android_kernel_xiaomi_sm8350/arch/ppc64/kernel/head.S

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/*
* arch/ppc64/kernel/head.S
*
* 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.
*
* Adapted for 64bit PowerPC by Dave Engebretsen, Peter Bergner, and
* Mike Corrigan {engebret|bergner|mikejc}@us.ibm.com
*
* This file contains the low-level support and setup for the
* PowerPC-64 platform, including trap and interrupt dispatch.
*
* 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/config.h>
#include <linux/threads.h>
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/mmu.h>
#include <asm/systemcfg.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/bug.h>
#include <asm/cputable.h>
#include <asm/setup.h>
#include <asm/hvcall.h>
#include <asm/iSeries/LparMap.h>
#ifdef CONFIG_PPC_ISERIES
#define DO_SOFT_DISABLE
#endif
/*
* We layout physical memory as follows:
* 0x0000 - 0x00ff : Secondary processor spin code
* 0x0100 - 0x2fff : pSeries Interrupt prologs
* 0x3000 - 0x5fff : interrupt support, iSeries and common interrupt prologs
* 0x6000 - 0x6fff : Initial (CPU0) segment table
* 0x7000 - 0x7fff : FWNMI data area
* 0x8000 - : Early init and support code
*/
/*
* SPRG Usage
*
* Register Definition
*
* SPRG0 reserved for hypervisor
* SPRG1 temp - used to save gpr
* SPRG2 temp - used to save gpr
* SPRG3 virt addr of paca
*/
/*
* Entering into this code we make the following assumptions:
* For pSeries:
* 1. The MMU is off & open firmware is running in real mode.
* 2. The kernel is entered at __start
*
* For iSeries:
* 1. The MMU is on (as it always is for iSeries)
* 2. The kernel is entered at system_reset_iSeries
*/
.text
.globl _stext
_stext:
#ifdef CONFIG_PPC_MULTIPLATFORM
_GLOBAL(__start)
/* NOP this out unconditionally */
BEGIN_FTR_SECTION
b .__start_initialization_multiplatform
END_FTR_SECTION(0, 1)
#endif /* CONFIG_PPC_MULTIPLATFORM */
/* Catch branch to 0 in real mode */
trap
#ifdef CONFIG_PPC_ISERIES
/*
* At offset 0x20, there is a pointer to iSeries LPAR data.
* This is required by the hypervisor
*/
. = 0x20
.llong hvReleaseData-KERNELBASE
/*
* At offset 0x28 and 0x30 are offsets to the mschunks_map
* array (used by the iSeries LPAR debugger to do translation
* between physical addresses and absolute addresses) and
* to the pidhash table (also used by the debugger)
*/
.llong mschunks_map-KERNELBASE
.llong 0 /* pidhash-KERNELBASE SFRXXX */
/* Offset 0x38 - Pointer to start of embedded System.map */
.globl embedded_sysmap_start
embedded_sysmap_start:
.llong 0
/* Offset 0x40 - Pointer to end of embedded System.map */
.globl embedded_sysmap_end
embedded_sysmap_end:
.llong 0
#endif /* CONFIG_PPC_ISERIES */
/* Secondary processors spin on this value until it goes to 1. */
.globl __secondary_hold_spinloop
__secondary_hold_spinloop:
.llong 0x0
/* Secondary processors write this value with their cpu # */
/* after they enter the spin loop immediately below. */
.globl __secondary_hold_acknowledge
__secondary_hold_acknowledge:
.llong 0x0
. = 0x60
/*
* The following code is used on pSeries to hold secondary processors
* in a spin loop after they have been freed from OpenFirmware, but
* before the bulk of the kernel has been relocated. This code
* is relocated to physical address 0x60 before prom_init is run.
* All of it must fit below the first exception vector at 0x100.
