (cntkctl));
-}
-
-static inline cycle_t arch_counter_get_cntpct(void)
-{
- cycle_t cval;
-
- asm volatile("mrs %0, cntpct_el0" : "=r" (cval));
-
- return cval;
-}
-
-static inline cycle_t arch_counter_get_cntvct(void)
-{
- cycle_t cval;
-
- asm volatile("mrs %0, cntvct_el0" : "=r" (cval));
-
- return cval;
-}
-
-#endif
#include <linux/syscore_ops.h>
#include <linux/timer.h>
#include <linux/irq.h>
+#include <linux/delay.h>
-#include <clocksource/arm_generic.h>
+#include <clocksource/arm_arch_timer.h>
#include <asm/thread_info.h>
#include <asm/stacktrace.h>
EXPORT_SYMBOL(profile_pc);
#endif
+static u64 sched_clock_mult __read_mostly;
+
+unsigned long long notrace sched_clock(void)
+{
+ return arch_timer_read_counter() * sched_clock_mult;
+}
+
+int read_current_timer(unsigned long *timer_value)
+{
+ *timer_value = arch_timer_read_counter();
+ return 0;
+}
+
void __init time_init(void)
{
- arm_generic_timer_init();
+ u32 arch_timer_rate;
+
+ if (arch_timer_init())
+ panic("Unable to initialise architected timer.\n");
+
+ arch_timer_rate = arch_timer_get_rate();
+
+ /* Cache the sched_clock multiplier to save a divide in the hot path. */
+ sched_clock_mult = NSEC_PER_SEC / arch_timer_rate;
+
+ /* Calibrate the delay loop directly */
+ lpj_fine = arch_timer_rate / HZ;
}
help
Use the always on PRCMU Timer as sched_clock
-config CLKSRC_ARM_GENERIC
- def_bool y if ARM64
- help
- This option enables support for the ARM generic timer.
+config ARM_ARCH_TIMER
+ bool
obj-$(CONFIG_ARCH_BCM2835) += bcm2835_timer.o
obj-$(CONFIG_SUNXI_TIMER) += sunxi_timer.o
-obj-$(CONFIG_CLKSRC_ARM_GENERIC) += arm_generic.o
+obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o
--- /dev/null
+/*
+ * linux/drivers/clocksource/arm_arch_timer.c
+ *
+ * Copyright (C) 2011 ARM Ltd.
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/smp.h>
+#include <linux/cpu.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>
+#include <linux/io.h>
+
+#include <asm/arch_timer.h>
+#include <asm/virt.h>
+
+#include <clocksource/arm_arch_timer.h>
+
+static u32 arch_timer_rate;
+
+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 bool arch_timer_use_virtual = true;
+
+/*
+ * Architected system timer support.
+ */
+
+static inline irqreturn_t 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(access, ARCH_TIMER_REG_CTRL, ctrl);
+ evt->event_handler(evt);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+static irqreturn_t arch_timer_handler_virt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ return timer_handler(ARCH_TIMER_VIRT_ACCESS, evt);
+}
+
+static irqreturn_t arch_timer_handler_phys(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = 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:
+ 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 void arch_timer_set_mode_virt(enum clock_event_mode mode,
+ struct clock_event_device *clk)
+{
+ timer_set_mode(ARCH_TIMER_VIRT_ACCESS, mode);
+}
+
+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);
+}
+
+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)
+{
+ 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;
+ } 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->cpumask = cpumask_of(smp_processor_id());
+
+ clk->set_mode(CLOCK_EVT_MODE_SHUTDOWN, NULL);
+
+ clockevents_config_and_register(clk, arch_timer_rate,
+ 0xf, 0x7fffffff);
+
+ 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);
+ }
+
+ arch_counter_set_user_access();
+
+ return 0;
+}
+
+static int arch_timer_available(void)
+{
+ 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;
+ }
+
+ arch_timer_rate = freq;
+ }
+
+ pr_info_once("Architected local timer running at %lu.%02luMHz (%s).\n",
+ (unsigned long)arch_timer_rate / 1000000,
+ (unsigned long)(arch_timer_rate / 10000) % 100,
+ arch_timer_use_virtual ? "virt" : "phys");
+ return 0;
+}
+
+u32 arch_timer_get_rate(void)
+{
+ return arch_timer_rate;
+}
+
+/*
+ * Some external users of arch_timer_read_counter (e.g. sched_clock) may try to
+ * call it before it has been initialised. Rather than incur a performance
+ * penalty checking for initialisation, provide a default implementation that
+ * won't lead to time appearing to jump backwards.
