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

Commit 79b5c8db authored by Mihai Caraman's avatar Mihai Caraman Committed by Benjamin Herrenschmidt
Browse files

powerpc/booke64: Eemove mfspr srr1 duplicate in exception prolog 



Refactor exception prolog to get rid of mfspr srr1 duplicate. This was
introduced by KVM integration, with DO_KVM macro logic expecting srr1 value
earlier in r11.
Reserve r11 to hold srr1's value also required at the end of the prolog and
free up r10 to serve as spare in addition macros.
For syscalls case this change does not add any performance penalty. For irq
soft-disabled case the change adds a store/load of conditional register value
to/from a paca slot. Paca slots fit in one 64-byte cache line so these
additional operations have little impact on performance.

Signed-off-by: default avatarMihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent fecff0f7

arch/powerpc/kernel/exceptions-64e.S

+32 −35
Original line number Diff line number Diff line
@@ -45,10 +45,9 @@ 
	mfcr	r10;			/* save CR */			    \

	mfspr	r11,SPRN_##type##_SRR1;/* what are we coming from */	    \

	DO_KVM	intnum,SPRN_##type##_SRR1;    /* KVM hook */		    \

	stw	r10,PACA_EX##type+EX_CR(r13); /* save old CR in the PACA */ \

	addition;			/* additional code for that exc. */ \

	std	r1,PACA_EX##type+EX_R1(r13); /* save old r1 in the PACA */  \

	stw	r10,PACA_EX##type+EX_CR(r13); /* save old CR in the PACA */ \

	mfspr	r11,SPRN_##type##_SRR1;/* what are we coming from */	    \

	type##_SET_KSTACK;		/* get special stack if necessary */\

	andi.	r10,r11,MSR_PR;		/* save stack pointer */	    \

	beq	1f;			/* branch around if supervisor */   \
@@ -109,8 +108,8 @@ 
#define PROLOG_ADDITION_NONE_MC(n)



#define PROLOG_ADDITION_MASKABLE_GEN(n)					    \

	lbz	r11,PACASOFTIRQEN(r13); /* are irqs soft-disabled ? */	    \

	cmpwi	cr0,r11,0;		/* yes -> go out of line */	    \

	lbz	r10,PACASOFTIRQEN(r13); /* are irqs soft-disabled ? */	    \

	cmpwi	cr0,r10,0;		/* yes -> go out of line */	    \

	beq	masked_interrupt_book3e_##n



#define PROLOG_ADDITION_2REGS_GEN(n)					    \
@@ -624,44 +623,42 @@ kernel_dbg_exc: 
 * accordingly and if the interrupt is level sensitive, we hard disable

 */



.macro masked_interrupt_book3e paca_irq full_mask

	lbz	r10,PACAIRQHAPPENED(r13)

	ori	r10,r10,\paca_irq

	stb	r10,PACAIRQHAPPENED(r13)



	.if \full_mask == 1

	rldicl	r10,r11,48,1		/* clear MSR_EE */

	rotldi	r11,r10,16

	mtspr	SPRN_SRR1,r11

	.endif



	lwz	r11,PACA_EXGEN+EX_CR(r13)

	mtcr	r11

	ld	r10,PACA_EXGEN+EX_R10(r13)

	ld	r11,PACA_EXGEN+EX_R11(r13)

	mfspr	r13,SPRN_SPRG_GEN_SCRATCH

	rfi

	b	.

.endm



masked_interrupt_book3e_0x500:

	/* XXX When adding support for EPR, use PACA_IRQ_EE_EDGE */

	li	r11,PACA_IRQ_EE

	b	masked_interrupt_book3e_full_mask

	// XXX When adding support for EPR, use PACA_IRQ_EE_EDGE

	masked_interrupt_book3e PACA_IRQ_EE 1



masked_interrupt_book3e_0x900:

	ACK_DEC(r11);

	li	r11,PACA_IRQ_DEC

	b	masked_interrupt_book3e_no_mask

	ACK_DEC(r10);

	masked_interrupt_book3e PACA_IRQ_DEC 0



masked_interrupt_book3e_0x980:

	ACK_FIT(r11);

	li	r11,PACA_IRQ_DEC

	b	masked_interrupt_book3e_no_mask

	ACK_FIT(r10);

	masked_interrupt_book3e PACA_IRQ_DEC 0



masked_interrupt_book3e_0x280:

masked_interrupt_book3e_0x2c0:

	li	r11,PACA_IRQ_DBELL

	b	masked_interrupt_book3e_no_mask

	masked_interrupt_book3e PACA_IRQ_DBELL 0



masked_interrupt_book3e_no_mask:

	mtcr	r10

	lbz	r10,PACAIRQHAPPENED(r13)

	or	r10,r10,r11

	stb	r10,PACAIRQHAPPENED(r13)

	b	1f

masked_interrupt_book3e_full_mask:

	mtcr	r10

	lbz	r10,PACAIRQHAPPENED(r13)

	or	r10,r10,r11

	stb	r10,PACAIRQHAPPENED(r13)

	mfspr	r10,SPRN_SRR1

	rldicl	r11,r10,48,1		/* clear MSR_EE */

	rotldi	r10,r11,16

	mtspr	SPRN_SRR1,r10

1:	ld	r10,PACA_EXGEN+EX_R10(r13);

	ld	r11,PACA_EXGEN+EX_R11(r13);

	mfspr	r13,SPRN_SPRG_GEN_SCRATCH;

	rfi

	b	.

/*

 * Called from arch_local_irq_enable when an interrupt needs

 * to be resent. r3 contains either 0x500,0x900,0x260 or 0x280