// SPDX-License-Identifier: GPL-2.0-only/* * linux/drivers/clocksource/arm_arch_timer.c * * Copyright (C) 2011 ARM Ltd. * All Rights Reserved */ #define pr_fmt(fmt) "arch_timer: " fmt #include <linux/init.h>#include <linux/kernel.h>#include <linux/device.h>#include <linux/smp.h>#include <linux/cpu.h>#include <linux/cpu_pm.h>#include <linux/clockchips.h>#include <linux/clocksource.h>#include <linux/clocksource_ids.h>#include <linux/interrupt.h>#include <linux/kstrtox.h>#include <linux/of_irq.h>#include <linux/of_address.h>#include <linux/io.h>#include <linux/slab.h>#include <linux/sched/clock.h>#include <linux/sched_clock.h>#include <linux/acpi.h>#include <linux/arm-smccc.h>#include <linux/ptp_kvm.h> #include <asm/arch_timer.h>#include <asm/virt.h> #include <clocksource/arm_arch_timer.h> /* * The minimum amount of time a generic counter is guaranteed to not roll over * (40 years) */#define MIN_ROLLOVER_SECS (40ULL * 365 * 24 * 3600) static u32 arch_timer_rate __ro_after_init;static int arch_timer_ppi[ARCH_TIMER_MAX_TIMER_PPI] __ro_after_init; static const char *arch_timer_ppi_names[ARCH_TIMER_MAX_TIMER_PPI] = { [ARCH_TIMER_PHYS_SECURE_PPI] = "sec-phys", [ARCH_TIMER_PHYS_NONSECURE_PPI] = "phys", [ARCH_TIMER_VIRT_PPI] = "virt", [ARCH_TIMER_HYP_PPI] = "hyp-phys", [ARCH_TIMER_HYP_VIRT_PPI] = "hyp-virt",}; static struct clock_event_device __percpu *arch_timer_evt; static enum arch_timer_ppi_nr arch_timer_uses_ppi __ro_after_init = ARCH_TIMER_VIRT_PPI;static bool arch_timer_c3stop __ro_after_init;static bool arch_counter_suspend_stop __ro_after_init;static enum vdso_clock_mode vdso_default = VDSO_CLOCKMODE_ARCHTIMER; static cpumask_t evtstrm_available = CPU_MASK_NONE;static bool evtstrm_enable __ro_after_init = IS_ENABLED(CONFIG_ARM_ARCH_TIMER_EVTSTREAM); static int __init early_evtstrm_cfg(char *buf){ return kstrtobool(buf, &evtstrm_enable);}early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg); /* * Makes an educated guess at a valid counter width based on the Generic Timer * specification. Of note: * 1) the system counter is at least 56 bits wide * 2) a roll-over time of not less than 40 years * * See 'ARM DDI 0487G.a D11.1.2 ("The system counter")' for more details. */static int arch_counter_get_width(void){ u64 min_cycles = MIN_ROLLOVER_SECS * arch_timer_rate; /* guarantee the returned width is within the valid range */ return clamp_val(ilog2(min_cycles - 1) + 1, 56, 64);} /* * Architected system timer support. */static noinstr u64 raw_counter_get_cntpct_stable(void){ return __arch_counter_get_cntpct_stable();} static notrace u64 arch_counter_get_cntpct_stable(void){ u64 val; preempt_disable_notrace(); val = __arch_counter_get_cntpct_stable(); preempt_enable_notrace(); return val;} static noinstr u64 arch_counter_get_cntpct(void){ return __arch_counter_get_cntpct();} static noinstr u64 raw_counter_get_cntvct_stable(void){ return __arch_counter_get_cntvct_stable();} static notrace u64 arch_counter_get_cntvct_stable(void){ u64 val; preempt_disable_notrace(); val = __arch_counter_get_cntvct_stable(); preempt_enable_notrace(); return val;} static noinstr u64 arch_counter_get_cntvct(void){ return __arch_counter_get_cntvct();} /* * Default to cp15 based access because arm64 uses this function for * sched_clock() before DT is probed and the cp15 method is guaranteed * to exist on arm64. arm doesn't use this before DT is probed so even * if we don't have the cp15 accessors we won't have a problem. */u64 (*arch_timer_read_counter)(void) __ro_after_init = arch_counter_get_cntvct;EXPORT_SYMBOL_GPL(arch_timer_read_counter); static u64 arch_counter_read(struct clocksource *cs){ return arch_timer_read_counter();} static u64 arch_counter_read_cc(struct cyclecounter *cc){ return