linux-stable/arch/powerpc/kernel/exceptions-64e.S
Benjamin Herrenschmidt ff82c319e6 powerpc/book3e: Fix single step when using HW page tables
We patch the TLB miss exception vectors to point to alternate
functions when using HW page table on BookE.

However, we were patching in a new branch in the first instruction
of the exception handler instead of the second one, thus overriding
the nop that is in the first instruction.

This cause problems when single stepping as we rely on that nop for
the single step to stop properly within the exception vector range
rather than on the target of the branch.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-14 14:13:51 +10:00

1042 lines
29 KiB
ArmAsm

/*
* Boot code and exception vectors for Book3E processors
*
* Copyright (C) 2007 Ben. Herrenschmidt (benh@kernel.crashing.org), IBM Corp.
*
* 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/threads.h>
#include <asm/reg.h>
#include <asm/page.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/cputable.h>
#include <asm/setup.h>
#include <asm/thread_info.h>
#include <asm/exception-64e.h>
#include <asm/bug.h>
#include <asm/irqflags.h>
#include <asm/ptrace.h>
#include <asm/ppc-opcode.h>
#include <asm/mmu.h>
/* XXX This will ultimately add space for a special exception save
* structure used to save things like SRR0/SRR1, SPRGs, MAS, etc...
* when taking special interrupts. For now we don't support that,
* special interrupts from within a non-standard level will probably
* blow you up
*/
#define SPECIAL_EXC_FRAME_SIZE INT_FRAME_SIZE
/* Exception prolog code for all exceptions */
#define EXCEPTION_PROLOG(n, type, addition) \
mtspr SPRN_SPRG_##type##_SCRATCH,r13; /* get spare registers */ \
mfspr r13,SPRN_SPRG_PACA; /* get PACA */ \
std r10,PACA_EX##type+EX_R10(r13); \
std r11,PACA_EX##type+EX_R11(r13); \
mfcr r10; /* save CR */ \
addition; /* additional code for that exc. */ \
std r1,PACA_EX##type+EX_R1(r13); /* save old r1 in the PACA */ \
stw r10,PACA_EX##type+EX_CR(r13); /* save old CR in the PACA */ \
mfspr r11,SPRN_##type##_SRR1;/* what are we coming from */ \
type##_SET_KSTACK; /* get special stack if necessary */\
andi. r10,r11,MSR_PR; /* save stack pointer */ \
beq 1f; /* branch around if supervisor */ \
ld r1,PACAKSAVE(r13); /* get kernel stack coming from usr */\
1: cmpdi cr1,r1,0; /* check if SP makes sense */ \
bge- cr1,exc_##n##_bad_stack;/* bad stack (TODO: out of line) */ \
mfspr r10,SPRN_##type##_SRR0; /* read SRR0 before touching stack */
/* Exception type-specific macros */
#define GEN_SET_KSTACK \
subi r1,r1,INT_FRAME_SIZE; /* alloc frame on kernel stack */
#define SPRN_GEN_SRR0 SPRN_SRR0
#define SPRN_GEN_SRR1 SPRN_SRR1
#define CRIT_SET_KSTACK \
ld r1,PACA_CRIT_STACK(r13); \
subi r1,r1,SPECIAL_EXC_FRAME_SIZE;
#define SPRN_CRIT_SRR0 SPRN_CSRR0
#define SPRN_CRIT_SRR1 SPRN_CSRR1
#define DBG_SET_KSTACK \
ld r1,PACA_DBG_STACK(r13); \
subi r1,r1,SPECIAL_EXC_FRAME_SIZE;
#define SPRN_DBG_SRR0 SPRN_DSRR0
#define SPRN_DBG_SRR1 SPRN_DSRR1
#define MC_SET_KSTACK \
ld r1,PACA_MC_STACK(r13); \
subi r1,r1,SPECIAL_EXC_FRAME_SIZE;
#define SPRN_MC_SRR0 SPRN_MCSRR0
#define SPRN_MC_SRR1 SPRN_MCSRR1
#define NORMAL_EXCEPTION_PROLOG(n, addition) \
EXCEPTION_PROLOG(n, GEN, addition##_GEN)
#define CRIT_EXCEPTION_PROLOG(n, addition) \
EXCEPTION_PROLOG(n, CRIT, addition##_CRIT)
#define DBG_EXCEPTION_PROLOG(n, addition) \
EXCEPTION_PROLOG(n, DBG, addition##_DBG)
#define MC_EXCEPTION_PROLOG(n, addition) \
EXCEPTION_PROLOG(n, MC, addition##_MC)
/* Variants of the "addition" argument for the prolog
*/
#define PROLOG_ADDITION_NONE_GEN
#define PROLOG_ADDITION_NONE_CRIT
#define PROLOG_ADDITION_NONE_DBG
#define PROLOG_ADDITION_NONE_MC
#define PROLOG_ADDITION_MASKABLE_GEN \
lbz r11,PACASOFTIRQEN(r13); /* are irqs soft-disabled ? */ \
cmpwi cr0,r11,0; /* yes -> go out of line */ \
beq masked_interrupt_book3e;
#define PROLOG_ADDITION_2REGS_GEN \
std r14,PACA_EXGEN+EX_R14(r13); \
std r15,PACA_EXGEN+EX_R15(r13)
#define PROLOG_ADDITION_1REG_GEN \
std r14,PACA_EXGEN+EX_R14(r13);
#define PROLOG_ADDITION_2REGS_CRIT \
std r14,PACA_EXCRIT+EX_R14(r13); \
std r15,PACA_EXCRIT+EX_R15(r13)
#define PROLOG_ADDITION_2REGS_DBG \
std r14,PACA_EXDBG+EX_R14(r13); \
std r15,PACA_EXDBG+EX_R15(r13)
#define PROLOG_ADDITION_2REGS_MC \
std r14,PACA_EXMC+EX_R14(r13); \
std r15,PACA_EXMC+EX_R15(r13)
/* Core exception code for all exceptions except TLB misses.
