From: Marc Zyngier maz@kernel.org
mainline inclusion from mainline-v5.16-rc1 commit d72689988d67 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I4QCBG CVE: NA
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The arch timer driver never reads the various TVAL registers, only writes to them. It is thus pointless to provide accessors for them and to implement errata workarounds.
Drop these read-side accessors, and add a couple of BUG() statements for the time being. These statements will be removed further down the line.
Reviewed-by: Oliver Upton oupton@google.com Reviewed-by: Mark Rutland mark.rutland@arm.com Tested-by: Mark Rutland mark.rutland@arm.com Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20211017124225.3018098-3-maz@kernel.org Signed-off-by: Daniel Lezcano daniel.lezcano@linaro.org Signed-off-by: Xiongfeng Wang wangxiongfeng2@huawei.com Reviewed-by: Hanjun Guo guohanjun@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- arch/arm/include/asm/arch_timer.h | 6 ---- arch/arm64/include/asm/arch_timer.h | 17 ----------- drivers/clocksource/arm_arch_timer.c | 44 ---------------------------- 3 files changed, 67 deletions(-)
diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h index a5d27cff28fa..7d757085c61a 100644 --- a/arch/arm/include/asm/arch_timer.h +++ b/arch/arm/include/asm/arch_timer.h @@ -65,9 +65,6 @@ u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg) case ARCH_TIMER_REG_CTRL: asm volatile("mrc p15, 0, %0, c14, c2, 1" : "=r" (val)); break; - case ARCH_TIMER_REG_TVAL: - asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val)); - break; default: BUILD_BUG(); } @@ -76,9 +73,6 @@ u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg) case ARCH_TIMER_REG_CTRL: asm volatile("mrc p15, 0, %0, c14, c3, 1" : "=r" (val)); break; - case ARCH_TIMER_REG_TVAL: - asm volatile("mrc p15, 0, %0, c14, c3, 0" : "=r" (val)); - break; default: BUILD_BUG(); } diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h index 7dfb7c6261bb..a57c0fb7ab02 100644 --- a/arch/arm64/include/asm/arch_timer.h +++ b/arch/arm64/include/asm/arch_timer.h @@ -52,8 +52,6 @@ struct arch_timer_erratum_workaround { enum arch_timer_erratum_match_type match_type; const void *id; const char *desc; - u32 (*read_cntp_tval_el0)(void); - u32 (*read_cntv_tval_el0)(void); u64 (*read_cntpct_el0)(void); u64 (*read_cntvct_el0)(void); int (*set_next_event_phys)(unsigned long, struct clock_event_device *); @@ -64,17 +62,6 @@ struct arch_timer_erratum_workaround { DECLARE_PER_CPU(const struct arch_timer_erratum_workaround *, timer_unstable_counter_workaround);
-/* inline sysreg accessors that make erratum_handler() work */ -static inline notrace u32 arch_timer_read_cntp_tval_el0(void) -{ - return read_sysreg(cntp_tval_el0); -} - -static inline notrace u32 arch_timer_read_cntv_tval_el0(void) -{ - return read_sysreg(cntv_tval_el0); -} - static inline notrace u64 arch_timer_read_cntpct_el0(void) { return read_sysreg(cntpct_el0); @@ -140,8 +127,6 @@ u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg) switch (reg) { case ARCH_TIMER_REG_CTRL: return read_sysreg(cntp_ctl_el0); - case ARCH_TIMER_REG_TVAL: - return arch_timer_reg_read_stable(cntp_tval_el0); default: BUILD_BUG(); } @@ -149,8 +134,6 @@ u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg) switch (reg) { case ARCH_TIMER_REG_CTRL: return read_sysreg(cntv_ctl_el0); - case ARCH_TIMER_REG_TVAL: - return arch_timer_reg_read_stable(cntv_tval_el0); default: BUILD_BUG(); } diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index f3c65e5181ec..b481596ef3cd 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -135,9 +135,6 @@ u32 arch_timer_reg_read(int access, enum arch_timer_reg reg, case ARCH_TIMER_REG_CTRL: val = readl_relaxed(timer->base + CNTP_CTL); break; - case ARCH_TIMER_REG_TVAL: - val = readl_relaxed(timer->base + CNTP_TVAL); - break; default: BUILD_BUG(); } @@ -147,9 +144,6 @@ u32 arch_timer_reg_read(int access, enum arch_timer_reg reg, case ARCH_TIMER_REG_CTRL: val = readl_relaxed(timer->base + CNTV_CTL); break; - case ARCH_TIMER_REG_TVAL: - val = readl_relaxed(timer->base + CNTV_TVAL); - break; default: BUILD_BUG(); } @@ -237,16 +231,6 @@ struct ate_acpi_oem_info { _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_cntpct_el0(void) { return __fsl_a008585_read_reg(cntpct_el0); @@ -283,16 +267,6 @@ static u64 notrace fsl_a008585_read_cntvct_el0(void) _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_cntpct_el0(void) { return __hisi_161010101_read_reg(cntpct_el0); @@ -377,16 +351,6 @@ static u64 notrace sun50i_a64_read_cntvct_el0(void) { return __sun50i_a64_read_reg(cntvct_el0); } - -static u32 notrace sun50i_a64_read_cntp_tval_el0(void) -{ - return read_sysreg(cntp_cval_el0) - sun50i_a64_read_cntpct_el0(); -} - -static u32 notrace sun50i_a64_read_cntv_tval_el0(void) -{ - return read_sysreg(cntv_cval_el0) - sun50i_a64_read_cntvct_el0(); -} #endif
#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND @@ -436,8 +400,6 @@ static const struct arch_timer_erratum_workaround ool_workarounds[] = { .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_cntpct_el0 = fsl_a008585_read_cntpct_el0, .read_cntvct_el0 = fsl_a008585_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_tval_phys, @@ -449,8 +411,6 @@ static const struct arch_timer_erratum_workaround ool_workarounds[] = { .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_cntpct_el0 = hisi_161010101_read_cntpct_el0, .read_cntvct_el0 = hisi_161010101_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_tval_phys, @@ -460,8 +420,6 @@ static const struct arch_timer_erratum_workaround ool_workarounds[] = { .match_type = ate_match_acpi_oem_info, .id = hisi_161010101_oem_info, .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_cntpct_el0 = hisi_161010101_read_cntpct_el0, .read_cntvct_el0 = hisi_161010101_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_tval_phys, @@ -482,8 +440,6 @@ static const struct arch_timer_erratum_workaround ool_workarounds[] = { .match_type = ate_match_dt, .id = "allwinner,erratum-unknown1", .desc = "Allwinner erratum UNKNOWN1", - .read_cntp_tval_el0 = sun50i_a64_read_cntp_tval_el0, - .read_cntv_tval_el0 = sun50i_a64_read_cntv_tval_el0, .read_cntpct_el0 = sun50i_a64_read_cntpct_el0, .read_cntvct_el0 = sun50i_a64_read_cntvct_el0, .set_next_event_phys = erratum_set_next_event_tval_phys,