Commit a2dcbb32 authored by Michael Neuling's avatar Michael Neuling Committed by Benjamin Herrenschmidt
Browse files

powerpc: Add FP/VSX and VMX register load functions for transactional memory 



This adds functions to restore the state of the FP/VSX registers from
what's stored in the thread_struct.  Two version for FP/VSX are required
since one restores them from transactional/checkpoint side of the
thread_struct and the other from the speculated side.

Similar functions are added for VMX registers.

Signed-off-by: default avatarMatt Evans <matt@ozlabs.org>
Signed-off-by: default avatarMichael Neuling <mikey@neuling.org>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 98ae22e1

arch/powerpc/kernel/fpu.S

+54 −0
Original line number Diff line number Diff line
@@ -62,6 +62,60 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX); \ 
	__REST_32FPVSRS_TRANSACT(n,__REG_##c,__REG_##base)

#define SAVE_32FPVSRS(n,c,base) __SAVE_32FPVSRS(n,__REG_##c,__REG_##base)



#ifdef CONFIG_PPC_TRANSACTIONAL_MEM

/*

 * Wrapper to call load_up_fpu from C.

 * void do_load_up_fpu(struct pt_regs *regs);

 */

_GLOBAL(do_load_up_fpu)

	mflr	r0

	std	r0, 16(r1)

	stdu	r1, -112(r1)



	subi	r6, r3, STACK_FRAME_OVERHEAD

	/* load_up_fpu expects r12=MSR, r13=PACA, and returns

	 * with r12 = new MSR.

	 */

	ld	r12,_MSR(r6)

	GET_PACA(r13)



	bl	load_up_fpu

	std	r12,_MSR(r6)



	ld	r0, 112+16(r1)

	addi	r1, r1, 112

	mtlr	r0

	blr





/* void do_load_up_transact_fpu(struct thread_struct *thread)

 *

 * This is similar to load_up_fpu but for the transactional version of the FP

 * register set.  It doesn't mess with the task MSR or valid flags.

 * Furthermore, we don't do lazy FP with TM currently.

 */

_GLOBAL(do_load_up_transact_fpu)

	mfmsr	r6

	ori	r5,r6,MSR_FP

#ifdef CONFIG_VSX

BEGIN_FTR_SECTION

	oris	r5,r5,MSR_VSX@h

END_FTR_SECTION_IFSET(CPU_FTR_VSX)

#endif

	SYNC

	MTMSRD(r5)



	lfd	fr0,THREAD_TRANSACT_FPSCR(r3)

	MTFSF_L(fr0)

	REST_32FPVSRS_TRANSACT(0, R4, R3)



	/* FP/VSX off again */

	MTMSRD(r6)

	SYNC



	blr

#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */



/*

 * This task wants to use the FPU now.

 * On UP, disable FP for the task which had the FPU previously,

arch/powerpc/kernel/vector.S

+51 −0
Original line number Diff line number Diff line
@@ -7,6 +7,57 @@ 
#include <asm/page.h>

#include <asm/ptrace.h>



#ifdef CONFIG_PPC_TRANSACTIONAL_MEM

/*

 * Wrapper to call load_up_altivec from C.

 * void do_load_up_altivec(struct pt_regs *regs);

 */

_GLOBAL(do_load_up_altivec)

	mflr	r0

	std	r0, 16(r1)

	stdu	r1, -112(r1)



	subi	r6, r3, STACK_FRAME_OVERHEAD

	/* load_up_altivec expects r12=MSR, r13=PACA, and returns

	 * with r12 = new MSR.

	 */

	ld	r12,_MSR(r6)

	GET_PACA(r13)

	bl	load_up_altivec

	std	r12,_MSR(r6)



	ld	r0, 112+16(r1)

	addi	r1, r1, 112

	mtlr	r0

	blr



/* void do_load_up_transact_altivec(struct thread_struct *thread)

 *

 * This is similar to load_up_altivec but for the transactional version of the

 * vector regs.  It doesn't mess with the task MSR or valid flags.

 * Furthermore, VEC laziness is not supported with TM currently.

 */

_GLOBAL(do_load_up_transact_altivec)

	mfmsr	r6

	oris	r5,r6,MSR_VEC@h

	MTMSRD(r5)

	isync



	li	r4,1

	stw	r4,THREAD_USED_VR(r3)



	li	r10,THREAD_TRANSACT_VSCR

	lvx	vr0,r10,r3

	mtvscr	vr0

	REST_32VRS_TRANSACT(0,r4,r3)



	/* Disable VEC again. */

	MTMSRD(r6)

	isync



	blr

#endif



/*

 * load_up_altivec(unused, unused, tsk)

 * Disable VMX for the task which had it previously,

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