+ */
+static u64 arch_timer_read_zero(void)
+{
+ return 0;
+}
+
+u64 (*arch_timer_read_counter)(void) = arch_timer_read_zero;
+
+static cycle_t arch_counter_read(struct clocksource *cs)
+{
+ return arch_timer_read_counter();
+}
+
+static cycle_t arch_counter_read_cc(const struct cyclecounter *cc)
+{
+ return arch_timer_read_counter();
+}
+
+static struct clocksource clocksource_counter = {
+ .name = "arch_sys_counter",
+ .rating = 400,
+ .read = arch_counter_read,
+ .mask = CLOCKSOURCE_MASK(56),
+ .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());
+
+ 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 int __cpuinit arch_timer_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ struct clock_event_device *evt = this_cpu_ptr(arch_timer_evt);
+
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_STARTING:
+ arch_timer_setup(evt);
+ break;
+ case CPU_DYING:
+ arch_timer_stop(evt);
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block arch_timer_cpu_nb __cpuinitdata = {
+ .notifier_call = arch_timer_cpu_notify,
+};
+
+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_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);
+ }
+ }
+
+ if (err) {
+ pr_err("arch_timer: can't register interrupt %d (%d)\n",
+ ppi, err);
+ goto out_free;
+ }
+
+ err = register_cpu_notifier(&arch_timer_cpu_nb);
+ if (err)
+ goto out_free_irq;
+
+ /* Immediately configure the timer on the boot CPU */
+ arch_timer_setup(this_cpu_ptr(arch_timer_evt));
+
+ return 0;
+
+out_free_irq:
+ 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;
+}
+
+static const struct of_device_id arch_timer_of_match[] __initconst = {
+ { .compatible = "arm,armv7-timer", },
+ { .compatible = "arm,armv8-timer", },
+ {},
+};
+
+int __init arch_timer_init(void)
+{
+ struct device_node *np;
+ u32 freq;
+ int i;
+
+ np = of_find_matching_node(NULL, arch_timer_of_match);
+ if (!np) {
+ pr_err("arch_timer: can't find DT node\n");
+ return -ENODEV;
+ }
+
+ /* Try to determine the frequency from the device tree or CNTFRQ */
+ if (!of_property_read_u32(np, "clock-frequency", &freq))
+ arch_timer_rate = freq;
+
+ 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);
+
+ /*
+ * If HYP mode is available, we know that the physical timer
+ * has been configured to be accessible from PL1. Use it, so
+ * that a guest can use the virtual timer instead.
+ *
+ * If no interrupt provided for virtual timer, we'll have to
+ * stick to the physical timer. It'd better be accessible...
+ */
+ if (is_hyp_mode_available() || !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;
+ }
+ }
+
+ if (arch_timer_use_virtual)
+ arch_timer_read_counter = arch_counter_get_cntvct;
+ else
+ arch_timer_read_counter = arch_counter_get_cntpct;
+
+ return arch_timer_register();
+}
+++ /dev/null
-/*
- * Generic timers support
- *
- * Copyright (C) 2012 ARM Ltd.