arch_timer_read_counter();} static struct clocksource clocksource_counter = { .name = "arch_sys_counter", .id = CSID_ARM_ARCH_COUNTER, .rating = 400, .read = arch_counter_read, .flags = CLOCK_SOURCE_IS_CONTINUOUS,}; static struct cyclecounter cyclecounter __ro_after_init = { .read = arch_counter_read_cc,}; struct ate_acpi_oem_info { char oem_id[ACPI_OEM_ID_SIZE + 1]; char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1]; u32 oem_revision;}; #ifdef CONFIG_FSL_ERRATUM_A008585/* * The number of retries is an arbitrary value well beyond the highest number * of iterations the loop has been observed to take. */#define __fsl_a008585_read_reg(reg) ({ \ u64 _old, _new; \ int _retries = 200; \ \ do { \ _old = read_sysreg(reg); \ _new = read_sysreg(reg); \ _retries--; \ } while (unlikely(_old != _new) && _retries); \ \ WARN_ON_ONCE(!_retries); \ _new; \}) static u64 notrace fsl_a008585_read_cntpct_el0(void){ return __fsl_a008585_read_reg(cntpct_el0);} static u64 notrace fsl_a008585_read_cntvct_el0(void){ return __fsl_a008585_read_reg(cntvct_el0);}#endif #ifdef CONFIG_HISILICON_ERRATUM_161010101/* * Verify whether the value of the second read is larger than the first by * less than 32 is the only way to confirm the value is correct, so clear the * lower 5 bits to check whether the difference is greater than 32 or not. * Theoretically the erratum should not occur more than twice in succession * when reading the system counter, but it is possible that some interrupts * may lead to more than twice read errors, triggering the warning, so setting * the number of retries far beyond the number of iterations the loop has been * observed to take. */#define __hisi_161010101_read_reg(reg) ({ \ u64 _old, _new; \ int _retries = 50; \ \ do { \ _old = read_sysreg(reg); \ _new = read_sysreg(reg); \ _retries--; \ } while (unlikely((_new - _old) >> 5) && _retries); \ \ WARN_ON_ONCE(!_retries); \ _new; \}) static u64 notrace hisi_161010101_read_cntpct_el0(void){ return __hisi_161010101_read_reg(cntpct_el0);} static u64 notrace hisi_161010101_read_cntvct_el0(void){ return __hisi_161010101_read_reg(cntvct_el0);} static const struct ate_acpi_oem_info hisi_161010101_oem_info[] = { /* * Note that trailing spaces are required to properly match * the OEM table information. */ { .oem_id = "HISI ", .oem_table_id = "HIP05 ", .oem_revision = 0, }, { .oem_id = "HISI ", .oem_table_id = "HIP06 ", .oem_revision = 0, }, { .oem_id = "HISI ", .oem_table_id = "HIP07 ", .oem_revision = 0, }, { /* Sentinel indicating the end of the OEM array */ },};#endif #ifdef CONFIG_ARM64_ERRATUM_858921static u64 notrace arm64_858921_read_cntpct_el0(void){ u64 old, new; old = read_sysreg(cntpct_el0); new = read_sysreg(cntpct_el0); return (((old ^ new) >> 32) & 1) ? old : new;} static u64 notrace arm64_858921_read_cntvct_el0(void){ u64 old, new; old = read_sysreg(cntvct_el0); new = read_sysreg(cntvct_el0); return (((old ^ new) >> 32) & 1) ? old : new;}#endif #ifdef CONFIG_SUN50I_ERRATUM_UNKNOWN1/* * The low bits of the counter registers are indeterminate while bit 10 or * greater is rolling over. Since the counter value can jump both backward * (7ff -> 000 -> 800) and forward (7ff -> fff -> 800), ignore register values * with all ones or all zeros in the low bits. Bound the loop by the maximum * number of CPU cycles in 3 consecutive 24 MHz counter periods. */#define __sun50i_a64_read_reg(reg) ({ \ u64 _val; \ int _retries = 150; \ \ do { \ _val = read_sysreg(reg); \ _retries--; \ } while (((_val + 1) & GENMASK(8, 0)) <= 1 && _retries); \ \ WARN_ON_ONCE(!