*/
_GLOBAL(__secondary_hold)
mfmsr r24
ori r24,r24,MSR_RI
mtmsrd r24 /* RI on */
/* Grab our linux cpu number */
mr r24,r3
/* Tell the master cpu we're here */
/* Relocation is off & we are located at an address less */
/* than 0x100, so only need to grab low order offset. */
std r24,__secondary_hold_acknowledge@l(0)
sync
/* All secondary cpus wait here until told to start. */
100: ld r4,__secondary_hold_spinloop@l(0)
cmpdi 0,r4,1
bne 100b
#ifdef CONFIG_HMT
b .hmt_init
#else
#ifdef CONFIG_SMP
mr r3,r24
b .pSeries_secondary_smp_init
#else
BUG_OPCODE
#endif
#endif
/* This value is used to mark exception frames on the stack. */
.section ".toc","aw"
exception_marker:
.tc ID_72656773_68657265[TC],0x7265677368657265
.text
/*
* The following macros define the code that appears as
* the prologue to each of the exception handlers. They
* are split into two parts to allow a single kernel binary
* to be used for pSeries and iSeries.
* LOL. One day... - paulus
*/
/*
* We make as much of the exception code common between native
* exception handlers (including pSeries LPAR) and iSeries LPAR
* implementations as possible.
*/
/*
* This is the start of the interrupt handlers for pSeries
* This code runs with relocation off.
*/
#define EX_R9 0
#define EX_R10 8
#define EX_R11 16
#define EX_R12 24
#define EX_R13 32
#define EX_SRR0 40
#define EX_R3 40 /* SLB miss saves R3, but not SRR0 */
#define EX_DAR 48
#define EX_LR 48 /* SLB miss saves LR, but not DAR */
#define EX_DSISR 56
#define EX_CCR 60
#define EXCEPTION_PROLOG_PSERIES(area, label) \
mfspr r13,SPRG3; /* get paca address into r13 */ \
std r9,area+EX_R9(r13); /* save r9 - r12 */ \
std r10,area+EX_R10(r13); \
std r11,area+EX_R11(r13); \
std r12,area+EX_R12(r13); \
mfspr r9,SPRG1; \
std r9,area+EX_R13(r13); \
mfcr r9; \
clrrdi r12,r13,32; /* get high part of &label */ \
mfmsr r10; \
mfspr r11,SRR0; /* save SRR0 */ \
ori r12,r12,(label)@l; /* virt addr of handler */ \
ori r10,r10,MSR_IR|MSR_DR|MSR_RI; \
mtspr SRR0,r12; \
mfspr r12,SRR1; /* and SRR1 */ \
mtspr SRR1,r10; \
rfid; \
b . /* prevent speculative execution */
/*
* This is the start of the interrupt handlers for iSeries
* This code runs with relocation on.
*/
#define EXCEPTION_PROLOG_ISERIES_1(area) \
mfspr r13,SPRG3; /* get paca address into r13 */ \
std r9,area+EX_R9(r13); /* save r9 - r12 */ \
std r10,area+EX_R10(r13); \
std r11,area+EX_R11(r13); \
std r12,area+EX_R12(r13); \
mfspr r9,SPRG1; \
std r9,area+EX_R13(r13); \
mfcr r9
#define EXCEPTION_PROLOG_ISERIES_2 \
mfmsr r10; \
ld r11,PACALPPACA+LPPACASRR0(r13); \
ld r12,PACALPPACA+LPPACASRR1(r13); \
ori r10,r10,MSR_RI; \
mtmsrd r10,1
/*
* The common exception prolog is used for all except a few exceptions
* such as a segment miss on a kernel address. We have to be prepared
* to take another exception from the point where we first touch the
* kernel stack onwards.
*
* On entry r13 points to the paca, r9-r13 are saved in the paca,
* r9 contains the saved CR, r11 and r12 contain the saved SRR0 and
* SRR1, and relocation is on.
