path: root/arch/powerpc/kernel/interrupt_64.S

#include <asm/asm-offsets.h>
#include <asm/bug.h>
#ifdef CONFIG_PPC_BOOK3S
#include <asm/exception-64s.h>
#else
#include <asm/exception-64e.h>
#endif
#include <asm/feature-fixups.h>
#include <asm/head-64.h>
#include <asm/hw_irq.h>
#include <asm/kup.h>
#include <asm/mmu.h>
#include <asm/ppc_asm.h>
#include <asm/ptrace.h>

	.align 7

.macro DEBUG_SRR_VALID srr
#ifdef CONFIG_PPC_RFI_SRR_DEBUG
	.ifc \srr,srr
	mfspr	r11,SPRN_SRR0
	ld	r12,_NIP(r1)
	clrrdi  r11,r11,2
	clrrdi  r12,r12,2
100:	tdne	r11,r12
	EMIT_WARN_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
	mfspr	r11,SPRN_SRR1
	ld	r12,_MSR(r1)
100:	tdne	r11,r12
	EMIT_WARN_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
	.else
	mfspr	r11,SPRN_HSRR0
	ld	r12,_NIP(r1)
	clrrdi  r11,r11,2
	clrrdi  r12,r12,2
100:	tdne	r11,r12
	EMIT_WARN_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
	mfspr	r11,SPRN_HSRR1
	ld	r12,_MSR(r1)
100:	tdne	r11,r12
	EMIT_WARN_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
	.endif
#endif
.endm

#ifdef CONFIG_PPC_BOOK3S
.macro system_call_vectored name trapnr
	.globl system_call_vectored_\name
system_call_vectored_\name:
_ASM_NOKPROBE_SYMBOL(system_call_vectored_\name)
	SCV_INTERRUPT_TO_KERNEL
	mr	r10,r1
	ld	r1,PACAKSAVE(r13)
	std	r10,0(r1)
	std	r11,_LINK(r1)
	std	r11,_NIP(r1)	/* Saved LR is also the next instruction */
	std	r12,_MSR(r1)
	std	r0,GPR0(r1)
	std	r10,GPR1(r1)
	std	r2,GPR2(r1)
	LOAD_PACA_TOC()
	mfcr	r12
	li	r11,0
	/* Save syscall parameters in r3-r8 */
	SAVE_GPRS(3, 8, r1)
	/* Zero r9-r12, this should only be required when restoring all GPRs */
	std	r11,GPR9(r1)
	std	r11,GPR10(r1)
	std	r11,GPR11(r1)
	std	r11,GPR12(r1)
	std	r9,GPR13(r1)
	SAVE_NVGPRS(r1)
	std	r11,_XER(r1)
	std	r11,_CTR(r1)

	li	r11,\trapnr
	std	r11,_TRAP(r1)
	std	r12,_CCR(r1)
	std	r3,ORIG_GPR3(r1)
	LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER)
	std	r11,STACK_INT_FRAME_MARKER(r1)		/* "regs" marker */
	/* Calling convention has r3 = regs, r4 = orig r0 */
	addi	r3,r1,STACK_INT_FRAME_REGS
	mr	r4,r0

BEGIN_FTR_SECTION
	HMT_MEDIUM
END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)

	/*
	 * scv enters with MSR[EE]=1 and is immediately considered soft-masked.
	 * The entry vector already sets PACAIRQSOFTMASK to IRQS_ALL_DISABLED,
	 * and interrupts may be masked and pending already.
	 * system_call_exception() will call trace_hardirqs_off() which means
	 * interrupts could already have been blocked before trace_hardirqs_off,
	 * but this is the best we can do.
	 */

	/*
	 * Zero user registers to prevent influencing speculative execution
	 * state of kernel code.
	 */
	SANITIZE_SYSCALL_GPRS()
	bl	CFUNC(system_call_exception)

.Lsyscall_vectored_\name\()_exit:
	addi	r4,r1,STACK_INT_FRAME_REGS
	li	r5,1 /* scv */
	bl	CFUNC(syscall_exit_prepare)
	std	r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
.Lsyscall_vectored_\name\()_rst_start:
	lbz	r11,PACAIRQHAPPENED(r13)
	andi.	r11,r11,(~PACA_IRQ_HARD_DIS)@l
	bne-	syscall_vectored_\name\()_restart
	li	r11,IRQS_ENABLED
	stb	r11,PACAIRQSOFTMASK(r13)
	li	r11,0
	stb	r11,PACAIRQHAPPENED(r13) # clear out possible HARD_DIS

	ld	r2,_CCR(r1)
	ld	r4,_NIP(r1)
	ld	r5,_MSR(r1)

BEGIN_FTR_SECTION
	stdcx.	r0,0,r1			/* to clear the reservation */
END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)

BEGIN_FTR_SECTION
	HMT_MEDIUM_LOW
END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)

	SANITIZE_RESTORE_NVGPRS()
	cmpdi	r3,0
	bne	.Lsyscall_vectored_\name\()_restore_regs