_retries); \ _val; \}) static u64 notrace sun50i_a64_read_cntpct_el0(void){ return __sun50i_a64_read_reg(cntpct_el0);} static u64 notrace sun50i_a64_read_cntvct_el0(void){ return __sun50i_a64_read_reg(cntvct_el0);}#endif #ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUNDDEFINE_PER_CPU(const struct arch_timer_erratum_workaround *, timer_unstable_counter_workaround);EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround); static atomic_t timer_unstable_counter_workaround_in_use = ATOMIC_INIT(0); /* * Force the inlining of this function so that the register accesses * can be themselves correctly inlined. */static __always_inlinevoid erratum_set_next_event_generic(const int access, unsigned long evt, struct clock_event_device *clk){ unsigned long ctrl; u64 cval; ctrl = arch_timer_reg_read_cp15(access, ARCH_TIMER_REG_CTRL); ctrl |= ARCH_TIMER_CTRL_ENABLE; ctrl &= ~ARCH_TIMER_CTRL_IT_MASK; if (access == ARCH_TIMER_PHYS_ACCESS) { cval = evt + arch_counter_get_cntpct_stable(); write_sysreg(cval, cntp_cval_el0); } else { cval = evt + arch_counter_get_cntvct_stable(); write_sysreg(cval, cntv_cval_el0); } arch_timer_reg_write_cp15(access, ARCH_TIMER_REG_CTRL, ctrl);} static __maybe_unused int erratum_set_next_event_virt(unsigned long evt, struct clock_event_device *clk){ erratum_set_next_event_generic(ARCH_TIMER_VIRT_ACCESS, evt, clk); return 0;} static __maybe_unused int erratum_set_next_event_phys(unsigned long evt, struct clock_event_device *clk){ erratum_set_next_event_generic(ARCH_TIMER_PHYS_ACCESS, evt, clk); return 0;} static const struct arch_timer_erratum_workaround ool_workarounds[] = {#ifdef CONFIG_FSL_ERRATUM_A008585 { .match_type = ate_match_dt, .id = "fsl,erratum-a008585", .desc = "Freescale erratum a005858", .read_cntpct_el0 = fsl_a008585_read_cntpct_el0, .read_cntvct_el0 = fsl_a008585_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_phys, .set_next_event_virt = erratum_set_next_event_virt, },#endif#ifdef CONFIG_HISILICON_ERRATUM_161010101 { .match_type = ate_match_dt, .id = "hisilicon,erratum-161010101", .desc = "HiSilicon erratum 161010101", .read_cntpct_el0 = hisi_161010101_read_cntpct_el0, .read_cntvct_el0 = hisi_161010101_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_phys, .set_next_event_virt = erratum_set_next_event_virt, }, { .match_type = ate_match_acpi_oem_info, .id = hisi_161010101_oem_info, .desc = "HiSilicon erratum 161010101", .read_cntpct_el0 = hisi_161010101_read_cntpct_el0, .read_cntvct_el0 = hisi_161010101_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_phys, .set_next_event_virt = erratum_set_next_event_virt, },#endif#ifdef CONFIG_ARM64_ERRATUM_858921 { .match_type = ate_match_local_cap_id, .id = (void *)ARM64_WORKAROUND_858921, .desc = "ARM erratum 858921", .read_cntpct_el0 = arm64_858921_read_cntpct_el0, .read_cntvct_el0 = arm64_858921_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_phys, .set_next_event_virt = erratum_set_next_event_virt, },#endif#ifdef CONFIG_SUN50I_ERRATUM_UNKNOWN1 { .match_type = ate_match_dt, .id = "allwinner,erratum-unknown1", .desc = "Allwinner erratum UNKNOWN1", .read_cntpct_el0 = sun50i_a64_read_cntpct_el0, .read_cntvct_el0 = sun50i_a64_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_phys, .set_next_event_virt = erratum_set_next_event_virt, },#endif#ifdef CONFIG_ARM64_ERRATUM_1418040 { .match_type = ate_match_local_cap_id, .id = (void *)ARM64_WORKAROUND_1418040, .desc = "ARM erratum 1418040", .disable_compat_vdso = true, },#endif}; typedef bool (*ate_match_fn_t)(const struct arch_timer_erratum_workaround *, const void *); staticbool arch_timer_check_dt_erratum(const struct arch_timer_erratum_workaround *wa, const void *arg){ const struct device_node *np = arg; return of_property_read_bool(np, wa->id);} staticbool arch_timer_check_local_cap_erratum(const struct arch_timer_erratum_workaround *wa, const void *arg){ return this_cpu_has_cap((uintptr_t)wa->id);} staticbool arch_timer_check_acpi_oem_erratum(const