* XXX: Needs to make SPRN_SPRG_GEN depend on exception type
*/
#define EXCEPTION_COMMON(n, excf, ints) \
std r0,GPR0(r1); /* save r0 in stackframe */ \
std r2,GPR2(r1); /* save r2 in stackframe */ \
SAVE_4GPRS(3, r1); /* save r3 - r6 in stackframe */ \
SAVE_2GPRS(7, r1); /* save r7, r8 in stackframe */ \
std r9,GPR9(r1); /* save r9 in stackframe */ \
std r10,_NIP(r1); /* save SRR0 to stackframe */ \
std r11,_MSR(r1); /* save SRR1 to stackframe */ \
ACCOUNT_CPU_USER_ENTRY(r10,r11);/* accounting (uses cr0+eq) */ \
ld r3,excf+EX_R10(r13); /* get back r10 */ \
ld r4,excf+EX_R11(r13); /* get back r11 */ \
mfspr r5,SPRN_SPRG_GEN_SCRATCH;/* get back r13 */ \
std r12,GPR12(r1); /* save r12 in stackframe */ \
ld r2,PACATOC(r13); /* get kernel TOC into r2 */ \
mflr r6; /* save LR in stackframe */ \
mfctr r7; /* save CTR in stackframe */ \
mfspr r8,SPRN_XER; /* save XER in stackframe */ \
ld r9,excf+EX_R1(r13); /* load orig r1 back from PACA */ \
lwz r10,excf+EX_CR(r13); /* load orig CR back from PACA */ \
lbz r11,PACASOFTIRQEN(r13); /* get current IRQ softe */ \
ld r12,exception_marker@toc(r2); \
li r0,0; \
std r3,GPR10(r1); /* save r10 to stackframe */ \
std r4,GPR11(r1); /* save r11 to stackframe */ \
std r5,GPR13(r1); /* save it to stackframe */ \
std r6,_LINK(r1); \
std r7,_CTR(r1); \
std r8,_XER(r1); \
li r3,(n)+1; /* indicate partial regs in trap */ \
std r9,0(r1); /* store stack frame back link */ \
std r10,_CCR(r1); /* store orig CR in stackframe */ \
std r9,GPR1(r1); /* store stack frame back link */ \
std r11,SOFTE(r1); /* and save it to stackframe */ \
std r12,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame */ \
std r3,_TRAP(r1); /* set trap number */ \
std r0,RESULT(r1); /* clear regs->result */ \
ints;
/* Variants for the "ints" argument */
#define INTS_KEEP
#define INTS_DISABLE_SOFT \
stb r0,PACASOFTIRQEN(r13); /* mark interrupts soft-disabled */ \
TRACE_DISABLE_INTS;
#define INTS_DISABLE_HARD \
stb r0,PACAHARDIRQEN(r13); /* and hard disabled */
#define INTS_DISABLE_ALL \
INTS_DISABLE_SOFT \
INTS_DISABLE_HARD
/* This is called by exceptions that used INTS_KEEP (that is did not clear
* neither soft nor hard IRQ indicators in the PACA. This will restore MSR:EE
* to it's previous value
*
* XXX In the long run, we may want to open-code it in order to separate the
* load from the wrtee, thus limiting the latency caused by the dependency
* but at this point, I'll favor code clarity until we have a near to final
* implementation
*/
#define INTS_RESTORE_HARD \
ld r11,_MSR(r1); \
wrtee r11;
/* XXX FIXME: Restore r14/r15 when necessary */
#define BAD_STACK_TRAMPOLINE(n) \
exc_##n##_bad_stack: \
li r1,(n); /* get exception number */ \
sth r1,PACA_TRAP_SAVE(r13); /* store trap */ \
b bad_stack_book3e; /* bad stack error */
/* WARNING: If you change the layout of this stub, make sure you chcek
* the debug exception handler which handles single stepping
* into exceptions from userspace, and the MM code in
* arch/powerpc/mm/tlb_nohash.c which patches the branch here
* and would need to be updated if that branch is moved
*/
#define EXCEPTION_STUB(loc, label) \
. = interrupt_base_book3e + loc; \
nop; /* To make debug interrupts happy */ \
b exc_##label##_book3e;
#define ACK_NONE(r)
#define ACK_DEC(r) \
lis r,TSR_DIS@h; \
mtspr SPRN_TSR,r
#define ACK_FIT(r) \
lis r,TSR_FIS@h; \
mtspr SPRN_TSR,r
/* Used by asynchronous interrupt that may happen in the idle loop.
