diff options
Diffstat (limited to 'arch/powerpc/kernel/entry_32.S')
| -rw-r--r-- | arch/powerpc/kernel/entry_32.S | 796 |
1 files changed, 137 insertions, 659 deletions
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index 78c430b7f9d9..9160285cb2f4 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -48,195 +48,16 @@ */ .align 12 -#ifdef CONFIG_BOOKE - .globl mcheck_transfer_to_handler -mcheck_transfer_to_handler: - mfspr r0,SPRN_DSRR0 - stw r0,_DSRR0(r11) - mfspr r0,SPRN_DSRR1 - stw r0,_DSRR1(r11) - /* fall through */ -_ASM_NOKPROBE_SYMBOL(mcheck_transfer_to_handler) - - .globl debug_transfer_to_handler -debug_transfer_to_handler: - mfspr r0,SPRN_CSRR0 - stw r0,_CSRR0(r11) - mfspr r0,SPRN_CSRR1 - stw r0,_CSRR1(r11) - /* fall through */ -_ASM_NOKPROBE_SYMBOL(debug_transfer_to_handler) - - .globl crit_transfer_to_handler -crit_transfer_to_handler: -#ifdef CONFIG_PPC_BOOK3E_MMU - mfspr r0,SPRN_MAS0 - stw r0,MAS0(r11) - mfspr r0,SPRN_MAS1 - stw r0,MAS1(r11) - mfspr r0,SPRN_MAS2 - stw r0,MAS2(r11) - mfspr r0,SPRN_MAS3 - stw r0,MAS3(r11) - mfspr r0,SPRN_MAS6 - stw r0,MAS6(r11) -#ifdef CONFIG_PHYS_64BIT - mfspr r0,SPRN_MAS7 - stw r0,MAS7(r11) -#endif /* CONFIG_PHYS_64BIT */ -#endif /* CONFIG_PPC_BOOK3E_MMU */ -#ifdef CONFIG_44x - mfspr r0,SPRN_MMUCR - stw r0,MMUCR(r11) -#endif - mfspr r0,SPRN_SRR0 - stw r0,_SRR0(r11) - mfspr r0,SPRN_SRR1 - stw r0,_SRR1(r11) - - /* set the stack limit to the current stack */ - mfspr r8,SPRN_SPRG_THREAD - lwz r0,KSP_LIMIT(r8) - stw r0,SAVED_KSP_LIMIT(r11) - rlwinm r0,r1,0,0,(31 - THREAD_SHIFT) - stw r0,KSP_LIMIT(r8) - /* fall through */ -_ASM_NOKPROBE_SYMBOL(crit_transfer_to_handler) -#endif - -#ifdef CONFIG_40x - .globl crit_transfer_to_handler -crit_transfer_to_handler: - lwz r0,crit_r10@l(0) - stw r0,GPR10(r11) - lwz r0,crit_r11@l(0) - stw r0,GPR11(r11) - mfspr r0,SPRN_SRR0 - stw r0,crit_srr0@l(0) - mfspr r0,SPRN_SRR1 - stw r0,crit_srr1@l(0) - - /* set the stack limit to the current stack */ - mfspr r8,SPRN_SPRG_THREAD - lwz r0,KSP_LIMIT(r8) - stw r0,saved_ksp_limit@l(0) - rlwinm r0,r1,0,0,(31 - THREAD_SHIFT) - stw r0,KSP_LIMIT(r8) - /* fall through */ -_ASM_NOKPROBE_SYMBOL(crit_transfer_to_handler) -#endif - -/* - * This code finishes saving the registers to the exception frame - * and jumps to the appropriate handler for the exception, turning - * on address translation. - * Note that we rely on the caller having set cr0.eq iff the exception - * occurred in kernel mode (i.e. MSR:PR = 0). - */ - .globl transfer_to_handler_full -transfer_to_handler_full: - SAVE_NVGPRS(r11) -_ASM_NOKPROBE_SYMBOL(transfer_to_handler_full) - /* fall through */ - - .globl transfer_to_handler -transfer_to_handler: - stw r2,GPR2(r11) - stw r12,_NIP(r11) - stw r9,_MSR(r11) - andi. r2,r9,MSR_PR - mfctr r12 - mfspr r2,SPRN_XER - stw r12,_CTR(r11) - stw r2,_XER(r11) - mfspr r12,SPRN_SPRG_THREAD - tovirt_vmstack r12, r12 - beq 2f /* if from user, fix up THREAD.regs */ - addi r2, r12, -THREAD - addi r11,r1,STACK_FRAME_OVERHEAD - stw r11,PT_REGS(r12) -#if defined(CONFIG_40x) || defined(CONFIG_BOOKE) - /* Check to see if the dbcr0 register