*/
#define EXCEPTION_PROLOG_COMMON(n, area) \
andi. r10,r12,MSR_PR; /* See if coming from user */ \
mr r10,r1; /* Save r1 */ \
subi r1,r1,INT_FRAME_SIZE; /* alloc frame on kernel stack */ \
beq- 1f; \
ld r1,PACAKSAVE(r13); /* kernel stack to use */ \
1: cmpdi cr1,r1,0; /* check if r1 is in userspace */ \
bge- cr1,bad_stack; /* abort if it is */ \
std r9,_CCR(r1); /* save CR in stackframe */ \
std r11,_NIP(r1); /* save SRR0 in stackframe */ \
std r12,_MSR(r1); /* save SRR1 in stackframe */ \
std r10,0(r1); /* make stack chain pointer */ \
std r0,GPR0(r1); /* save r0 in stackframe */ \
std r10,GPR1(r1); /* save r1 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 */ \
ld r9,area+EX_R9(r13); /* move r9, r10 to stackframe */ \
ld r10,area+EX_R10(r13); \
std r9,GPR9(r1); \
std r10,GPR10(r1); \
ld r9,area+EX_R11(r13); /* move r11 - r13 to stackframe */ \
ld r10,area+EX_R12(r13); \
ld r11,area+EX_R13(r13); \
std r9,GPR11(r1); \
std r10,GPR12(r1); \
std r11,GPR13(r1); \
ld r2,PACATOC(r13); /* get kernel TOC into r2 */ \
mflr r9; /* save LR in stackframe */ \
std r9,_LINK(r1); \
mfctr r10; /* save CTR in stackframe */ \
std r10,_CTR(r1); \
mfspr r11,XER; /* save XER in stackframe */ \
std r11,_XER(r1); \
li r9,(n)+1; \
std r9,_TRAP(r1); /* set trap number */ \
li r10,0; \
ld r11,exception_marker@toc(r2); \
std r10,RESULT(r1); /* clear regs->result */ \
std r11,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame */
/*
* Exception vectors.
*/
#define STD_EXCEPTION_PSERIES(n, label) \
. = n; \
.globl label##_pSeries; \
label##_pSeries: \
HMT_MEDIUM; \
mtspr SPRG1,r13; /* save r13 */ \
RUNLATCH_ON(r13); \
EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common)
#define STD_EXCEPTION_ISERIES(n, label, area) \
.globl label##_iSeries; \
label##_iSeries: \
HMT_MEDIUM; \
mtspr SPRG1,r13; /* save r13 */ \
RUNLATCH_ON(r13); \
EXCEPTION_PROLOG_ISERIES_1(area); \
EXCEPTION_PROLOG_ISERIES_2; \
b label##_common
#define MASKABLE_EXCEPTION_ISERIES(n, label) \
.globl label##_iSeries; \
label##_iSeries: \
HMT_MEDIUM; \
mtspr SPRG1,r13; /* save r13 */ \
RUNLATCH_ON(r13); \
EXCEPTION_PROLOG_ISERIES_1(PACA_EXGEN); \
lbz r10,PACAPROCENABLED(r13); \
cmpwi 0,r10,0; \
beq- label##_iSeries_masked; \
EXCEPTION_PROLOG_ISERIES_2; \
b label##_common; \
#ifdef DO_SOFT_DISABLE
#define DISABLE_INTS \
lbz r10,PACAPROCENABLED(r13); \
li r11,0; \
std r10,SOFTE(r1); \
mfmsr r10; \
stb r11,PACAPROCENABLED(r13); \
ori r10,r10,MSR_EE; \
mtmsrd r10,1
#define ENABLE_INTS \
lbz r10,PACAPROCENABLED(r13); \
mfmsr r11; \
std r10,SOFTE(r1); \
ori r11,r11,MSR_EE; \
mtmsrd r11,1
#else /* hard enable/disable interrupts */
#define DISABLE_INTS
#define ENABLE_INTS \
ld r12,_MSR(r1); \
mfmsr r11; \
rlwimi r11,r12,0,MSR_EE; \
mtmsrd r11,1
#endif
#define STD_EXCEPTION_COMMON(trap, label, hdlr) \
.align 7; \
.globl label##_common; \
label##_common: \
EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN); \
DISABLE_INTS; \
bl .save_nvgprs; \
addi r3,r1,STACK_FRAME_OVERHEAD; \
bl hdlr; \
b .ret_from_except
#define STD_EXCEPTION_COMMON_LITE(trap, label, hdlr) \
.align 7; \
.globl label##_common; \
label##_common: \
EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN); \
DISABLE_INTS; \