*
* This check if the thread was in the idle loop, and if yes, returns
* to the caller rather than the PC. This is to avoid a race if
* interrupts happen before the wait instruction.
*/
#define CHECK_NAPPING() \
clrrdi r11,r1,THREAD_SHIFT; \
ld r10,TI_LOCAL_FLAGS(r11); \
andi. r9,r10,_TLF_NAPPING; \
beq+ 1f; \
ld r8,_LINK(r1); \
rlwinm r7,r10,0,~_TLF_NAPPING; \
std r8,_NIP(r1); \
std r7,TI_LOCAL_FLAGS(r11); \
1:
#define MASKABLE_EXCEPTION(trapnum, label, hdlr, ack) \
START_EXCEPTION(label); \
NORMAL_EXCEPTION_PROLOG(trapnum, PROLOG_ADDITION_MASKABLE) \
EXCEPTION_COMMON(trapnum, PACA_EXGEN, INTS_DISABLE_ALL) \
ack(r8); \
CHECK_NAPPING(); \
addi r3,r1,STACK_FRAME_OVERHEAD; \
bl hdlr; \
b .ret_from_except_lite;
/* This value is used to mark exception frames on the stack. */
.section ".toc","aw"
exception_marker:
.tc ID_EXC_MARKER[TC],STACK_FRAME_REGS_MARKER
/*
* And here we have the exception vectors !
*/
.text
.balign 0x1000
.globl interrupt_base_book3e
interrupt_base_book3e: /* fake trap */
/* Note: If real debug exceptions are supported by the HW, the vector
* below will have to be patched up to point to an appropriate handler
*/
EXCEPTION_STUB(0x000, machine_check) /* 0x0200 */
EXCEPTION_STUB(0x020, critical_input) /* 0x0580 */
EXCEPTION_STUB(0x040, debug_crit) /* 0x0d00 */
EXCEPTION_STUB(0x060, data_storage) /* 0x0300 */
EXCEPTION_STUB(0x080, instruction_storage) /* 0x0400 */
EXCEPTION_STUB(0x0a0, external_input) /* 0x0500 */
EXCEPTION_STUB(0x0c0, alignment) /* 0x0600 */
EXCEPTION_STUB(0x0e0, program) /* 0x0700 */
EXCEPTION_STUB(0x100, fp_unavailable) /* 0x0800 */
EXCEPTION_STUB(0x120, system_call) /* 0x0c00 */
EXCEPTION_STUB(0x140, ap_unavailable) /* 0x0f20 */
EXCEPTION_STUB(0x160, decrementer) /* 0x0900 */
EXCEPTION_STUB(0x180, fixed_interval) /* 0x0980 */
EXCEPTION_STUB(0x1a0, watchdog) /* 0x09f0 */
EXCEPTION_STUB(0x1c0, data_tlb_miss)
EXCEPTION_STUB(0x1e0, instruction_tlb_miss)
EXCEPTION_STUB(0x280, doorbell)
EXCEPTION_STUB(0x2a0, doorbell_crit)
.globl interrupt_end_book3e
interrupt_end_book3e:
/* Critical Input Interrupt */
START_EXCEPTION(critical_input);
CRIT_EXCEPTION_PROLOG(0x100, PROLOG_ADDITION_NONE)
// EXCEPTION_COMMON(0x100, PACA_EXCRIT, INTS_DISABLE_ALL)
// bl special_reg_save_crit
// CHECK_NAPPING();
// addi r3,r1,STACK_FRAME_OVERHEAD
// bl .critical_exception
// b ret_from_crit_except
b .
/* Machine Check Interrupt */
START_EXCEPTION(machine_check);
CRIT_EXCEPTION_PROLOG(0x200, PROLOG_ADDITION_NONE)
// EXCEPTION_COMMON(0x200, PACA_EXMC, INTS_DISABLE_ALL)
// bl special_reg_save_mc
// addi r3,r1,STACK_FRAME_OVERHEAD
// CHECK_NAPPING();
// bl .machine_check_exception
// b ret_from_mc_except
b .