is set up to debug. Use the - internal debug mode bit to do this. */ - lwz r12,THREAD_DBCR0(r12) - andis. r12,r12,DBCR0_IDM@h -#endif - ACCOUNT_CPU_USER_ENTRY(r2, r11, r12) -#ifdef CONFIG_PPC_BOOK3S_32 - kuep_lock r11, r12 -#endif -#if defined(CONFIG_40x) || defined(CONFIG_BOOKE) - beq+ 3f - /* From user and task is ptraced - load up global dbcr0 */ - li r12,-1 /* clear all pending debug events */ - mtspr SPRN_DBSR,r12 - lis r11,global_dbcr0@ha - tophys(r11,r11) - addi r11,r11,global_dbcr0@l -#ifdef CONFIG_SMP - lwz r9,TASK_CPU(r2) - slwi r9,r9,2 - add r11,r11,r9 -#endif - lwz r12,0(r11) - mtspr SPRN_DBCR0,r12 -#endif - - b 3f - -2: /* if from kernel, check interrupted DOZE/NAP mode and - * check for stack overflow - */ - kuap_save_and_lock r11, r12, r9, r2, r6 - addi r2, r12, -THREAD -#ifndef CONFIG_VMAP_STACK - lwz r9,KSP_LIMIT(r12) - cmplw r1,r9 /* if r1 <= ksp_limit */ - ble- stack_ovf /* then the kernel stack overflowed */ -#endif -5: #if defined(CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500) + .globl prepare_transfer_to_handler +prepare_transfer_to_handler: + /* if from kernel, check interrupted DOZE/NAP mode */ lwz r12,TI_LOCAL_FLAGS(r2) mtcrf 0x01,r12 bt- 31-TLF_NAPPING,4f bt- 31-TLF_SLEEPING,7f -#endif /* CONFIG_PPC_BOOK3S_32 || CONFIG_E500 */ - .globl transfer_to_handler_cont -transfer_to_handler_cont: -3: - mflr r9 - tovirt_novmstack r2, r2 /* set r2 to current */ - tovirt_vmstack r9, r9 - lwz r11,0(r9) /* virtual address of handler */ - lwz r9,4(r9) /* where to go when done */ -#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS) - mtspr SPRN_NRI, r0 -#endif -#ifdef CONFIG_TRACE_IRQFLAGS - /* - * When tracing IRQ state (lockdep) we enable the MMU before we call - * the IRQ tracing functions as they might access vmalloc space or - * perform IOs for console output. - * - * To speed up the syscall path where interrupts stay on, let's check - * first if we are changing the MSR value at all. - */ - tophys_novmstack r12, r1 - lwz r12,_MSR(r12) - andi. r12,r12,MSR_EE - bne 1f - - /* MSR isn't changing, just transition directly */ -#endif - mtspr SPRN_SRR0,r11 - mtspr SPRN_SRR1,r10 - mtlr r9 - rfi /* jump to handler, enable MMU */ -#ifdef CONFIG_40x - b . /* Prevent prefetch past rfi */ -#endif + blr -#if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500) 4: rlwinm r12,r12,0,~_TLF_NAPPING stw r12,TI_LOCAL_FLAGS(r2) b power_save_ppc32_restore @@ -246,97 +67,18 @@ transfer_to_handler_cont: lwz r9,_MSR(r11) /* if sleeping, clear MSR.EE */ rlwinm r9,r9,0,~MSR_EE lwz r12,_LINK(r11) /* and return to address in LR */ - kuap_restore r11, r2, r3, r4, r5 lwz r2, GPR2(r11) b fast_exception_return -#endif -_ASM_NOKPROBE_SYMBOL(transfer_to_handler) -_ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont) - -#ifdef CONFIG_TRACE_IRQFLAGS -1: /* MSR is changing, re-enable MMU so we can notify lockdep. We need to - * keep interrupts disabled at this point otherwise we might risk - * taking an interrupt before we tell lockdep they are enabled. - */ - lis r12,reenable_mmu@h - ori r12,r12,reenable_mmu@l - LOAD_REG_IMMEDIATE(r0, MSR_KERNEL) - mtspr