diff options
Diffstat (limited to 'arch/powerpc/kernel/entry_64.S')
| -rw-r--r-- | arch/powerpc/kernel/entry_64.S | 710 |
1 files changed, 445 insertions, 265 deletions
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 866462cbe2d..6528c5e2cc4 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -32,13 +32,15 @@ #include <asm/ptrace.h> #include <asm/irqflags.h> #include <asm/ftrace.h> +#include <asm/hw_irq.h> +#include <asm/context_tracking.h> /* * System calls. */ .section ".toc","aw" -.SYS_CALL_TABLE: - .tc .sys_call_table[TC],.sys_call_table +SYS_CALL_TABLE: + .tc sys_call_table[TC],sys_call_table /* This value is used to mark exception frames on the stack. */ exception_marker: @@ -61,16 +63,11 @@ system_call_common: std r12,_MSR(r1) std r0,GPR0(r1) std r10,GPR1(r1) + beq 2f /* if from kernel mode */ ACCOUNT_CPU_USER_ENTRY(r10, r11) - /* - * This "crclr so" clears CR0.SO, which is the error indication on - * return from this system call. There must be no cmp instruction - * between it and the "mfcr r9" below, otherwise if XER.SO is set, - * CR0.SO will get set, causing all system calls to appear to fail. - */ - crclr so - std r2,GPR2(r1) +2: std r2,GPR2(r1) std r3,GPR3(r1) + mfcr r2 std r4,GPR4(r1) std r5,GPR5(r1) std r6,GPR6(r1) @@ -81,85 +78,82 @@ system_call_common: std r11,GPR10(r1) std r11,GPR11(r1) std r11,GPR12(r1) + std r11,_XER(r1) + std r11,_CTR(r1) std r9,GPR13(r1) - mfcr r9 mflr r10 + /* + * This clears CR0.SO (bit 28), which is the error indication on + * return from this system call. + */ + rldimi r2,r11,28,(63-28) li r11,0xc01 - std r9,_CCR(r1) std r10,_LINK(r1) std r11,_TRAP(r1) - mfxer r9 - mfctr r10 - std r9,_XER(r1) - std r10,_CTR(r1) std r3,ORIG_GPR3(r1) + std r2,_CCR(r1) ld r2,PACATOC(r13) addi r9,r1,STACK_FRAME_OVERHEAD ld r11,exception_marker@toc(r2) std r11,-16(r9) /* "regshere" marker */ -#if defined(CONFIG_VIRT_CPU_ACCOUNTING) && defined(CONFIG_PPC_SPLPAR) +#if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC_SPLPAR) BEGIN_FW_FTR_SECTION beq 33f /* if from user, see if there are any DTL entries to process */ ld r10,PACALPPACAPTR(r13) /* get ptr to VPA */ ld r11,PACA_DTL_RIDX(r13) /* get log read index */ - ld r10,LPPACA_DTLIDX(r10) /* get log write index */ + addi r10,r10,LPPACA_DTLIDX + LDX_BE r10,0,r10 /* get log write index */ cmpd cr1,r11,r10 beq+ cr1,33f - bl .accumulate_stolen_time + bl accumulate_stolen_time REST_GPR(0,r1) REST_4GPRS(3,r1) REST_2GPRS(7,r1) addi r9,r1,STACK_FRAME_OVERHEAD 33: END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR) -#endif /* CONFIG_VIRT_CPU_ACCOUNTING && CONFIG_PPC_SPLPAR */ +#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE && CONFIG_PPC_SPLPAR */ -#ifdef CONFIG_TRACE_IRQFLAGS - bl .trace_hardirqs_on - REST_GPR(0,r1) - REST_4GPRS(3,r1) - REST_2GPRS(7,r1) - addi r9,r1,STACK_FRAME_OVERHEAD - ld r12,_MSR(r1) -#endif /* CONFIG_TRACE_IRQFLAGS */ - li r10,1 - stb r10,PACASOFTIRQEN(r13) - stb r10,PACAHARDIRQEN(r13) - std r10,SOFTE(r1) -#ifdef CONFIG_PPC_ISERIES -BEGIN_FW_FTR_SECTION - /* Hack for handling interrupts when soft-enabling on iSeries */ - cmpdi cr1,r0,0x5555 /* syscall 0x5555 */ - andi. r10,r12,MSR_PR /* from kernel */ - crand 4*cr0+eq,4*cr1+eq,4*cr0+eq - bne 2f - b hardware_interrupt_entry -2: -END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES) -#endif /* CONFIG_PPC_ISERIES */ + /* + * A syscall should always be called with interrupts enabled + * so we just unconditionally hard-enable here. When some kind + * of irq tracing is