947 lines
22 KiB
ArmAsm
947 lines
22 KiB
ArmAsm
/*
|
|
* 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>
|
|
|
|
/*
|
|
* 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)
|
|
crclr so
|
|
std r11,_NIP(r1)
|
|
std r12,_MSR(r1)
|
|
std r0,GPR0(r1)
|
|
std r10,GPR1(r1)
|
|
ACCOUNT_CPU_USER_ENTRY(r10, r11)
|
|
std r2,GPR2(r1)
|
|
std r3,GPR3(r1)
|
|
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 r9,GPR13(r1)
|
|
mfcr r9
|
|
mflr r10
|
|
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)
|
|
ld r2,PACATOC(r13)
|
|
addi r9,r1,STACK_FRAME_OVERHEAD
|
|
ld r11,exception_marker@toc(r2)
|
|
std r11,-16(r9) /* "regshere" marker */
|
|
#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 */
|
|
mfmsr r11
|
|
ori r11,r11,MSR_EE
|
|
mtmsrd r11,1
|
|
|
|
#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
|
|
clrrdi r11,r1,THREAD_SHIFT
|
|
ld r10,TI_FLAGS(r11)
|
|
andi. r11,r10,_TIF_SYSCALL_T_OR_A
|
|
bne- syscall_dotrace
|
|
syscall_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
|
|
clrrdi r12,r1,THREAD_SHIFT
|
|
|
|
/* disable interrupts so current_thread_info()->flags can't change,
|
|
and so that we don't get interrupted after loading SRR0/1. */
|
|
ld r8,_MSR(r1)
|
|
andi. r10,r8,MSR_RI
|
|
beq- unrecov_restore
|
|
mfmsr r10
|
|
rldicl r10,r10,48,1
|
|
rotldi r10,r10,16
|
|
mtmsrd r10,1
|
|
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
|
|
syscall_error_cont:
|
|
ld r7,_NIP(r1)
|
|
stdcx. r0,0,r1 /* to clear the reservation */
|
|
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.
|
|
*/
|
|
li r12,MSR_RI
|
|
andc r11,r10,r12
|
|
mtmsrd r11,1 /* clear MSR.RI */
|
|
beq- 1f
|
|
ACCOUNT_CPU_USER_EXIT(r11, r12)
|
|
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
|
|
rfid
|
|
b . /* prevent speculative execution */
|
|
|
|
syscall_error:
|
|
oris r5,r5,0x1000 /* Set SO bit in CR */
|
|
neg r3,r3
|
|
std r5,_CCR(r1)
|
|
b syscall_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
|
|
clrrdi r10,r1,THREAD_SHIFT
|
|
ld r10,TI_FLAGS(r10)
|
|
b syscall_dotrace_cont
|
|
|
|
syscall_enosys:
|
|
li r3,-ENOSYS
|
|
b syscall_exit
|
|
|
|
syscall_exit_work:
|
|
/* 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? */
|
|
andi. r0,r9,(_TIF_SYSCALL_T_OR_A|_TIF_SINGLESTEP)
|
|
beq .ret_from_except_lite
|
|
|
|
/* Re-enable interrupts */
|
|
mfmsr r10
|
|
ori r10,r10,MSR_EE
|
|
mtmsrd r10,1
|
|
|
|
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
|
|
|
|
/*
|
|
* 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 */
|
|
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_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 */
|
|
|
|
addi r6,r4,-THREAD /* Convert THREAD to 'current' */
|
|
std r6,PACACURRENT(r13) /* Set new 'current' */
|
|
|
|
ld r8,KSP(r4) /* new stack pointer */
|
|
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_FTR_SECTION_END_NESTED_IFCLR(CPU_FTR_1T_SEGMENT, 95)
|
|
FTR_SECTION_ELSE
|
|
b 2f
|
|
ALT_FTR_SECTION_END_IFSET(CPU_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_FTR_SECTION_IFSET(CPU_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 CPU_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:
|
|
clrrdi r7,r8,THREAD_SHIFT /* 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)
|
|
|
|
ld r6,_CCR(r1)
|
|
mtcrf 0xFF,r6
|
|
|
|
#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 */
|
|
|
|
/* 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.
|
|
*/
|
|
mfmsr r10 /* Get current interrupt state */
|
|
rldicl r9,r10,48,1 /* clear MSR_EE */
|
|
rotldi r9,r9,16
|
|
mtmsrd r9,1 /* Update machine state */
|
|
|
|
#ifdef CONFIG_PREEMPT
|
|
clrrdi r9,r1,THREAD_SHIFT /* current_thread_info() */
|
|
li r0,_TIF_NEED_RESCHED /* bits to check */
|
|
ld r3,_MSR(r1)
|
|
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 */
|
|
|
|
/* 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
|
|
#endif
|
|
|
|
restore:
|
|
ld r5,SOFTE(r1)
|
|
#ifdef CONFIG_PPC_ISERIES
|
|
BEGIN_FW_FTR_SECTION
|
|
cmpdi 0,r5,0
|
|
beq 4f
|
|
/* Check for pending interrupts (iSeries) */
|
|
ld r3,PACALPPACAPTR(r13)
|
|
ld r3,LPPACAANYINT(r3)
|
|
cmpdi r3,0
|
|
beq+ 4f /* 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 */
|
|
4:
|
|
END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES)
|
|
#endif
|
|
TRACE_AND_RESTORE_IRQ(r5);
|
|
|
|
/* 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)
|
|
|
|
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
|
|
|
|
stdcx. r0,0,r1 /* to clear the reservation */
|
|
|
|
/*
|
|
* 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 */
|
|
mtmsrd r4,1
|
|
|
|
/*
|
|
* r13 is our per cpu area, only restore it if we are returning to
|
|
* userspace
|
|
*/
|
|
andi. r0,r3,MSR_PR
|
|
beq 1f
|
|
ACCOUNT_CPU_USER_EXIT(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 */
|
|
|
|
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 */
|
|
1:
|
|
#ifdef CONFIG_TRACE_IRQFLAGS
|
|
bl .trace_hardirqs_on
|
|
/* Note: we just clobbered r10 which used to contain the previous
|
|
* MSR before the hard-disabling done by the caller of do_work.