addi r3,r1,STACK_FRAME_OVERHEAD; \
bl hdlr; \
b .ret_from_except_lite
/*
* Start of pSeries system interrupt routines
*/
. = 0x100
.globl __start_interrupts
__start_interrupts:
STD_EXCEPTION_PSERIES(0x100, system_reset)
. = 0x200
_machine_check_pSeries:
HMT_MEDIUM
mtspr SPRG1,r13 /* save r13 */
RUNLATCH_ON(r13)
EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common)
. = 0x300
.globl data_access_pSeries
data_access_pSeries:
HMT_MEDIUM
mtspr SPRG1,r13
BEGIN_FTR_SECTION
mtspr SPRG2,r12
mfspr r13,DAR
mfspr r12,DSISR
srdi r13,r13,60
rlwimi r13,r12,16,0x20
mfcr r12
cmpwi r13,0x2c
beq .do_stab_bolted_pSeries
mtcrf 0x80,r12
mfspr r12,SPRG2
END_FTR_SECTION_IFCLR(CPU_FTR_SLB)
EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, data_access_common)
. = 0x380
.globl data_access_slb_pSeries
data_access_slb_pSeries:
HMT_MEDIUM
mtspr SPRG1,r13
RUNLATCH_ON(r13)
mfspr r13,SPRG3 /* get paca address into r13 */
std r9,PACA_EXSLB+EX_R9(r13) /* save r9 - r12 */
std r10,PACA_EXSLB+EX_R10(r13)
std r11,PACA_EXSLB+EX_R11(r13)
std r12,PACA_EXSLB+EX_R12(r13)
std r3,PACA_EXSLB+EX_R3(r13)
mfspr r9,SPRG1
std r9,PACA_EXSLB+EX_R13(r13)
mfcr r9
mfspr r12,SRR1 /* and SRR1 */
mfspr r3,DAR
b .do_slb_miss /* Rel. branch works in real mode */
STD_EXCEPTION_PSERIES(0x400, instruction_access)
. = 0x480
.globl instruction_access_slb_pSeries
instruction_access_slb_pSeries:
HMT_MEDIUM
mtspr SPRG1,r13
RUNLATCH_ON(r13)
mfspr r13,SPRG3 /* get paca address into r13 */
std r9,PACA_EXSLB+EX_R9(r13) /* save r9 - r12 */
std r10,PACA_EXSLB+EX_R10(r13)
std r11,PACA_EXSLB+EX_R11(r13)
std r12,PACA_EXSLB+EX_R12(r13)
std r3,PACA_EXSLB+EX_R3(r13)
mfspr r9,SPRG1
std r9,PACA_EXSLB+EX_R13(r13)
mfcr r9
mfspr r12,SRR1 /* and SRR1 */
mfspr r3,SRR0 /* SRR0 is faulting address */
b .do_slb_miss /* Rel. branch works in real mode */
STD_EXCEPTION_PSERIES(0x500, hardware_interrupt)
STD_EXCEPTION_PSERIES(0x600, alignment)
STD_EXCEPTION_PSERIES(0x700, program_check)
STD_EXCEPTION_PSERIES(0x800, fp_unavailable)
STD_EXCEPTION_PSERIES(0x900, decrementer)
STD_EXCEPTION_PSERIES(0xa00, trap_0a)
STD_EXCEPTION_PSERIES(0xb00, trap_0b)
. = 0xc00
.globl system_call_pSeries
system_call_pSeries:
HMT_MEDIUM
RUNLATCH_ON(r9)
mr r9,r13
mfmsr r10
mfspr r13,SPRG3
mfspr r11,SRR0
clrrdi r12,r13,32
oris r12,r12,system_call_common@h
ori r12,r12,system_call_common@l
mtspr SRR0,r12
ori r10,r10,MSR_IR|MSR_DR|MSR_RI
mfspr r12,SRR1
mtspr SRR1,r10
rfid
b . /* prevent speculative execution */
STD_EXCEPTION_PSERIES(0xd00, single_step)
STD_EXCEPTION_PSERIES(0xe00, trap_0e)
/* We need to deal with the Altivec unavailable exception
* here which is at 0xf20, thus in the middle of the
* prolog code of the PerformanceMonitor one. A little
* trickery is thus necessary
*/
. = 0xf00
b performance_monitor_pSeries
STD_EXCEPTION_PSERIES(0xf20, altivec_unavailable)
STD_EXCEPTION_PSERIES(0x1300, instruction_breakpoint)
STD_EXCEPTION_PSERIES(0x1700, altivec_assist)
. = 0x3000
/*** pSeries interrupt support ***/
/* moved from 0xf00 */
STD_EXCEPTION_PSERIES(., performance_monitor)
.align 7
_GLOBAL(do_stab_bolted_pSeries)
mtcrf 0x80,r12
mfspr r12,SPRG2
EXCEPTION_PROLOG_PSERIES(PACA_EXSLB, .do_stab_bolted)
/*
* Vectors for the FWNMI option. Share common code.
