[PATCH 1/2] arm: Move sev() and wfe() definitions to common Arm header file
Peter Hoyes
peter.hoyes at arm.com
Tue Apr 23 10:10:04 CEST 2024
From: Peter Hoyes <Peter.Hoyes at arm.com>
The sev() and wfe() asm macros are currently defined only for
mach-exynos. As these are common Arm instructions, move them to the
common asm/system.h header file, for both Armv7 and Armv8, so they
can be used by other machines.
wfe may theoretically trigger a context switch if an interrupt occurs
so add a memory barrier to this call.
Signed-off-by: Peter Hoyes <Peter.Hoyes at arm.com>
---
arch/arm/include/asm/system.h | 9 +++++++++
arch/arm/mach-exynos/include/mach/system.h | 19 -------------------
2 files changed, 9 insertions(+), 19 deletions(-)
diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h
index 43f7503571..51123c2968 100644
--- a/arch/arm/include/asm/system.h
+++ b/arch/arm/include/asm/system.h
@@ -154,6 +154,13 @@ enum dcache_option {
"wfi" : : : "memory"); \
})
+#define wfe() \
+ ({asm volatile( \
+ "wfe" : : : "memory"); \
+ })
+
+#define sev() asm volatile("sev")
+
static inline unsigned int current_el(void)
{
unsigned long el;
@@ -369,6 +376,8 @@ void switch_to_hypervisor_ret(void);
#ifdef __ARM_ARCH_7A__
#define wfi() __asm__ __volatile__ ("wfi" : : : "memory")
+#define wfe() __asm__ __volatile__ ("wfe" : : : "memory")
+#define sev() __asm__ __volatile__ ("sev")
#else
#define wfi()
#endif
diff --git a/arch/arm/mach-exynos/include/mach/system.h b/arch/arm/mach-exynos/include/mach/system.h
index 5d0bebac57..0aed4c3e2b 100644
--- a/arch/arm/mach-exynos/include/mach/system.h
+++ b/arch/arm/mach-exynos/include/mach/system.h
@@ -36,25 +36,6 @@ struct exynos5_sysreg {
#define USB20_PHY_CFG_HOST_LINK_EN (1 << 0)
-/*
- * This instruction causes an event to be signaled to all cores
- * within a multiprocessor system. If SEV is implemented,
- * WFE must also be implemented.
- */
-#define sev() __asm__ __volatile__ ("sev\n\t" : : );
-/*
- * If the Event Register is not set, WFE suspends execution until
- * one of the following events occurs:
- * - an IRQ interrupt, unless masked by the CPSR I-bit
- * - an FIQ interrupt, unless masked by the CPSR F-bit
- * - an Imprecise Data abort, unless masked by the CPSR A-bit
- * - a Debug Entry request, if Debug is enabled
- * - an Event signaled by another processor using the SEV instruction.
- * If the Event Register is set, WFE clears it and returns immediately.
- * If WFE is implemented, SEV must also be implemented.
- */
-#define wfe() __asm__ __volatile__ ("wfe\n\t" : : );
-
/* Move 0xd3 value to CPSR register to enable SVC mode */
#define svc32_mode_en() __asm__ __volatile__ \
("@ I&F disable, Mode: 0x13 - SVC\n\t" \
--
2.34.1
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