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-rw-r--r--arch/powerpc/kernel/interrupt_64.S770
1 files changed, 770 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S
new file mode 100644
index 000000000000..4063e8a3f704
--- /dev/null
+++ b/arch/powerpc/kernel/interrupt_64.S
@@ -0,0 +1,770 @@
+#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>
+#include <asm/tm.h>
+
+ .section ".toc","aw"
+SYS_CALL_TABLE:
+ .tc sys_call_table[TC],sys_call_table
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYS_CALL_TABLE:
+ .tc compat_sys_call_table[TC],compat_sys_call_table
+#endif
+ .previous
+
+ .align 7
+
+.macro DEBUG_SRR_VALID srr
+#ifdef CONFIG_PPC_RFI_SRR_DEBUG
+ .ifc \srr,srr
+ mfspr r11,SPRN_SRR0
+ ld r12,_NIP(r1)
+100: tdne r11,r12
+ EMIT_BUG_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
+ mfspr r11,SPRN_SRR1
+ ld r12,_MSR(r1)
+100: tdne r11,r12
+ EMIT_BUG_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
+ .else
+ mfspr r11,SPRN_HSRR0
+ ld r12,_NIP(r1)
+100: tdne r11,r12
+ EMIT_BUG_ENTRY 100b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
+ mfspr r11,SPRN_HSRR1
+ ld r12,_MSR(r1)
+100: tdne r11,r12
+ EMIT_BUG_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)
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+BEGIN_FTR_SECTION
+ extrdi. r10, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */
+ bne tabort_syscall
+END_FTR_SECTION_IFSET(CPU_FTR_TM)
+#endif
+ SCV_INTERRUPT_TO_KERNEL
+ 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)
+ ld r2,PACATOC(r13)
+ mfcr r12
+ li r11,0
+ /* Can we avoid saving r3-r8 in common case? */
+ std r3,GPR3(r1)
+ std r4,GPR4(r1)
+ std r5,GPR5(r1)
+ std r6,GPR6(r1)
+ std r7,GPR7(r1)
+ std r8,GPR8(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,_LINK(r1)
+ std r11,_CTR(r1)
+
+ li r11,\trapnr
+ std r11,_TRAP(r1)
+ std r12,_CCR(r1)
+ addi r10,r1,STACK_FRAME_OVERHEAD
+ ld r11,exception_marker@toc(r2)
+ std r11,-16(r10) /* "regshere" marker */
+
+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.
+ */
+
+ /* Calling convention has r9 = orig r0, r10 = regs */
+ mr r9,r0
+ bl system_call_exception
+
+.Lsyscall_vectored_\name\()_exit:
+ addi r4,r1,STACK_FRAME_OVERHEAD
+ li r5,1 /* scv */
+ bl 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)
+
+ 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. */
+ ld r0,GPR0(r1)
+ ld r4,GPR4(r1)
+ ld r5,GPR5(r1)
+ ld r6,GPR6(r1)
+ ld r7,GPR7(r1)
+ ld r8,GPR8(r1)
+ /* Zero volatile regs that may contain sensitive kernel data */
+ li r9,0
+ li r10,0
+ li r11,0
+ li r12,0
+ 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
+ ld r2,GPR2(r1)
+ ld r3,GPR3(r1)
+ ld r13,GPR13(r1)
+ ld r1,GPR1(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)
+
+ REST_NVGPRS(r1)
+ ld r0,GPR0(r1)
+ mtcr r2
+ mtctr r3
+ mtlr r4
+ mtspr SPRN_XER,r5
+ REST_10GPRS(2, r1)
+ REST_2GPRS(12, r1)
+ ld r1,GPR1(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)
+ ld r2,PACATOC(r13)
+ ld r3,RESULT(r1)
+ addi r4,r1,STACK_FRAME_OVERHEAD
+ li r11,IRQS_ALL_DISABLED
+ stb r11,PACAIRQSOFTMASK(r13)
+ bl 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
+
+
+/*
+ * Entered via kernel return set up by kernel/sstep.c, must match entry regs
+ */
+ .globl system_call_vectored_emulate
+system_call_vectored_emulate:
+_ASM_NOKPROBE_SYMBOL(system_call_vectored_emulate)
+ li r10,IRQS_ALL_DISABLED
+ stb r10,PACAIRQSOFTMASK(r13)
+ b system_call_vectored_common
+#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)
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+BEGIN_FTR_SECTION
+ extrdi. r10, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */
+ bne tabort_syscall
+END_FTR_SECTION_IFSET(CPU_FTR_TM)
+#endif
+ 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_FSL_BOOK3E
+START_BTB_FLUSH_SECTION
+ BTB_FLUSH(r10)
+END_BTB_FLUSH_SECTION
+#endif
+ ld r2,PACATOC(r13)
+ mfcr r12
+ li r11,0
+ /* Can we avoid saving r3-r8 in common case? */
+ std r3,GPR3(r1)
+ std r4,GPR4(r1)
+ std r5,GPR5(r1)
+ std r6,GPR6(r1)
+ std r7,GPR7(r1)
+ std r8,GPR8(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)
+ addi r10,r1,STACK_FRAME_OVERHEAD
+ ld r11,exception_marker@toc(r2)
+ std r11,-16(r10) /* "regshere" marker */
+
+#ifdef CONFIG_PPC_BOOK3S
+ li r11,1
+ stb r11,PACASRR_VALID(r13)
+#endif
+
+ /*
+ * We always enter kernel from userspace with irq soft-mask enabled and
+ * nothing pending. system_call_exception() will call
+ * trace_hardirqs_off().