SPRN_SRR0,r12 - mtspr SPRN_SRR1,r0 - rfi -#ifdef CONFIG_40x - b . /* Prevent prefetch past rfi */ -#endif - -reenable_mmu: - /* - * We save a bunch of GPRs, - * r3 can be different from GPR3(r1) at this point, r9 and r11 - * contains the old MSR and handler address respectively, - * r0, r4-r8, r12, CCR, CTR, XER etc... are left - * clobbered as they aren't useful past this point. - */ - - stwu r1,-32(r1) - stw r9,8(r1) - stw r11,12(r1) - stw r3,16(r1) - - /* If we are disabling interrupts (normal case), simply log it with - * lockdep - */ -1: bl trace_hardirqs_off - lwz r3,16(r1) - lwz r11,12(r1) - lwz r9,8(r1) - addi r1,r1,32 - mtctr r11 - mtlr r9 - bctr /* jump to handler */ -#endif /* CONFIG_TRACE_IRQFLAGS */ - -#ifndef CONFIG_VMAP_STACK -/* - * On kernel stack overflow, load up an initial stack pointer - * and call StackOverflow(regs), which should not return. - */ -stack_ovf: - /* sometimes we use a statically-allocated stack, which is OK. */ - lis r12,_end@h - ori r12,r12,_end@l - cmplw r1,r12 - ble 5b /* r1 <= &_end is OK */ - SAVE_NVGPRS(r11) - addi r3,r1,STACK_FRAME_OVERHEAD - lis r1,init_thread_union@ha - addi r1,r1,init_thread_union@l - addi r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD - lis r9,StackOverflow@ha - addi r9,r9,StackOverflow@l - LOAD_REG_IMMEDIATE(r10,MSR_KERNEL) -#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS) - mtspr SPRN_NRI, r0 -#endif - mtspr SPRN_SRR0,r9 - mtspr SPRN_SRR1,r10 - rfi -#ifdef CONFIG_40x - b . /* Prevent prefetch past rfi */ -#endif -_ASM_NOKPROBE_SYMBOL(stack_ovf) -#endif +_ASM_NOKPROBE_SYMBOL(prepare_transfer_to_handler) +#endif /* CONFIG_PPC_BOOK3S_32 || CONFIG_E500 */ .globl transfer_to_syscall transfer_to_syscall: SAVE_NVGPRS(r1) -#ifdef CONFIG_PPC_BOOK3S_32 - kuep_lock r11, r12 -#endif /* Calling convention has r9 = orig r0, r10 = regs */ addi r10,r1,STACK_FRAME_OVERHEAD mr r9,r0 - stw r10,THREAD+PT_REGS(r2) bl system_call_exception ret_from_syscall: @@ -349,10 +91,6 @@ ret_from_syscall: cmplwi cr0,r5,0 bne- 2f #endif /* CONFIG_PPC_47x */ -#ifdef CONFIG_PPC_BOOK3S_32 - kuep_unlock r5, r7 -#endif - kuap_check r2, r4 lwz r4,_LINK(r1) lwz r5,_CCR(r1) mtlr r4 @@ -412,27 +150,6 @@ ret_from_kernel_thread: b ret_from_syscall /* - * Top-level page fault handling. - * This is in assembler because if do_page_fault tells us that - * it is a bad kernel page fault, we want to save the non-volatile - * registers before calling bad_page_fault. - */ - .globl handle_page_fault -handle_page_fault: - addi r3,r1,STACK_FRAME_OVERHEAD - bl do_page_fault - cmpwi r3,0 - beq+ ret_from_except - SAVE_NVGPRS(r1) - lwz r0,_TRAP(r1) - clrrwi r0,r0,1 - stw r0,_TRAP(r1) - mr r4,r3 /* err arg for bad_page_fault */ - addi r3,r1,STACK_FRAME_OVERHEAD - bl __bad_page_fault - b ret_from_except_full - -/* * This routine switches between two different tasks. The process * state of one is saved on its kernel stack. Then the state * of the other is restored from its kernel stack. The memory @@ -485,7 +202,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_SPE) stw r10,_CCR(r1) stw r1,KSP(r3) /* Set