static bool arch_timer_c3stop;
static bool arch_timer_mem_use_virtual;
static bool arch_counter_suspend_stop;
+static bool vdso_default = true;
static bool evtstrm_enable = IS_ENABLED(CONFIG_ARM_ARCH_TIMER_EVTSTREAM);
* 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)
return val;
}
+/*
+ * 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) = arch_counter_get_cntvct;
+
+static u64 arch_counter_read(struct clocksource *cs)
+{
+ return arch_timer_read_counter();
+}
+
+static u64 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),
+};
+
+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 u32 notrace fsl_a008585_read_cntp_tval_el0(void)
+{
+ return __fsl_a008585_read_reg(cntp_tval_el0);
+}
+
+static u32 notrace fsl_a008585_read_cntv_tval_el0(void)
+{
+ return __fsl_a008585_read_reg(cntv_tval_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 u32 notrace hisi_161010101_read_cntp_tval_el0(void)
+{
+ return __hisi_161010101_read_reg(cntp_tval_el0);
+}
+
+static u32 notrace hisi_161010101_read_cntv_tval_el0(void)
+{
+ return __hisi_161010101_read_reg(cntv_tval_el0);
+}
+
+static u64 notrace hisi_161010101_read_cntvct_el0(void)
+{
+ return __hisi_161010101_read_reg(cntvct_el0);
+}
+#endif
+
+#ifdef CONFIG_ARM64_ERRATUM_858921
+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_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);
+
+DEFINE_STATIC_KEY_FALSE(arch_timer_read_ool_enabled);
+EXPORT_SYMBOL_GPL(arch_timer_read_ool_enabled);
+
+static void erratum_set_next_event_tval_generic(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
+ write_sysreg(cval, cntv_cval_el0);
+
+ arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
+}
+
+static int erratum_set_next_event_tval_virt(unsigned long evt,
+ struct clock_event_device *clk)
+{
+ erratum_set_next_event_tval_generic(ARCH_TIMER_VIRT_ACCESS, evt, clk);
+ return 0;
+}
+
+static int erratum_set_next_event_tval_phys(unsigned long evt,
+ struct clock_event_device *clk)
+{
+ erratum_set_next_event_tval_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_cntp_tval_el0 = fsl_a008585_read_cntp_tval_el0,
+ .read_cntv_tval_el0 = fsl_a008585_read_cntv_tval_el0,
+ .read_cntvct_el0 = fsl_a008585_read_cntvct_el0,
+ .set_next_event_phys = erratum_set_next_event_tval_phys,
+ .set_next_event_virt = erratum_set_next_event_tval_virt,
+ },
+#endif
+#ifdef CONFIG_HISILICON_ERRATUM_161010101
+ {
+ .match_type = ate_match_dt,
+ .id = "hisilicon,erratum-161010101",
+ .desc = "HiSilicon erratum 161010101",
+ .read_cntp_tval_el0 = hisi_161010101_read_cntp_tval_el0,
+ .read_cntv_tval_el0 = hisi_161010101_read_cntv_tval_el0,
+ .read_cntvct_el0 = hisi_161010101_read_cntvct_el0,
+ .set_next_event_phys = erratum_set_next_event_tval_phys,
+ .set_next_event_virt = erratum_set_next_event_tval_virt,
+ },
+#endif
+#ifdef CONFIG_ARM64_ERRATUM_858921
+ {
+ .match_type = ate_match_local_cap_id,
+ .id = (void *)ARM64_WORKAROUND_858921,
+ .desc = "ARM erratum 858921",
+ .read_cntvct_el0 = arm64_858921_read_cntvct_el0,
+ },
+#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_global_cap_erratum(const struct arch_timer_erratum_workaround *wa,
+ const void *arg)
+{
+ return cpus_have_cap((uintptr_t)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;
+ }
+
+ static_branch_enable(&arch_timer_read_ool_enabled);
+
+ /*
+ * 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.archdata.vdso_direct = false;
+ vdso_default = false;
+ }
+}
+
+static void arch_timer_check_ool_workaround(enum arch_timer_erratum_match_type type,
+ void *arg)
+{
+ const struct arch_timer_erratum_workaround *wa;
+ ate_match_fn_t match_fn = NULL;
+ bool local = false;
+
+ switch (type) {
+ case ate_match_dt:
+ match_fn = arch_timer_check_dt_erratum;
+ break;
+ case ate_match_global_cap_id:
+ match_fn = arch_timer_check_global_cap_erratum;
+ break;
+ case ate_match_local_cap_id:
+ match_fn = arch_timer_check_local_cap_erratum;
+ local = true;
+ break;
+ case ate_match_acpi_oem_info:
+ match_fn = arch_timer_check_acpi_oem_erratum;
+ break;
+ }
+
+ wa = arch_timer_iterate_errata(type, match_fn, arg);
+ if (!wa)
+ return;
+
