[PATCH v2 5/5] ARM: convert asm/irqflags.h to use asm-generic/irqflags.h

Rob Herring
2012-08-05T01:24:00Z

From: Rob Herring <rob.herring@calxeda.com>

By implmenting arch_local_irq_restore with constant flags, we can use
asm-generic/irqflags.h and remove some of the ARM version of irqflags.h.

Verified the code is equivalent by checking the disassembled code.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
---
arch/arm/include/asm/irqflags.h | 131 ++++++++++++++-------------------------
1 file changed, 45 insertions(+), 86 deletions(-)

diff --git a/arch/arm/include/asm/irqflags.h b/arch/arm/include/asm/irqflags.h
index 1e6cca5..67bfb53 100644
--- a/arch/arm/include/asm/irqflags.h
+++ b/arch/arm/include/asm/irqflags.h
@@ -8,88 +8,68 @@
/*
* CPU interrupt mask handling.
*/
-#if __LINUX_ARM_ARCH__ >= 6
+#define ARCH_IRQ_DISABLED PSR_I_BIT
+#define ARCH_IRQ_ENABLED 0

-static inline unsigned long arch_local_irq_save(void)
+static inline unsigned long arch_local_save_flags(void)
{
unsigned long flags;

asm volatile(
- " mrs %0, cpsr @ arch_local_irq_save\n"
- " cpsid i"
+ " mrs %0, cpsr @ arch_local_save_flags\n"
: "=r" (flags) : : "memory", "cc");
return flags;
}

-static inline void arch_local_irq_enable(void)
+static inline void constant_arch_local_irq_restore(unsigned long flags)
{
- asm volatile(
- " cpsie i @ arch_local_irq_enable"
- :
- :
- : "memory", "cc");
+#if __LINUX_ARM_ARCH__ >= 6
+ if (flags == ARCH_IRQ_ENABLED)
+ asm volatile(
+ " cpsie i @ constant_arch_local_irq_restore"
+ : : : "memory", "cc");
+ else if (flags == ARCH_IRQ_DISABLED)
+ asm volatile(
+ " cpsid i @ constant_arch_local_irq_restore"
+ : : : "memory", "cc");
+#else
+ unsigned long temp;
+ if (flags == ARCH_IRQ_ENABLED)
+ asm volatile(
+ " mrs %0, cpsr @ constant_arch_local_irq_restore\n"
+ " bic %0, %0, #128\n"
+ " msr cpsr_c, %0"
+ : "=r" (temp)
+ :
+ : "memory", "cc");
+ else if (flags == ARCH_IRQ_DISABLED)
+ asm volatile(
+ " mrs %0, cpsr @ constant_arch_local_irq_restore\n"
+ " orr %0, %0, #128\n"
+ " msr cpsr_c, %0"
+ : "=r" (temp)
+ :
+ : "memory", "cc");
+#endif
}

-static inline void arch_local_irq_disable(void)
+static inline void _arch_local_irq_restore(unsigned long flags)
{
- asm volatile(
- " cpsid i @ arch_local_irq_disable"
- :
+ asm volatile(
+ " msr cpsr_c, %0 @ _arch_local_irq_restore"
:
+ : "r" (flags)
: "memory", "cc");
}

+#define arch_local_irq_restore(flags) \
+ (__builtin_constant_p(flags) ? constant_arch_local_irq_restore(flags) : \
+ _arch_local_irq_restore(flags))
+
+#if __LINUX_ARM_ARCH__ >= 6
#define local_fiq_enable() __asm__("cpsie f @ __stf" : : : "memory", "cc")
#define local_fiq_disable() __asm__("cpsid f @ __clf" : : : "memory", "cc")
#else
-
-/*
- * Save the current interrupt enable state & disable IRQs
- */
-static inline unsigned long arch_local_irq_save(void)
-{
- unsigned long flags, temp;
-
- asm volatile(
- " mrs %0, cpsr @ arch_local_irq_save\n"
- " orr %1, %0, #128\n"
- " msr cpsr_c, %1"
- : "=r" (flags), "=r" (temp)
- :
- : "memory", "cc");
- return flags;
-}
-
-/*
- * Enable IRQs
- */
-static inline void arch_local_irq_enable(void)
-{
- unsigned long temp;
- asm volatile(
- " mrs %0, cpsr @ arch_local_irq_enable\n"
- " bic %0, %0, #128\n"
- " msr cpsr_c, %0"
- : "=r" (temp)
- :
- : "memory", "cc");
-}
-
-/*
- * Disable IRQs
- */
-static inline void arch_local_irq_disable(void)
-{
- unsigned long temp;
- asm volatile(
- " mrs %0, cpsr @ arch_local_irq_disable\n"
- " orr %0, %0, #128\n"
- " msr cpsr_c, %0"
- : "=r" (temp)
- :
- : "memory", "cc");
-}
-
/*
* Enable FIQs
*/
@@ -122,34 +102,13 @@ static inline void arch_local_irq_disable(void)

#endif

-/*
- * Save the current interrupt enable state.
- */
-static inline unsigned long arch_local_save_flags(void)
-{
- unsigned long flags;
- asm volatile(
- " mrs %0, cpsr @ local_save_flags"
- : "=r" (flags) : : "memory", "cc");
- return flags;
-}
-
-/*
- * restore saved IRQ & FIQ state
- */
-static inline void arch_local_irq_restore(unsigned long flags)
-{
- asm volatile(
- " msr cpsr_c, %0 @ local_irq_restore"
- :
- : "r" (flags)
- : "memory", "cc");
-}
-
static inline int arch_irqs_disabled_flags(unsigned long flags)
{
return flags & PSR_I_BIT;
}
+#define arch_irqs_disabled_flags arch_irqs_disabled_flags
+
+#include <asm-generic/irqflags.h>

#endif
#endif
--
1.7.9.5