- * Author: Marc Zyngier <marc.zyngier@arm.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/delay.h>
-#include <linux/device.h>
-#include <linux/smp.h>
-#include <linux/cpu.h>
-#include <linux/jiffies.h>
-#include <linux/interrupt.h>
-#include <linux/clockchips.h>
-#include <linux/of_irq.h>
-#include <linux/io.h>
-
-#include <clocksource/arm_generic.h>
-
-#include <asm/arm_generic.h>
-
-static u32 arch_timer_rate;
-static u64 sched_clock_mult __read_mostly;
-static DEFINE_PER_CPU(struct clock_event_device, arch_timer_evt);
-static int arch_timer_ppi;
-
-static irqreturn_t arch_timer_handle_irq(int irq, void *dev_id)
-{
- struct clock_event_device *evt = dev_id;
- unsigned long ctrl;
-
- ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL);
- if (ctrl & ARCH_TIMER_CTRL_ISTATUS) {
- ctrl |= ARCH_TIMER_CTRL_IMASK;
- arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl);
- evt->event_handler(evt);
- return IRQ_HANDLED;
- }
-
- return IRQ_NONE;
-}
-
-static void arch_timer_stop(void)
-{
- unsigned long ctrl;
-
- ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL);
- ctrl &= ~ARCH_TIMER_CTRL_ENABLE;
- arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl);
-}
-
-static void arch_timer_set_mode(enum clock_event_mode mode,
- struct clock_event_device *clk)
-{
- switch (mode) {
- case CLOCK_EVT_MODE_UNUSED:
- case CLOCK_EVT_MODE_SHUTDOWN:
- arch_timer_stop();
- break;
- default:
- break;
- }
-}
-
-static int arch_timer_set_next_event(unsigned long evt,
- struct clock_event_device *unused)
-{
- unsigned long ctrl;
-
- ctrl = arch_timer_reg_read(ARCH_TIMER_REG_CTRL);
- ctrl |= ARCH_TIMER_CTRL_ENABLE;
- ctrl &= ~ARCH_TIMER_CTRL_IMASK;
-
- arch_timer_reg_write(ARCH_TIMER_REG_TVAL, evt);
- arch_timer_reg_write(ARCH_TIMER_REG_CTRL, ctrl);
-
- return 0;
-}
-
-static void __cpuinit arch_timer_setup(struct clock_event_device *clk)
-{
- /* Let's make sure the timer is off before doing anything else */
- arch_timer_stop();
-
- clk->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP;
- clk->name = "arch_sys_timer";
- clk->rating = 400;
- clk->set_mode = arch_timer_set_mode;
- clk->set_next_event = arch_timer_set_next_event;
- clk->irq = arch_timer_ppi;
- clk->cpumask = cpumask_of(smp_processor_id());
-
- clockevents_config_and_register(clk, arch_timer_rate,
- 0xf, 0x7fffffff);
-
- enable_percpu_irq(clk->irq, 0);
-
- /* Ensure the virtual counter is visible to userspace for the vDSO. */
- arch_counter_enable_user_access();
-}
-
-static void __init arch_timer_calibrate(void)
-{
- if (arch_timer_rate == 0) {
- arch_timer_reg_write(ARCH_TIMER_REG_CTRL, 0);
- arch_timer_rate = arch_timer_reg_read(ARCH_TIMER_REG_FREQ);
-
- /* Check the timer frequency. */
- if (arch_timer_rate == 0)
- panic("Architected timer frequency is set to zero.\n"
- "You must set this in your .dts file\n");
- }
-
- /* Cache the sched_clock multiplier to save a divide in the hot path. */
-
- sched_clock_mult = DIV_ROUND_CLOSEST(NSEC_PER_SEC, arch_timer_rate);
-
- pr_info("Architected local timer running at %u.%02uMHz.\n",
- arch_timer_rate / 1000000, (arch_timer_rate / 10000) % 100);
-}
-
-static cycle_t arch_counter_read(struct clocksource *cs)
-{
- return arch_counter_get_cntpct();
-}
-
-static struct clocksource clocksource_counter = {
- .name = "arch_sys_counter",
- .rating = 400,
- .read = arch_counter_read,