/* Data Storage Interrupt */
START_EXCEPTION(data_storage)
NORMAL_EXCEPTION_PROLOG(0x300, PROLOG_ADDITION_2REGS)
mfspr r14,SPRN_DEAR
mfspr r15,SPRN_ESR
EXCEPTION_COMMON(0x300, PACA_EXGEN, INTS_KEEP)
b storage_fault_common
/* Instruction Storage Interrupt */
START_EXCEPTION(instruction_storage);
NORMAL_EXCEPTION_PROLOG(0x400, PROLOG_ADDITION_2REGS)
li r15,0
mr r14,r10
EXCEPTION_COMMON(0x400, PACA_EXGEN, INTS_KEEP)
b storage_fault_common
/* External Input Interrupt */
MASKABLE_EXCEPTION(0x500, external_input, .do_IRQ, ACK_NONE)
/* Alignment */
START_EXCEPTION(alignment);
NORMAL_EXCEPTION_PROLOG(0x600, PROLOG_ADDITION_2REGS)
mfspr r14,SPRN_DEAR
mfspr r15,SPRN_ESR
EXCEPTION_COMMON(0x600, PACA_EXGEN, INTS_KEEP)
b alignment_more /* no room, go out of line */
/* Program Interrupt */
START_EXCEPTION(program);
NORMAL_EXCEPTION_PROLOG(0x700, PROLOG_ADDITION_1REG)
mfspr r14,SPRN_ESR
EXCEPTION_COMMON(0x700, PACA_EXGEN, INTS_DISABLE_SOFT)
std r14,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
ld r14,PACA_EXGEN+EX_R14(r13)
bl .save_nvgprs
INTS_RESTORE_HARD
bl .program_check_exception
b .ret_from_except
/* Floating Point Unavailable Interrupt */
START_EXCEPTION(fp_unavailable);
NORMAL_EXCEPTION_PROLOG(0x800, PROLOG_ADDITION_NONE)
/* we can probably do a shorter exception entry for that one... */
EXCEPTION_COMMON(0x800, PACA_EXGEN, INTS_KEEP)
bne 1f /* if from user, just load it up */
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
INTS_RESTORE_HARD
bl .kernel_fp_unavailable_exception
BUG_OPCODE
1: ld r12,_MSR(r1)
bl .load_up_fpu
b fast_exception_return
/* Decrementer Interrupt */
MASKABLE_EXCEPTION(0x900, decrementer, .timer_interrupt, ACK_DEC)
/* Fixed Interval Timer Interrupt */
MASKABLE_EXCEPTION(0x980, fixed_interval, .unknown_exception, ACK_FIT)
/* Watchdog Timer Interrupt */
START_EXCEPTION(watchdog);
CRIT_EXCEPTION_PROLOG(0x9f0, PROLOG_ADDITION_NONE)
// EXCEPTION_COMMON(0x9f0, PACA_EXCRIT, INTS_DISABLE_ALL)
// bl special_reg_save_crit
// CHECK_NAPPING();
// addi r3,r1,STACK_FRAME_OVERHEAD
// bl .unknown_exception
// b ret_from_crit_except
b .
/* System Call Interrupt */
START_EXCEPTION(system_call)
mr r9,r13 /* keep a copy of userland r13 */
mfspr r11,SPRN_SRR0 /* get return address */
mfspr r12,SPRN_SRR1 /* get previous MSR */
mfspr r13,SPRN_SPRG_PACA /* get our PACA */
b system_call_common
/* Auxillary Processor Unavailable Interrupt */
START_EXCEPTION(ap_unavailable);
NORMAL_EXCEPTION_PROLOG(0xf20, PROLOG_ADDITION_NONE)
EXCEPTION_COMMON(0xf20, PACA_EXGEN, INTS_KEEP)
addi r3,r1,STACK_FRAME_OVERHEAD
bl .save_nvgprs
INTS_RESTORE_HARD
bl .unknown_exception
b .ret_from_except
/* Debug exception as a critical interrupt*/
START_EXCEPTION(debug_crit);
CRIT_EXCEPTION_PROLOG(0xd00, PROLOG_ADDITION_2REGS)
/*
* If there is a single step or branch-taken exception in an
* exception entry sequence, it was probably meant to apply to
* the code where the exception occurred (since exception entry
* doesn't turn off DE automatically). We simulate the effect
* of turning off DE on entry to an exception handler by turning
* off DE in the CSRR1 value and clearing the debug status.
*/
mfspr r14,SPRN_DBSR /* check single-step/branch taken */
andis. r15,r14,DBSR_IC@h
beq+ 1f
LOAD_REG_IMMEDIATE(r14,interrupt_base_book3e)
LOAD_REG_IMMEDIATE(r15,interrupt_end_book3e)
cmpld cr0,r10,r14
cmpld cr1,r10,r15
blt+ cr0,1f
bge+ cr1,1f
/* here it looks like we got an inappropriate debug exception. */
lis r14,DBSR_IC@h /* clear the IC event */
rlwinm r11,r11,0,~MSR_DE /* clear DE in the CSRR1 value */
mtspr SPRN_DBSR,r14
mtspr SPRN_CSRR1,r11
lwz r10,PACA_EXCRIT+EX_CR(r13) /* restore registers */
ld r1,PACA_EXCRIT+EX_R1(r13)
ld r14,PACA_EXCRIT+EX_R14(r13)
ld r15,PACA_EXCRIT+EX_R15(r13)
mtcr r10
ld r10,PACA_EXCRIT+EX_R10(r13) /* restore registers */
ld r11,PACA_EXCRIT+EX_R11(r13)
mfspr r13,SPRN_SPRG_CRIT_SCRATCH
rfci
/* Normal debug exception */
/* XXX We only handle coming from userspace for now since we can't
* quite save properly an interrupted kernel state yet
*/
1: andi. r14,r11,MSR_PR; /* check for userspace again */
beq kernel_dbg_exc; /* if from kernel mode */
/* Now we mash up things to make it look like we are coming on a
* normal exception
*/
mfspr r15,SPRN_SPRG_CRIT_SCRATCH
mtspr SPRN_SPRG_GEN_SCRATCH,r15
mfspr r14,SPRN_DBSR
EXCEPTION_COMMON(0xd00, PACA_EXCRIT, INTS_DISABLE_ALL)
std r14,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
mr r4,r14
ld r14,PACA_EXCRIT+EX_R14(r13)
ld r15,PACA_EXCRIT+EX_R15(r13)
bl .save_nvgprs
bl .DebugException
b .ret_from_except
kernel_dbg_exc:
b . /* NYI */
/* Doorbell interrupt */
MASKABLE_EXCEPTION(0x2070, doorbell, .doorbell_exception, ACK_NONE)
/* Doorbell critical Interrupt */
START_EXCEPTION(doorbell_crit);
CRIT_EXCEPTION_PROLOG(0x2080, PROLOG_ADDITION_NONE)
// EXCEPTION_COMMON(0x2080, PACA_EXCRIT, INTS_DISABLE_ALL)
// bl special_reg_save_crit
// CHECK_NAPPING();
// addi r3,r1,STACK_FRAME_OVERHEAD
// bl .doorbell_critical_exception
// b ret_from_crit_except
b .
