MIPS: Netlogic: Optimize and fix write_c0_eimr()

Remove the irq save/restore from write_c0_eimr(), as it is always called
with interrupts off.

This allows us to remove workaround in write_c0_eimr() to fix up the
flags used by local_irq_save. This fixup worked on XLR, but will break
when 32-bit support is added to r2 cpus like XLP.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Patchwork: http://patchwork.linux-mips.org/patch/5022/
Acked-by: John Crispin <blogic@openwrt.org>
This commit is contained in:
Jayachandran C 2013-03-23 17:27:53 +00:00 committed by Ralf Baechle
parent 042df4fa28
commit 33ff712aef

View File

@ -43,16 +43,15 @@
#define write_c0_eirr(val) __write_64bit_c0_register($9, 6, val)
/*
* Writing EIMR in 32 bit is a special case, the lower 8 bit of the
* EIMR is shadowed in the status register, so we cannot save and
* restore status register for split read.
* NOTE: Do not save/restore flags around write_c0_eimr().
* On non-R2 platforms the flags has part of EIMR that is shadowed in STATUS
* register. Restoring flags will overwrite the lower 8 bits of EIMR.
*
* Call with interrupts disabled.
*/
#define write_c0_eimr(val) \
do { \
if (sizeof(unsigned long) == 4) { \
unsigned long __flags; \
\
local_irq_save(__flags); \
__asm__ __volatile__( \
".set\tmips64\n\t" \
"dsll\t%L0, %L0, 32\n\t" \
@ -62,8 +61,6 @@ do { \
"dmtc0\t%L0, $9, 7\n\t" \
".set\tmips0" \
: : "r" (val)); \
__flags = (__flags & 0xffff00ff) | (((val) & 0xff) << 8);\
local_irq_restore(__flags); \
} else \
__write_64bit_c0_register($9, 7, (val)); \
} while (0)