- .mask = CLOCKSOURCE_MASK(56),
- .flags = (CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_VALID_FOR_HRES),
-};
-
-int read_current_timer(unsigned long *timer_value)
-{
- *timer_value = arch_counter_get_cntpct();
- return 0;
-}
-
-unsigned long long notrace sched_clock(void)
-{
- return arch_counter_get_cntvct() * sched_clock_mult;
-}
-
-static int __cpuinit arch_timer_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu)
-{
- int cpu = (long)hcpu;
- struct clock_event_device *clk = per_cpu_ptr(&arch_timer_evt, cpu);
-
- switch(action) {
- case CPU_STARTING:
- case CPU_STARTING_FROZEN:
- arch_timer_setup(clk);
- break;
-
- case CPU_DYING:
- case CPU_DYING_FROZEN:
- pr_debug("arch_timer_teardown disable IRQ%d cpu #%d\n",
- clk->irq, cpu);
- disable_percpu_irq(clk->irq);
- arch_timer_set_mode(CLOCK_EVT_MODE_UNUSED, clk);
- break;
- }
-
- return NOTIFY_OK;
-}
-
-static struct notifier_block __cpuinitdata arch_timer_cpu_nb = {
- .notifier_call = arch_timer_cpu_notify,
-};
-
-static const struct of_device_id arch_timer_of_match[] __initconst = {
- { .compatible = "arm,armv8-timer" },
- {},
-};
-
-int __init arm_generic_timer_init(void)
-{
- struct device_node *np;
- int err;
- u32 freq;
-
- np = of_find_matching_node(NULL, arch_timer_of_match);
- if (!np) {
- pr_err("arch_timer: can't find DT node\n");
- return -ENODEV;
- }
-
- /* 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_timer_calibrate();
-
- arch_timer_ppi = irq_of_parse_and_map(np, 0);
- pr_info("arch_timer: found %s irq %d\n", np->name, arch_timer_ppi);
-
- err = request_percpu_irq(arch_timer_ppi, arch_timer_handle_irq,
- np->name, &arch_timer_evt);
- if (err) {
- pr_err("arch_timer: can't register interrupt %d (%d)\n",
- arch_timer_ppi, err);
- return err;
- }
-
- clocksource_register_hz(&clocksource_counter, arch_timer_rate);
-
- /* Calibrate the delay loop directly */
- lpj_fine = DIV_ROUND_CLOSEST(arch_timer_rate, HZ);
-
- /* Immediately configure the timer on the boot CPU */
- arch_timer_setup(this_cpu_ptr(&arch_timer_evt));
-
- register_cpu_notifier(&arch_timer_cpu_nb);
-
- return 0;
-}
--- /dev/null
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __CLKSOURCE_ARM_ARCH_TIMER_H
+#define __CLKSOURCE_ARM_ARCH_TIMER_H
+
+#include <linux/clocksource.h>
+#include <linux/types.h>
+
+#define ARCH_TIMER_CTRL_ENABLE (1 << 0)
+#define ARCH_TIMER_CTRL_IT_MASK (1 << 1)
+#define ARCH_TIMER_CTRL_IT_STAT (1 << 2)
+
+#define ARCH_TIMER_REG_CTRL 0
+#define ARCH_TIMER_REG_TVAL 1
+
+#define ARCH_TIMER_PHYS_ACCESS 0
+#define ARCH_TIMER_VIRT_ACCESS 1
+
+#ifdef CONFIG_ARM_ARCH_TIMER
+
+extern int arch_timer_init(void);
+extern u32 arch_timer_get_rate(void);
+extern u64 (*arch_timer_read_counter)(void);
+extern struct timecounter *arch_timer_get_timecounter(void);
+
+#else
+
+static inline int arch_timer_init(void)
+{
+ return -ENXIO;
+}
+
+static inline u32 arch_timer_get_rate(void)
+{
+ return 0;
+}
+
+static inline u64 arch_timer_read_counter(void)
+{
+ return 0;
+}
+
+static struct timecounter *arch_timer_get_timecounter(void)
+{
+ return NULL;
+}
+
+#endif
+
+#endif
+++ /dev/null
-/*
- * Copyright (C) 2012 ARM Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-#ifndef __CLKSOURCE_ARM_GENERIC_H
-#define __CLKSOURCE_ARM_GENERIC_H
-
-extern int arm_generic_timer_init(void);
-
-#endif
projects / firefly-linux-kernel-4.4.55.git / commitdiff