Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c976a584 authored by Stepan Moskovchenko's avatar Stepan Moskovchenko Committed by Stephen Boyd
Browse files

arm: Make the WFE macro unconditional 



Remove the condition argument from the WFE macro in the
spinlock code so it can support a WFE fixup needed on
certain Krait CPUs.

Change-Id: I8b4f85f0e7c130dff1e14fe275fda14a43e6f3f4
Signed-off-by: default avatarStepan Moskovchenko <stepanm@codeaurora.org>
parent ac2f43fa

arch/arm/include/asm/spinlock.h

+12 −16
Original line number Diff line number Diff line
@@ -21,25 +21,17 @@ 
#ifdef CONFIG_THUMB2_KERNEL

#define SEV		ALT_SMP("sev.w", "nop.w")

/*

 * For Thumb-2, special care is needed to ensure that the conditional WFE

 * instruction really does assemble to exactly 4 bytes (as required by

 * the SMP_ON_UP fixup code).   By itself "wfene" might cause the

 * assembler to insert a extra (16-bit) IT instruction, depending on the

 * presence or absence of neighbouring conditional instructions.

 *

 * To avoid this unpredictableness, an approprite IT is inserted explicitly:

 * the assembler won't change IT instructions which are explicitly present

 * in the input.

 * Both instructions given to the ALT_SMP macro need to be the same size, to

 * allow the SMP_ON_UP fixups to function correctly. Hence the explicit encoding

 * specifications.

 */

#define WFE(cond)	ALT_SMP(		\

	"it " cond "\n\t"			\

	"wfe" cond ".n",			\

						\

#define WFE()		ALT_SMP(		\

	"wfe.w",				\

	"nop.w"					\

)

#else

#define SEV		ALT_SMP("sev", "nop")

#define WFE(cond)	ALT_SMP("wfe" cond, "nop")

#define WFE()		ALT_SMP("wfe", "nop")

#endif



static inline void dsb_sev(void)
@@ -152,7 +144,9 @@ static inline void arch_write_lock(arch_rwlock_t *rw) 
	__asm__ __volatile__(

"1:	ldrex	%0, [%1]\n"

"	teq	%0, #0\n"

	WFE("ne")

"	beq	2f\n"

	WFE()

"2:\n"

"	strexeq	%0, %2, [%1]\n"

"	teq	%0, #0\n"

"	bne	1b"
@@ -219,7 +213,9 @@ static inline void arch_read_lock(arch_rwlock_t *rw) 
"1:	ldrex	%0, [%2]\n"

"	adds	%0, %0, #1\n"

"	strexpl	%1, %0, [%2]\n"

	WFE("mi")

"	bpl	2f\n"

	WFE()

"2:\n"

"	rsbpls	%0, %1, #0\n"

"	bmi	1b"

	: "=&r" (tmp), "=&r" (tmp2)