diff --git a/Documentation/devicetree/bindings/arm/arch_timer.txt b/Documentation/devicetree/bindings/arm/arch_timer.txt index 52478c83d0cc..20746e5abe6f 100644 --- a/Documentation/devicetree/bindings/arm/arch_timer.txt +++ b/Documentation/devicetree/bindings/arm/arch_timer.txt @@ -1,13 +1,14 @@ * 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. diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 35b6756f055b..0ad2823bf8c2 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1573,9 +1573,10 @@ 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 d40229d9a1c9..7ade91d8cc6f 100644 --- a/arch/arm/include/asm/arch_timer.h +++ b/arch/arm/include/asm/arch_timer.h @@ -1,13 +1,115 @@ #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) { @@ -18,11 +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 c8ef20747ee7..36ebcf4b516f 100644 --- a/arch/arm/kernel/arch_timer.c +++ b/arch/arm/kernel/arch_timer.c @@ -9,516 +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/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 unsigned long arch_timer_read_counter_long(void) +{ + return arch_timer_read_counter(); +} -static int arch_timer_ppi[MAX_TIMER_PPI]; +static u32 arch_timer_read_counter_u32(void) +{ + return arch_timer_read_counter(); +} -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) +static void __init arch_timer_delay_timer_register(void) { - 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) -{ - 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 = { - .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 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 = 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; + int ret; - np = of_find_matching_node(NULL, arch_timer_of_match); - if (!np) { - pr_err("arch_timer: can't find DT node\n"); - return -ENODEV; - } + ret = arch_timer_init(); + if (ret) + return 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; + arch_timer_delay_timer_register(); - 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(); + return 0; } int __init arch_timer_sched_clock_init(void) { - u32 (*cnt32)(void); - int err; + if (arch_timer_get_rate() == 0) + return -ENXIO; - err = arch_timer_available(); - if (err) - return err; - - if (arch_timer_use_virtual) - cnt32 = arch_counter_get_cntvct32; - else - cnt32 = arch_counter_get_cntpct32; - - setup_sched_clock(cnt32, 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 diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index f8f362aafee9..2b6cef6ad17f 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -3,6 +3,7 @@ config ARM64 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 diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h new file mode 100644 index 000000000000..91e2a6a6fcd4 --- /dev/null +++ b/arch/arm64/include/asm/arch_timer.h @@ -0,0 +1,133 @@ +/* + * 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 diff --git a/arch/arm64/include/asm/arm_generic.h b/arch/arm64/include/asm/arm_generic.h deleted file mode 100644 index df2aeb82f74e..000000000000 --- a/arch/arm64/include/asm/arm_generic.h +++ /dev/null @@ -1,100 +0,0 @@ -/* - * 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 diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c index 3b4b7258f492..b0ef18d14c3b 100644 --- a/arch/arm64/kernel/time.c +++ b/arch/arm64/kernel/time.c @@ -31,8 +31,9 @@ #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> @@ -59,7 +60,31 @@ unsigned long profile_pc(struct pt_regs *regs) 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; } diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 7fdcbd3f4da5..64798424b6cb 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -54,7 +54,5 @@ config CLKSRC_DBX500_PRCMU_SCHED_CLOCK 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 diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index f93453d01673..e69511c4c66e 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -17,4 +17,4 @@ obj-$(CONFIG_ARMADA_370_XP_TIMER) += time-armada-370-xp.o obj-$(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 diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c new file mode 100644 index 000000000000..d7ad425ab9b3 --- /dev/null +++ b/drivers/clocksource/arm_arch_timer.c @@ -0,0 +1,391 @@ +/* + * 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(); +} diff --git a/drivers/clocksource/arm_generic.c b/drivers/clocksource/arm_generic.c deleted file mode 100644 index 8ae1a61523ff..000000000000 --- a/drivers/clocksource/arm_generic.c +++ /dev/null @@ -1,232 +0,0 @@ -/* - * 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; -} diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h new file mode 100644 index 000000000000..b61f9961b0cc --- /dev/null +++ b/include/clocksource/arm_arch_timer.h @@ -0,0 +1,63 @@ +/* + * 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 diff --git a/include/clocksource/arm_generic.h b/include/clocksource/arm_generic.h deleted file mode 100644 index 5b41b0d27f0f..000000000000 --- a/include/clocksource/arm_generic.h +++ /dev/null @@ -1,21 +0,0 @@ -/* - * 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