Commit 1b4d4a79 authored by Nicholas Piggin's avatar Nicholas Piggin Committed by Michael Ellerman
Browse files

powerpc/64s/exception: use a gas macro for system call handler code 



No generated code change.

Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent f945478d

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

+55 −72
Original line number Diff line number Diff line
@@ -1607,6 +1607,7 @@ EXC_COMMON(trap_0b_common, 0xb00, unknown_exception) 
 * without saving, though xer is not a good idea to use, as hardware may

 * interpret some bits so it may be costly to change them.

 */

.macro SYSTEM_CALL virt

#ifdef CONFIG_KVM_BOOK3S_64_HANDLER

	/*

	 * There is a little bit of juggling to get syscall and hcall
@@ -1616,95 +1617,77 @@ EXC_COMMON(trap_0b_common, 0xb00, unknown_exception) 
	 * Userspace syscalls have already saved the PPR, hcalls must save

	 * it before setting HMT_MEDIUM.

	 */

#define SYSCALL_KVMTEST							\

	mtctr	r13;							\

	GET_PACA(r13);							\

	std	r10,PACA_EXGEN+EX_R10(r13);				\

	INTERRUPT_TO_KERNEL;						\

	KVMTEST EXC_STD 0xc00 ; /* uses r10, branch to do_kvm_0xc00_system_call */ \

	HMT_MEDIUM;							\

	mfctr	r9;



	mtctr	r13

	GET_PACA(r13)

	std	r10,PACA_EXGEN+EX_R10(r13)

	INTERRUPT_TO_KERNEL

	KVMTEST EXC_STD 0xc00 /* uses r10, branch to do_kvm_0xc00_system_call */

	HMT_MEDIUM

	mfctr	r9

#else

#define SYSCALL_KVMTEST							\

	HMT_MEDIUM;							\

	mr	r9,r13;							\

	GET_PACA(r13);							\

	INTERRUPT_TO_KERNEL;

	HMT_MEDIUM

	mr	r9,r13

	GET_PACA(r13)

	INTERRUPT_TO_KERNEL

#endif



#define LOAD_SYSCALL_HANDLER(reg)					\

	__LOAD_HANDLER(reg, system_call_common)



/*

 * After SYSCALL_KVMTEST, we reach here with PACA in r13, r13 in r9,

 * and HMT_MEDIUM.

 */

#define SYSCALL_REAL	 					\

	mfspr	r11,SPRN_SRR0 ;					\

	mfspr	r12,SPRN_SRR1 ;					\

	LOAD_SYSCALL_HANDLER(r10) ; 				\

	mtspr	SPRN_SRR0,r10 ; 				\

	ld	r10,PACAKMSR(r13) ;				\

	mtspr	SPRN_SRR1,r10 ; 				\

	RFI_TO_KERNEL ;						\

	b	. ;	/* prevent speculative execution */



#ifdef CONFIG_PPC_FAST_ENDIAN_SWITCH

#define SYSCALL_FASTENDIAN_TEST					\

BEGIN_FTR_SECTION						\

	cmpdi	r0,0x1ebe ; 					\

	beq-	1f ;						\

END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)				\



#define SYSCALL_FASTENDIAN					\

	/* Fast LE/BE switch system call */			\

1:	mfspr	r12,SPRN_SRR1 ;					\

	xori	r12,r12,MSR_LE ;				\

	mtspr	SPRN_SRR1,r12 ;					\

	mr	r13,r9 ;					\

	RFI_TO_USER ;	/* return to userspace */		\

	b	. ;	/* prevent speculative execution */

#else

#define SYSCALL_FASTENDIAN_TEST

#define SYSCALL_FASTENDIAN

#endif /* CONFIG_PPC_FAST_ENDIAN_SWITCH */

BEGIN_FTR_SECTION

	cmpdi	r0,0x1ebe

	beq-	1f

END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)

#endif

	/* We reach here with PACA in r13, r13 in r9, and HMT_MEDIUM. */



#if defined(CONFIG_RELOCATABLE)

	.if ! \virt

	mfspr	r11,SPRN_SRR0

	mfspr	r12,SPRN_SRR1

	__LOAD_HANDLER(r10, system_call_common)

	mtspr	SPRN_SRR0,r10

	ld	r10,PACAKMSR(r13)

	mtspr	SPRN_SRR1,r10

	RFI_TO_KERNEL

	b	.	/* prevent speculative execution */

	.else

#ifdef CONFIG_RELOCATABLE

	/*

	 * We can't branch directly so we do it via the CTR which

	 * is volatile across system calls.

	 */

#define SYSCALL_VIRT						\

	LOAD_SYSCALL_HANDLER(r10) ;				\

	mtctr	r10 ;						\

	mfspr	r11,SPRN_SRR0 ;					\

	mfspr	r12,SPRN_SRR1 ;					\

	li	r10,MSR_RI ;					\

	mtmsrd 	r10,1 ;						\

	bctr ;

	__LOAD_HANDLER(r10, system_call_common)

	mtctr	r10

	mfspr	r11,SPRN_SRR0

	mfspr	r12,SPRN_SRR1

	li	r10,MSR_RI

	mtmsrd 	r10,1

	bctr

#else

	/* We can branch directly */

#define SYSCALL_VIRT						\

	mfspr	r11,SPRN_SRR0 ;					\

	mfspr	r12,SPRN_SRR1 ;					\

	li	r10,MSR_RI ;					\

	mtmsrd 	r10,1 ;			/* Set RI (EE=0) */	\

	b	system_call_common ;

	mfspr	r11,SPRN_SRR0

	mfspr	r12,SPRN_SRR1

	li	r10,MSR_RI

	mtmsrd 	r10,1			/* Set RI (EE=0) */

	b	system_call_common

#endif

	.endif



#ifdef CONFIG_PPC_FAST_ENDIAN_SWITCH

	/* Fast LE/BE switch system call */

1:	mfspr	r12,SPRN_SRR1

	xori	r12,r12,MSR_LE

	mtspr	SPRN_SRR1,r12

	mr	r13,r9

	RFI_TO_USER	/* return to userspace */

	b	.	/* prevent speculative execution */

#endif

.endm



EXC_REAL_BEGIN(system_call, 0xc00, 0x100)

	SYSCALL_KVMTEST /* loads PACA into r13, and saves r13 to r9 */

	SYSCALL_FASTENDIAN_TEST

	SYSCALL_REAL

	SYSCALL_FASTENDIAN

	SYSTEM_CALL 0

EXC_REAL_END(system_call, 0xc00, 0x100)



EXC_VIRT_BEGIN(system_call, 0x4c00, 0x100)

	SYSCALL_KVMTEST /* loads PACA into r13, and saves r13 to r9 */

	SYSCALL_FASTENDIAN_TEST

	SYSCALL_VIRT

	SYSCALL_FASTENDIAN

	SYSTEM_CALL 1

EXC_VIRT_END(system_call, 0x4c00, 0x100)



#ifdef CONFIG_KVM_BOOK3S_64_HANDLER