diff options
author | Mark Rutland <mark.rutland@arm.com> | 2012-11-20 10:06:00 (GMT) |
---|---|---|
committer | Mark Rutland <mark.rutland@arm.com> | 2013-01-31 15:51:59 (GMT) |
commit | 1aee5d7a8120cbe3eca9180ef9276d75a4f51dd2 (patch) | |
tree | ac02d4cdc545251cb9197456c7fbd41a64a4dbe0 | |
parent | 1dac0dd71cdda2bd7395dd47a6b617ed296d4901 (diff) | |
download | linux-fsl-qoriq-1aee5d7a8120cbe3eca9180ef9276d75a4f51dd2.tar.xz |
arm64: move from arm_generic to arm_arch_timer
The arch_timer driver supports a superset of the functionality of the
arm_generic driver, and is not tied to a particular arch.
This patch moves arm64 to use the arch_timer driver, gaining additional
functionality in doing so, and removes the (now unused) arm_generic
driver. Timer-related hooks specific to arm64 are moved into
arch/arm64/kernel/time.c.
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>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
-rw-r--r-- | arch/arm64/Kconfig | 1 | ||||
-rw-r--r-- | arch/arm64/include/asm/arch_timer.h | 133 | ||||
-rw-r--r-- | arch/arm64/include/asm/arm_generic.h | 102 | ||||
-rw-r--r-- | arch/arm64/kernel/time.c | 29 | ||||
-rw-r--r-- | drivers/clocksource/Kconfig | 5 | ||||
-rw-r--r-- | drivers/clocksource/Makefile | 1 | ||||
-rw-r--r-- | drivers/clocksource/arm_arch_timer.c | 1 | ||||
-rw-r--r-- | drivers/clocksource/arm_generic.c | 232 | ||||
-rw-r--r-- | include/clocksource/arm_generic.h | 21 |
9 files changed, 162 insertions, 363 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index f8f362a..2b6cef6 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 0000000..91e2a6a --- /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 6ece2f1..0000000 --- a/arch/arm64/include/asm/arm_generic.h +++ /dev/null @@ -1,102 +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; - - isb(); - asm volatile("mrs %0, cntpct_el0" : "=r" (cval)); - - return cval; -} - -static inline cycle_t arch_counter_get_cntvct(void) -{ - cycle_t cval; - - isb(); - 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 3b4b725..b0ef18d 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 dbb085a..6479842 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -54,10 +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 32f858c..e69511c 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -17,5 +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 index 3e4739d..ec30a73 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -338,6 +338,7 @@ out: static const struct of_device_id arch_timer_of_match[] __initconst = { { .compatible = "arm,armv7-timer", }, + { .compatible = "arm,armv8-timer", }, {}, }; diff --git a/drivers/clocksource/arm_generic.c b/drivers/clocksource/arm_generic.c deleted file mode 100644 index 8ae1a61..0000000 --- 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_generic.h b/include/clocksource/arm_generic.h deleted file mode 100644 index 5b41b0d..0000000 --- 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 |