/*
* An interrupt came in while soft-disabled; clear EE in SRR1,
* clear paca->hard_enabled and return.
*/
masked_interrupt_book3e:
mtcr r10
stb r11,PACAHARDIRQEN(r13)
mfspr r10,SPRN_SRR1
rldicl r11,r10,48,1 /* clear MSR_EE */
rotldi r10,r11,16
mtspr SPRN_SRR1,r10
ld r10,PACA_EXGEN+EX_R10(r13); /* restore registers */
ld r11,PACA_EXGEN+EX_R11(r13);
mfspr r13,SPRN_SPRG_GEN_SCRATCH;
rfi
b .
/*
* This is called from 0x300 and 0x400 handlers after the prologs with
* r14 and r15 containing the fault address and error code, with the
* original values stashed away in the PACA
*/
storage_fault_common:
std r14,_DAR(r1)
std r15,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
mr r4,r14
mr r5,r15
ld r14,PACA_EXGEN+EX_R14(r13)
ld r15,PACA_EXGEN+EX_R15(r13)
INTS_RESTORE_HARD
bl .do_page_fault
cmpdi r3,0
bne- 1f
b .ret_from_except_lite
1: bl .save_nvgprs
mr r5,r3
addi r3,r1,STACK_FRAME_OVERHEAD
ld r4,_DAR(r1)
bl .bad_page_fault
b .ret_from_except
/*
* Alignment exception doesn't fit entirely in the 0x100 bytes so it
* continues here.
*/
alignment_more:
std r14,_DAR(r1)
std r15,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
ld r14,PACA_EXGEN+EX_R14(r13)
ld r15,PACA_EXGEN+EX_R15(r13)
bl .save_nvgprs
INTS_RESTORE_HARD
bl .alignment_exception
b .ret_from_except
/*
* We branch here from entry_64.S for the last stage of the exception
* return code path. MSR:EE is expected to be off at that point
*/
_GLOBAL(exception_return_book3e)
b 1f
/* This is the return from load_up_fpu fast path which could do with
* less GPR restores in fact, but for now we have a single return path
*/
.globl fast_exception_return
fast_exception_return:
wrteei 0
1: mr r0,r13
ld r10,_MSR(r1)
REST_4GPRS(2, r1)
andi. r6,r10,MSR_PR
REST_2GPRS(6, r1)
beq 1f
ACCOUNT_CPU_USER_EXIT(r10, r11)
ld r0,GPR13(r1)
1: stdcx. r0,0,r1 /* to clear the reservation */
ld r8,_CCR(r1)
ld r9,_LINK(r1)
ld r10,_CTR(r1)
ld r11,_XER(r1)
mtcr r8
mtlr r9
mtctr r10
mtxer r11
REST_2GPRS(8, r1)
ld r10,GPR10(r1)
ld r11,GPR11(r1)
ld r12,GPR12(r1)
mtspr SPRN_SPRG_GEN_SCRATCH,r0
std r10,PACA_EXGEN+EX_R10(r13);
std r11,PACA_EXGEN+EX_R11(r13);
ld r10,_NIP(r1)
ld r11,_MSR(r1)
ld r0,GPR0(r1)
ld r1,GPR1(r1)
mtspr SPRN_SRR0,r10
mtspr SPRN_SRR1,r11
ld r10,PACA_EXGEN+EX_R10(r13)
ld r11,PACA_EXGEN+EX_R11(r13)
mfspr r13,SPRN_SPRG_GEN_SCRATCH
rfi
/*
* Trampolines used when spotting a bad kernel stack pointer in
* the exception entry code.
