diff options
author | Mark Rutland <mark.rutland@arm.com> | 2012-11-12 14:33:44 +0000 |
---|---|---|
committer | Mark Rutland <mark.rutland@arm.com> | 2013-01-31 15:51:49 +0000 |
commit | 8a4da6e36c582ff746191eca85b6c1c068dbfbd6 (patch) | |
tree | 9c4be7e6853d33f35580e6f7c64c3d410dfe4aaf /arch | |
parent | b2deabe3ba664a1ec47400c0ca285e951874e0cc (diff) | |
download | linux-stable-8a4da6e36c582ff746191eca85b6c1c068dbfbd6.tar.gz linux-stable-8a4da6e36c582ff746191eca85b6c1c068dbfbd6.tar.bz2 linux-stable-8a4da6e36c582ff746191eca85b6c1c068dbfbd6.zip |
arm: arch_timer: move core to drivers/clocksource
The core functionality of the arch_timer driver is not directly tied to
anything under arch/arm, and can be split out.
This patch factors out the core of the arch_timer driver, so it can be
shared with other architectures. A couple of functions are added so
that architecture-specific code can interact with the driver without
needing to touch its internals.
The ARM_ARCH_TIMER config variable is moved out to
drivers/clocksource/Kconfig, existing uses in arch/arm are replaced with
HAVE_ARM_ARCH_TIMER, which selects it.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/arm/Kconfig | 3 | ||||
-rw-r--r-- | arch/arm/include/asm/arch_timer.h | 19 | ||||
-rw-r--r-- | arch/arm/kernel/arch_timer.c | 386 | ||||
-rw-r--r-- | arch/arm/mach-omap2/Kconfig | 2 |
4 files changed, 24 insertions, 386 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 67874b82a4ed..e1162f52f2b5 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1572,9 +1572,10 @@ config HAVE_ARM_SCU 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 diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h index 729f6d98df86..7ade91d8cc6f 100644 --- a/arch/arm/include/asm/arch_timer.h +++ b/arch/arm/include/asm/arch_timer.h @@ -4,22 +4,14 @@ #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); - -#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 /* * These register accessors are marked inline so the compiler can @@ -128,11 +120,6 @@ static inline int arch_timer_sched_clock_init(void) { return -ENXIO; } - -static inline struct timecounter *arch_timer_get_timecounter(void) -{ - return NULL; -} #endif #endif diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c index 94f503394c5c..36ebcf4b516f 100644 --- a/arch/arm/kernel/arch_timer.c +++ b/arch/arm/kernel/arch_timer.c @@ -9,402 +9,52 @@ * 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/delay.h> -#include <asm/arch_timer.h> #include <asm/sched_clock.h> -static u32 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. - */ - -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 = 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; -} - -/* - * 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 u32 arch_timer_read_counter32(void) -{ - return arch_timer_read_counter(); -} - -static cycle_t arch_counter_read(struct clocksource *cs) +static unsigned long arch_timer_read_counter_long(void) { return arch_timer_read_counter(); } -static unsigned long arch_timer_read_current_timer(void) +static u32 arch_timer_read_counter_u32(void) { 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 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 = 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)); - /* 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; - } + int ret; - /* Try to determine the frequency from the device tree or CNTFRQ */ - if (!of_property_read_u32(np, "clock-frequency", &freq)) - arch_timer_rate = freq; + ret = arch_timer_init(); + if (ret) + return ret; - for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++) - arch_timer_ppi[i] = irq_of_parse_and_map(np, i); + arch_timer_delay_timer_register(); - of_node_put(np); - - /* - * 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; - } - } - - 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(); + return 0; } int __init arch_timer_sched_clock_init(void) { - int err; - - err = arch_timer_available(); - if (err) - return err; + if (arch_timer_get_rate() == 0) + return -ENXIO; - setup_sched_clock(arch_timer_read_counter32, - 32, arch_timer_rate); + setup_sched_clock(arch_timer_read_counter_u32, + 32, arch_timer_get_rate()); return 0; } diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig index 41b581fd0213..9d7909e58980 100644 --- a/arch/arm/mach-omap2/Kconfig +++ b/arch/arm/mach-omap2/Kconfig @@ -76,12 +76,12 @@ config ARCH_OMAP4 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 |