| Message ID | 1484824474-12172-3-git-send-email-dingtianhong@huawei.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | arm64: arch_timer: Add workaround for hisilicon-161601 erratum | expand |
On 19/01/17 11:14, Ding Tianhong wrote: > The workaround for hisilicon,161010101 will check the return value of the system counter > by different way, in order to distinguish with the fsl-a008585 workaround, introduce > a new generic erratum handing mechanism for fsl-a008585 and rename some functions. > > After discussion with Marc and Will, a consensus decision was made to remove the commandline > parameter for enabling fsl,erratum-a008585 erratum. > > Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> > --- > Documentation/admin-guide/kernel-parameters.txt | 9 -- > arch/arm64/include/asm/arch_timer.h | 38 +++------ > drivers/clocksource/Kconfig | 8 ++ > drivers/clocksource/arm_arch_timer.c | 105 ++++++++++++++---------- > 4 files changed, 84 insertions(+), 76 deletions(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 21e2d88..76437ad 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -539,15 +539,6 @@ > loops can be debugged more effectively on production > systems. > > - clocksource.arm_arch_timer.fsl-a008585= > - [ARM64] > - Format: <bool> > - Enable/disable the workaround of Freescale/NXP > - erratum A-008585. This can be useful for KVM > - guests, if the guest device tree doesn't show the > - erratum. If unspecified, the workaround is > - enabled based on the device tree. > - > clearcpuid=BITNUM [X86] > Disable CPUID feature X for the kernel. See > arch/x86/include/asm/cpufeatures.h for the valid bit > diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h > index eaa5bbe..b4b3400 100644 > --- a/arch/arm64/include/asm/arch_timer.h > +++ b/arch/arm64/include/asm/arch_timer.h > @@ -29,41 +29,29 @@ > > #include <clocksource/arm_arch_timer.h> > > -#if IS_ENABLED(CONFIG_FSL_ERRATUM_A008585) > +#if IS_ENABLED(CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND) > extern struct static_key_false arch_timer_read_ool_enabled; > -#define needs_fsl_a008585_workaround() \ > +#define needs_unstable_timer_counter_workaround() \ > static_branch_unlikely(&arch_timer_read_ool_enabled) > #else > -#define needs_fsl_a008585_workaround() false > +#define needs_unstable_timer_counter_workaround() false > #endif > > -u32 __fsl_a008585_read_cntp_tval_el0(void); > -u32 __fsl_a008585_read_cntv_tval_el0(void); > -u64 __fsl_a008585_read_cntvct_el0(void); > > -/* > - * 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; \ > -}) > +struct arch_timer_erratum_workaround { > + const char *id; /* Indicate the Erratum ID */ > + u32 (*read_cntp_tval_el0)(void); > + u32 (*read_cntv_tval_el0)(void); > + u64 (*read_cntvct_el0)(void); > +}; > + > +extern const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround; > > #define arch_timer_reg_read_stable(reg) \ > ({ \ > u64 _val; \ > - if (needs_fsl_a008585_workaround()) \ > - _val = __fsl_a008585_read_##reg(); \ > + if (needs_unstable_timer_counter_workaround()) \ > + _val = timer_unstable_counter_workaround->read_##reg();\ > else \ > _val = read_sysreg(reg); \ > _val; \ > diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig > index 4866f7a..04c2b93 100644 > --- a/drivers/clocksource/Kconfig > +++ b/drivers/clocksource/Kconfig > @@ -325,10 +325,18 @@ config ARM_ARCH_TIMER_EVTSTREAM > This must be disabled for hardware validation purposes to detect any > hardware anomalies of missing events. > > +config ARM_ARCH_TIMER_OOL_WORKAROUND > + bool "Workaround for arm arch timer unstable counter" Please drop the message. We don't want that option to be selectable by a user, but only selected if an erratum that depends on it is enabled. > + depends on FSL_ERRATUM_A008585 > + help > + This option would only be enabled by Freescale/NXP Erratum A-008585 > + or something else chip has similar erratum. > + > config FSL_ERRATUM_A008585 > bool "Workaround for Freescale/NXP Erratum A-008585" > default y > depends on ARM_ARCH_TIMER && ARM64 > + select ARM_ARCH_TIMER_OOL_WORKAROUND > help > This option enables a workaround for Freescale/NXP Erratum > A-008585 ("ARM generic timer may contain an erroneous Thanks, M. -- Jazz is not dead. It just smells funny... _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On 2017/1/19 19:59, Marc Zyngier wrote: > On 19/01/17 11:14, Ding Tianhong wrote: >> The workaround for hisilicon,161010101 will check the return value of the system counter >> by different way, in order to distinguish with the fsl-a008585 workaround, introduce >> a new generic erratum handing mechanism for fsl-a008585 and rename