+ */
+ li r11,IRQS_ALL_DISABLED
+ li r12,-1 /* Set MSR_EE and MSR_RI */
+ stb r11,PACAIRQSOFTMASK(r13)
+ mtmsrd r12,1
+
+ /* Calling convention has r9 = orig r0, r10 = regs */
+ mr r9,r0
+ bl system_call_exception
+
+.Lsyscall_exit:
+ addi r4,r1,STACK_FRAME_OVERHEAD
+ li r5,0 /* !scv */
+ bl syscall_exit_prepare
+ std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
+#ifdef CONFIG_PPC_BOOK3S
+.Lsyscall_rst_start:
+ lbz r11,PACAIRQHAPPENED(r13)
+ andi. r11,r11,(~PACA_IRQ_HARD_DIS)@l
+ bne- syscall_restart
+#endif
+ 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 r6,_LINK(r1)
+ mtlr r6
+
+#ifdef CONFIG_PPC_BOOK3S
+ lbz r4,PACASRR_VALID(r13)
+ cmpdi r4,0
+ bne 1f
+ li r4,0
+ stb r4,PACASRR_VALID(r13)
+#endif
+ ld r4,_NIP(r1)
+ ld r5,_MSR(r1)
+ mtspr SPRN_SRR0,r4
+ mtspr SPRN_SRR1,r5
+1:
+ DEBUG_SRR_VALID srr
+
+BEGIN_FTR_SECTION
+ stdcx. r0,0,r1 /* to clear the reservation */
+END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
+
+ cmpdi r3,0
+ bne .Lsyscall_restore_regs
+ /* Zero volatile regs that may contain sensitive kernel data */
+ li r0,0
+ li r4,0
+ li r5,0
+ li r6,0
+ li r7,0
+ li r8,0
+ li r9,0
+ li r10,0
+ li r11,0
+ li r12,0
+ mtctr r0
+ mtspr SPRN_XER,r0
+.Lsyscall_restore_regs_cont:
+
+BEGIN_FTR_SECTION
+ HMT_MEDIUM_LOW
+END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
+
+ /*
+ * 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
+ ld r2,GPR2(r1)
+ ld r3,GPR3(r1)
+ ld r13,GPR13(r1)
+ ld r1,GPR1(r1)
+ RFI_TO_USER
+ b . /* prevent speculative execution */
+
+.Lsyscall_restore_regs:
+ ld r3,_CTR(r1)
+ ld r4,_XER(r1)
+ REST_NVGPRS(r1)
+ mtctr r3
+ mtspr SPRN_XER,r4
+ ld r0,GPR0(r1)
+ REST_8GPRS(4, r1)
+ ld r12,GPR12(r1)
+ b .Lsyscall_restore_regs_cont
+.Lsyscall_rst_end:
+
+#ifdef CONFIG_PPC_BOOK3S
+syscall_restart:
+_ASM_NOKPROBE_SYMBOL(syscall_restart)
+ GET_PACA(r13)
+ ld r1,PACA_EXIT_SAVE_R1(r13)
+ ld r2,PACATOC(r13)
+ ld r3,RESULT(r1)
+ addi r4,r1,STACK_FRAME_OVERHEAD
+ li r11,IRQS_ALL_DISABLED
+ stb r11,PACAIRQSOFTMASK(r13)
+ bl syscall_exit_restart
+ std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
+ b .Lsyscall_rst_start
+1:
+
+SOFT_MASK_TABLE(.Lsyscall_rst_start, 1b)
+RESTART_TABLE(.Lsyscall_rst_start, .Lsyscall_rst_end, syscall_restart)
+#endif
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+tabort_syscall:
+_ASM_NOKPROBE_SYMBOL(tabort_syscall)
+ /* Firstly we need to enable TM in the kernel */
+ mfmsr r10
+ li r9, 1
+ rldimi r10, r9, MSR_TM_LG, 63-MSR_TM_LG
+ mtmsrd r10, 0
+
+ /* tabort, this dooms the transaction, nothing else */
+ li r9, (TM_CAUSE_SYSCALL|TM_CAUSE_PERSISTENT)
+ TABORT(R9)
+
+ /*
+ * Return directly to userspace. We have corrupted user register state,
+ * but userspace will never see that register state. Execution will
+ * resume after the tbegin of the aborted transaction with the
+ * checkpointed register state.
