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authorLinus Torvalds <torvalds@linux-foundation.org>2016-10-03 08:58:35 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-10-03 08:58:35 -0700
commit7af8a0f8088831428051976cb06cc1e450f8bab5 (patch)
tree45289becbd10b1e421dc4b5a99ce6d7d90964c28 /drivers/clocksource
parentc8d2bc9bc39ebea8437fd974fdbc21847bb897a3 (diff)
parentdb68f3e7594aca77632d56c449bd36c6c931d59a (diff)
downloadlinux-0-day-7af8a0f8088831428051976cb06cc1e450f8bab5.tar.gz
linux-0-day-7af8a0f8088831428051976cb06cc1e450f8bab5.tar.xz
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon: "It's a bit all over the place this time with no "killer feature" to speak of. Support for mismatched cache line sizes should help people seeing whacky JIT failures on some SoCs, and the big.LITTLE perf updates have been a long time coming, but a lot of the changes here are cleanups. We stray outside arch/arm64 in a few areas: the arch/arm/ arch_timer workaround is acked by Russell, the DT/OF bits are acked by Rob, the arch_timer clocksource changes acked by Marc, CPU hotplug by tglx and jump_label by Peter (all CC'd). Summary: - Support for execute-only page permissions - Support for hibernate and DEBUG_PAGEALLOC - Support for heterogeneous systems with mismatches cache line sizes - Errata workarounds (A53 843419 update and QorIQ A-008585 timer bug) - arm64 PMU perf updates, including cpumasks for heterogeneous systems - Set UTS_MACHINE for building rpm packages - Yet another head.S tidy-up - Some cleanups and refactoring, particularly in the NUMA code - Lots of random, non-critical fixes across the board" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (100 commits) arm64: tlbflush.h: add __tlbi() macro arm64: Kconfig: remove SMP dependence for NUMA arm64: Kconfig: select OF/ACPI_NUMA under NUMA config arm64: fix dump_backtrace/unwind_frame with NULL tsk arm/arm64: arch_timer: Use archdata to indicate vdso suitability arm64: arch_timer: Work around QorIQ Erratum A-008585 arm64: arch_timer: Add device tree binding for A-008585 erratum arm64: Correctly bounds check virt_addr_valid arm64: migrate exception table users off module.h and onto extable.h arm64: pmu: Hoist pmu platform device name arm64: pmu: Probe default hw/cache counters arm64: pmu: add fallback probe table MAINTAINERS: Update ARM PMU PROFILING AND DEBUGGING entry arm64: Improve kprobes test for atomic sequence arm64/kvm: use alternative auto-nop arm64: use alternative auto-nop arm64: alternative: add auto-nop infrastructure arm64: lse: convert lse alternatives NOP padding to use __nops arm64: barriers: introduce nops and __nops macros for NOP sequences arm64: sysreg: replace open-coded mrs_s/msr_s with {read,write}_sysreg_s ...
Diffstat (limited to 'drivers/clocksource')
-rw-r--r--drivers/clocksource/Kconfig10
-rw-r--r--drivers/clocksource/arm_arch_timer.c113
2 files changed, 116 insertions, 7 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 567788664723d..8a753fd5b79d5 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -305,6 +305,16 @@ config ARM_ARCH_TIMER_EVTSTREAM
This must be disabled for hardware validation purposes to detect any
hardware anomalies of missing events.
+config FSL_ERRATUM_A008585
+ bool "Workaround for Freescale/NXP Erratum A-008585"
+ default y
+ depends on ARM_ARCH_TIMER && ARM64
+ help
+ This option enables a workaround for Freescale/NXP Erratum
+ A-008585 ("ARM generic timer may contain an erroneous
+ value"). The workaround will only be active if the
+ fsl,erratum-a008585 property is found in the timer node.
+
config ARM_GLOBAL_TIMER
bool "Support for the ARM global timer" if COMPILE_TEST
select CLKSRC_OF if OF
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 57700541f9512..73c487da6d2a9 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -94,6 +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)
@@ -243,6 +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)
{
@@ -271,6 +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)
{
@@ -299,6 +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";
@@ -515,15 +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();
@@ -800,6 +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.