old stack pointer */ - kuap_check r2, r0 #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 @@ -529,12 +245,12 @@ END_FTR_SECTION_IFSET(CPU_FTR_SPE) fast_exception_return: #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE)) andi. r10,r9,MSR_RI /* check for recoverable interrupt */ - beq 1f /* if not, we've got problems */ + beq 3f /* if not, we've got problems */ #endif 2: REST_4GPRS(3, r11) lwz r10,_CCR(r11) - REST_GPR(1, r11) + REST_2GPRS(1, r11) mtcr r10 lwz r10,_LINK(r11) mtlr r10 @@ -556,257 +272,147 @@ fast_exception_return: #endif _ASM_NOKPROBE_SYMBOL(fast_exception_return) -#if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE)) -/* check if the exception happened in a restartable section */ -1: lis r3,exc_exit_restart_end@ha - addi r3,r3,exc_exit_restart_end@l - cmplw r12,r3 - bge 3f - lis r4,exc_exit_restart@ha - addi r4,r4,exc_exit_restart@l - cmplw r12,r4 - blt 3f - lis r3,fee_restarts@ha - tophys(r3,r3) - lwz r5,fee_restarts@l(r3) - addi r5,r5,1 - stw r5,fee_restarts@l(r3) - mr r12,r4 /* restart at exc_exit_restart */ - b 2b - - .section .bss - .align 2 -fee_restarts: - .space 4 - .previous - /* aargh, a nonrecoverable interrupt, panic */ /* aargh, we don't know which trap this is */ 3: li r10,-1 stw r10,_TRAP(r11) - addi r3,r1,STACK_FRAME_OVERHEAD - lis r10,MSR_KERNEL@h - ori r10,r10,MSR_KERNEL@l - bl transfer_to_handler_full - .long unrecoverable_exception - .long ret_from_except -#endif - - .globl ret_from_except_full -ret_from_except_full: - REST_NVGPRS(r1) - /* fall through */ - - .globl ret_from_except -ret_from_except: - /* Hard-disable interrupts so that current_thread_info()->flags - * can't change between when we test it and when we return - * from the interrupt. */ - /* Note: We don't bother telling lockdep about it */ - LOAD_REG_IMMEDIATE(r10,MSR_KERNEL) - mtmsr r10 /* disable interrupts */ - - lwz r3,_MSR(r1) /* Returning to user mode? */ - andi. r0,r3,MSR_PR - beq resume_kernel - -user_exc_return: /* r10 contains MSR_KERNEL here */ - /* Check current_thread_info()->flags */ - lwz r9,TI_FLAGS(r2) - andi. r0,r9,_TIF_USER_WORK_MASK - bne do_work + prepare_transfer_to_handler + bl unrecoverable_exception + trap /* should not get here */ -restore_user: -#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) - /* Check whether this process has its own DBCR0 value. The internal - debug mode bit tells us that dbcr0 should be loaded. */ - lwz r0,THREAD+THREAD_DBCR0(r2) - andis. r10,r0,DBCR0_IDM@h - bnel- load_dbcr0 -#endif - ACCOUNT_CPU_USER_EXIT(r2, r10, r11) -#ifdef CONFIG_PPC_BOOK3S_32 - kuep_unlock r10, r11 -#endif + .globl interrupt_return +interrupt_return: + lwz r4,_MSR(r1) + addi r3,r1,STACK_FRAME_OVERHEAD + andi. r0,r4,MSR_PR + beq .Lkernel_interrupt_return + bl interrupt_exit_user_prepare + cmpwi r3,0 + bne- .Lrestore_nvgprs - b restore +.Lfast_user_interrupt_return: + lwz r11,_NIP(r1) + lwz r12,_MSR(r1) + mtspr SPRN_SRR0,r11 + mtspr SPRN_SRR1,r12 -/* N.B. the only way to get here is from the beq following ret_from_except. */ -resume_kernel: - /* check current_thread_info, _TIF_EMULATE_STACK_STORE */ - lwz r8,TI_FLAGS(r2) - andis. r0,r8,_TIF_EMULATE_STACK_STORE@h - beq+ 1f +BEGIN_FTR_SECTION + stwcx. r0,0,r1 /* to clear the reservation */ +FTR_SECTION_ELSE + lwarx r0,0,r1 +ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) - addi r8,r1,INT_FRAME_SIZE /* Get the kprobed function entry */ + lwz r3,_CCR(r1) + lwz r4,_LINK(r1) + lwz r5,_CTR(r1) + lwz r6,_XER(r1) + li r0,0 - 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 */ + /* + * Leaving a stale exception_marker on the stack can confuse + * the reliable stack unwinder later on. Clear it. + */ + stw r0,8(r1) + REST_4GPRS(7, r1) + REST_2GPRS(11, r1) - /* Copy from the original to the trampoline. */ - li r5,INT_FRAME_SIZE/4 /* size: INT_FRAME_SIZE */ - li r6,0 /* start offset: 0 */ + mtcr r3 + mtlr r4 mtctr r5 -2: lwzx r0,r6,r4 - stwx r0,r6,r3 - addi r6,r6,4 - bdnz 2b - - /* Do real store operation to complete stwu */ - lwz r5,GPR1(r1) - stw r8,0(r5) + mtspr SPRN_XER,r6 - /* Clear _TIF_EMULATE_STACK_STORE flag */ - lis r11,_TIF_EMULATE_STACK_STORE@h - addi r5,r2,TI_FLAGS -0: lwarx r8,0,r5 - andc r8,r8,r11 - stwcx. r8,0,r5 - bne- 0b -1: - -#ifdef CONFIG_PREEMPTION - /* check current_thread_info->preempt_count */ - lwz r0,TI_PREEMPT(r2) - cmpwi 0,r0,0 /* if non-zero, just restore regs and return */ - bne restore_kuap - andi. r8,r8,_TIF_NEED_RESCHED - beq+ restore_kuap - lwz r3,_MSR(r1) - andi. r0,r3,MSR_EE /* interrupts off? */ - beq restore_kuap /* don't schedule if so */ -#ifdef CONFIG_TRACE_IRQFLAGS - /* Lockdep thinks irqs are enabled, we need to call - * preempt_schedule_irq with IRQs off, so we inform lockdep - * now that we -did- turn them off already - */ - bl trace_hardirqs_off -#endif - bl preempt_schedule_irq -#ifdef CONFIG_TRACE_IRQFLAGS - /* And now, to properly rebalance the above, we tell lockdep they - * are being turned back on, which will happen when we return - */ - bl trace_hardirqs_on + REST_4GPRS(2, r1) + REST_GPR(6, r1) + REST_GPR(0, r1) + REST_GPR(1, r1) + rfi +#ifdef CONFIG_40x + b . /* Prevent prefetch past rfi */ #endif -#endif /* CONFIG_PREEMPTION */ -restore_kuap: - kuap_restore r1, r2, r9, r10, r0 - - /* interrupts are hard-disabled at this point */ -restore: -#if defined(CONFIG_44x) && !defined(CONFIG_PPC_47x) - lis r4,icache_44x_need_flush@ha - lwz r5,icache_44x_need_flush@l(r4) - cmplwi cr0,r5,0 - beq+ 1f - li r6,0 - iccci r0,r0 - stw r6,icache_44x_need_flush@l(r4) -1: -#endif /* CONFIG_44x */ - lwz r9,_MSR(r1) -#ifdef CONFIG_TRACE_IRQFLAGS - /* Lockdep doesn't know about the fact that IRQs are temporarily turned - * off in this assembly code while peeking at TI_FLAGS() and such. However - * we need to inform it if the exception turned interrupts off, and we - * are about to trun them back on. - */ - andi. r10,r9,MSR_EE - beq 1f - stwu r1,-32(r1) - mflr r0 - stw r0,4(r1) - bl trace_hardirqs_on - addi r1, r1, 32 - lwz r9,_MSR(r1) -1: -#endif /* CONFIG_TRACE_IRQFLAGS */ +.Lrestore_nvgprs: + REST_NVGPRS(r1) + b .Lfast_user_interrupt_return - lwz r0,GPR0(r1) - lwz r2,GPR2(r1) - REST_4GPRS(3, r1) - REST_2GPRS(7, r1) +.Lkernel_interrupt_return: + bl