+ */
+ li r9, MSR_RI
+ andc r10, r10, r9
+ mtmsrd r10, 1
+ mtspr SPRN_SRR0, r11
+ mtspr SPRN_SRR1, r12
+ RFI_TO_USER
+ b . /* prevent speculative execution */
+#endif
+
+ /*
+ * If MSR EE/RI was never enabled, IRQs not reconciled, NVGPRs not
+ * touched, no exit work created, then this can be used.
+ */
+ .balign IFETCH_ALIGN_BYTES
+ .globl fast_interrupt_return_srr
+fast_interrupt_return_srr:
+_ASM_NOKPROBE_SYMBOL(fast_interrupt_return_srr)
+ kuap_check_amr r3, r4
+ ld r5,_MSR(r1)
+ andi. r0,r5,MSR_PR
+#ifdef CONFIG_PPC_BOOK3S
+ beq 1f
+ kuap_user_restore r3, r4
+ b .Lfast_user_interrupt_return_srr
+1: kuap_kernel_restore r3, r4
+ andi. r0,r5,MSR_RI
+ li r3,0 /* 0 return value, no EMULATE_STACK_STORE */
+ bne+ .Lfast_kernel_interrupt_return_srr
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl unrecoverable_exception
+ b . /* should not get here */
+#else
+ bne .Lfast_user_interrupt_return_srr
+ b .Lfast_kernel_interrupt_return_srr
+#endif
+
+.macro interrupt_return_macro srr
+ .balign IFETCH_ALIGN_BYTES
+ .globl interrupt_return_\srr
+interrupt_return_\srr\():
+_ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\())
+ ld r4,_MSR(r1)
+ andi. r0,r4,MSR_PR
+ beq interrupt_return_\srr\()_kernel
+interrupt_return_\srr\()_user: /* make backtraces match the _kernel variant */
+_ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_user)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl interrupt_exit_user_prepare
+ cmpdi r3,0
+ bne- .Lrestore_nvgprs_\srr
+.Lrestore_nvgprs_\srr\()_cont:
+ std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
+#ifdef CONFIG_PPC_BOOK3S
+.Linterrupt_return_\srr\()_user_rst_start:
+ lbz r11,PACAIRQHAPPENED(r13)
+ andi. r11,r11,(~PACA_IRQ_HARD_DIS)@l
+ bne- interrupt_return_\srr\()_user_restart
+#endif
+ li r11,IRQS_ENABLED
+ stb r11,PACAIRQSOFTMASK(r13)
+ li r11,0
+ stb r11,PACAIRQHAPPENED(r13) # clear out possible HARD_DIS
+
+.Lfast_user_interrupt_return_\srr\():
+#ifdef CONFIG_PPC_BOOK3S
+ .ifc \srr,srr
+ lbz r4,PACASRR_VALID(r13)
+ .else
+ lbz r4,PACAHSRR_VALID(r13)
+ .endif
+ cmpdi r4,0
+ li r4,0
+ bne 1f
+#endif
+ ld r11,_NIP(r1)
+ ld r12,_MSR(r1)
+ .ifc \srr,srr
+ mtspr SPRN_SRR0,r11
+ mtspr SPRN_SRR1,r12
+1:
+#ifdef CONFIG_PPC_BOOK3S
+ stb r4,PACASRR_VALID(r13)
+#endif
+ .else
+ mtspr SPRN_HSRR0,r11
+ mtspr SPRN_HSRR1,r12
+1:
+#ifdef CONFIG_PPC_BOOK3S
+ stb r4,PACAHSRR_VALID(r13)
+#endif
+ .endif
+ DEBUG_SRR_VALID \srr
+
+#ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
+ lbz r4,PACAIRQSOFTMASK(r13)
+ tdnei r4,IRQS_ENABLED
+#endif
+
+BEGIN_FTR_SECTION
+ ld r10,_PPR(r1)
+ mtspr SPRN_PPR,r10
+END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
+
+BEGIN_FTR_SECTION
+ stdcx. r0,0,r1 /* to clear the reservation */
+FTR_SECTION_ELSE
+ ldarx r0,0,r1
+ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
+
+ ld r3,_CCR(r1)
+ ld r4,_LINK(r1)
+ ld r5,_CTR(r1)
+ ld r6,_XER(r1)
+ li r0,0
+
+ REST_4GPRS(7, r1)
+ REST_2GPRS(11, r1)
+ REST_GPR(13, r1)
+
+ mtcr r3
+ mtlr r4
+ mtctr r5
+ mtspr SPRN_XER,r6
+
+ REST_4GPRS(2, r1)
+ REST_GPR(6, r1)
+ REST_GPR(0, r1)
+ REST_GPR(1, r1)
+ .ifc \srr,srr
+ RFI_TO_USER
+ .else
+ HRFI_TO_USER
+ .endif
+ b . /* prevent speculative execution */
+.Linterrupt_return_\srr\()_user_rst_end:
+
+.Lrestore_nvgprs_\srr\():
+ REST_NVGPRS(r1)
+ b .Lrestore_nvgprs_\srr\()_cont
+
+#ifdef CONFIG_PPC_BOOK3S
+interrupt_return_\srr\()_user_restart:
+_ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_user_restart)
+ GET_PACA(r13)
+ ld r1,PACA_EXIT_SAVE_R1(r13)
+ ld r2,PACATOC(r13)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ li r11,IRQS_ALL_DISABLED
+ stb r11,PACAIRQSOFTMASK(r13)
+ bl interrupt_exit_user_restart
+ std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
+ b .Linterrupt_return_\srr\()_user_rst_start
+1:
+
+SOFT_MASK_TABLE(.Linterrupt_return_\srr\()_user_rst_start, 1b)
+RESTART_TABLE(.Linterrupt_return_\srr\()_user_rst_start, .Linterrupt_return_\srr\()_user_rst_end, interrupt_return_\srr\()_user_restart)
+#endif
+
+ .balign IFETCH_ALIGN_BYTES
+interrupt_return_\srr\()_kernel:
+_ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl interrupt_exit_kernel_prepare
+
+ std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
+.Linterrupt_return_\srr\()_kernel_rst_start:
+ ld r11,SOFTE(r1)
+ cmpwi r11,IRQS_ENABLED
+ stb r11,PACAIRQSOFTMASK(r13)
+ bne 1f
+#ifdef CONFIG_PPC_BOOK3S
+ lbz r11,PACAIRQHAPPENED(r13)
+ andi. r11,r11,(~PACA_IRQ_HARD_DIS)@l
+ bne- interrupt_return_\srr\()_kernel_restart
+#endif
+ li r11,0
+ stb r11,PACAIRQHAPPENED(r13) # clear out possible HARD_DIS
+1:
+
+.Lfast_kernel_interrupt_return_\srr\():
+ cmpdi cr1,r3,0
+#ifdef CONFIG_PPC_BOOK3S
+ .ifc \srr,srr
+ lbz r4,PACASRR_VALID(r13)
+ .else
+ lbz r4,PACAHSRR_VALID(r13)
+ .endif
+ cmpdi r4,0
+ li r4,0
+ bne 1f
+#endif
+ ld r11,_NIP(r1)
+ ld r12,_MSR(r1)
+ .ifc \srr,srr
+ mtspr SPRN_SRR0,r11
+ mtspr SPRN_SRR1,r12
+1:
+#ifdef CONFIG_PPC_BOOK3S
+ stb r4,PACASRR_VALID(r13)
+#endif
+ .else
+ mtspr SPRN_HSRR0,r11
+ mtspr SPRN_HSRR1,r12
+1:
+#ifdef CONFIG_PPC_BOOK3S
+ stb r4,PACAHSRR_VALID(r13)
+#endif
+ .endif
+ DEBUG_SRR_VALID \srr
+
+BEGIN_FTR_SECTION
+ stdcx. r0,0,r1 /* to clear the reservation */
+FTR_SECTION_ELSE
+ ldarx r0,0,r1
+ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
+
+ ld r3,_LINK(r1)
+ ld r4,_CTR(r1)
+ ld r5,_XER(r1)
+ ld r6,_CCR(r1)
+ li r0,0
+
+ REST_4GPRS(7, r1)
+ REST_2GPRS(11, r1)
+
+ mtlr r3
+ mtctr r4
+ mtspr SPRN_XER,r5
+
+ /*
+ * Leaving a stale exception_marker on the stack can confuse
+ * the reliable stack unwinder later on. Clear it.
+ */
+ std r0,STACK_FRAME_OVERHEAD-16(r1)
+
+ REST_4GPRS(2, r1)
+
+ bne- cr1,1f /* emulate stack store */
+ mtcr r6
+ REST_GPR(6, r1)
+ REST_GPR(0, r1)
+ REST_GPR(1, r1)
+ .ifc \srr,srr
+ RFI_TO_KERNEL
+ .else
+ HRFI_TO_KERNEL
+ .endif
+ b . /* prevent speculative execution */
+
+1: /*
+ * Emulate stack store with update. New r1 value was already calculated
+ * and updated in our interrupt regs by emulate_loadstore, but we can't
+ * store the previous value of r1 to the stack before re-loading our
+ * registers from it, otherwise they could be clobbered. Use
+ * PACA_EXGEN as temporary storage to hold the store data, as
+ * interrupts are disabled here so it won't be clobbered.
+ */
+ mtcr r6
+ std r9,PACA_EXGEN+0(r13)
+ addi r9,r1,INT_FRAME_SIZE /* get original r1 */
+ REST_GPR(6, r1)
+ REST_GPR(0, r1)
+ REST_GPR(1, r1)
+ std r9,0(r1) /* perform store component of stdu */
+ ld r9,PACA_EXGEN+0(r13)
+
+ .ifc \srr,srr
+ RFI_TO_KERNEL
+ .else
+ HRFI_TO_KERNEL
+ .endif
+ b . /* prevent speculative execution */
+.Linterrupt_return_\srr\()_kernel_rst_end:
+
+#ifdef CONFIG_PPC_BOOK3S
+interrupt_return_\srr\()_kernel_restart:
+_ASM_NOKPROBE_SYMBOL(interrupt_return_\srr\()_kernel_restart)
+ GET_PACA(r13)
+ ld r1,PACA_EXIT_SAVE_R1(r13)
+ ld r2,PACATOC(r13)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ li r11,IRQS_ALL_DISABLED
+ stb r11,PACAIRQSOFTMASK(r13)
+ bl interrupt_exit_kernel_restart
+ std r1,PACA_EXIT_SAVE_R1(r13) /* save r1 for restart */
+ b .Linterrupt_return_\srr\()_kernel_rst_start
+1:
+
+SOFT_MASK_TABLE(.Linterrupt_return_\srr\()_kernel_rst_start, 1b)
+RESTART_TABLE(.Linterrupt_return_\srr\()_kernel_rst_start, .Linterrupt_return_\srr\()_kernel_rst_end, interrupt_return_\srr\()_kernel_restart)
+#endif
+
+.endm
+
+interrupt_return_macro srr
+#ifdef CONFIG_PPC_BOOK3S
+interrupt_return_macro hsrr
+
+ .globl __end_soft_masked
+__end_soft_masked:
+DEFINE_FIXED_SYMBOL(__end_soft_masked)
+#endif /* CONFIG_PPC_BOOK3S */
+
+#ifdef CONFIG_PPC_BOOK3S
+_GLOBAL(ret_from_fork_scv)
+ bl schedule_tail
+ REST_NVGPRS(r1)
+ li r3,0 /* fork() return value */
+ b .Lsyscall_vectored_common_exit
+#endif
+
+_GLOBAL(ret_from_fork)
+ bl schedule_tail
+ REST_NVGPRS(r1)
+ li r3,0 /* fork() return value */
+ b .Lsyscall_exit
+
+_GLOBAL(ret_from_kernel_thread)
+ bl schedule_tail
+ REST_NVGPRS(r1)
+ mtctr r14
+ mr r3,r15
+#ifdef PPC64_ELF_ABI_v2
+ mr r12,r14
+#endif
+ bctrl
+ li r3,0
+ b .Lsyscall_exit