*
* TODO: move some bits like SRR0 read to trampoline, pass PACA
* index around, etc... to handle crit & mcheck
*/
BAD_STACK_TRAMPOLINE(0x000)
BAD_STACK_TRAMPOLINE(0x100)
BAD_STACK_TRAMPOLINE(0x200)
BAD_STACK_TRAMPOLINE(0x300)
BAD_STACK_TRAMPOLINE(0x400)
BAD_STACK_TRAMPOLINE(0x500)
BAD_STACK_TRAMPOLINE(0x600)
BAD_STACK_TRAMPOLINE(0x700)
BAD_STACK_TRAMPOLINE(0x800)
BAD_STACK_TRAMPOLINE(0x900)
BAD_STACK_TRAMPOLINE(0x980)
BAD_STACK_TRAMPOLINE(0x9f0)
BAD_STACK_TRAMPOLINE(0xa00)
BAD_STACK_TRAMPOLINE(0xb00)
BAD_STACK_TRAMPOLINE(0xc00)
BAD_STACK_TRAMPOLINE(0xd00)
BAD_STACK_TRAMPOLINE(0xe00)
BAD_STACK_TRAMPOLINE(0xf00)
BAD_STACK_TRAMPOLINE(0xf20)
BAD_STACK_TRAMPOLINE(0x2070)
BAD_STACK_TRAMPOLINE(0x2080)
.globl bad_stack_book3e
bad_stack_book3e:
/* XXX: Needs to make SPRN_SPRG_GEN depend on exception type */
mfspr r10,SPRN_SRR0; /* read SRR0 before touching stack */
ld r1,PACAEMERGSP(r13)
subi r1,r1,64+INT_FRAME_SIZE
std r10,_NIP(r1)
std r11,_MSR(r1)
ld r10,PACA_EXGEN+EX_R1(r13) /* FIXME for crit & mcheck */
lwz r11,PACA_EXGEN+EX_CR(r13) /* FIXME for crit & mcheck */
std r10,GPR1(r1)
std r11,_CCR(r1)
mfspr r10,SPRN_DEAR
mfspr r11,SPRN_ESR
std r10,_DAR(r1)
std r11,_DSISR(r1)
std r0,GPR0(r1); /* save r0 in stackframe */ \
std r2,GPR2(r1); /* save r2 in stackframe */ \
SAVE_4GPRS(3, r1); /* save r3 - r6 in stackframe */ \
SAVE_2GPRS(7, r1); /* save r7, r8 in stackframe */ \
std r9,GPR9(r1); /* save r9 in stackframe */ \
ld r3,PACA_EXGEN+EX_R10(r13);/* get back r10 */ \
ld r4,PACA_EXGEN+EX_R11(r13);/* get back r11 */ \
mfspr r5,SPRN_SPRG_GEN_SCRATCH;/* get back r13 XXX can be wrong */ \
std r3,GPR10(r1); /* save r10 to stackframe */ \
std r4,GPR11(r1); /* save r11 to stackframe */ \
std r12,GPR12(r1); /* save r12 in stackframe */ \
std r5,GPR13(r1); /* save it to stackframe */ \
mflr r10
mfctr r11
mfxer r12
std r10,_LINK(r1)
std r11,_CTR(r1)
std r12,_XER(r1)
SAVE_10GPRS(14,r1)
SAVE_8GPRS(24,r1)
lhz r12,PACA_TRAP_SAVE(r13)
std r12,_TRAP(r1)
addi r11,r1,INT_FRAME_SIZE
std r11,0(r1)
li r12,0
std r12,0(r11)
ld r2,PACATOC(r13)
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl .kernel_bad_stack
b 1b
/*
* Setup the initial TLB for a core. This current implementation
* assume that whatever we are running off will not conflict with
* the new mapping at PAGE_OFFSET.
*/
_GLOBAL(initial_tlb_book3e)
/* Look for the first TLB with IPROT set */
mfspr r4,SPRN_TLB0CFG
andi. r3,r4,TLBnCFG_IPROT
lis r3,MAS0_TLBSEL(0)@h
bne found_iprot
mfspr r4,SPRN_TLB1CFG
andi. r3,r4,TLBnCFG_IPROT
lis r3,MAS0_TLBSEL(1)@h
bne found_iprot
mfspr r4,SPRN_TLB2CFG
andi. r3,r4,TLBnCFG_IPROT
lis r3,MAS0_TLBSEL(2)@h
bne found_iprot
lis r3,MAS0_TLBSEL(3)@h
mfspr r4,SPRN_TLB3CFG
/* fall through */
found_iprot:
andi. r5,r4,TLBnCFG_HES
bne have_hes
mflr r8 /* save LR */
/* 1. Find the index of the entry we're executing in
*
* r3 = MAS0_TLBSEL (for the iprot array)
* r4 = SPRN_TLBnCFG
*/
bl invstr /* Find our address */
invstr: mflr r6 /* Make it accessible */
mfmsr r7
rlwinm r5,r7,27,31,31 /* extract MSR[IS] */
mfspr r7,SPRN_PID
slwi r7,r7,16
or r7,r7,r5
mtspr SPRN_MAS6,r7
tlbsx 0,r6 /* search MSR[IS], SPID=PID */
mfspr r3,SPRN_MAS0
rlwinm r5,r3,16,20,31 /* Extract MAS0(Entry) */
mfspr r7,SPRN_MAS1 /* Insure IPROT set */
oris r7,r7,MAS1_IPROT@h
mtspr SPRN_MAS1,r7
tlbwe
/* 2. Invalidate all entries except the entry we're executing in
