From: Nicholas Piggin Date: Fri, 2 Aug 2019 10:56:36 +0000 (+1000) Subject: powerpc/64s/exception: machine check restructure to reuse common macros X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=c8eb54dbc8087c3d114cb583925395e211bfffa4;p=openwrt%2Fstaging%2Fblogic.git powerpc/64s/exception: machine check restructure to reuse common macros Follow the pattern of sreset and HMI handlers more closely: use EXCEPTION_PROLOG_COMMON_1 rather than open-coding it, and run the handler at the relocated location. This helps later simplification and code sharing. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190802105709.27696-12-npiggin@gmail.com --- diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index aa3720c0b8fe..a1f0a88d39a5 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -934,17 +934,23 @@ EXC_COMMON_BEGIN(system_reset_common) EXC_REAL_BEGIN(machine_check, 0x200, 0x100) EXCEPTION_PROLOG_0 PACA_EXMC - b machine_check_common_early + EXCEPTION_PROLOG_1 EXC_STD, PACA_EXMC, 0, 0x200, 1, 1, 0 + mfctr r10 /* save ctr, even for !RELOCATABLE */ + BRANCH_TO_C000(r11, machine_check_early_common) + /* + * MSR_RI is not enabled, because PACA_EXMC is being used, so a + * nested machine check corrupts it. machine_check_common enables + * MSR_RI. + */ EXC_REAL_END(machine_check, 0x200, 0x100) EXC_VIRT_NONE(0x4200, 0x100) -TRAMP_REAL_BEGIN(machine_check_common_early) - EXCEPTION_PROLOG_1 EXC_STD, PACA_EXMC, 0, 0x200, 0, 0, 0 + +EXC_COMMON_BEGIN(machine_check_early_common) + mtctr r10 /* Restore ctr */ + mfspr r11,SPRN_SRR0 + mfspr r12,SPRN_SRR1 + /* - * Register contents: - * R13 = PACA - * R9 = CR - * Original R9 to R13 is saved on PACA_EXMC - * * Switch to mc_emergency stack and handle re-entrancy (we limit * the nested MCE upto level 4 to avoid stack overflow). * Save MCE registers srr1, srr0, dar and dsisr and then set ME=1 @@ -965,32 +971,30 @@ TRAMP_REAL_BEGIN(machine_check_common_early) * the machine check is handled then the idle wakeup code is called * to restore state. */ - mr r11,r1 /* Save r1 */ lhz r10,PACA_IN_MCE(r13) cmpwi r10,0 /* Are we in nested machine check */ - bne 0f /* Yes, we are. */ - /* First machine check entry */ - ld r1,PACAMCEMERGSP(r13) /* Use MC emergency stack */ -0: subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */ + cmpwi cr1,r10,MAX_MCE_DEPTH /* Are we at maximum nesting */ addi r10,r10,1 /* increment paca->in_mce */ sth r10,PACA_IN_MCE(r13) + + mr r10,r1 /* Save r1 */ + bne 1f + /* First machine check entry */ + ld r1,PACAMCEMERGSP(r13) /* Use MC emergency stack */ +1: subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */ /* Limit nested MCE to level 4 to avoid stack overflow */ - cmpwi r10,MAX_MCE_DEPTH - bgt 2f /* Check if we hit limit of 4 */ - std r11,GPR1(r1) /* Save r1 on the stack. */ - std r11,0(r1) /* make stack chain pointer */ - mfspr r11,SPRN_SRR0 /* Save SRR0 */ - std r11,_NIP(r1) - mfspr r11,SPRN_SRR1 /* Save SRR1 */ - std r11,_MSR(r1) - mfspr r11,SPRN_DAR /* Save DAR */ - std r11,_DAR(r1) - mfspr r11,SPRN_DSISR /* Save DSISR */ - std r11,_DSISR(r1) - std r9,_CCR(r1) /* Save CR in stackframe */ + bge cr1,2f /* Check if we hit limit of 4 */ + + EXCEPTION_PROLOG_COMMON_1() /* We don't touch AMR here, we never go to virtual mode */ - /* Save r9 through r13 from EXMC save area to stack frame. */ EXCEPTION_PROLOG_COMMON_2(PACA_EXMC) + EXCEPTION_PROLOG_COMMON_3(0x200) + + ld r3,PACA_EXMC+EX_DAR(r13) + lwz r4,PACA_EXMC+EX_DSISR(r13) + std r3,_DAR(r1) + std r4,_DSISR(r1) + mfmsr r11 /* get MSR value */ BEGIN_FTR_SECTION ori r11,r11,MSR_ME /* turn on ME bit */ @@ -1016,8 +1020,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE) #ifdef CONFIG_PPC_PSERIES TRAMP_REAL_BEGIN(machine_check_fwnmi) + /* See comment at machine_check exception, don't turn on RI */ EXCEPTION_PROLOG_0 PACA_EXMC - b machine_check_common_early + EXCEPTION_PROLOG_1 EXC_STD, PACA_EXMC, 0, 0x200, 1, 1, 0 + mfctr r10 /* save ctr */ + BRANCH_TO_C000(r11, machine_check_early_common) #endif TRAMP_KVM_SKIP(PACA_EXMC, 0x200) @@ -1088,8 +1095,6 @@ EXC_COMMON_BEGIN(machine_check_idle_common) * ME=1, MMU (IR=0 and DR=0) off and using MC emergency stack. */ EXC_COMMON_BEGIN(machine_check_handle_early) - std r0,GPR0(r1) /* Save r0 */ - EXCEPTION_PROLOG_COMMON_3(0x200) bl save_nvgprs addi r3,r1,STACK_FRAME_OVERHEAD bl machine_check_early @@ -1180,14 +1185,10 @@ BEGIN_FTR_SECTION mtspr SPRN_CFAR,r10 END_FTR_SECTION_IFSET(CPU_FTR_CFAR) MACHINE_CHECK_HANDLER_WINDUP + /* See comment at machine_check exception, don't turn on RI */ EXCEPTION_PROLOG_0 PACA_EXMC EXCEPTION_PROLOG_1 EXC_STD, PACA_EXMC, 1, 0x200, 1, 1, 0 EXCEPTION_PROLOG_2_REAL machine_check_common, EXC_STD, 0 - /* - * MSR_RI is not enabled, because PACA_EXMC is being used, so a - * nested machine check corrupts it. machine_check_common enables - * MSR_RI. - */ EXC_COMMON_BEGIN(unrecover_mce) /* Invoke machine_check_exception to print MCE event and panic. */