	/* rfscv returns with LR->NIA and CTR->MSR */
	mtlr	r4
	mtctr	r5

	/* Could zero these as per ABI, but we may consider a stricter ABI
	 * which preserves these if libc implementations can benefit, so
	 * restore them for now until further measurement is done. */
	REST_GPR(0, r1)
	REST_GPRS(4, 8, r1)
	/* Zero volatile regs that may contain sensitive kernel data */
	ZEROIZE_GPRS(9, 12)
	mtspr	SPRN_XER,r0

	/*
	 * We don't need to restore AMR on the way back to userspace for KUAP.
	 * The value of AMR only matters while we're in the kernel.
	 */
	mtcr	r2
	REST_GPRS(2, 3, r1)
	REST_GPR(13, r1)
	REST_GPR(1, r1)
	RFSCV_TO_USER
	b	.	/* prevent speculative execution */

.Lsyscall_vectored_\name\()_restore_regs:
	mtspr	SPRN_SRR0,r4
	mtspr	SPRN_SRR1,r5

	ld	r3,_CTR(r1)
	ld	r4,_LINK(r1)
	ld	r5,_XER(r1)

	HANDLER_RESTORE_NVGPRS()
	REST_GPR(0, r1)
	mtcr	r2
	mtctr	r3
	mtlr	r4
	mtspr	SPRN_XER,r5
	REST_GPRS(2, 13, r1)
	REST_GPR(1, r1)
	RFI_TO_USER
.Lsyscall_vectored_\name\()_rst_end:

syscall_vectored_\name\()_restart:
_ASM_NOKPROBE_SYMBOL(syscall_vectored_\name\()_restart)
	GET_PACA(r13)
	ld	r1,PACA_EXIT_SAVE_R1(r13)
	LOAD_PACA_TOC()
	ld	r3,RESULT(r1)
	addi	r4,r1,STACK_INT_FRAME_REGS
	li	r11,IRQS_ALL_DISABLED
	stb	r11,PACAIRQSOFTMASK(r13)
	bl	CFUNC(syscall_exit_restart)
	std	r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
	b	.Lsyscall_vectored_\name\()_rst_start
1:

SOFT_MASK_TABLE(.Lsyscall_vectored_\name\()_rst_start, 1b)
RESTART_TABLE(.Lsyscall_vectored_\name\()_rst_start, .Lsyscall_vectored_\name\()_rst_end, syscall_vectored_\name\()_restart)

.endm

system_call_vectored common 0x3000

/*
 * We instantiate another entry copy for the SIGILL variant, with TRAP=0x7ff0
 * which is tested by system_call_exception when r0 is -1 (as set by vector
 * entry code).
 */
system_call_vectored sigill 0x7ff0

#endif /* CONFIG_PPC_BOOK3S */

	.balign IFETCH_ALIGN_BYTES
	.globl system_call_common_real
system_call_common_real:
_ASM_NOKPROBE_SYMBOL(system_call_common_real)
	ld	r10,PACAKMSR(r13)	/* get MSR value for kernel */
	mtmsrd	r10

	.balign IFETCH_ALIGN_BYTES
	.globl system_call_common
system_call_common:
_ASM_NOKPROBE_SYMBOL(system_call_common)
	mr	r10,r1
	ld	r1,PACAKSAVE(r13)
	std	r10,0(r1)
	std	r11,_NIP(r1)
	std	r12,_MSR(r1)
	std	r0,GPR0(r1)
	std	r10,GPR1(r1)
	std	r2,GPR2(r1)
#ifdef CONFIG_PPC_E500
START_BTB_FLUSH_SECTION
	BTB_FLUSH(r10)
END_BTB_FLUSH_SECTION
#endif
	LOAD_PACA_TOC()
	mfcr	r12
	li	r11,0
	/* Save syscall parameters in r3-r8 */
	SAVE_GPRS(3, 8, r1)
	/* Zero r9-r12, this should only be required when restoring all GPRs */
	std	r11,GPR9(r1)
	std	r11,GPR10(r1)
	std	r11,GPR11(r1)
	std	r11,GPR12(r1)
	std	r9,GPR13(r1)
	SAVE_NVGPRS(r1)
	std	r11,_XER(r1)
	std	r11,_CTR(r1)
	mflr	r10

	/*
	 * This clears CR0.SO (bit 28), which is the error indication on
	 * return from this system call.
	 */
	rldimi	r12,r11,28,(63-28)
	li	r11,0xc00
	std	r10,_LINK(r1)
	std	r11,_TRAP(r1)
	std	r12,_CCR(r1)
	std	r3,ORIG_GPR3(r1)
	LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER)
	std	r11,STACK_INT_FRAME_MARKER(r1)		/* "regs" marker */
	/* Calling convention has r3 = regs, r4 = orig r0 */
	addi	r3,r1,STACK_INT_FRAME_REGS
	mr	r4,r0

#ifdef CONFIG_PPC_BOOK3S</