interrupt_exit_kernel_prepare - lwz r10,_XER(r1) - lwz r11,_CTR(r1) - mtspr SPRN_XER,r10 - mtctr r11 +.Lfast_kernel_interrupt_return: + cmpwi cr1,r3,0 + lwz r11,_NIP(r1) + lwz r12,_MSR(r1) + mtspr SPRN_SRR0,r11 + mtspr SPRN_SRR1,r12 BEGIN_FTR_SECTION - lwarx r11,0,r1 -END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX) - stwcx. r0,0,r1 /* to clear the reservation */ + stwcx. r0,0,r1 /* to clear the reservation */ +FTR_SECTION_ELSE + lwarx r0,0,r1 +ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) -#if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE)) - andi. r10,r9,MSR_RI /* check if this exception occurred */ - beql nonrecoverable /* at a bad place (MSR:RI = 0) */ + lwz r3,_LINK(r1) + lwz r4,_CTR(r1) + lwz r5,_XER(r1) + lwz r6,_CCR(r1) + li r0,0 + + REST_4GPRS(7, r1) + REST_2GPRS(11, r1) - lwz r10,_CCR(r1) - lwz r11,_LINK(r1) - mtcrf 0xFF,r10 - mtlr r11 + mtlr r3 + mtctr r4 + mtspr SPRN_XER,r5 - /* Clear the exception_marker on the stack to avoid confusing stacktrace */ - li r10, 0 - stw r10, 8(r1) /* - * Once we put values in SRR0 and SRR1, we are in a state - * where exceptions are not recoverable, since taking an - * exception will trash SRR0 and SRR1. Therefore we clear the - * MSR:RI bit to indicate this. If we do take an exception, - * we can't return to the point of the exception but we - * can restart the exception exit path at the label - * exc_exit_restart below. -- paulus + * Leaving a stale exception_marker on the stack can confuse + * the reliable stack unwinder later on. Clear it. */ - LOAD_REG_IMMEDIATE(r10,MSR_KERNEL & ~MSR_RI) - mtmsr r10 /* clear the RI bit */ - .globl exc_exit_restart -exc_exit_restart: - lwz r12,_NIP(r1) - mtspr SPRN_SRR0,r12 - mtspr SPRN_SRR1,r9 - REST_4GPRS(9, r1) - lwz r1,GPR1(r1) - .globl exc_exit_restart_end -exc_exit_restart_end: + stw r0,8(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) rfi -_ASM_NOKPROBE_SYMBOL(exc_exit_restart) -_ASM_NOKPROBE_SYMBOL(exc_exit_restart_end) +#ifdef CONFIG_40x + b . /* Prevent prefetch past rfi */ +#endif -#else /* !(CONFIG_4xx || CONFIG_BOOKE) */ - /* - * This is a bit different on 4xx/Book-E because it doesn't have - * the RI bit in the MSR. - * The TLB miss handler checks if we have interrupted - * the exception exit path and restarts it if so - * (well maybe one day it will... :). +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 + * SPRG Scratch0 as temporary storage to hold the store + * data, as interrupts are disabled here so it won't be clobbered. */ - lwz r11,_LINK(r1) - mtlr r11 - lwz r10,_CCR(r1) - mtcrf 0xff,r10 - /* Clear the exception_marker on the stack to avoid confusing stacktrace */ - li r10, 0 - stw r10, 8(r1) - REST_2GPRS(9, r1) - .globl exc_exit_restart -exc_exit_restart: - lwz r11,_NIP(r1) - lwz r12,_MSR(r1) - mtspr SPRN_SRR0,r11 - mtspr SPRN_SRR1,r12 - REST_2GPRS(11, r1) - lwz r1,GPR1(r1) - .globl exc_exit_restart_end -exc_exit_restart_end: + mtcr r6 +#ifdef CONFIG_BOOKE + mtspr SPRN_SPRG_WSCRATCH0, r9 +#else + mtspr SPRN_SPRG_SCRATCH0, r9 +#endif + addi r9,r1,INT_FRAME_SIZE /* get original r1 */ + REST_GPR(6, r1) + REST_GPR(0, r1) + REST_GPR(1, r1) + stw r9,0(r1) /* perform store component of stwu */ +#ifdef CONFIG_BOOKE + mfspr r9, SPRN_SPRG_RSCRATCH0 +#else + mfspr r9, SPRN_SPRG_SCRATCH0 +#endif rfi - b . /* prevent prefetch past rfi */ -_ASM_NOKPROBE_SYMBOL(exc_exit_restart) +#ifdef CONFIG_40x + b . /* Prevent prefetch past rfi */ +#endif +_ASM_NOKPROBE_SYMBOL(interrupt_return) + +#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) /* * Returning from a critical interrupt in user mode doesn't need @@ -837,8 +443,7 @@ _ASM_NOKPROBE_SYMBOL(exc_exit_restart) REST_NVGPRS(r1); \ lwz r3,_MSR(r1); \ andi. r3,r3,MSR_PR; \ - LOAD_REG_IMMEDIATE(r10,MSR_KERNEL); \ - bne user_exc_return; \ + bne interrupt_return; \ lwz r0,GPR0(r1); \ lwz r2,GPR2(r1); \ REST_4GPRS(3, r1); \ @@ -906,11 +511,6 @@ _ASM_NOKPROBE_SYMBOL(exc_exit_restart) #ifdef CONFIG_40x .globl ret_from_crit_exc ret_from_crit_exc: - mfspr r9,SPRN_SPRG_THREAD - lis r10,saved_ksp_limit@ha; - lwz r10,saved_ksp_limit@l(r10); - tovirt(r9,r9); - stw r10,KSP_LIMIT(r9) lis r9,crit_srr0@ha; lwz r9,crit_srr0@l(r9); lis r10,crit_srr1@ha; @@ -924,9 +524,6 @@ _ASM_NOKPROBE_SYMBOL(ret_from_crit_exc) #ifdef CONFIG_BOOKE .globl ret_from_crit_exc ret_from_crit_exc: - mfspr r9,SPRN_SPRG_THREAD - lwz r10,SAVED_KSP_LIMIT(r1) - stw r10,KSP_LIMIT(r9) RESTORE_xSRR(SRR0,SRR1); RESTORE_MMU_REGS; RET_FROM_EXC_LEVEL(SPRN_CSRR0, SPRN_CSRR1, PPC_RFCI) @@ -934,9 +531,6 @@ _ASM_NOKPROBE_SYMBOL(ret_from_crit_exc) .globl ret_from_debug_exc ret_from_debug_exc: - mfspr r9,SPRN_SPRG_THREAD - lwz r10,SAVED_KSP_LIMIT(r1) - stw r10,KSP_LIMIT(r9) RESTORE_xSRR(SRR0,SRR1); RESTORE_xSRR(CSRR0,CSRR1); RESTORE_MMU_REGS; @@ -945,9 +539,6 @@ _ASM_NOKPROBE_SYMBOL(ret_from_debug_exc) .globl ret_from_mcheck_exc ret_from_mcheck_exc: - mfspr r9,SPRN_SPRG_THREAD - lwz r10,SAVED_KSP_LIMIT(r1) - stw r10,KSP_LIMIT(r9) RESTORE_xSRR(SRR0,SRR1); RESTORE_xSRR(CSRR0,CSRR1); RESTORE_xSRR(DSRR0,DSRR1); @@ -955,121 +546,8 @@ ret_from_mcheck_exc: RET_FROM_EXC_LEVEL(SPRN_MCSRR0, SPRN_MCSRR1, PPC_RFMCI) _ASM_NOKPROBE_SYMBOL(ret_from_mcheck_exc) #endif /* CONFIG_BOOKE */ - -/* - * Load the DBCR0 value for a task that is being ptraced, - * having first saved away the global DBCR0. Note that r0 - * has the dbcr0 value to set upon entry to this. - */ -load_dbcr0: - mfmsr r10 /* first disable debug exceptions */ - rlwinm r10,r10,0,~MSR_DE - mtmsr r10 - isync - mfspr r10,SPRN_DBCR0 - lis r11,global_dbcr0@ha - addi r11,r11,global_dbcr0@l -#ifdef CONFIG_SMP - lwz r9,TASK_CPU(r2) - slwi r9,r9,2 - add r11,r11,r9 -#endif - stw r10,0(r11) - mtspr SPRN_DBCR0,r0 - li r11,-1 - mtspr SPRN_DBSR,r11 /* clear all pending debug events */ - blr - - .section .bss - .align 4 - .global global_dbcr0 -global_dbcr0: - .space 4*NR_CPUS - .previous #endif /* !(CONFIG_4xx || CONFIG_BOOKE) */ -do_work: /* r10 contains MSR_KERNEL here */ - andi. r0,r9,_TIF_NEED_RESCHED - beq do_user_signal - -do_resched: /* r10 contains MSR_KERNEL here */ -#ifdef CONFIG_TRACE_IRQFLAGS - bl trace_hardirqs_on - mfmsr r10 -#endif - ori r10,r10,MSR_EE - mtmsr r10 /* hard-enable interrupts */ - bl schedule -recheck: - /* Note: And we don't tell it we are disabling them again - * neither. Those disable/enable cycles used to peek at - * TI_FLAGS aren't advertised. - */ - LOAD_REG_IMMEDIATE(r10,MSR_KERNEL) - mtmsr r10 /* disable interrupts */ - lwz r9,TI_FLAGS(r2) - andi. r0,r9,_TIF_NEED_RESCHED - bne- do_resched - andi. r0,r9,_TIF_USER_WORK_MASK - beq restore_user -do_user_signal: /* r10 contains MSR_KERNEL here */ - ori r10,r10,MSR_EE - mtmsr r10 /* hard-enable interrupts */ - /* save r13-r31 in the exception frame, if not already done */ - lwz r3,_TRAP(r1) - andi. r0,r3,1 - beq 2f - SAVE_NVGPRS(r1) - rlwinm r3,r3,0,0,30 - stw r3,_TRAP(r1) -2: addi r3,r1,STACK_FRAME_OVERHEAD - mr r4,r9 - bl do_notify_resume - REST_NVGPRS(r1) - b recheck - -/* - * We come here when we are at the end of handling an exception - * that occurred at a place where taking an exception will lose - * state information, such as the contents of SRR0 and SRR1. - */ -nonrecoverable: - lis r10,exc_exit_restart_end@ha - addi r10,r10,exc_exit_restart_end@l - cmplw r12,r10 - bge 3f - lis r11,exc_exit_restart@ha - addi r11,r11,exc_exit_restart@l - cmplw r12,r11 - blt 3f - lis r10,ee_restarts@ha - lwz r12,ee_restarts@l(r10) - addi r12,r12,1 - stw r12,ee_restarts@l(r10) - mr r12,r11 /* restart at exc_exit_restart */ - blr -3: /* OK, we can't recover, kill this process */ - lwz r3,_TRAP(r1) - andi. r0,r3,1 - beq 5f - SAVE_NVGPRS(r1) - rlwinm r3,r3,0,0,30 - stw r3,_TRAP(r1) -5: mfspr r2,SPRN_SPRG_THREAD - addi r2,r2,-THREAD - tovirt(r2,r2) /* set back r2 to current */ -4: addi r3,r1,STACK_FRAME_OVERHEAD - bl unrecoverable_exception - /* shouldn't return */ - b 4b -_ASM_NOKPROBE_SYMBOL(nonrecoverable) - - .section .bss - .align 2 -ee_restarts: - .space 4 - .previous - /* * PROM code for specific machines follows. Put it * here so it's easy to add arch-specific sections later. @@ -1088,7 +566,6 @@ _GLOBAL(enter_rtas) lis r6,1f@ha /* physical return address for rtas */ addi r6,r6,1f@l tophys(r6,r6) - tophys_novmstack r7, r1 lwz r8,RTASENTRY(r4) lwz r4,RTASBASE(r4) mfmsr r9 @@ -1097,24 +574,25 @@ _GLOBAL(enter_rtas) mtmsr r0 /* disable interrupts so SRR0/1 don't get trashed */ li r9,MSR_KERNEL & ~(MSR_IR|MSR_DR) mtlr r6 - stw r7, THREAD + RTAS_SP(r2) + stw r1, THREAD + RTAS_SP(r2) mtspr SPRN_SRR0,r8 mtspr SPRN_SRR1,r9 rfi -1: tophys_novmstack r9, r1 -#ifdef CONFIG_VMAP_STACK - li r0, MSR_KERNEL & ~MSR_IR /* can take DTLB miss */ - mtmsr r0 - isync -#endif - lwz r8,INT_FRAME_SIZE+4(r9) /* get return address */ - lwz r9,8(r9) /* original msr value */ - addi r1,r1,INT_FRAME_SIZE - li r0,0 - tophys_novmstack r7, r2 - stw r0, THREAD + RTAS_SP(r7) +1: + lis r8, 1f@h + ori r8, r8, 1f@l + LOAD_REG_IMMEDIATE(r9,MSR_KERNEL) mtspr SPRN_SRR0,r8 mtspr SPRN_SRR1,r9 - rfi /* return to caller */ + rfi /* Reactivate MMU translation */ +1: + lwz r8,INT_FRAME_SIZE+4(r1) /* get return address */ + lwz r9,8(r1) /* original msr value */ + addi r1,r1,INT_FRAME_SIZE + li r0,0 + stw r0, THREAD + RTAS_SP(r2) + mtlr r8 + mtmsr r9 + blr /* return to caller */ _ASM_NOKPROBE_SYMBOL(enter_rtas) #endif /* CONFIG_PPC_RTAS */ |