used, we additionally check that condition + * is correct + */ +#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_BUG) + lbz r10,PACASOFTIRQEN(r13) + xori r10,r10,1 +1: tdnei r10,0 + EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING +#endif - /* Hard enable interrupts */ #ifdef CONFIG_PPC_BOOK3E wrteei 1 #else - mfmsr r11 + ld r11,PACAKMSR(r13) ori r11,r11,MSR_EE mtmsrd r11,1 #endif /* CONFIG_PPC_BOOK3E */ + /* We do need to set SOFTE in the stack frame or the return + * from interrupt will be painful + */ + li r10,1 + std r10,SOFTE(r1) + #ifdef SHOW_SYSCALLS - bl .do_show_syscall + bl do_show_syscall REST_GPR(0,r1) REST_4GPRS(3,r1) REST_2GPRS(7,r1) addi r9,r1,STACK_FRAME_OVERHEAD #endif - clrrdi r11,r1,THREAD_SHIFT + CURRENT_THREAD_INFO(r11, r1) ld r10,TI_FLAGS(r11) andi. r11,r10,_TIF_SYSCALL_T_OR_A - bne- syscall_dotrace -syscall_dotrace_cont: + bne syscall_dotrace +.Lsyscall_dotrace_cont: cmpldi 0,r0,NR_syscalls bge- syscall_enosys @@ -168,7 +162,7 @@ system_call: /* label this so stack traces look sane */ * Need to vector to 32 Bit or default sys_call_table here, * based on caller's run-mode / personality. */ - ld r11,.SYS_CALL_TABLE@toc(2) + ld r11,SYS_CALL_TABLE@toc(2) andi. r10,r10,_TIF_32BIT beq 15f addi r11,r11,8 /* use 32-bit syscall entries */ @@ -180,17 +174,17 @@ system_call: /* label this so stack traces look sane */ clrldi r8,r8,32 15: slwi r0,r0,4 - ldx r10,r11,r0 /* Fetch system call handler [ptr] */ - mtctr r10 + ldx r12,r11,r0 /* Fetch system call handler [ptr] */ + mtctr r12 bctrl /* Call handler */ syscall_exit: std r3,RESULT(r1) #ifdef SHOW_SYSCALLS - bl .do_show_syscall_exit + bl do_show_syscall_exit ld r3,RESULT(r1) #endif - clrrdi r12,r1,THREAD_SHIFT + CURRENT_THREAD_INFO(r12, r1) ld r8,_MSR(r1) #ifdef CONFIG_PPC_BOOK3S @@ -198,17 +192,24 @@ syscall_exit: andi. r10,r8,MSR_RI beq- unrecov_restore #endif - - /* Disable interrupts so current_thread_info()->flags can't change, + /* + * Disable interrupts so current_thread_info()->flags can't change, * and so that we don't get interrupted after loading SRR0/1. */ #ifdef CONFIG_PPC_BOOK3E wrteei 0 #else - mfmsr r10 - rldicl r10,r10,48,1 - rotldi r10,r10,16 - mtmsrd r10,1 + ld r10,PACAKMSR(r13) + /* + * For performance reasons we clear RI the same time that we + * clear EE. We only need to clear RI just before we restore r13 + * below, but batching it with EE saves us one expensive mtmsrd call. + * We have to be careful to restore RI if we branch anywhere from + * here (eg syscall_exit_work). + */ + li r9,MSR_RI + andc r11,r10,r9 + mtmsrd r11,1 #endif /* CONFIG_PPC_BOOK3E */ ld r9,TI_FLAGS(r12) @@ -218,27 +219,17 @@ syscall_exit: cmpld r3,r11 ld r5,_CCR(r1) bge- syscall_error -syscall_error_cont: +.Lsyscall_error_cont: ld r7,_NIP(r1) BEGIN_FTR_SECTION stdcx. r0,0,r1 /* to clear the reservation */ END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) andi. r6,r8,MSR_PR ld r4,_LINK(r1) - /* - * Clear RI before restoring r13. If we are returning to - * userspace and we take an exception after restoring r13, - * we end up corrupting the userspace r13 value. - */ -#ifdef CONFIG_PPC_BOOK3S - /* No MSR:RI on BookE */ - li r12,MSR_RI - andc r11,r10,r12 - mtmsrd r11,1 /* clear MSR.RI */ -#endif /* CONFIG_PPC_BOOK3S */ beq- 1f ACCOUNT_CPU_USER_EXIT(r11, r12) + HMT_MEDIUM_LOW_HAS_PPR ld r13,GPR13(r1) /* only restore r13 if returning to usermode */ 1: ld r2,GPR2(r1) ld r1,GPR1(r1) @@ -253,13 +244,13 @@ syscall_error: oris r5,r5,0x1000 /* Set SO bit in CR */ neg r3,r3 std r5,_CCR(r1) - b syscall_error_cont + b .Lsyscall_error_cont /* Traced system call support */ syscall_dotrace: - bl .save_nvgprs + bl save_nvgprs addi r3,r1,STACK_FRAME_OVERHEAD - bl .do_syscall_trace_enter + bl do_syscall_trace_enter /* * Restore argument registers possibly just changed. * We use the return value of do_syscall_trace_enter @@ -273,15 +264,18 @@ syscall_dotrace: ld r7,GPR7(r1) ld r8,GPR8(r1) addi r9,r1,STACK_FRAME_OVERHEAD - clrrdi r10,r1,THREAD_SHIFT + CURRENT_THREAD_INFO(r10, r1) ld r10,TI_FLAGS(r10) - b syscall_dotrace_cont + b .Lsyscall_dotrace_cont syscall_enosys: li r3,-ENOSYS b syscall_exit syscall_exit_work: +#ifdef CONFIG_PPC_BOOK3S + mtmsrd r10,1 /* Restore RI */ +#endif /* If TIF_RESTOREALL is set, don't scribble on either r3 or ccr. If TIF_NOERROR is set, just save r3 as it is. */ @@ -312,22 +306,23 @@ syscall_exit_work: subi r12,r12,TI_FLAGS 4: /* Anything else left to do? */ + SET_DEFAULT_THREAD_PPR(r3, r10) /* Set thread.ppr = 3 */ andi. r0,r9,(_TIF_SYSCALL_T_OR_A|_TIF_SINGLESTEP) - beq .ret_from_except_lite + beq ret_from_except_lite /* Re-enable interrupts */ #ifdef CONFIG_PPC_BOOK3E wrteei 1 #else - mfmsr r10 + ld r10,PACAKMSR(r13) ori r10,r10,MSR_EE mtmsrd r10,1 #endif /* CONFIG_PPC_BOOK3E */ - bl .save_nvgprs + bl save_nvgprs addi r3,r1,STACK_FRAME_OVERHEAD - bl .do_syscall_trace_leave - b .ret_from_except + bl do_syscall_trace_leave + b ret_from_except /* Save non-volatile GPRs, if not already saved. */ _GLOBAL(save_nvgprs) @@ -350,36 +345,48 @@ _GLOBAL(save_nvgprs) */ _GLOBAL(ppc_fork) - bl .save_nvgprs - bl .sys_fork + bl save_nvgprs + bl sys_fork b syscall_exit _GLOBAL(ppc_vfork) - bl .save_nvgprs - bl .sys_vfork + bl save_nvgprs + bl sys_vfork b syscall_exit _GLOBAL(ppc_clone) - bl .save_nvgprs - bl .sys_clone + bl save_nvgprs + bl sys_clone b syscall_exit _GLOBAL(ppc32_swapcontext) - bl .save_nvgprs - bl .compat_sys_swapcontext + bl save_nvgprs + bl compat_sys_swapcontext b syscall_exit _GLOBAL(ppc64_swapcontext) - bl .save_nvgprs - bl .sys_swapcontext + bl save_nvgprs + bl sys_swapcontext b syscall_exit _GLOBAL(ret_from_fork) - bl .schedule_tail + bl schedule_tail REST_NVGPRS(r1) li r3,0 b syscall_exit +_GLOBAL(ret_from_kernel_thread) + bl schedule_tail + REST_NVGPRS(r1) + mtlr r14 + mr r3,r15 +#if defined(_CALL_ELF) && _CALL_ELF == 2 + mr r12,r14 +#endif + blrl + li r3,0 + b syscall_exit + /* * This routine switches between two different tasks. The process * state of one is saved on its kernel stack. Then the state @@ -421,12 +428,6 @@ BEGIN_FTR_SECTION std r24,THREAD_VRSAVE(r3) END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) #endif /* CONFIG_ALTIVEC */ -#ifdef CONFIG_PPC64 -BEGIN_FTR_SECTION - mfspr r25,SPRN_DSCR - std r25,THREAD_DSCR(r3) -END_FTR_SECTION_IFSET(CPU_FTR_DSCR) -#endif and. r0,r0,r22 beq+ 1f andc r22,r22,r0 @@ -437,6 +438,18 @@ END_FTR_SECTION_IFSET(CPU_FTR_DSCR) std r23,_CCR(r1) std r1,KSP(r3) /* Set old stack pointer */ +#ifdef CONFIG_PPC_BOOK3S_64 +BEGIN_FTR_SECTION + /* Event based branch registers */ + mfspr r0, SPRN_BESCR + std r0, THREAD_BESCR(r3) + mfspr r0, SPRN_EBBHR + std r0, THREAD_EBBHR(r3) + mfspr r0, SPRN_EBBRR + std r0, THREAD_EBBRR(r3) +END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) +#endif + #ifdef CONFIG_SMP /* We need a sync somewhere here to make sure that if the * previous task gets rescheduled on another CPU, it sees all @@ -456,6 +469,13 @@ BEGIN_FTR_SECTION ldarx r6,0,r1 END_FTR_SECTION_IFSET(CPU_FTR_STCX_CHECKS_ADDRESS) +#ifdef