*
* r3 = MAS0 w/TLBSEL & ESEL for the entry we are running in
* r4 = SPRN_TLBnCFG
* r5 = ESEL of entry we are running in
*/
andi. r4,r4,TLBnCFG_N_ENTRY /* Extract # entries */
li r6,0 /* Set Entry counter to 0 */
1: mr r7,r3 /* Set MAS0(TLBSEL) */
rlwimi r7,r6,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r6) */
mtspr SPRN_MAS0,r7
tlbre
mfspr r7,SPRN_MAS1
rlwinm r7,r7,0,2,31 /* Clear MAS1 Valid and IPROT */
cmpw r5,r6
beq skpinv /* Dont update the current execution TLB */
mtspr SPRN_MAS1,r7
tlbwe
isync
skpinv: addi r6,r6,1 /* Increment */
cmpw r6,r4 /* Are we done? */
bne 1b /* If not, repeat */
/* Invalidate all TLBs */
PPC_TLBILX_ALL(0,0)
sync
isync
/* 3. Setup a temp mapping and jump to it
*
* r3 = MAS0 w/TLBSEL & ESEL for the entry we are running in
* r5 = ESEL of entry we are running in
*/
andi. r7,r5,0x1 /* Find an entry not used and is non-zero */
addi r7,r7,0x1
mr r4,r3 /* Set MAS0(TLBSEL) = 1 */
mtspr SPRN_MAS0,r4
tlbre
rlwimi r4,r7,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r7) */
mtspr SPRN_MAS0,r4
mfspr r7,SPRN_MAS1
xori r6,r7,MAS1_TS /* Setup TMP mapping in the other Address space */
mtspr SPRN_MAS1,r6
tlbwe
mfmsr r6
xori r6,r6,MSR_IS
mtspr SPRN_SRR1,r6
bl 1f /* Find our address */
1: mflr r6
addi r6,r6,(2f - 1b)
mtspr SPRN_SRR0,r6
rfi
2:
/* 4. Clear out PIDs & Search info
*
* r3 = MAS0 w/TLBSEL & ESEL for the entry we started in
* r4 = MAS0 w/TLBSEL & ESEL for the temp mapping
* r5 = MAS3
*/
li r6,0
mtspr SPRN_MAS6,r6
mtspr SPRN_PID,r6
/* 5. Invalidate mapping we started in
*
* r3 = MAS0 w/TLBSEL & ESEL for the entry we started in
* r4 = MAS0 w/TLBSEL & ESEL for the temp mapping
* r5 = MAS3
*/
mtspr SPRN_MAS0,r3
tlbre
mfspr r6,SPRN_MAS1
rlwinm r6,r6,0,2,0 /* clear IPROT */
mtspr SPRN_MAS1,r6
tlbwe
/* Invalidate TLB1 */
PPC_TLBILX_ALL(0,0)
sync
isync
/* The mapping only needs to be cache-coherent on SMP */
#ifdef CONFIG_SMP
#define M_IF_SMP MAS2_M
#else
#define M_IF_SMP 0
#endif
/* 6. Setup KERNELBASE mapping in TLB[0]
*
* r3 = MAS0 w/TLBSEL & ESEL for the entry we started in
* r4 = MAS0 w/TLBSEL & ESEL for the temp mapping
* r5 = MAS3
*/
rlwinm r3,r3,0,16,3 /* clear ESEL */
mtspr SPRN_MAS0,r3
lis r6,(MAS1_VALID|MAS1_IPROT)@h
ori r6,r6,(MAS1_TSIZE(BOOK3E_PAGESZ_1GB))@l
mtspr SPRN_MAS1,r6
LOAD_REG_IMMEDIATE(r6, PAGE_OFFSET | M_IF_SMP)
mtspr SPRN_MAS2,r6
rlwinm r5,r5,0,0,25
ori r5,r5,MAS3_SR | MAS3_SW | MAS3_SX
mtspr SPRN_MAS3,r5
li r5,-1
rlwinm r5,r5,0,0,25
tlbwe
/* 7. Jump to KERNELBASE mapping
*
* r4 = MAS0 w/TLBSEL & ESEL for the temp mapping
*/
/* Now we branch the new virtual address mapped by this entry */
LOAD_REG_IMMEDIATE(r6,2f)
lis r7,MSR_KERNEL@h
ori r7,r7,MSR_KERNEL@l
mtspr SPRN_SRR0,r6
mtspr SPRN_SRR1,r7
rfi /* start execution out of TLB1[0] entry */
2:
/* 8. Clear out the temp mapping
*
* r4 = MAS0 w/TLBSEL & ESEL for the entry we are running in
*/
mtspr SPRN_MAS0,r4
tlbre
mfspr r5,SPRN_MAS1
rlwinm r5,r5,0,2,0 /* clear IPROT */
mtspr SPRN_MAS1,r5
tlbwe
/* Invalidate TLB1 */
PPC_TLBILX_ALL(0,0)
sync
isync
/* We translate LR and return */
tovirt(r8,r8)
mtlr r8
blr
have_hes:
/* Setup MAS 0,1,2,3 and 7 for tlbwe of a 1G entry that maps the
* kernel linear mapping. We also set MAS8 once for all here though
* that will have to be made dependent on whether we are running under
* a hypervisor I suppose.