+ if (static_branch_unlikely(&arch_timer_read_ool_enabled)) {
+ const struct arch_timer_erratum_workaround *__wa;
+ __wa = __this_cpu_read(timer_unstable_counter_workaround);
+ if (__wa && wa != __wa)
+ pr_warn("Can't enable workaround for %s (clashes with %s\n)",
+ wa->desc, __wa->desc);
+
+ if (__wa)
+ return;
+ }
+
+ arch_timer_enable_workaround(wa, local);
+ pr_info("Enabling %s workaround for %s\n",
+ local ? "local" : "global", wa->desc);
+}
+
+#define erratum_handler(fn, r, ...) \
+({ \
+ bool __val; \
+ if (needs_unstable_timer_counter_workaround()) { \
+ const struct arch_timer_erratum_workaround *__wa; \
+ __wa = __this_cpu_read(timer_unstable_counter_workaround); \
+ if (__wa && __wa->fn) { \
+ r = __wa->fn(__VA_ARGS__); \
+ __val = true; \
+ } else { \
+ __val = false; \
+ } \
+ } else { \
+ __val = false; \
+ } \
+ __val; \
+})
+
+static bool arch_timer_this_cpu_has_cntvct_wa(void)
+{
+ const struct arch_timer_erratum_workaround *wa;
+
+ wa = __this_cpu_read(timer_unstable_counter_workaround);
+ return wa && wa->read_cntvct_el0;
+}
+#else
+#define arch_timer_check_ool_workaround(t,a) do { } while(0)
+#define erratum_set_next_event_tval_virt(...) ({BUG(); 0;})
+#define erratum_set_next_event_tval_phys(...) ({BUG(); 0;})
+#define erratum_handler(fn, r, ...) ({false;})
+#define arch_timer_this_cpu_has_cntvct_wa() ({false;})
+#endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */
+
static __always_inline irqreturn_t timer_handler(const int access,
struct clock_event_device *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)
{
+ int ret;
+
+ if (erratum_handler(set_next_event_virt, ret, evt, clk))
+ return ret;
+
set_next_event(ARCH_TIMER_VIRT_ACCESS, evt, clk);
return 0;
}
static int arch_timer_set_next_event_phys(unsigned long evt,
struct clock_event_device *clk)
{
+ int ret;
+
+ if (erratum_handler(set_next_event_phys, ret, evt, clk))
+ return ret;
+
set_next_event(ARCH_TIMER_PHYS_ACCESS, evt, clk);
return 0;
}
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)
{
BUG();
}
- fsl_a008585_set_sne(clk);
+ arch_timer_check_ool_workaround(ate_match_local_cap_id, NULL);
} else {
clk->features |= CLOCK_EVT_FEAT_DYNIRQ;
clk->name = "arch_mem_timer";
| ARCH_TIMER_VIRT_EVT_EN
| ARCH_TIMER_USR_PCT_ACCESS_EN);
- /* Enable user access to the virtual counter */
- cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN;
+ /*
+ * Enable user access to the virtual counter if it doesn't
+ * need to be workaround. The vdso may have been already
+ * disabled though.
+ */
+ if (arch_timer_this_cpu_has_cntvct_wa())
+ pr_info("CPU%d: Trapping CNTVCT access\n", smp_processor_id());
+ else
+ cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN;
arch_timer_set_cntkctl(cntkctl);
}
return ((u64) vct_hi << 32) | vct_lo;
}
-/*
- * 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) = arch_counter_get_cntvct;
-
-static u64 arch_counter_read(struct clocksource *cs)
-{
- return arch_timer_read_counter();
-}
-
-static u64 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 arch_timer_kvm_info arch_timer_kvm_info;
struct arch_timer_kvm_info *arch_timer_get_kvm_info(void)
else
arch_timer_read_counter = arch_counter_get_cntpct;
- 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.
- */
- if (static_branch_unlikely(&arch_timer_read_ool_enabled))
- clocksource_counter.archdata.vdso_direct = false;
-#endif
+ clocksource_counter.archdata.vdso_direct = vdso_default;
} else {
arch_timer_read_counter = arch_counter_get_cntvct_mem;
}
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
+ /* Check for globally applicable workarounds */
+ arch_timer_check_ool_workaround(ate_match_dt, np);
+ arch_timer_check_ool_workaround(ate_match_global_cap_id, NULL);
/*
* If we cannot rely on firmware initializing the timer registers then
/* Always-on capability */
arch_timer_c3stop = !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON);
+ /* Check for globally applicable workarounds */
+ arch_timer_check_ool_workaround(ate_match_global_cap_id, NULL);
+ arch_timer_check_ool_workaround(ate_match_acpi_oem_info, table);
+
arch_timer_init();
return 0;
}
projects / mirror_ubuntu-zesty-kernel.git / blobdiff