[PATCH 02/13] clocksource/arm_arch_timer: Extend write side of timer register accessors to u64

Marc Zyngier maz at kernel.org
Mon Aug 9 08:26:40 PDT 2021


The various accessors for the timer sysreg and MMIO registers are
currently hardwired to 32bit. However, we are about to introduce
the use of the CVAL registers, which require a 64bit access.

Upgrade the write side of the accessors to take a 64bit value
(the read side is left untouched as we don't plan to ever read
back any of these registers).

No functional change expected.

Signed-off-by: Marc Zyngier <maz at kernel.org>
---
 arch/arm/include/asm/arch_timer.h    | 10 +++++-----
 arch/arm64/include/asm/arch_timer.h  |  2 +-
 drivers/clocksource/arm_arch_timer.c | 10 +++++-----
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h
index 0c09afaa590d..88075c7f4bfd 100644
--- a/arch/arm/include/asm/arch_timer.h
+++ b/arch/arm/include/asm/arch_timer.h
@@ -24,24 +24,24 @@ int arch_timer_arch_init(void);
  * the code. At least it does so with a recent GCC (4.6.3).
  */
 static __always_inline
-void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u32 val)
+void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u64 val)
 {
 	if (access == ARCH_TIMER_PHYS_ACCESS) {
 		switch (reg) {
 		case ARCH_TIMER_REG_CTRL:
-			asm volatile("mcr p15, 0, %0, c14, c2, 1" : : "r" (val));
+			asm volatile("mcr p15, 0, %0, c14, c2, 1" : : "r" ((u32)val));
 			break;
 		case ARCH_TIMER_REG_TVAL:
-			asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" (val));
+			asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" ((u32)val));
 			break;
 		}
 	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
 		switch (reg) {
 		case ARCH_TIMER_REG_CTRL:
-			asm volatile("mcr p15, 0, %0, c14, c3, 1" : : "r" (val));
+			asm volatile("mcr p15, 0, %0, c14, c3, 1" : : "r" ((u32)val));
 			break;
 		case ARCH_TIMER_REG_TVAL:
-			asm volatile("mcr p15, 0, %0, c14, c3, 0" : : "r" (val));
+			asm volatile("mcr p15, 0, %0, c14, c3, 0" : : "r" ((u32)val));
 			break;
 		}
 	}
diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
index 8e3b2ac60c30..107afb721749 100644
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -89,7 +89,7 @@ static inline notrace u64 arch_timer_read_cntvct_el0(void)
  * the code.
  */
 static __always_inline
-void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u32 val)
+void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u64 val)
 {
 	if (access == ARCH_TIMER_PHYS_ACCESS) {
 		switch (reg) {
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 9db5c16e31e7..0b2bac3ef7ce 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -100,27 +100,27 @@ early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg);
  */
 
 static __always_inline
-void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val,
+void arch_timer_reg_write(int access, enum arch_timer_reg reg, u64 val,
 			  struct clock_event_device *clk)
 {
 	if (access == ARCH_TIMER_MEM_PHYS_ACCESS) {
 		struct arch_timer *timer = to_arch_timer(clk);
 		switch (reg) {
 		case ARCH_TIMER_REG_CTRL:
-			writel_relaxed(val, timer->base + CNTP_CTL);
+			writel_relaxed((u32)val, timer->base + CNTP_CTL);
 			break;
 		case ARCH_TIMER_REG_TVAL:
-			writel_relaxed(val, timer->base + CNTP_TVAL);
+			writel_relaxed((u32)val, timer->base + CNTP_TVAL);
 			break;
 		}
 	} else if (access == ARCH_TIMER_MEM_VIRT_ACCESS) {
 		struct arch_timer *timer = to_arch_timer(clk);
 		switch (reg) {
 		case ARCH_TIMER_REG_CTRL:
-			writel_relaxed(val, timer->base + CNTV_CTL);
+			writel_relaxed((u32)val, timer->base + CNTV_CTL);
 			break;
 		case ARCH_TIMER_REG_TVAL:
-			writel_relaxed(val, timer->base + CNTV_TVAL);
+			writel_relaxed((u32)val, timer->base + CNTV_TVAL);
 			break;
 		}
 	} else {
-- 
2.30.2




More information about the linux-arm-kernel mailing list