*/
ori r3,r3,MAS0_HES | MAS0_WQ_ALLWAYS
mtspr SPRN_MAS0,r3
lis r3,(MAS1_VALID | MAS1_IPROT)@h
ori r3,r3,BOOK3E_PAGESZ_1GB << MAS1_TSIZE_SHIFT
mtspr SPRN_MAS1,r3
LOAD_REG_IMMEDIATE(r3, PAGE_OFFSET | MAS2_M)
mtspr SPRN_MAS2,r3
li r3,MAS3_SR | MAS3_SW | MAS3_SX
mtspr SPRN_MAS7_MAS3,r3
li r3,0
mtspr SPRN_MAS8,r3
/* Write the TLB entry */
tlbwe
/* Now we branch the new virtual address mapped by this entry */
LOAD_REG_IMMEDIATE(r3,1f)
mtctr r3
bctr
1: /* We are now running at PAGE_OFFSET, clean the TLB of everything
* else (XXX we should scan for bolted crap from the firmware too)
*/
PPC_TLBILX(0,0,0)
sync
isync
/* We translate LR and return */
mflr r3
tovirt(r3,r3)
mtlr r3
blr
/*
* Main entry (boot CPU, thread 0)
*
* We enter here from head_64.S, possibly after the prom_init trampoline
* with r3 and r4 already saved to r31 and 30 respectively and in 64 bits
* mode. Anything else is as it was left by the bootloader
*
* Initial requirements of this port:
*
* - Kernel loaded at 0 physical
* - A good lump of memory mapped 0:0 by UTLB entry 0
* - MSR:IS & MSR:DS set to 0
*
* Note that some of the above requirements will be relaxed in the future
* as the kernel becomes smarter at dealing with different initial conditions
* but for now you have to be careful
*/
_GLOBAL(start_initialization_book3e)
mflr r28
/* First, we need to setup some initial TLBs to map the kernel
* text, data and bss at PAGE_OFFSET. We don't have a real mode
* and always use AS 0, so we just set it up to match our link
* address and never use 0 based addresses.
*/
bl .initial_tlb_book3e
/* Init global core bits */
bl .init_core_book3e
/* Init per-thread bits */
bl .init_thread_book3e
/* Return to common init code */
tovirt(r28,r28)
mtlr r28
blr
/*
* Secondary core/processor entry
*
* This is entered for thread 0 of a secondary core, all other threads
* are expected to be stopped. It's similar to start_initialization_book3e
* except that it's generally entered from the holding loop in head_64.S
* after CPUs have been gathered by Open Firmware.
*
* We assume we are in 32 bits mode running with whatever TLB entry was
* set for us by the firmware or POR engine.
*/
_GLOBAL(book3e_secondary_core_init_tlb_set)
li r4,1
b .generic_secondary_smp_init
_GLOBAL(book3e_secondary_core_init)
mflr r28
/* Do we need to setup initial TLB entry ? */
cmplwi r4,0
bne 2f
/* Setup TLB for this core */
bl .initial_tlb_book3e
/* We can return from the above running at a different
* address, so recalculate r2 (TOC)
*/
bl .relative_toc
/* Init global core bits */
2: bl .init_core_book3e
/* Init per-thread bits */
3: bl .init_thread_book3e
/* Return to common init code at proper virtual address.
*
* Due to various previous assumptions, we know we entered this
* function at either the final PAGE_OFFSET mapping or using a
* 1:1 mapping at 0, so we don't bother doing a complicated check
* here, we just ensure the return address has the right top bits.
*
* Note that if we ever want to be smarter about where we can be
* started from, we have to be careful that by the time we reach
* the code below we may already be running at a different location
* than the one we were called from since initial_tlb_book3e can
* have moved us already.
*/
cmpdi cr0,r28,0
blt 1f
lis r3,PAGE_OFFSET@highest
sldi r3,r3,32
or r28,r28,r3
1: mtlr r28
blr
_GLOBAL(book3e_secondary_thread_init)
mflr r28
b 3b
_STATIC(init_core_book3e)
/* Establish the interrupt vector base */
LOAD_REG_IMMEDIATE(r3, interrupt_base_book3e)
mtspr SPRN_IVPR,r3
sync
blr
_STATIC(init_thread_book3e)
lis r3,(SPRN_EPCR_ICM | SPRN_EPCR_GICM)@h
mtspr SPRN_EPCR,r3
/* Make sure interrupts are off */
wrteei 0
/* disable all timers and clear out status */
li r3,0
mtspr SPRN_TCR,r3
mfspr r3,SPRN_TSR
mtspr SPRN_TSR,r3
blr
_GLOBAL(__setup_base_ivors)
SET_IVOR(0, 0x020) /* Critical Input */
SET_IVOR(1, 0x000) /* Machine Check */
SET_IVOR(2, 0x060) /* Data Storage */
SET_IVOR(3, 0x080) /* Instruction Storage */
SET_IVOR(4, 0x0a0) /* External Input */
SET_IVOR(5, 0x0c0) /* Alignment */
SET_IVOR(6, 0x0e0) /* Program */
SET_IVOR(7, 0x100) /* FP Unavailable */
SET_IVOR(8, 0x120) /* System Call */
SET_IVOR(9, 0x140) /* Auxiliary Processor Unavailable */
SET_IVOR(10, 0x160) /* Decrementer */
SET_IVOR(11, 0x180) /* Fixed Interval Timer */
SET_IVOR(12, 0x1a0) /* Watchdog Timer */
SET_IVOR(13, 0x1c0) /* Data TLB Error */
SET_IVOR(14, 0x1e0) /* Instruction TLB Error */
SET_IVOR(15, 0x040) /* Debug */
sync
blr