*/
#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)
+/*
+ * 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)
{
- int ret;
- bool val;
+ return __fsl_a008585_read_reg(cntp_tval_el0);
+}
- ret = strtobool(buf, &val);
- if (ret)
- return ret;
+static u32 notrace fsl_a008585_read_cntv_tval_el0(void)
+{
+ return __fsl_a008585_read_reg(cntv_tval_el0);
+}
- fsl_a008585_enable = val;
- return 0;
+static u64 notrace fsl_a008585_read_cntvct_el0(void)
+{
+ return __fsl_a008585_read_reg(cntvct_el0);
}
-early_param("clocksource.arm_arch_timer.fsl-a008585", early_fsl_a008585_cfg);
+#endif
-u32 __fsl_a008585_read_cntp_tval_el0(void)
+#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 __fsl_a008585_read_reg(cntp_tval_el0);
+ return __hisi_161010101_read_reg(cntp_tval_el0);
}
-u32 __fsl_a008585_read_cntv_tval_el0(void)
+static u32 notrace hisi_161010101_read_cntv_tval_el0(void)
{
- return __fsl_a008585_read_reg(cntv_tval_el0);
+ return __hisi_161010101_read_reg(cntv_tval_el0);
}
-u64 __fsl_a008585_read_cntvct_el0(void)
+static u64 notrace hisi_161010101_read_cntvct_el0(void)
{
- return __fsl_a008585_read_reg(cntvct_el0);
+ return __hisi_161010101_read_reg(cntvct_el0);
}
-EXPORT_SYMBOL(__fsl_a008585_read_cntvct_el0);
-#endif /* CONFIG_FSL_ERRATUM_A008585 */
+#endif
+
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
+const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround = NULL;
+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 const struct arch_timer_erratum_workaround ool_workarounds[] = {
+#ifdef CONFIG_FSL_ERRATUM_A008585
+ {
+ .id = "fsl,erratum-a008585",
+ .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,
+ },
+#endif
+#ifdef CONFIG_HISILICON_ERRATUM_161010101
+ {
+ .id = "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,
+ },
+#endif
+};
+#endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */
static __always_inline
void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val,
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,
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
+static __always_inline void erratum_set_next_event_generic(const int access,
unsigned long evt, struct clock_event_device *clk)
{
unsigned long ctrl;
arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
}
-static int fsl_a008585_set_next_event_virt(unsigned long evt,
+static int erratum_set_next_event_virt(unsigned long evt,
struct clock_event_device *clk)
{
- fsl_a008585_set_next_event(ARCH_TIMER_VIRT_ACCESS, evt, clk);
+ erratum_set_next_event_generic(ARCH_TIMER_VIRT_ACCESS, evt, clk);
return 0;
}
-static int fsl_a008585_set_next_event_phys(unsigned long evt,
+static int erratum_set_next_event_phys(unsigned long evt,
struct clock_event_device *clk)
{
- fsl_a008585_set_next_event(ARCH_TIMER_PHYS_ACCESS, evt, clk);
+ erratum_set_next_event_generic(ARCH_TIMER_PHYS_ACCESS, evt, clk);
return 0;
}
-#endif /* CONFIG_FSL_ERRATUM_A008585 */
+#endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */
static int arch_timer_set_next_event_virt(unsigned long evt,
struct clock_event_device *clk)
return 0;
}
-static void fsl_a008585_set_sne(struct clock_event_device *clk)
+static void erratum_workaround_set_sne(struct clock_event_device *clk)
{
-#ifdef CONFIG_FSL_ERRATUM_A008585
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
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;
+ clk->set_next_event = erratum_set_next_event_virt;
else
- clk->set_next_event = fsl_a008585_set_next_event_phys;
+ clk->set_next_event = erratum_set_next_event_phys;
#endif
}
BUG();
}
- fsl_a008585_set_sne(clk);
+ erratum_workaround_set_sne(clk);
} else {
clk->features |= CLOCK_EVT_FEAT_DYNIRQ;
clk->name = "arch_mem_timer";
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
-static struct cyclecounter cyclecounter = {
+static struct cyclecounter cyclecounter __ro_after_init = {
.read = arch_counter_read_cc,
.mask = CLOCKSOURCE_MASK(56),
};
clocksource_counter.archdata.vdso_direct = true;
-#ifdef CONFIG_FSL_ERRATUM_A008585
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
/*
* Don't use the vdso fastpath if errata require using
* the out-of-line counter accessor.
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");
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
+ for (i = 0; i < ARRAY_SIZE(ool_workarounds); i++) {
+ if (of_property_read_bool(np, ool_workarounds[i].id)) {
+ timer_unstable_counter_workaround = &ool_workarounds[i];
+ static_branch_enable(&arch_timer_read_ool_enabled);
+ pr_info("arch_timer: Enabling workaround for %s\n",
+ timer_unstable_counter_workaround->id);
+ break;
+ }
}
#endif
projects / mirror_ubuntu-artful-kernel.git / blobdiff