CONFIG_PPC_BOOK3S +/* Cancel all explict user streams as they will have no use after context + * switch and will stop the HW from creating streams itself + */ + DCBT_STOP_ALL_STREAM_IDS(r6) +#endif + addi r6,r4,-THREAD /* Convert THREAD to 'current' */ std r6,PACACURRENT(r13) /* Set new 'current' */ @@ -493,9 +513,11 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT) */ ld r9,PACA_SLBSHADOWPTR(r13) li r12,0 - std r12,SLBSHADOW_STACKESID(r9) /* Clear ESID */ - std r7,SLBSHADOW_STACKVSID(r9) /* Save VSID */ - std r0,SLBSHADOW_STACKESID(r9) /* Save ESID */ + std r12,SLBSHADOW_STACKESID(r9) /* Clear ESID */ + li r12,SLBSHADOW_STACKVSID + STDX_BE r7,r12,r9 /* Save VSID */ + li r12,SLBSHADOW_STACKESID + STDX_BE r0,r12,r9 /* Save ESID */ /* No need to check for MMU_FTR_NO_SLBIE_B here, since when * we have 1TB segments, the only CPUs known to have the errata @@ -510,7 +532,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT) 2: #endif /* !CONFIG_PPC_BOOK3S */ - clrrdi r7,r8,THREAD_SHIFT /* base of new stack */ + CURRENT_THREAD_INFO(r7, r8) /* base of new stack */ /* Note: this uses SWITCH_FRAME_SIZE rather than INT_FRAME_SIZE because we don't need to leave the 288-byte ABI gap at the top of the kernel stack. */ @@ -519,8 +541,20 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT) mr r1,r8 /* start using new stack pointer */ std r7,PACAKSAVE(r13) - ld r6,_CCR(r1) - mtcrf 0xFF,r6 +#ifdef CONFIG_PPC_BOOK3S_64 +BEGIN_FTR_SECTION + /* Event based branch registers */ + ld r0, THREAD_BESCR(r4) + mtspr SPRN_BESCR, r0 + ld r0, THREAD_EBBHR(r4) + mtspr SPRN_EBBHR, r0 + ld r0, THREAD_EBBRR(r4) + mtspr SPRN_EBBRR, r0 + + ld r0,THREAD_TAR(r4) + mtspr SPRN_TAR,r0 +END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) +#endif #ifdef CONFIG_ALTIVEC BEGIN_FTR_SECTION @@ -530,14 +564,27 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_PPC64 BEGIN_FTR_SECTION + lwz r6,THREAD_DSCR_INHERIT(r4) ld r0,THREAD_DSCR(r4) + cmpwi r6,0 + bne 1f + ld r0,PACA_DSCR(r13) +1: +BEGIN_FTR_SECTION_NESTED(70) + mfspr r8, SPRN_FSCR + rldimi r8, r6, FSCR_DSCR_LG, (63 - FSCR_DSCR_LG) + mtspr SPRN_FSCR, r8 +END_FTR_SECTION_NESTED(CPU_FTR_ARCH_207S, CPU_FTR_ARCH_207S, 70) cmpd r0,r25 - beq 1f + beq 2f mtspr SPRN_DSCR,r0 -1: +2: END_FTR_SECTION_IFSET(CPU_FTR_DSCR) #endif + ld r6,_CCR(r1) + mtcrf 0xFF,r6 + /* r3-r13 are destroyed -- Cort */ REST_8GPRS(14, r1) REST_10GPRS(22, r1) @@ -553,7 +600,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_DSCR) _GLOBAL(ret_from_except) ld r11,_TRAP(r1) andi. r0,r11,1 - bne .ret_from_except_lite + bne ret_from_except_lite REST_NVGPRS(r1) _GLOBAL(ret_from_except_lite) @@ -565,51 +612,197 @@ _GLOBAL(ret_from_except_lite) #ifdef CONFIG_PPC_BOOK3E wrteei 0 #else - mfmsr r10 /* Get current interrupt state */ - rldicl r9,r10,48,1 /* clear MSR_EE */ - rotldi r9,r9,16 - mtmsrd r9,1 /* Update machine state */ + ld r10,PACAKMSR(r13) /* Get kernel MSR without EE */ + mtmsrd r10,1 /* Update machine state */ #endif /* CONFIG_PPC_BOOK3E */ -#ifdef CONFIG_PREEMPT - clrrdi r9,r1,THREAD_SHIFT /* current_thread_info() */ - li r0,_TIF_NEED_RESCHED /* bits to check */ + CURRENT_THREAD_INFO(r9, r1) ld r3,_MSR(r1) +#ifdef CONFIG_PPC_BOOK3E + ld r10,PACACURRENT(r13) +#endif /* CONFIG_PPC_BOOK3E */ ld r4,TI_FLAGS(r9) - /* Move MSR_PR bit in r3 to _TIF_SIGPENDING position in r0 */ - rlwimi r0,r3,32+TIF_SIGPENDING-MSR_PR_LG,_TIF_SIGPENDING - and. r0,r4,r0 /* check NEED_RESCHED and maybe SIGPENDING */ - bne do_work - -#else /* !CONFIG_PREEMPT */ - ld r3,_MSR(r1) /* Returning to user mode? */ andi. r3,r3,MSR_PR - beq restore /* if not, just restore regs and return */ + beq resume_kernel +#ifdef CONFIG_PPC_BOOK3E + lwz r3,(THREAD+THREAD_DBCR0)(r10) +#endif /* CONFIG_PPC_BOOK3E */ /* Check current_thread_info()->flags */ - clrrdi r9,r1,THREAD_SHIFT - ld r4,TI_FLAGS(r9) andi. r0,r4,_TIF_USER_WORK_MASK - bne do_work +#ifdef CONFIG_PPC_BOOK3E + bne 1f + /* + * Check to see if the dbcr0 register is set up to debug. + * Use the internal debug mode bit to do this. + */ + andis. r0,r3,DBCR0_IDM@h + beq restore + mfmsr r0 + rlwinm r0,r0,0,~MSR_DE /* Clear MSR.DE */ + mtmsr r0 + mtspr SPRN_DBCR0,r3 + li r10, -1 + mtspr SPRN_DBSR,r10 + b restore +#else + beq restore #endif +1: andi. r0,r4,_TIF_NEED_RESCHED + beq 2f + bl restore_interrupts + SCHEDULE_USER + b ret_from_except_lite +2: +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + andi. r0,r4,_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM + bne 3f /* only restore TM if nothing else to do */ + addi r3,r1,STACK_FRAME_OVERHEAD + bl restore_tm_state + b restore +3: +#endif + bl save_nvgprs + bl restore_interrupts + addi r3,r1,STACK_FRAME_OVERHEAD + bl do_notify_resume + b ret_from_except + +resume_kernel: + /* check current_thread_info, _TIF_EMULATE_STACK_STORE */ + andis. r8,r4,_TIF_EMULATE_STACK_STORE@h + beq+ 1f + + addi r8,r1,INT_FRAME_SIZE /* Get the kprobed function entry */ + lwz r3,GPR1(r1) + subi r3,r3,INT_FRAME_SIZE /* dst: Allocate a trampoline exception frame */ + mr r4,r1 /* src: current exception frame */ + mr r1,r3 /* Reroute the trampoline frame to r1 */ + + /* Copy from the original to the trampoline. */ + li r5,INT_FRAME_SIZE/8 /* size: INT_FRAME_SIZE */ + li r6,0 /* start offset: 0 */ + mtctr r5 +2: ldx r0,r6,r4 + stdx r0,r6,r3 + addi r6,r6,8 + bdnz 2b + + /* Do real store operation to complete stwu */ + lwz r5,GPR1(r1) + std r8,0(r5) + + /* Clear _TIF_EMULATE_STACK_STORE flag */ + lis r11,_TIF_EMULATE_STACK_STORE@h + addi r5,r9,TI_FLAGS +0: ldarx r4,0,r5 + andc r4,r4,r11 + stdcx. r4,0,r5 + bne- 0b +1: + +#ifdef CONFIG_PREEMPT + /* Check if we need to preempt */ + andi. r0,r4,_TIF_NEED_RESCHED + beq+ restore + /* Check that preempt_count() == 0 and interrupts are enabled */ + lwz r8,TI_PREEMPT(r9) + cmpwi cr1,r8,0 + ld r0,SOFTE(r1) + cmpdi r0,0 + crandc eq,cr1*4+eq,eq + bne restore + + /* + * Here we are preempting the current task. We want to make + * sure we are soft-disabled first and reconcile irq state. + */ + RECONCILE_IRQ_STATE(r3,r4) +1: bl preempt_schedule_irq + + /* Re-test flags and eventually loop */ + CURRENT_THREAD_INFO(r9, r1) + ld r4,TI_FLAGS(r9) + andi. r0,r4,_TIF_NEED_RESCHED + bne 1b + + /* + * arch_local_irq_restore() from preempt_schedule_irq above may + * enable hard interrupt but we really should disable interrupts + * when we return from the interrupt, and so that we don't get + * interrupted after loading SRR0/1. + */ +#ifdef CONFIG_PPC_BOOK3E + wrteei 0 +#else + ld r10,PACAKMSR(r13) /* Get kernel MSR without EE */ + mtmsrd r10,1 /* Update machine state */ +#endif /* CONFIG_PPC_BOOK3E */ +#endif /* CONFIG_PREEMPT */ + + .globl fast_exc_return_irq +fast_exc_return_irq: restore: -BEGIN_FW_FTR_SECTION + /* + * This is the main kernel exit path. First we check if we + * are about to re-enable interrupts + */ ld r5,SOFTE(r1) -FW_FTR_SECTION_ELSE - b .Liseries_check_pending_irqs -ALT_FW_FTR_SECTION_END_IFCLR(FW_FEATURE_ISERIES) -2: - TRACE_AND_RESTORE_IRQ(r5); + lbz r6,PACASOFTIRQEN(r13) + cmpwi cr0,r5,0 + beq restore_irq_off - /* extract EE bit and use it to restore paca->hard_enabled */ - ld r3,_MSR(r1) - rldicl r4,r3,49,63 /* r0 = (r3 >> 15) & 1 */ - stb r4,PACAHARDIRQEN(r13) + /* We are enabling, were we already enabled ? Yes, just return */ + cmpwi cr0,r6,1 + beq cr0,do_restore + /* + * We are about to soft-enable interrupts (we are hard disabled + * at this point). We check if there's anything that needs to + * be replayed first. + */ + lbz r0,PACAIRQHAPPENED(r13) + cmpwi cr0,r0,0 + bne- restore_check_irq_replay + + /* + * Get here when nothing happened while soft-disabled, just + * soft-enable and move-on. We will hard-enable as a side + * effect of rfi + */ +restore_no_replay: + TRACE_ENABLE_INTS + li r0,1 + stb r0,PACASOFTIRQEN(r13); + + /* + * Final return path. BookE is handled in a different file + */ +do_restore: #ifdef CONFIG_PPC_BOOK3E - b .exception_return_book3e + b exception_return_book3e #else + /* + * Clear the reservation. If we know the CPU tracks the address of + * the reservation then we can potentially save some cycles and use + * a larx. On POWER6 and POWER7 this is significantly faster. + */ +BEGIN_FTR_SECTION + stdcx. r0,0,r1 /* to clear the reservation */ +FTR_SECTION_ELSE + ldarx r4,0,r1 +ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) + + /* + * Some code path such as load_up_fpu or altivec return directly + * here. They run entirely hard disabled and do not alter the + * interrupt state. They also don't use lwarx/stwcx. and thus + * are known not to leave dangling reservations. + */ + .globl fast_exception_return +fast_exception_return: + ld r3,_MSR(r1) ld r4,_CTR(r1) ld r0,_LINK(r1) mtctr r4 @@ -622,32 +815,35 @@ ALT_FW_FTR_SECTION_END_IFCLR(FW_FEATURE_ISERIES) andi. r0,r3,MSR_RI beq- unrecov_restore - /* - * Clear the reservation. If we know the CPU tracks the address of - * the reservation then we can potentially save some cycles and use - * a larx. On POWER6 and POWER7 this is significantly faster. - */ + /* Load PPR from thread struct before we clear MSR:RI */ BEGIN_FTR_SECTION - stdcx. r0,0,r1 /* to clear the reservation */ -FTR_SECTION_ELSE - ldarx r4,0,r1 -ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) + ld r2,PACACURRENT(r13) + ld r2,TASKTHREADPPR(r2) +END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) /* * Clear RI before restoring r13. If we are returning to * userspace and we take an exception after restoring r13, * we end up corrupting the userspace r13 value. */ - mfmsr r4 - andc r4,r4,r0 /* r0 contains MSR_RI here */ + ld r4,PACAKMSR(r13) /* Get kernel MSR without EE */ + andc r4,r4,r0 /* r0 contains MSR_RI here */ mtmsrd r4,1 +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + /* TM debug */ + std r3, PACATMSCRATCH(r13) /* Stash returned-to MSR */ +#endif /* * r13 is our per cpu area, only restore it if we are returning to - * userspace + * userspace the value stored in the stack frame may belong to + * another CPU. */ andi. r0,r3,MSR_PR beq 1f +BEGIN_FTR_SECTION + mtspr SPRN_PPR,r2 /* Restore PPR */ +END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ACCOUNT_CPU_USER_EXIT(r2, r4) REST_GPR(13, r1) 1: @@ -669,103 +865,86 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) #endif /* CONFIG_PPC_BOOK3E */ -.Liseries_check_pending_irqs: -#ifdef CONFIG_PPC_ISERIES - ld r5,SOFTE(r1) - cmpdi 0,r5,0 - beq 2b - /* Check for pending interrupts (iSeries) */ - ld r3,PACALPPACAPTR(r13) - ld r3,LPPACAANYINT(r3) - cmpdi r3,0 - beq+ 2b /* skip do_IRQ if no interrupts */ - - li r3,0 - stb r3,PACASOFTIRQEN(r13) /* ensure we are soft-disabled */ -#ifdef CONFIG_TRACE_IRQFLAGS - bl .trace_hardirqs_off - mfmsr r10 -#endif - ori r10,r10,MSR_EE - mtmsrd r10 /* hard-enable again */ - addi r3,r1,STACK_FRAME_OVERHEAD - bl .do_IRQ - b .ret_from_except_lite /* loop back and handle more */ -#endif - -do_work: -#ifdef CONFIG_PREEMPT - andi. r0,r3,MSR_PR /* Returning to user mode? */ - bne user_work - /* Check that preempt_count() == 0 and interrupts are enabled */ - lwz r8,TI_PREEMPT(r9) - cmpwi cr1,r8,0 - ld r0,SOFTE(r1) - cmpdi r0,0 - crandc eq,cr1*4+eq,eq - bne restore - - /* Here we are preempting the current task. + /* + * We are returning to a context with interrupts soft disabled. * - * Ensure interrupts are soft-disabled. We also properly mark - * the PACA to reflect the fact that they are hard-disabled - * and trace the change + * However, we may also about to hard enable, so we need to + * make sure that in this case, we also clear PACA_IRQ_HARD_DIS + * or that bit can get out of sync and bad things will happen */ - li r0,0 - stb r0,PACASOFTIRQEN(r13) - stb r0,PACAHARDIRQEN(r13) +restore_irq_off: + ld r3,_MSR(r1) + lbz r7,PACAIRQHAPPENED(r13) + andi. r0,r3,MSR_EE + beq 1f + rlwinm r7,r7,0,~PACA_IRQ_HARD_DIS + stb r7,PACAIRQHAPPENED(r13) +1: li r0,0 + stb r0,PACASOFTIRQEN(r13); TRACE_DISABLE_INTS + b do_restore - /* Call the scheduler with soft IRQs off */ -1: bl .preempt_schedule_irq - - /* Hard-disable interrupts again (and update PACA) */ -#ifdef CONFIG_PPC_BOOK3E - wrteei 0 -#else - mfmsr r10 - rldicl r10,r10,48,1 - rotldi r10,r10,16 - mtmsrd r10,1 -#endif /* CONFIG_PPC_BOOK3E */ - li r0,0 - stb r0,PACAHARDIRQEN(r13) - - /* Re-test flags and eventually loop */ - clrrdi r9,r1,THREAD_SHIFT - ld r4,TI_FLAGS(r9) - andi. r0,r4,_TIF_NEED_RESCHED - bne 1b - b restore - -user_work: -#endif /* CONFIG_PREEMPT */ + /* + * Something did happen, check if a re-emit is needed + * (this also clears paca->irq_happened) + */ +restore_check_irq_replay: + /* XXX: We could implement a fast path here where we check + * for irq_happened being just 0x01, in which case we can + * clear it and return. That means that we would potentially + * miss a decrementer having wrapped all the way around. + * + * Still, this might be useful for things like hash_page + */ + bl __check_irq_replay + cmpwi cr0,r3,0 + beq restore_no_replay + + /* + * We need to re-emit an interrupt. We do so by re-using our + * existing exception frame. We first change the trap value, + * but we need to ensure we preserve the low nibble of it + */ + ld r4,_TRAP(r1) + clrldi r4,r4,60 + or r4,r4,r3 + std r4,_TRAP(r1) - /* Enable interrupts */ + /* + * Then find the right handler and call it. Interrupts are + * still soft-disabled and we keep them that way. + */ + cmpwi cr0,r3,0x500 + bne 1f + addi r3,r1,STACK_FRAME_OVERHEAD; + bl do_IRQ + b ret_from_except +1: cmpwi cr0,r3,0x900 + bne 1f + addi r3,r1,STACK_FRAME_OVERHEAD; + bl timer_interrupt + b ret_from_except +#ifdef CONFIG_PPC_DOORBELL +1: #ifdef CONFIG_PPC_BOOK3E - wrteei 1 + cmpwi cr0,r3,0x280 #else - ori r10,r10,MSR_EE - mtmsrd r10,1 + BEGIN_FTR_SECTION + cmpwi cr0,r3,0xe80 + FTR_SECTION_ELSE + cmpwi cr0,r3,0xa00 + ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE) #endif /* CONFIG_PPC_BOOK3E */ - - andi. r0,r4,_TIF_NEED_RESCHED - beq 1f - li r5,1 - TRACE_AND_RESTORE_IRQ(r5); - bl .schedule - b .ret_from_except_lite - -1: bl .save_nvgprs - li r5,1 - TRACE_AND_RESTORE_IRQ(r5); - addi r3,r1,STACK_FRAME_OVERHEAD - bl .do_notify_resume - b .ret_from_except - + bne 1f + addi r3,r1,STACK_FRAME_OVERHEAD; + bl doorbell_exception + b ret_from_except +#endif /* CONFIG_PPC_DOORBELL */ +1: b ret_from_except /* What else to do here ? */ + unrecov_restore: addi r3,r1,STACK_FRAME_OVERHEAD - bl .unrecoverable_exception + bl unrecoverable_exception b unrecov_restore #ifdef CONFIG_PPC_RTAS @@ -831,7 +1010,7 @@ _GLOBAL(enter_rtas) std r6,PACASAVEDMSR(r13) /* Setup our real return addr */ - LOAD_REG_ADDR(r4,.rtas_return_loc) + LOAD_REG_ADDR(r4,rtas_return_loc) clrldi r4,r4,2 /* convert to realmode address */ mtlr r4 @@ -841,7 +1020,7 @@ _GLOBAL(enter_rtas) li r9,1 rldicr r9,r9,MSR_SF_LG,(63-MSR_SF_LG) - ori r9,r9,MSR_IR|MSR_DR|MSR_FE0|MSR_FE1|MSR_FP|MSR_RI + ori r9,r9,MSR_IR|MSR_DR|MSR_FE0|MSR_FE1|MSR_FP|MSR_RI|MSR_LE andc r6,r0,r9 sync /* disable interrupts so SRR0/1 */ mtmsrd r0 /* don't get trashed */ @@ -855,14 +1034,16 @@ _GLOBAL(enter_rtas) rfid b . /* prevent speculative execution */ -_STATIC(rtas_return_loc) +rtas_return_loc: + FIXUP_ENDIAN + /* relocation is off at this point */ GET_PACA(r4) clrldi r4,r4,2 /* convert to realmode address */ bcl 20,31,$+4 0: mflr r3 - ld r3,(1f-0b)(r3) /* get &.rtas_restore_regs */ + ld r3,(1f-0b)(r3) /* get &rtas_restore_regs */ mfmsr r6 li r0,MSR_RI @@ -879,9 +1060,9 @@ _STATIC(rtas_return_loc) b . /* prevent speculative execution */ .align 3 -1: .llong .rtas_restore_regs +1: .llong rtas_restore_regs -_STATIC(rtas_restore_regs) +rtas_restore_regs: /* relocation is on at this point */ REST_GPR(2, r1) /* Restore the TOC */ REST_GPR(13, r1) /* Restore paca */ @@ -927,28 +1108,30 @@ _GLOBAL(enter_prom) std r10,_CCR(r1) std r11,_MSR(r1) - /* Get the PROM entrypoint */ - mtlr r4 + /* Put PROM address in SRR0 */ + mtsrr0 r4 - /* Switch MSR to 32 bits mode + /* Setup our trampoline return addr in LR */ + bcl 20,31,$+4 +0: mflr r4 + addi r4,r4,(1f - 0b) + mtlr r4 + + /* Prepare a 32-bit mode big endian MSR */ #ifdef CONFIG_PPC_BOOK3E rlwinm r11,r11,0,1,31 - mtmsr r11 + mtsrr1 r11 + rfi #else /* CONFIG_PPC_BOOK3E */ - mfmsr r11 - li r12,1 - rldicr r12,r12,MSR_SF_LG,(63-MSR_SF_LG) - andc r11,r11,r12 - li r12,1 - rldicr r12,r12,MSR_ISF_LG,(63-MSR_ISF_LG) - andc r11,r11,r12 - mtmsrd r11 + LOAD_REG_IMMEDIATE(r12, MSR_SF | MSR_ISF | MSR_LE) + andc r11,r11,r12 + mtsrr1 r11 + rfid #endif /* CONFIG_PPC_BOOK3E */ - isync - /* Enter PROM here... */ - blrl +1: /* Return from OF */ + FIXUP_ENDIAN /* Just make sure that r1 top 32 bits didn't get * corrupt by OF @@ -979,7 +1162,7 @@ _GLOBAL(mcount) _GLOBAL(_mcount) blr -_GLOBAL(ftrace_caller) +_GLOBAL_TOC(ftrace_caller) /* Taken from output of objdump from lib64/glibc */ mflr r3 ld r11, 0(r1) @@ -1003,10 +1186,7 @@ _GLOBAL(ftrace_graph_stub) _GLOBAL(ftrace_stub) blr #else -_GLOBAL(mcount) - blr - -_GLOBAL(_mcount) +_GLOBAL_TOC(_mcount) /* Taken from output of objdump from lib64/glibc */ mflr r3 ld r11, 0(r1) @@ -1044,7 +1224,7 @@ _GLOBAL(ftrace_graph_caller) ld r11, 112(r1) addi r3, r11, 16 - bl .prepare_ftrace_return + bl prepare_ftrace_return nop ld r0, 128(r1) @@ -1060,7 +1240,7 @@ _GLOBAL(return_to_handler) mr r31, r1 stdu r1, -112(r1) - bl .ftrace_return_to_handler + bl ftrace_return_to_handler nop /* return value has real return address */ @@ -1090,7 +1270,7 @@ _GLOBAL(mod_return_to_handler) */ ld r2, PACATOC(r13) - bl .ftrace_return_to_handler + bl ftrace_return_to_handler nop /* return value has real return address */ |