some functions. >> >> After discussion with Marc and Will, a consensus decision was made to remove the commandline >> parameter for enabling fsl,erratum-a008585 erratum. >> >> Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> >> --- >> Documentation/admin-guide/kernel-parameters.txt | 9 -- >> arch/arm64/include/asm/arch_timer.h | 38 +++------ >> drivers/clocksource/Kconfig | 8 ++ >> drivers/clocksource/arm_arch_timer.c | 105 ++++++++++++++---------- >> 4 files changed, 84 insertions(+), 76 deletions(-) >> >> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt >> index 21e2d88..76437ad 100644 >> --- a/Documentation/admin-guide/kernel-parameters.txt >> +++ b/Documentation/admin-guide/kernel-parameters.txt >> @@ -539,15 +539,6 @@ >> loops can be debugged more effectively on production >> systems. >> >> - clocksource.arm_arch_timer.fsl-a008585= >> - [ARM64] >> - Format: <bool> >> - Enable/disable the workaround of Freescale/NXP >> - erratum A-008585. This can be useful for KVM >> - guests, if the guest device tree doesn't show the >> - erratum. If unspecified, the workaround is >> - enabled based on the device tree. >> - >> clearcpuid=BITNUM [X86] >> Disable CPUID feature X for the kernel. See >> arch/x86/include/asm/cpufeatures.h for the valid bit >> diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h >> index eaa5bbe..b4b3400 100644 >> --- a/arch/arm64/include/asm/arch_timer.h >> +++ b/arch/arm64/include/asm/arch_timer.h >> @@ -29,41 +29,29 @@ >> >> #include <clocksource/arm_arch_timer.h> >> >> -#if IS_ENABLED(CONFIG_FSL_ERRATUM_A008585) >> +#if IS_ENABLED(CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND) >> extern struct static_key_false arch_timer_read_ool_enabled; >> -#define needs_fsl_a008585_workaround() \ >> +#define needs_unstable_timer_counter_workaround() \ >> static_branch_unlikely(&arch_timer_read_ool_enabled) >> #else >> -#define needs_fsl_a008585_workaround() false >> +#define needs_unstable_timer_counter_workaround() false >> #endif >> >> -u32 __fsl_a008585_read_cntp_tval_el0(void); >> -u32 __fsl_a008585_read_cntv_tval_el0(void); >> -u64 __fsl_a008585_read_cntvct_el0(void); >> >> -/* >> - * 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; \ >> -}) >> +struct arch_timer_erratum_workaround { >> + const char *id; /* Indicate the Erratum ID */ >> + u32 (*read_cntp_tval_el0)(void); >> + u32 (*read_cntv_tval_el0)(void); >> + u64 (*read_cntvct_el0)(void); >> +}; >> + >> +extern const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround; >> >> #define arch_timer_reg_read_stable(reg) \ >> ({ \ >> u64 _val; \ >> - if (needs_fsl_a008585_workaround()) \ >> - _val = __fsl_a008585_read_##reg(); \ >> + if (needs_unstable_timer_counter_workaround()) \ >> + _val = timer_unstable_counter_workaround->read_##reg();\ >> else \ >> _val = read_sysreg(reg); \ >> _val; \ >> diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig >> index 4866f7a..04c2b93 100644 >> --- a/drivers/clocksource/Kconfig >> +++ b/drivers/clocksource/Kconfig >> @@ -325,10 +325,18 @@ config ARM_ARCH_TIMER_EVTSTREAM >> This must be disabled for hardware validation purposes to detect any >> hardware anomalies of missing events. >> >> +config ARM_ARCH_TIMER_OOL_WORKAROUND >> + bool "Workaround for arm arch timer unstable counter" > > Please drop the message. We don't want that option to be selectable by a > user, but only selected if an erratum that depends on it is enabled. > OK Thanks Ding >> + depends on FSL_ERRATUM_A008585 >> + help >> + This option would only be enabled by Freescale/NXP Erratum A-008585 >> + or something else chip has similar erratum. >> + >> config FSL_ERRATUM_A008585 >> bool "Workaround for Freescale/NXP Erratum A-008585" >> default y >> depends on ARM_ARCH_TIMER && ARM64 >> + select ARM_ARCH_TIMER_OOL_WORKAROUND >> help >> This option enables a workaround for Freescale/NXP Erratum >> A-008585 ("ARM generic timer may contain an erroneous > > Thanks, > > M. > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 21e2d88..76437ad 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -539,15 +539,6 @@ loops can be debugged more effectively on production systems. - clocksource.arm_arch_timer.fsl-a008585= - [ARM64] - Format: <bool> - Enable/disable the workaround of Freescale/NXP - erratum A-008585. This can be useful for KVM - guests, if the guest device tree doesn't show the - erratum. If unspecified, the workaround is - enabled based on the device tree. - clearcpuid=BITNUM [X86] Disable CPUID feature X for the kernel. See arch/x86/include/asm/cpufeatures.h for the valid bit diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h index eaa5bbe..b4b3400 