struct arch_timer_erratum_workaround *wa, const void *arg){ static const struct ate_acpi_oem_info empty_oem_info = {}; const struct ate_acpi_oem_info *info = wa->id; const struct acpi_table_header *table = arg; /* Iterate over the ACPI OEM info array, looking for a match */ while (memcmp(info, &empty_oem_info, sizeof(*info))) { if (!memcmp(info->oem_id, table->oem_id, ACPI_OEM_ID_SIZE) && !memcmp(info->oem_table_id, table->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) && info->oem_revision == table->oem_revision) return true; info++; } return false;} static const struct arch_timer_erratum_workaround *arch_timer_iterate_errata(enum arch_timer_erratum_match_type type, ate_match_fn_t match_fn, void *arg){ int i; for (i = 0; i < ARRAY_SIZE(ool_workarounds); i++) { if (ool_workarounds[i].match_type != type) continue; if (match_fn(&ool_workarounds[i], arg)) return &ool_workarounds[i]; } return NULL;} staticvoid arch_timer_enable_workaround(const struct arch_timer_erratum_workaround *wa, bool local){ int i; if (local) { __this_cpu_write(timer_unstable_counter_workaround, wa); } else { for_each_possible_cpu(i) per_cpu(timer_unstable_counter_workaround, i) = wa; } if (wa->read_cntvct_el0 || wa->read_cntpct_el0) atomic_set(&timer_unstable_counter_workaround_in_use, 1); /* * Don't use the vdso fastpath if errata require using the * out-of-line counter accessor. We may change our mind pretty * late in the game (with a per-CPU erratum, for example), so * change both the default value and the vdso itself. */ if (wa->read_cntvct_el0) { clocksource_counter.vdso_clock_mode = VDSO_CLOCKMODE_NONE; vdso_default = VDSO_CLOCKMODE_NONE; } else if (wa->disable_compat_vdso && vdso_default != VDSO_CLOCKMODE_NONE) { vdso_default = VDSO_CLOCKMODE_ARCHTIMER_NOCOMPAT;Lines 1–500 of 1305. Load more
// SPDX-License-Identifier: GPL-2.0-only /* * linux/drivers/clocksource/arm_arch_timer.c * * Copyright (C) 2011 ARM Ltd. * All Rights Reserved */ #define pr_fmt(fmt) "arch_timer: " fmt #include <linux/init.h> #include <linux/kernel.h> #include <linux/device.h> #include <linux/smp.h> #include <linux/cpu.h> #include <linux/cpu_pm.h> #include <linux/clockchips.h> #include <linux/clocksource.h> #include <linux/clocksource_ids.h> #include <linux/interrupt.h> #include <linux/kstrtox.h> #include <linux/of_irq.h> #include <linux/of_address.h> #include <linux/io.h> #include <linux/slab.h> #include <linux/sched/clock.h> #include <linux/sched_clock.h> #include <linux/acpi.h> #include <linux/arm-smccc.h> #include <linux/ptp_kvm.h> #include <asm/arch_timer.h> #include <asm/virt.h> #include <clocksource/arm_arch_timer.h> /* * The minimum amount of time a generic counter is guaranteed to not roll over * (40 years) */ #define MIN_ROLLOVER_SECS (40ULL * 365 * 24 * 3600) static u32 arch_timer_rate __ro_after_init; static int arch_timer_ppi[ARCH_TIMER_MAX_TIMER_PPI] __ro_after_init; static const char *arch_timer_ppi_names[ARCH_TIMER_MAX_TIMER_PPI] = { [ARCH_TIMER_PHYS_SECURE_PPI] = "sec-phys", [ARCH_TIMER_PHYS_NONSECURE_PPI] = "phys", [ARCH_TIMER_VIRT_PPI] = "virt", [ARCH_TIMER_HYP_PPI] = "hyp-phys", [ARCH_TIMER_HYP_VIRT_PPI] = "hyp-virt", }; static struct clock_event_device __percpu *arch_timer_evt; static enum arch_timer_ppi_nr arch_timer_uses_ppi __ro_after_init = ARCH_TIMER_VIRT_PPI; static bool arch_timer_c3stop __ro_after_init; static bool arch_counter_suspend_stop __ro_after_init; static enum vdso_clock_mode vdso_default = VDSO_CLOCKMODE_ARCHTIMER; static cpumask_t evtstrm_available = CPU_MASK_NONE; static bool evtstrm_enable __ro_after_init = IS_ENABLED(CONFIG_ARM_ARCH_TIMER_EVTSTREAM); static int __init early_evtstrm_cfg(char *buf) { return kstrtobool(buf, &evtstrm_enable); } early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg); /* * Makes