diff options
Diffstat (limited to 'drivers/clocksource/arm_arch_timer.c')
| -rw-r--r-- | drivers/clocksource/arm_arch_timer.c | 139 |
1 files changed, 129 insertions, 10 deletions
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 28bce3f4f81d..73c487da6d2a 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -8,6 +8,9 @@ * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ + +#define pr_fmt(fmt) "arm_arch_timer: " fmt + #include <linux/init.h> #include <linux/kernel.h> #include <linux/device.h> @@ -91,6 +94,43 @@ early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg); * Architected system timer support. */ +#ifdef CONFIG_FSL_ERRATUM_A008585 +DEFINE_STATIC_KEY_FALSE(arch_timer_read_ool_enabled); +EXPORT_SYMBOL_GPL(arch_timer_read_ool_enabled); + +static int fsl_a008585_enable = -1; + +static int __init early_fsl_a008585_cfg(char *buf) +{ + int ret; + bool val; + + ret = strtobool(buf, &val); + if (ret) + return ret; + + fsl_a008585_enable = val; + return 0; +} +early_param("clocksource.arm_arch_timer.fsl-a008585", early_fsl_a008585_cfg); + +u32 __fsl_a008585_read_cntp_tval_el0(void) +{ + return __fsl_a008585_read_reg(cntp_tval_el0); +} + +u32 __fsl_a008585_read_cntv_tval_el0(void) +{ + return __fsl_a008585_read_reg(cntv_tval_el0); +} + +u64 __fsl_a008585_read_cntvct_el0(void) +{ + return __fsl_a008585_read_reg(cntvct_el0); +} +EXPORT_SYMBOL(__fsl_a008585_read_cntvct_el0); +#endif /* CONFIG_FSL_ERRATUM_A008585 */ + static __always_inline void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val, struct clock_event_device *clk) @@ -240,6 +280,40 @@ static __always_inline void set_next_event(const int access, unsigned long evt, arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk); } +#ifdef CONFIG_FSL_ERRATUM_A008585 +static __always_inline void fsl_a008585_set_next_event(const int access, + unsigned long evt, struct clock_event_device *clk) +{ + unsigned long ctrl; + u64 cval = evt + arch_counter_get_cntvct(); + + ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, clk); + ctrl |= ARCH_TIMER_CTRL_ENABLE; + ctrl &= ~ARCH_TIMER_CTRL_IT_MASK; + + if (access == ARCH_TIMER_PHYS_ACCESS) + write_sysreg(cval, cntp_cval_el0); + else if (access == ARCH_TIMER_VIRT_ACCESS) + write_sysreg(cval, cntv_cval_el0); + + arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk); +} + +static int fsl_a008585_set_next_event_virt(unsigned long evt, + struct clock_event_device *clk) +{ + fsl_a008585_set_next_event(ARCH_TIMER_VIRT_ACCESS, evt, clk); + return 0; +} + +static int fsl_a008585_set_next_event_phys(unsigned long evt, + struct clock_event_device *clk) +{ + fsl_a008585_set_next_event(ARCH_TIMER_PHYS_ACCESS, evt, clk); + return 0; +} +#endif /* CONFIG_FSL_ERRATUM_A008585 */ + static int arch_timer_set_next_event_virt(unsigned long evt, struct clock_event_device *clk) { @@ -268,6 +342,19 @@ static int arch_timer_set_next_event_phys_mem(unsigned long evt, return 0; } +static void fsl_a008585_set_sne(struct clock_event_device *clk) +{ +#ifdef CONFIG_FSL_ERRATUM_A008585 + if (!static_branch_unlikely(&arch_timer_read_ool_enabled)) + return; + + if (arch_timer_uses_ppi == VIRT_PPI) + clk->set_next_event = fsl_a008585_set_next_event_virt; + else + clk->set_next_event = fsl_a008585_set_next_event_phys; +#endif +} + static void __arch_timer_setup(unsigned type, struct clock_event_device *clk) { @@ -296,6 +383,8 @@ static void __arch_timer_setup(unsigned type, default: BUG(); } + + fsl_a008585_set_sne(clk); } else { clk->features |= CLOCK_EVT_FEAT_DYNIRQ; clk->name = "arch_mem_timer"; @@ -370,16 +459,33 @@ static bool arch_timer_has_nonsecure_ppi(void) arch_timer_ppi[PHYS_NONSECURE_PPI]); } +static u32 check_ppi_trigger(int irq) +{ + u32 flags = irq_get_trigger_type(irq); + + if (flags != IRQF_TRIGGER_HIGH && flags != IRQF_TRIGGER_LOW) { + pr_warn("WARNING: Invalid trigger for IRQ%d, assuming level low\n", irq); + pr_warn("WARNING: Please fix your firmware\n"); + flags = IRQF_TRIGGER_LOW; + } + + return flags; +} + static int arch_timer_starting_cpu(unsigned int cpu) { struct clock_event_device *clk = this_cpu_ptr(arch_timer_evt); + u32 flags; __arch_timer_setup(ARCH_CP15_TIMER, clk); - enable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], 0); + flags = check_ppi_trigger(arch_timer_ppi[arch_timer_uses_ppi]); + enable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], flags); - if (arch_timer_has_nonsecure_ppi()) - enable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI], 0); + if (arch_timer_has_nonsecure_ppi()) { + flags = check_ppi_trigger(arch_timer_ppi[PHYS_NONSECURE_PPI]); + enable_percpu_irq(arch_timer_ppi[PHYS_NONSECURE_PPI], flags); + } arch_counter_set_user_access(); if (evtstrm_enable) @@ -495,15 +601,19 @@ static void __init arch_counter_register(unsigned type) arch_timer_read_counter = arch_counter_get_cntvct; else arch_timer_read_counter = arch_counter_get_cntpct; - } else { - arch_timer_read_counter = arch_counter_get_cntvct_mem; - /* If the clocksource name is "arch_sys_counter" the - * VDSO will attempt to read the CP15-based counter. - * Ensure this does not happen when CP15-based - * counter is not available. + clocksource_counter.archdata.vdso_direct = true; + +#ifdef CONFIG_FSL_ERRATUM_A008585 + /* + * Don't use the vdso fastpath if errata require using + * the out-of-line counter accessor. */ - clocksource_counter.name = "arch_mem_counter"; + if (static_branch_unlikely(&arch_timer_read_ool_enabled)) + clocksource_counter.archdata.vdso_direct = false; +#endif + } else { + arch_timer_read_counter = arch_counter_get_cntvct_mem; } start_count = arch_timer_read_counter(); @@ -780,6 +890,15 @@ static int __init arch_timer_of_init(struct device_node *np) arch_timer_c3stop = !of_property_read_bool(np, "always-on"); +#ifdef CONFIG_FSL_ERRATUM_A008585 + if (fsl_a008585_enable < 0) + fsl_a008585_enable = of_property_read_bool(np, "fsl,erratum-a008585"); + if (fsl_a008585_enable) { + static_branch_enable(&arch_timer_read_ool_enabled); + pr_info("Enabling workaround for FSL erratum A-008585\n"); + } +#endif + /* * If we cannot rely on firmware initializing the timer registers then * we should use the physical timers instead. |