|
|
* We don't have that value anymore, but it doesn't matter as
|
|
* we will hard-enable unconditionally, we can just reload the
|
|
* current MSR into r10
|
|
*/
|
|
mfmsr r10
|
|
#endif /* CONFIG_TRACE_IRQFLAGS */
|
|
li r0,1
|
|
stb r0,PACASOFTIRQEN(r13)
|
|
stb r0,PACAHARDIRQEN(r13)
|
|
ori r10,r10,MSR_EE
|
|
mtmsrd r10,1 /* reenable interrupts */
|
|
bl .preempt_schedule
|
|
mfmsr r10
|
|
clrrdi r9,r1,THREAD_SHIFT
|
|
rldicl r10,r10,48,1 /* disable interrupts again */
|
|
rotldi r10,r10,16
|
|
mtmsrd r10,1
|
|
ld r4,TI_FLAGS(r9)
|
|
andi. r0,r4,_TIF_NEED_RESCHED
|
|
bne 1b
|
|
b restore
|
|
|
|
user_work:
|
|
#endif
|
|
/* Enable interrupts */
|
|
ori r10,r10,MSR_EE
|
|
mtmsrd r10,1
|
|
|
|
andi. r0,r4,_TIF_NEED_RESCHED
|
|
beq 1f
|
|
bl .schedule
|
|
b .ret_from_except_lite
|
|
|
|
1: bl .save_nvgprs
|
|
addi r3,r1,STACK_FRAME_OVERHEAD
|
|
bl .do_signal
|
|
b .ret_from_except
|
|
|
|
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)
|
|
mfsrr0 r9
|
|
std r9,_SRR0(r1)
|
|
mfsrr1 r10
|
|
std r10,_SRR1(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
|
|
andc r6,r0,r9
|
|
ori r6,r6,MSR_RI
|
|
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 */
|
|
mfspr r4,SPRN_SPRG3 /* Get PACA */
|
|
clrldi r4,r4,2 /* convert to realmode address */
|
|
|
|
mfmsr r6
|
|
li r0,MSR_RI
|
|
andc r6,r6,r0
|
|
sync
|
|
mtmsrd r6
|
|
|
|
ld r1,PACAR1(r4) /* Restore our SP */
|
|
LOAD_REG_IMMEDIATE(r3,.rtas_restore_regs)
|
|
ld r4,PACASAVEDMSR(r4) /* Restore our MSR */
|
|
|
|
mtspr SPRN_SRR0,r3
|
|
mtspr SPRN_SRR1,r4
|
|
rfid
|
|
b . /* prevent speculative execution */
|
|
|
|
_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 */
|
|
|
|
mfspr r13,SPRN_SPRG3
|
|
|
|
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
|
|
ld r9,_SRR0(r1)
|
|
mtsrr0 r9
|
|
ld r10,_SRR1(r1)
|
|
mtsrr1 r10
|
|
|
|
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_8GPRS(2, r1)
|
|
SAVE_GPR(13, r1)
|
|
SAVE_8GPRS(14, r1)
|
|
SAVE_10GPRS(22, r1)
|
|
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)
|
|
mfsrr0 r9
|
|
std r9,_SRR0(r1)
|
|
mfsrr1 r10
|
|
std r10,_SRR1(r1)
|
|
mfmsr r11
|
|
std r11,_MSR(r1)
|
|
|
|
/* Get the PROM entrypoint */
|
|
ld r0,GPR4(r1)
|
|
mtlr r0
|
|
|
|
/* Switch MSR to 32 bits mode
|
|
*/
|
|
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
|
|
isync
|
|
|
|
/* Restore arguments & enter PROM here... */
|
|
ld r3,GPR3(r1)
|
|
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
|
|
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
|
|
ld r9,_SRR0(r1)
|
|
mtsrr0 r9
|
|
ld r10,_SRR1(r1)
|
|
mtsrr1 r10
|
|
|
|
addi r1,r1,PROM_FRAME_SIZE
|
|
ld r0,16(r1)
|
|
mtlr r0
|
|
blr
|
|
|
|
#ifdef CONFIG_FTRACE
|
|
#ifdef CONFIG_DYNAMIC_FTRACE
|
|
_GLOBAL(mcount)
|
|
_GLOBAL(_mcount)
|
|
/* Taken from output of objdump from lib64/glibc */
|
|
mflr r3
|
|
stdu r1, -112(r1)
|
|
std r3, 128(r1)
|
|
subi r3, r3, MCOUNT_INSN_SIZE
|
|
.globl mcount_call
|
|
mcount_call:
|
|
bl ftrace_stub
|
|
nop
|
|
ld r0, 128(r1)
|
|
mtlr r0
|
|
addi r1, r1, 112
|
|
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
|
|
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
|
|
ld r0, 128(r1)
|
|
mtlr r0
|
|
addi r1, r1, 112
|
|
_GLOBAL(ftrace_stub)
|
|
blr
|
|
|
|
#endif
|
|
#endif
|