On 27/10/16 08:34, Ding Tianhong wrote: > The workaround for hisilicon,161601 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. > > v2: Introducing a new generic erratum handling mechanism for fsl erratum a008585. > > Signed-off-by: Ding Tianhong <dingtianhong@xxxxxxxxxx> > --- > arch/arm64/include/asm/arch_timer.h | 20 +++++++++----- > drivers/clocksource/arm_arch_timer.c | 51 +++++++++++++++++++++--------------- > 2 files changed, 43 insertions(+), 28 deletions(-) > > diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h > index eaa5bbe..118719d8 100644 > --- a/arch/arm64/include/asm/arch_timer.h > +++ b/arch/arm64/include/asm/arch_timer.h > @@ -31,15 +31,21 @@ > > #if IS_ENABLED(CONFIG_FSL_ERRATUM_A008585) > extern struct static_key_false arch_timer_read_ool_enabled; > -#define needs_fsl_a008585_workaround() \ > +#define needs_timer_erratum_workaround() \ > static_branch_unlikely(&arch_timer_read_ool_enabled) This is too generic a name. Please make it more specific. > #else > -#define needs_fsl_a008585_workaround() false > +#define needs_timer_erratum_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); > + > +struct arch_timer_erratum_workaround { > + int erratum; What is the use of this field? > + u32 (*read_cntp_tval_el0)(void); > + u32 (*read_cntv_tval_el0)(void); > + u64 (*read_cntvct_el0)(void); > +}; > + > +extern struct arch_timer_erratum_workaround *erratum_workaround; This is a very generic name for something that has a global visibility. Please choose a more specific variable name. > > /* > * The number of retries is an arbitrary value well beyond the highest number > @@ -62,8 +68,8 @@ u64 __fsl_a008585_read_cntvct_el0(void); > #define arch_timer_reg_read_stable(reg) \ > ({ \ > u64 _val; \ > - if (needs_fsl_a008585_workaround()) \ > - _val = __fsl_a008585_read_##reg(); \ > + if (needs_timer_erratum_workaround()) \ > + _val = erratum_workaround->read_##reg(); \ As mentioned in my initial review, you've now broken modular access to any of the registers. Please fix it. > else \ > _val = read_sysreg(reg); \ > _val; \ > diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c > index 73c487d..e4f7fa1 100644 > --- a/drivers/clocksource/arm_arch_timer.c > +++ b/drivers/clocksource/arm_arch_timer.c > @@ -95,10 +95,32 @@ early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg); > */ > > #ifdef CONFIG_FSL_ERRATUM_A008585 > +struct arch_timer_erratum_workaround *erratum_workaround = NULL; > + > DEFINE_STATIC_KEY_FALSE(arch_timer_read_ool_enabled); > EXPORT_SYMBOL_GPL(arch_timer_read_ool_enabled); > > -static int fsl_a008585_enable = -1; > + > +static u32 fsl_a008585_read_cntp_tval_el0(void) > +{ > + return __fsl_a008585_read_reg(cntp_tval_el0); > +} > + > +static u32 fsl_a008585_read_cntv_tval_el0(void) > +{ > + return __fsl_a008585_read_reg(cntv_tval_el0); > +} > + > +static u64 fsl_a008585_read_cntvct_el0(void) > +{ > + return __fsl_a008585_read_reg(cntvct_el0); > +} So now that you've indirected all calls through a set of pointers, why do you keep the __fsl_a008585_read_reg() macro inside the include file? I don't think it has any purpose in being globally visible now. > + > +static struct arch_timer_erratum_workaround arch_timer_fsl_a008585 = { And here's the proof that the erratum field is useless. > + .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, > +}; > > static int __init early_fsl_a008585_cfg(char *buf) > { > @@ -109,26 +131,12 @@ static int __init early_fsl_a008585_cfg(char *buf) > if (ret) > return ret; > > - fsl_a008585_enable = val; > + if (val) > + erratum_workaround = &arch_timer_fsl_a008585; > + > 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 > @@ -891,9 +899,10 @@ 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) { > + if (!erratum_workaround && of_property_read_bool(np, "fsl,erratum-a008585")) > + erratum_workaround = &arch_timer_fsl_a008585; It used to be possible to disable the erratum workaround on the command line, and you've just removed that feature. Please restore it. > + > + if (erratum_workaround) { > static_branch_enable(&arch_timer_read_ool_enabled); > pr_info("Enabling workaround for FSL erratum A-008585\n"); > } > Thanks, M. -- Jazz is not dead. It just smells funny... -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html