an educated guess at a valid counter width based on the Generic Timer * specification. Of note: * 1) the system counter is at least 56 bits wide * 2) a roll-over time of not less than 40 years * * See 'ARM DDI 0487G.a D11.1.2 ("The system counter")' for more details. */ static int arch_counter_get_width(void) { u64 min_cycles = MIN_ROLLOVER_SECS * arch_timer_rate; /* guarantee the returned width is within the valid range */ return clamp_val(ilog2(min_cycles - 1) + 1, 56, 64); } /* * Architected system timer support. */ static noinstr u64 raw_counter_get_cntpct_stable(void) { return __arch_counter_get_cntpct_stable(); } static notrace u64 arch_counter_get_cntpct_stable(void) { u64 val; preempt_disable_notrace(); val = __arch_counter_get_cntpct_stable(); preempt_enable_notrace(); return val; } static noinstr u64 arch_counter_get_cntpct(void) { return __arch_counter_get_cntpct(); } static noinstr u64 raw_counter_get_cntvct_stable(void) { return __arch_counter_get_cntvct_stable(); } static notrace u64 arch_counter_get_cntvct_stable(void) { u64 val; preempt_disable_notrace(); val = __arch_counter_get_cntvct_stable(); preempt_enable_notrace(); return val; } static noinstr u64 arch_counter_get_cntvct(void) { return __arch_counter_get_cntvct(); } /* * Default to cp15 based access because arm64 uses this function for * sched_clock() before DT is probed and the cp15 method is guaranteed * to exist on arm64. arm doesn't use this before DT is probed so even * if we don't have the cp15 accessors we won't have a problem. */ u64 (*arch_timer_read_counter)(void) __ro_after_init = arch_counter_get_cntvct; EXPORT_SYMBOL_GPL(arch_timer_read_counter); static u64 arch_counter_read(struct clocksource *cs) { return arch_timer_read_counter(); } static u64 arch_counter_read_cc(struct cyclecounter *cc) { return arch_timer_read_counter(); } static struct clocksource clocksource_counter = { .name = "arch_sys_counter", .id = CSID_ARM_ARCH_COUNTER, .rating = 400, .read = arch_counter_read, .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; static struct cyclecounter cyclecounter __ro_after_init = { .read = arch_counter_read_cc, }; struct ate_acpi_oem_info { char oem_id[ACPI_OEM_ID_SIZE + 1]; char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1]; u32 oem_revision; }; #ifdef CONFIG_FSL_ERRATUM_A008585 /* * The number of retries is an arbitrary value well beyond the highest number * of iterations the loop has been observed to take. */ #define __fsl_a008585_read_reg(reg) ({ \ u64 _old, _new; \ int _retries = 200; \ \ do { \ _old = read_sysreg(reg); \ _new = read_sysreg(reg); \ _retries--; \ } while (unlikely(_old != _new) && _retries); \ \ WARN_ON_ONCE(!_retries); \ _new; \ }) static u64 notrace fsl_a008585_read_cntpct_el0(void) { return __fsl_a008585_read_reg(cntpct_el0); } static u64 notrace fsl_a008585_read_cntvct_el0(void) { return __fsl_a008585_read_reg(cntvct_el0); } #endif #ifdef CONFIG_HISILICON_ERRATUM_161010101 /* * Verify whether the value of the second read is larger than the first by * less than 32 is the only way to confirm the value is correct, so clear the * lower 5 bits to check whether the difference is greater than 32 or not. * Theoretically the erratum should not occur more than twice in succession * when reading the system counter, but it is possible that some interrupts * may lead to more than twice read errors, triggering the warning, so setting * the number of retries far beyond the number of iterations the loop has been * observed to take. */ #define __hisi_161010101_read_reg(reg) ({ \ u64 _old, _new; \ int _retries = 50; \ \ do { \ _old = read_sysreg(reg); \ _new = read_sysreg(reg); \ _retries--; \ } while (unlikely((_new - _old) >> 5) && _retries); \ \ WARN_ON_ONCE(!_retries); \ _new; \ }) static u64 notrace hisi_161010101_read_cntpct_el0(void) { return __hisi_161010101_read_reg(cntpct_el0); } static u64 notrace hisi_161010101_read_cntvct_el0(void) { return __hisi_161010101_read_reg(cntvct_el0); } static const struct ate_acpi_oem_info hisi_161010101_oem_info[] = { /* * Note that trailing spaces are required to properly match * the OEM table information. */ { .oem_id = "HISI ", .oem_table_id = "HIP05 ", .oem_revision = 0, }, { .oem_id = "HISI ", .oem_table_id = "HIP06 ", .oem_revision = 0, }, { .oem_id = "HISI ", .oem_table_id = "HIP07 ", .oem_revision = 0, }, { /* Sentinel indicating the end of the OEM array */ }, }; #endif #ifdef CONFIG_ARM64_ERRATUM_858921 static u64 notrace arm64_858921_read_cntpct_el0(void) { u64 old, new; old = read_sysreg(cntpct_el0); new = read_sysreg(cntpct_el0); return (((old ^ new) >> 32) & 1) ? old : new; } static u64 notrace arm64_858921_read_cntvct_el0(void) { u64 old, new; old = read_sysreg(cntvct_el0); new = read_sysreg(cntvct_el0); return (((old ^ new) >> 32) & 1) ? old : new; } #endif #ifdef CONFIG_SUN50I_ERRATUM_UNKNOWN1 /* * The low bits of the counter registers are indeterminate while bit 10 or * greater is rolling over. Since the counter value can jump both backward * (7ff -> 000 -> 800) and forward (7ff -> fff -> 800), ignore register values * with all ones or all zeros in the low bits. Bound the loop by the maximum * number of CPU cycles in 3 consecutive 24 MHz counter periods. */ #define __sun50i_a64_read_reg(reg) ({ \ u64 _val; \ int _retries = 150; \ \ do { \ _val = read_sysreg(reg); \ _retries--; \ } while (((_val + 1) & GENMASK(8, 0)) <= 1 && _retries); \ \ WARN_ON_ONCE(!_retries); \ _val; \ }) static u64 notrace sun50i_a64_read_cntpct_el0(void) { return __sun50i_a64_read_reg(cntpct_el0); } static u64 notrace sun50i_a64_read_cntvct_el0(void) { return __sun50i_a64_read_reg(cntvct_el0); } #endif #ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND DEFINE_PER_CPU(const struct arch_timer_erratum_workaround *, timer_unstable_counter_workaround); EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround); static atomic_t timer_unstable_counter_workaround_in_use = ATOMIC_INIT(0); /* * Force the inlining of this function so that the register accesses * can be themselves correctly inlined. */ static __always_inline void erratum_set_next_event_generic(const int access, unsigned long evt, struct clock_event_device *clk) { unsigned long ctrl; u64 cval; ctrl = arch_timer_reg_read_cp15(access, ARCH_TIMER_REG_CTRL); ctrl |= ARCH_TIMER_CTRL_ENABLE; ctrl &= ~ARCH_TIMER_CTRL_IT_MASK; if (access == ARCH_TIMER_PHYS_ACCESS) { cval = evt + arch_counter_get_cntpct_stable(); write_sysreg(cval, cntp_cval_el0); } else { cval = evt + arch_counter_get_cntvct_stable(); write_sysreg(cval, cntv_cval_el0); } arch_timer_reg_write_cp15(access, ARCH_TIMER_REG_CTRL, ctrl); } static __maybe_unused int erratum_set_next_event_virt(unsigned long evt, struct clock_event_device *clk) { erratum_set_next_event_generic(ARCH_TIMER_VIRT_ACCESS, evt, clk); return 0; } static __maybe_unused int erratum_set_next_event_phys(unsigned long evt, struct clock_event_device *clk) { erratum_set_next_event_generic(ARCH_TIMER_PHYS_ACCESS, evt, clk); return 0; } static const struct arch_timer_erratum_workaround ool_workarounds[] = { #ifdef CONFIG_FSL_ERRATUM_A008585 { .match_type = ate_match_dt, .id = "fsl,erratum-a008585", .desc = "Freescale erratum a005858", .read_cntpct_el0 = fsl_a008585_read_cntpct_el0, .read_cntvct_el0 = fsl_a008585_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_phys, .set_next_event_virt = erratum_set_next_event_virt, }, #endif #ifdef CONFIG_HISILICON_ERRATUM_161010101 { .match_type = ate_match_dt, .id = "hisilicon,erratum-161010101", .desc = "HiSilicon erratum 161010101", .read_cntpct_el0 = hisi_161010101_read_cntpct_el0, .read_cntvct_el0 = hisi_161010101_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_phys, .set_next_event_virt = erratum_set_next_event_virt, }, { .match_type = ate_match_acpi_oem_info, .id = hisi_161010101_oem_info, .desc = "HiSilicon erratum 161010101", .read_cntpct_el0 = hisi_161010101_read_cntpct_el0, .read_cntvct_el0 = hisi_161010101_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_phys, .set_next_event_virt = erratum_set_next_event_virt, }, #endif #ifdef CONFIG_ARM64_ERRATUM_858921 { .match_type = ate_match_local_cap_id, .id = (void *)ARM64_WORKAROUND_858921, .desc = "ARM erratum 858921", .read_cntpct_el0 = arm64_858921_read_cntpct_el0, .read_cntvct_el0 = arm64_858921_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_phys, .set_next_event_virt = erratum_set_next_event_virt, }, #endif #ifdef CONFIG_SUN50I_ERRATUM_UNKNOWN1 { .match_type = ate_match_dt, .id = "allwinner,erratum-unknown1", .desc = "Allwinner erratum UNKNOWN1", .read_cntpct_el0 = sun50i_a64_read_cntpct_el0, .read_cntvct_el0 = sun50i_a64_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_phys, .set_next_event_virt = erratum_set_next_event_virt, }, #endif #ifdef CONFIG_ARM64_ERRATUM_1418040 { .match_type = ate_match_local_cap_id, .id = (void *)ARM64_WORKAROUND_1418040, .desc = "ARM erratum 1418040", .disable_compat_vdso = true, }, #endif }; typedef bool (*ate_match_fn_t)(const struct arch_timer_erratum_workaround *, const void *); static bool arch_timer_check_dt_erratum(const struct arch_timer_erratum_workaround *wa, const void *arg) { const struct device_node *np = arg; return of_property_read_bool(np, wa->id); } static bool arch_timer_check_local_cap_erratum(const struct arch_timer_erratum_workaround *wa, const void *arg) { return this_cpu_has_cap((uintptr_t)wa->id); } static bool arch_timer_check_acpi_oem_erratum(const struct arch_timer_erratum_workaround *wa, const void *arg) { static const struct ate_acpi_oem_info empty_oem_info = {}; const struct ate_acpi_oem_info *info = wa->id; const struct acpi_table_header *table = arg; /* Iterate over the ACPI OEM info array, looking for a match */ while (memcmp(info, &empty_oem_info, sizeof(*info))) { if (!memcmp(info->oem_id, table->oem_id, ACPI_OEM_ID_SIZE) && !memcmp(info->oem_table_id, table->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) && info->oem_revision == table->oem_revision) return true; info++; } return false; } static const struct arch_timer_erratum_workaround * arch_timer_iterate_errata(enum arch_timer_erratum_match_type type, ate_match_fn_t match_fn, void *arg) { int i; for (i = 0; i < ARRAY_SIZE(ool_workarounds); i++) { if (ool_workarounds[i].match_type != type) continue; if (match_fn(&ool_workarounds[i], arg)) return &ool_workarounds[i]; } return NULL; } static void arch_timer_enable_workaround(const struct arch_timer_erratum_workaround *wa, bool local) { int i; if (local) { __this_cpu_write(timer_unstable_counter_workaround, wa); } else { for_each_possible_cpu(i) per_cpu(timer_unstable_counter_workaround, i) = wa; } if (wa->read_cntvct_el0 || wa->read_cntpct_el0) atomic_set(&timer_unstable_counter_workaround_in_use, 1); /* * Don't use the vdso fastpath if errata require using the * out-of-line counter accessor. We may change our mind pretty * late in the game (with a per-CPU erratum, for example), so * change both the default value and the vdso itself. */ if (wa->read_cntvct_el0) { clocksource_counter.vdso_clock_mode = VDSO_CLOCKMODE_NONE; vdso_default = VDSO_CLOCKMODE_NONE; } else if (wa->disable_compat_vdso && vdso_default != VDSO_CLOCKMODE_NONE) { vdso_default = VDSO_CLOCKMODE_ARCHTIMER_NOCOMPAT;