100644 --- a/arch/arm64/include/asm/arch_timer.h +++ b/arch/arm64/include/asm/arch_timer.h @@ -29,41 +29,29 @@ #include <clocksource/arm_arch_timer.h> -#if IS_ENABLED(CONFIG_FSL_ERRATUM_A008585) +#if IS_ENABLED(CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND) extern struct static_key_false arch_timer_read_ool_enabled; -#define needs_fsl_a008585_workaround() \ +#define needs_unstable_timer_counter_workaround() \ static_branch_unlikely(&arch_timer_read_ool_enabled) #else -#define needs_fsl_a008585_workaround() false +#define needs_unstable_timer_counter_workaround() false #endif -u32 __fsl_a008585_read_cntp_tval_el0(void); -u32 __fsl_a008585_read_cntv_tval_el0(void); -u64 __fsl_a008585_read_cntvct_el0(void); -/* - * 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; \ -}) +struct arch_timer_erratum_workaround { + const char *id; /* Indicate the Erratum ID */ + u32 (*read_cntp_tval_el0)(void); + u32 (*read_cntv_tval_el0)(void); + u64 (*read_cntvct_el0)(void); +}; + +extern const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround; #define arch_timer_reg_read_stable(reg) \ ({ \ u64 _val; \ - if (needs_fsl_a008585_workaround()) \ - _val = __fsl_a008585_read_##reg(); \ + if (needs_unstable_timer_counter_workaround()) \ + _val = timer_unstable_counter_workaround->read_##reg();\ else \ _val = read_sysreg(reg); \ _val; \ diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 4866f7a..04c2b93 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -325,10 +325,18 @@ config ARM_ARCH_TIMER_EVTSTREAM This must be disabled for hardware validation purposes to detect any hardware anomalies of missing events. +config ARM_ARCH_TIMER_OOL_WORKAROUND + bool "Workaround for arm arch timer unstable counter" + depends on FSL_ERRATUM_A008585 + help + This option would only be enabled by Freescale/NXP Erratum A-008585 + or something else chip has similar erratum. + config FSL_ERRATUM_A008585 bool "Workaround for Freescale/NXP Erratum A-008585" default y depends on ARM_ARCH_TIMER && ARM64 + select ARM_ARCH_TIMER_OOL_WORKAROUND help This option enables a workaround for Freescale/NXP Erratum A-008585 ("ARM generic timer may contain an erroneous diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 02fef68..2487c66 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -96,41 +96,59 @@ static int __init early_evtstrm_cfg(char *buf) */ #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) +/* + * 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); } -u32 __fsl_a008585_read_cntv_tval_el0(void) +static u32 notrace fsl_a008585_read_cntv_tval_el0(void) { return __fsl_a008585_read_reg(cntv_tval_el0); } -u64 __fsl_a008585_read_cntvct_el0(void) +static u64 notrace 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 */ +#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 +}; +#endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */ static __always_inline void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val, @@ -281,8 +299,8 @@ 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, +#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; @@ -300,20 +318,20 @@ static __always_inline void fsl_a008585_set_next_event(const int access, 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) @@ -343,16 +361,16 @@ 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) +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 } @@ -385,7 +403,7 @@ static void __arch_timer_setup(unsigned type, BUG(); } - fsl_a008585_set_sne(clk); + erratum_workaround_set_sne(clk); } else { clk->features |= CLOCK_EVT_FEAT_DYNIRQ; clk->name = "arch_mem_timer"; @@ -605,7 +623,7 @@ static void __init arch_counter_register(unsigned type) 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. @@ -893,12 +911,15 @@ 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"); +#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
The workaround for hisilicon,161010101 will check the return value of the system counter by different way, in order to distinguish with the fsl-a008585 workaround, introduce a new generic erratum handing mechanism for fsl-a008585 and rename some functions. After discussion with Marc and Will, a consensus decision was made to remove the commandline parameter for enabling fsl,erratum-a008585 erratum. Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> --- Documentation/admin-guide/kernel-parameters.txt | 9 -- arch/arm64/include/asm/arch_timer.h | 38 +++------ drivers/clocksource/Kconfig | 8 ++ drivers/clocksource/arm_arch_timer.c | 105 ++++++++++++++---------- 4 files changed, 84 insertions(+), 76 deletions(-) -- 1.9.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel