diff options
Diffstat (limited to 'arch/powerpc/kernel/entry_64.S')
| -rw-r--r-- | arch/powerpc/kernel/entry_64.S | 1284 |
1 files changed, 0 insertions, 1284 deletions
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S deleted file mode 100644 index ab15b8d057ad..000000000000 --- a/arch/powerpc/kernel/entry_64.S +++ /dev/null @@ -1,1284 +0,0 @@ -/* - * PowerPC version - * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) - * Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP - * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu> - * Adapted for Power Macintosh by Paul Mackerras. - * Low-level exception handlers and MMU support - * rewritten by Paul Mackerras. - * Copyright (C) 1996 Paul Mackerras. - * MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net). - * - * This file contains the system call entry code, context switch - * code, and exception/interrupt return code for PowerPC. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - */ - -#include <linux/errno.h> -#include <asm/unistd.h> -#include <asm/processor.h> -#include <asm/page.h> -#include <asm/mmu.h> -#include <asm/thread_info.h> -#include <asm/ppc_asm.h> -#include <asm/asm-offsets.h> -#include <asm/cputable.h> -#include <asm/firmware.h> -#include <asm/bug.h> -#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 - -/* This value is used to mark exception frames on the stack. */ -exception_marker: - .tc ID_EXC_MARKER[TC],STACK_FRAME_REGS_MARKER - - .section ".text" - .align 7 - -#undef SHOW_SYSCALLS - - .globl system_call_common -system_call_common: - andi. r10,r12,MSR_PR - mr r10,r1 - addi r1,r1,-INT_FRAME_SIZE - beq- 1f - ld r1,PACAKSAVE(r13) -1: std r10,0(r1) - std r11,_NIP(r1) - std r12,_MSR(r1) - std r0,GPR0(r1) - std r10,GPR1(r1) - beq 2f /* if from kernel mode */ - ACCOUNT_CPU_USER_ENTRY(r10, r11) -2: std r2,GPR2(r1) - std r3,GPR3(r1) - mfcr r2 - std r4,GPR4(r1) - std r5,GPR5(r1) - std r6,GPR6(r1) - std r7,GPR7(r1) - std r8,GPR8(r1) - li r11,0 - std r11,GPR9(r1) - std r11,GPR10(r1) - std r11,GPR11(r1) - std r11,GPR12(r1) - std r11,_XER(r1) - std r11,_CTR(r1) - std r9,GPR13(r1) - 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 r10,_LINK(r1) - std r11,_TRAP(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_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 */ - cmpd cr1,r11,r10 - beq+ cr1,33f - 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_NATIVE && CONFIG_PPC_SPLPAR */ - - /* - * 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 - -#ifdef CONFIG_PPC_BOOK3E - wrteei 1 -#else - 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 - REST_GPR(0,r1) - REST_4GPRS(3,r1) - REST_2GPRS(7,r1) - addi r9,r1,STACK_FRAME_OVERHEAD -#endif - CURRENT_THREAD_INFO(r11, r1) - ld r10,TI_FLAGS(r11) - andi. r11,r10,_TIF_SYSCALL_T_OR_A - bne syscall_dotrace -.Lsyscall_dotrace_cont: - cmpldi 0,r0,NR_syscalls - bge- syscall_enosys - -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) - andi. r10,r10,_TIF_32BIT - beq 15f - addi r11,r11,8 /* use 32-bit syscall entries */ - clrldi r3,r3,32 - clrldi r4,r4,32 - clrldi r5,r5,32 - clrldi r6,r6,32 - clrldi r7,r7,32 - clrldi r8,r8,32 -15: - slwi r0,r0,4 - ldx r10,r11,r0 /* Fetch system call handler [ptr] */ - mtctr r10 - bctrl /* Call handler */ - -syscall_exit: - std r3,RESULT(r1) -#ifdef SHOW_SYSCALLS - bl .do_show_syscall_exit - ld r3,RESULT(r1) -#endif - CURRENT_THREAD_INFO(r12, r1) - - ld r8,_MSR(r1) -#ifdef CONFIG_PPC_BOOK3S - /* No MSR:RI on BookE */ - andi. r10,r8,MSR_RI - beq- unrecov_restore -#endif - /* - * 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 - 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) - li r11,-_LAST_ERRNO - andi. r0,r9,(_TIF_SYSCALL_T_OR_A|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK) - bne- syscall_exit_work - cmpld r3,r11 - ld r5,_CCR(r1) - bge- syscall_error -.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) - - 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) - mtlr r4 - mtcr r5 - mtspr SPRN_SRR0,r7 - mtspr SPRN_SRR1,r8 - RFI - b . /* prevent speculative execution */ - -syscall_error: - oris r5,r5,0x1000 /* Set SO bit in CR */ - neg r3,r3 - std r5,_CCR(r1) - b .Lsyscall_error_cont - -/* Traced system call support */ -syscall_dotrace: - bl .save_nvgprs - addi r3,r1,STACK_FRAME_OVERHEAD - bl .do_syscall_trace_enter - /* - * Restore argument registers possibly just changed. - * We use the return value of do_syscall_trace_enter - * for the call number to look up in the table (r0). - */ - mr r0,r3 - ld r3,GPR3(r1) - ld r4,GPR4(r1) - ld r5,GPR5(r1) - ld r6,GPR6(r1) - ld r7,GPR7(r1) - ld r8,GPR8(r1) - addi r9,r1,STACK_FRAME_OVERHEAD - CURRENT_THREAD_INFO(r10, r1) - ld r10,TI_FLAGS(r10) - 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. */ - - andi. r0,r9,_TIF_RESTOREALL - beq+ 0f - REST_NVGPRS(r1) - b 2f -0: cmpld r3,r11 /* r10 is -LAST_ERRNO */ - blt+ 1f - andi. r0,r9,_TIF_NOERROR - bne- 1f - ld r5,_CCR(r1) - neg r3,r3 - oris r5,r5,0x1000 /* Set SO bit in CR */ - std r5,_CCR(r1) -1: std r3,GPR3(r1) -2: andi. r0,r9,(_TIF_PERSYSCALL_MASK) - beq 4f - - /* Clear per-syscall TIF flags if any are set. */ - - li r11,_TIF_PERSYSCALL_MASK - addi r12,r12,TI_FLAGS -3: ldarx r10,0,r12 - andc r10,r10,r11 - stdcx. r10,0,r12 - bne- 3b - 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 - - /* Re-enable interrupts */ -#ifdef CONFIG_PPC_BOOK3E - wrteei 1 -#else - ld r10,PACAKMSR(r13) - ori r10,r10,MSR_EE - mtmsrd r10,1 -#endif /* CONFIG_PPC_BOOK3E */ - - bl .save_nvgprs - addi r3,r1,STACK_FRAME_OVERHEAD - bl .do_syscall_trace_leave - b .ret_from_except - -/* Save non-volatile GPRs, if not already saved. */ -_GLOBAL(save_nvgprs) - ld r11,_TRAP(r1) - andi. r0,r11,1 - beqlr- - SAVE_NVGPRS(r1) - clrrdi r0,r11,1 - std r0,_TRAP(r1) - blr - - -/* - * The sigsuspend and rt_sigsuspend system calls can call do_signal - * and thus put the process into the stopped state where we might - * want to examine its user state with ptrace. Therefore we need - * to save all the nonvolatile registers (r14 - r31) before calling - * the C code. Similarly, fork, vfork and clone need the full - * register state on the stack so that it can be copied to the child. - */ - -_GLOBAL(ppc_fork) - bl .save_nvgprs - bl .sys_fork - b syscall_exit - -_GLOBAL(ppc_vfork) - bl .save_nvgprs - bl .sys_vfork - b syscall_exit - -_GLOBAL(ppc_clone) - bl .save_nvgprs - bl .sys_clone - b syscall_exit - -_GLOBAL(ppc32_swapcontext) - bl .save_nvgprs - bl .compat_sys_swapcontext - b syscall_exit - -_GLOBAL(ppc64_swapcontext) - bl .save_nvgprs - bl .sys_swapcontext - b syscall_exit - -_GLOBAL(ret_from_fork) - bl .schedule_tail - REST_NVGPRS(r1) - li r3,0 - b syscall_exit - -_GLOBAL(ret_from_kernel_thread) - bl .schedule_tail - REST_NVGPRS(r1) - ld r14, 0(r14) - mtlr r14 - mr r3,r15 - blrl - li r3,0 - b syscall_exit - - .section ".toc","aw" -DSCR_DEFAULT: - .tc dscr_default[TC],dscr_default - - .section ".text" - -/* - * 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 - * management hardware is updated to the second process's state. - * Finally, we can return to the second process, via ret_from_except. - * On entry, r3 points to the THREAD for the current task, r4 - * points to the THREAD for the new task. - * - * Note: there are two ways to get to the "going out" portion - * of this code; either by coming in via the entry (_switch) - * or via "fork" which must set up an environment equivalent - * to the "_switch" path. If you change this you'll have to change - * the fork code also. - * - * The code which creates the new task context is in 'copy_thread' - * in arch/powerpc/kernel/process.c - */ - .align 7 -_GLOBAL(_switch) - mflr r0 - std r0,16(r1) - stdu r1,-SWITCH_FRAME_SIZE(r1) - /* r3-r13 are caller saved -- Cort */ - SAVE_8GPRS(14, r1) - SAVE_10GPRS(22, r1) - mflr r20 /* Return to switch caller */ - mfmsr r22 - li r0, MSR_FP -#ifdef CONFIG_VSX -BEGIN_FTR_SECTION - oris r0,r0,MSR_VSX@h /* Disable VSX */ -END_FTR_SECTION_IFSET(CPU_FTR_VSX) -#endif /* CONFIG_VSX */ -#ifdef CONFIG_ALTIVEC -BEGIN_FTR_SECTION - oris r0,r0,MSR_VEC@h /* Disable altivec */ - mfspr r24,SPRN_VRSAVE /* save vrsave register value */ - 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 - MTMSRD(r22) - isync -1: std r20,_NIP(r1) - mfcr r23 - std r23,_CCR(r1) - std r1,KSP(r3) /* Set old stack pointer */ - -#ifdef CONFIG_PPC_BOOK3S_64 -BEGIN_FTR_SECTION - /* - * Back up the TAR across context switches. Note that the TAR is not - * available for use in the kernel. (To provide this, the TAR should - * be backed up/restored on exception entry/exit instead, and be in - * pt_regs. FIXME, this should be in pt_regs anyway (for debug).) - */ - mfspr r0,SPRN_TAR - std r0,THREAD_TAR(r3) - - /* 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 - * stores it has performed on this one. - */ - sync -#endif /* CONFIG_SMP */ - - /* - * If we optimise away the clear of the reservation in system - * calls because we know the CPU tracks the address of the - * reservation, then we need to clear it here to cover the - * case that the kernel context switch path has no larx - * instructions. - */ -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' */ - - ld r8,KSP(r4) /* new stack pointer */ -#ifdef CONFIG_PPC_BOOK3S -BEGIN_FTR_SECTION - BEGIN_FTR_SECTION_NESTED(95) - clrrdi r6,r8,28 /* get its ESID */ - clrrdi r9,r1,28 /* get current sp ESID */ - FTR_SECTION_ELSE_NESTED(95) - clrrdi r6,r8,40 /* get its 1T ESID */ - clrrdi r9,r1,40 /* get current sp 1T ESID */ - ALT_MMU_FTR_SECTION_END_NESTED_IFCLR(MMU_FTR_1T_SEGMENT, 95) -FTR_SECTION_ELSE - b 2f -ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_SLB) - clrldi. r0,r6,2 /* is new ESID c00000000? */ - cmpd cr1,r6,r9 /* or is new ESID the same as current ESID? */ - cror eq,4*cr1+eq,eq - beq 2f /* if yes, don't slbie it */ - - /* Bolt in the new stack SLB entry */ - ld r7,KSP_VSID(r4) /* Get new stack's VSID */ - oris r0,r6,(SLB_ESID_V)@h - ori r0,r0,(SLB_NUM_BOLTED-1)@l -BEGIN_FTR_SECTION - li r9,MMU_SEGSIZE_1T /* insert B field */ - oris r6,r6,(MMU_SEGSIZE_1T << SLBIE_SSIZE_SHIFT)@h - rldimi r7,r9,SLB_VSID_SSIZE_SHIFT,0 -END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT) - - /* Update the last bolted SLB. No write barriers are needed - * here, provided we only update the current CPU's SLB shadow - * buffer. - */ - 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 */ - - /* 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 - * only support less than 1TB of system memory and we'll never - * actually hit this code path. - */ - - slbie r6 - slbie r6 /* Workaround POWER5 < DD2.1 issue */ - slbmte r7,r0 - isync -2: -#endif /* !CONFIG_PPC_BOOK3S */ - - 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. */ - addi r7,r7,THREAD_SIZE-SWITCH_FRAME_SIZE - - mr r1,r8 /* start using new stack pointer */ - std r7,PACAKSAVE(r13) - -#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 - ld r0,THREAD_VRSAVE(r4) - mtspr SPRN_VRSAVE,r0 /* if G4, restore VRSAVE reg */ -END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) -#endif /* CONFIG_ALTIVEC */ -#ifdef CONFIG_PPC64 -BEGIN_FTR_SECTION - lwz r6,THREAD_DSCR_INHERIT(r4) - ld r7,DSCR_DEFAULT@toc(2) - ld r0,THREAD_DSCR(r4) - cmpwi r6,0 - bne 1f - ld r0,0(r7) -1: cmpd r0,r25 - beq 2f - mtspr SPRN_DSCR,r0 -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) - - /* convert old thread to its task_struct for return value */ - addi r3,r3,-THREAD - ld r7,_NIP(r1) /* Return to _switch caller in new task */ - mtlr r7 - addi r1,r1,SWITCH_FRAME_SIZE - blr - - .align 7 -_GLOBAL(ret_from_except) - ld r11,_TRAP(r1) - andi. r0,r11,1 - bne .ret_from_except_lite - REST_NVGPRS(r1) - -_GLOBAL(ret_from_except_lite) - /* - * Disable interrupts so that current_thread_info()->flags - * can't change between when we test it and when we return - * from the interrupt. - */ -#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 */ - - 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) - andi. r3,r3,MSR_PR - beq resume_kernel -#ifdef CONFIG_PPC_BOOK3E - lwz r3,(THREAD+THREAD_DBCR0)(r10) -#endif /* CONFIG_PPC_BOOK3E */ - - /* Check current_thread_info()->flags */ - andi. r0,r4,_TIF_USER_WORK_MASK -#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: 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 */ - CURRENT_THREAD_INFO(r9, r1) - ld r8,TI_FLAGS(r9) - andis. r8,r8,_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 - */ - SOFT_DISABLE_INTS(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: - /* - * This is the main kernel exit path. First we check if we - * are about to re-enable interrupts - */ - ld r5,SOFTE(r1) - lbz r6,PACASOFTIRQEN(r13) - cmpwi cr0,r5,0 - beq restore_irq_off - - /* 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 -#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 - mtlr r0 - ld r4,_XER(r1) - mtspr SPRN_XER,r4 - - REST_8GPRS(5, r1) - - andi. r0,r3,MSR_RI - beq- unrecov_restore - - /* - * 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. - */ - 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 the value stored in the stack frame may belong to - * another CPU. - */ - andi. r0,r3,MSR_PR - beq 1f - ACCOUNT_CPU_USER_EXIT(r2, r4) - RESTORE_PPR(r2, r4) - REST_GPR(13, r1) -1: - mtspr SPRN_SRR1,r3 - - ld r2,_CCR(r1) - mtcrf 0xFF,r2 - ld r2,_NIP(r1) - mtspr SPRN_SRR0,r2 - - ld r0,GPR0(r1) - ld r2,GPR2(r1) - ld r3,GPR3(r1) - ld r4,GPR4(r1) - ld r1,GPR1(r1) - - rfid - b . /* prevent speculative execution */ - -#endif /* CONFIG_PPC_BOOK3E */ - - /* - * We are returning to a context with interrupts soft disabled. - * - * 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 - */ -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 - - /* - * 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) - - /* - * 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 - cmpwi cr0,r3,0x280 -#else - 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 */ - 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 - b unrecov_restore - -#ifdef CONFIG_PPC_RTAS -/* - * On CHRP, the Run-Time Abstraction Services (RTAS) have to be - * called with the MMU off. - * - * In addition, we need to be in 32b mode, at least for now. - * - * Note: r3 is an input parameter to rtas, so don't trash it... - */ -_GLOBAL(enter_rtas) - mflr r0 - std r0,16(r1) - stdu r1,-RTAS_FRAME_SIZE(r1) /* Save SP and create stack space. */ - - /* Because RTAS is running in 32b mode, it clobbers the high order half - * of all registers that it saves. We therefore save those registers - * RTAS might touch to the stack. (r0, r3-r13 are caller saved) - */ - SAVE_GPR(2, r1) /* Save the TOC */ - SAVE_GPR(13, r1) /* Save paca */ - SAVE_8GPRS(14, r1) /* Save the non-volatiles */ - SAVE_10GPRS(22, r1) /* ditto */ - - mfcr r4 - std r4,_CCR(r1) - mfctr r5 - std r5,_CTR(r1) - mfspr r6,SPRN_XER - std r6,_XER(r1) - mfdar r7 - std r7,_DAR(r1) - mfdsisr r8 - std r8,_DSISR(r1) - - /* Temporary workaround to clear CR until RTAS can be modified to - * ignore all bits. - */ - li r0,0 - mtcr r0 - -#ifdef CONFIG_BUG - /* There is no way it is acceptable to get here with interrupts enabled, - * check it with the asm equivalent of WARN_ON - */ - lbz r0,PACASOFTIRQEN(r13) -1: tdnei r0,0 - EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING -#endif - - /* Hard-disable interrupts */ - mfmsr r6 - rldicl r7,r6,48,1 - rotldi r7,r7,16 - mtmsrd r7,1 - - /* Unfortunately, the stack pointer and the MSR are also clobbered, - * so they are saved in the PACA which allows us to restore - * our original state after RTAS returns. - */ - std r1,PACAR1(r13) - std r6,PACASAVEDMSR(r13) - - /* Setup our real return addr */ - LOAD_REG_ADDR(r4,.rtas_return_loc) - clrldi r4,r4,2 /* convert to realmode address */ - mtlr r4 - - li r0,0 - ori r0,r0,MSR_EE|MSR_SE|MSR_BE|MSR_RI - andc r0,r6,r0 - - 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 - andc r6,r0,r9 - sync /* disable interrupts so SRR0/1 */ - mtmsrd r0 /* don't get trashed */ - - LOAD_REG_ADDR(r4, rtas) - ld r5,RTASENTRY(r4) /* get the rtas->entry value */ - ld r4,RTASBASE(r4) /* get the rtas->base value */ - - mtspr SPRN_SRR0,r5 - mtspr SPRN_SRR1,r6 - rfid - b . /* prevent speculative execution */ - -_STATIC(rtas_return_loc) - /* 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 */ - - mfmsr r6 - li r0,MSR_RI - andc r6,r6,r0 - sync - mtmsrd r6 - - ld r1,PACAR1(r4) /* Restore our SP */ - ld r4,PACASAVEDMSR(r4) /* Restore our MSR */ - - mtspr SPRN_SRR0,r3 - mtspr SPRN_SRR1,r4 - rfid - b . /* prevent speculative execution */ - - .align 3 -1: .llong .rtas_restore_regs - -_STATIC(rtas_restore_regs) - /* relocation is on at this point */ - REST_GPR(2, r1) /* Restore the TOC */ - REST_GPR(13, r1) /* Restore paca */ - REST_8GPRS(14, r1) /* Restore the non-volatiles */ - REST_10GPRS(22, r1) /* ditto */ - - GET_PACA(r13) - - ld r4,_CCR(r1) - mtcr r4 - ld r5,_CTR(r1) - mtctr r5 - ld r6,_XER(r1) - mtspr SPRN_XER,r6 - ld r7,_DAR(r1) - mtdar r7 - ld r8,_DSISR(r1) - mtdsisr r8 - - addi r1,r1,RTAS_FRAME_SIZE /* Unstack our frame */ - ld r0,16(r1) /* get return address */ - - mtlr r0 - blr /* return to caller */ - -#endif /* CONFIG_PPC_RTAS */ - -_GLOBAL(enter_prom) - mflr r0 - std r0,16(r1) - stdu r1,-PROM_FRAME_SIZE(r1) /* Save SP and create stack space */ - - /* Because PROM is running in 32b mode, it clobbers the high order half - * of all registers that it saves. We therefore save those registers - * PROM might touch to the stack. (r0, r3-r13 are caller saved) - */ - SAVE_GPR(2, r1) - SAVE_GPR(13, r1) - SAVE_8GPRS(14, r1) - SAVE_10GPRS(22, r1) - mfcr r10 - mfmsr r11 - std r10,_CCR(r1) - std r11,_MSR(r1) - - /* Get the PROM entrypoint */ - mtlr r4 - - /* Switch MSR to 32 bits mode - */ -#ifdef CONFIG_PPC_BOOK3E - rlwinm r11,r11,0,1,31 - mtmsr r11 -#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 -#endif /* CONFIG_PPC_BOOK3E */ - isync - - /* Enter PROM here... */ - blrl - - /* Just make sure that r1 top 32 bits didn't get - * corrupt by OF - */ - rldicl r1,r1,0,32 - - /* Restore the MSR (back to 64 bits) */ - ld r0,_MSR(r1) - MTMSRD(r0) - isync - - /* Restore other registers */ - REST_GPR(2, r1) - REST_GPR(13, r1) - REST_8GPRS(14, r1) - REST_10GPRS(22, r1) - ld r4,_CCR(r1) - mtcr r4 - - addi r1,r1,PROM_FRAME_SIZE - ld r0,16(r1) - mtlr r0 - blr - -#ifdef CONFIG_FUNCTION_TRACER -#ifdef CONFIG_DYNAMIC_FTRACE -_GLOBAL(mcount) -_GLOBAL(_mcount) - blr - -_GLOBAL(ftrace_caller) - /* Taken from output of objdump from lib64/glibc */ - mflr r3 - ld r11, 0(r1) - stdu r1, -112(r1) - std r3, 128(r1) - ld r4, 16(r11) - subi r3, r3, MCOUNT_INSN_SIZE -.globl ftrace_call -ftrace_call: - bl ftrace_stub - nop -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -.globl ftrace_graph_call -ftrace_graph_call: - b ftrace_graph_stub -_GLOBAL(ftrace_graph_stub) -#endif - ld r0, 128(r1) - mtlr r0 - addi r1, r1, 112 -_GLOBAL(ftrace_stub) - blr -#else -_GLOBAL(mcount) - blr - -_GLOBAL(_mcount) - /* Taken from output of objdump from lib64/glibc */ - mflr r3 - ld r11, 0(r1) - stdu r1, -112(r1) - std r3, 128(r1) - ld r4, 16(r11) - - subi r3, r3, MCOUNT_INSN_SIZE - LOAD_REG_ADDR(r5,ftrace_trace_function) - ld r5,0(r5) - ld r5,0(r5) - mtctr r5 - bctrl - nop - - -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - b ftrace_graph_caller -#endif - ld r0, 128(r1) - mtlr r0 - addi r1, r1, 112 -_GLOBAL(ftrace_stub) - blr - -#endif /* CONFIG_DYNAMIC_FTRACE */ - -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -_GLOBAL(ftrace_graph_caller) - /* load r4 with local address */ - ld r4, 128(r1) - subi r4, r4, MCOUNT_INSN_SIZE - - /* get the parent address */ - ld r11, 112(r1) - addi r3, r11, 16 - - bl .prepare_ftrace_return - nop - - ld r0, 128(r1) - mtlr r0 - addi r1, r1, 112 - blr - -_GLOBAL(return_to_handler) - /* need to save return values */ - std r4, -24(r1) - std r3, -16(r1) - std r31, -8(r1) - mr r31, r1 - stdu r1, -112(r1) - - bl .ftrace_return_to_handler - nop - - /* return value has real return address */ - mtlr r3 - - ld r1, 0(r1) - ld r4, -24(r1) - ld r3, -16(r1) - ld r31, -8(r1) - - /* Jump back to real return address */ - blr - -_GLOBAL(mod_return_to_handler) - /* need to save return values */ - std r4, -32(r1) - std r3, -24(r1) - /* save TOC */ - std r2, -16(r1) - std r31, -8(r1) - mr r31, r1 - stdu r1, -112(r1) - - /* - * We are in a module using the module's TOC. - * Switch to our TOC to run inside the core kernel. - */ - ld r2, PACATOC(r13) - - bl .ftrace_return_to_handler - nop - - /* return value has real return address */ - mtlr r3 - - ld r1, 0(r1) - ld r4, -32(r1) - ld r3, -24(r1) - ld r2, -16(r1) - ld r31, -8(r1) - - /* Jump back to real return address */ - blr -#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -#endif /* CONFIG_FUNCTION_TRACER */ |