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author | Dave Martin <dave.martin@linaro.org> | 2011-05-23 12:22:10 +0100 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-05-26 10:31:06 +0100 |
commit | dc2eb928a1bcf6a48f40c1f2ff21b66bdbf91a3c (patch) | |
tree | 3f877569ca481ad79378ed0e5932006434a1cc1e /arch/arm/kernel/fiq.c | |
parent | 4db70f73e56961b9bcdfd0c36c62847a18b7dbb5 (diff) | |
download | lwn-dc2eb928a1bcf6a48f40c1f2ff21b66bdbf91a3c.tar.gz lwn-dc2eb928a1bcf6a48f40c1f2ff21b66bdbf91a3c.zip |
ARM: 6938/1: fiq: Refactor {get,set}_fiq_regs() for Thumb-2
* To remove the risk of inconvenient register allocation decisions
by the compiler, these functions are separated out as pure
assembler.
* The apcs frame manipulation code is not applicable for Thumb-2
(and also not easily compatible). Since it's not essential to
have a full frame on these leaf assembler functions, the frame
manipulation is removed, in the interests of simplicity.
* Split up ldm/stm instructions to be compatible with Thumb-2,
as well as avoiding instruction forms deprecated on >= ARMv7.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel/fiq.c')
-rw-r--r-- | arch/arm/kernel/fiq.c | 45 |
1 files changed, 2 insertions, 43 deletions
diff --git a/arch/arm/kernel/fiq.c b/arch/arm/kernel/fiq.c index e72dc34eea1c..4c164ece5891 100644 --- a/arch/arm/kernel/fiq.c +++ b/arch/arm/kernel/fiq.c @@ -89,47 +89,6 @@ void set_fiq_handler(void *start, unsigned int length) flush_icache_range(0x1c, 0x1c + length); } -/* - * Taking an interrupt in FIQ mode is death, so both these functions - * disable irqs for the duration. Note - these functions are almost - * entirely coded in assembly. - */ -void __naked set_fiq_regs(struct pt_regs *regs) -{ - register unsigned long tmp; - asm volatile ( - "mov ip, sp\n\ - stmfd sp!, {fp, ip, lr, pc}\n\ - sub fp, ip, #4\n\ - mrs %0, cpsr\n\ - msr cpsr_c, %2 @ select FIQ mode\n\ - mov r0, r0\n\ - ldmia %1, {r8 - r14}\n\ - msr cpsr_c, %0 @ return to SVC mode\n\ - mov r0, r0\n\ - ldmfd sp, {fp, sp, pc}" - : "=&r" (tmp) - : "r" (®s->ARM_r8), "I" (PSR_I_BIT | PSR_F_BIT | FIQ_MODE)); -} - -void __naked get_fiq_regs(struct pt_regs *regs) -{ - register unsigned long tmp; - asm volatile ( - "mov ip, sp\n\ - stmfd sp!, {fp, ip, lr, pc}\n\ - sub fp, ip, #4\n\ - mrs %0, cpsr\n\ - msr cpsr_c, %2 @ select FIQ mode\n\ - mov r0, r0\n\ - stmia %1, {r8 - r14}\n\ - msr cpsr_c, %0 @ return to SVC mode\n\ - mov r0, r0\n\ - ldmfd sp, {fp, sp, pc}" - : "=&r" (tmp) - : "r" (®s->ARM_r8), "I" (PSR_I_BIT | PSR_F_BIT | FIQ_MODE)); -} - int claim_fiq(struct fiq_handler *f) { int ret = 0; @@ -174,8 +133,8 @@ void disable_fiq(int fiq) } EXPORT_SYMBOL(set_fiq_handler); -EXPORT_SYMBOL(set_fiq_regs); -EXPORT_SYMBOL(get_fiq_regs); +EXPORT_SYMBOL(__set_fiq_regs); /* defined in fiqasm.S */ +EXPORT_SYMBOL(__get_fiq_regs); /* defined in fiqasm.S */ EXPORT_SYMBOL(claim_fiq); EXPORT_SYMBOL(release_fiq); EXPORT_SYMBOL(enable_fiq); |