*/
.globl system_reset_fwnmi
system_reset_fwnmi:
HMT_MEDIUM
mtspr SPRG1,r13 /* save r13 */
RUNLATCH_ON(r13)
EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common)
.globl machine_check_fwnmi
machine_check_fwnmi:
HMT_MEDIUM
mtspr SPRG1,r13 /* save r13 */
RUNLATCH_ON(r13)
EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common)
#ifdef CONFIG_PPC_ISERIES
/*** ISeries-LPAR interrupt handlers ***/
STD_EXCEPTION_ISERIES(0x200, machine_check, PACA_EXMC)
.globl data_access_iSeries
data_access_iSeries:
mtspr SPRG1,r13
BEGIN_FTR_SECTION
mtspr SPRG2,r12
mfspr r13,DAR
mfspr r12,DSISR
srdi r13,r13,60
rlwimi r13,r12,16,0x20
mfcr r12
cmpwi r13,0x2c
beq .do_stab_bolted_iSeries
mtcrf 0x80,r12
mfspr r12,SPRG2
END_FTR_SECTION_IFCLR(CPU_FTR_SLB)
EXCEPTION_PROLOG_ISERIES_1(PACA_EXGEN)
EXCEPTION_PROLOG_ISERIES_2
b data_access_common
.do_stab_bolted_iSeries:
mtcrf 0x80,r12
mfspr r12,SPRG2
EXCEPTION_PROLOG_ISERIES_1(PACA_EXSLB)
EXCEPTION_PROLOG_ISERIES_2
b .do_stab_bolted
.globl data_access_slb_iSeries
data_access_slb_iSeries:
mtspr SPRG1,r13 /* save r13 */
EXCEPTION_PROLOG_ISERIES_1(PACA_EXSLB)
std r3,PACA_EXSLB+EX_R3(r13)
ld r12,PACALPPACA+LPPACASRR1(r13)
mfspr r3,DAR
b .do_slb_miss
STD_EXCEPTION_ISERIES(0x400, instruction_access, PACA_EXGEN)
.globl instruction_access_slb_iSeries
instruction_access_slb_iSeries:
mtspr SPRG1,r13 /* save r13 */
EXCEPTION_PROLOG_ISERIES_1(PACA_EXSLB)
std r3,PACA_EXSLB+EX_R3(r13)
ld r12,PACALPPACA+LPPACASRR1(r13)
ld r3,PACALPPACA+LPPACASRR0(r13)
b .do_slb_miss
MASKABLE_EXCEPTION_ISERIES(0x500, hardware_interrupt)
STD_EXCEPTION_ISERIES(0x600, alignment, PACA_EXGEN)
STD_EXCEPTION_ISERIES(0x700, program_check, PACA_EXGEN)
STD_EXCEPTION_ISERIES(0x800, fp_unavailable, PACA_EXGEN)
MASKABLE_EXCEPTION_ISERIES(0x900, decrementer)
STD_EXCEPTION_ISERIES(0xa00, trap_0a, PACA_EXGEN)
STD_EXCEPTION_ISERIES(0xb00, trap_0b, PACA_EXGEN)
.globl system_call_iSeries
system_call_iSeries:
mr r9,r13
mfspr r13,SPRG3
EXCEPTION_PROLOG_ISERIES_2
b system_call_common
STD_EXCEPTION_ISERIES( 0xd00, single_step, PACA_EXGEN)
STD_EXCEPTION_ISERIES( 0xe00, trap_0e, PACA_EXGEN)
STD_EXCEPTION_ISERIES( 0xf00, performance_monitor, PACA_EXGEN)
.globl system_reset_iSeries
system_reset_iSeries:
mfspr r13,SPRG3 /* Get paca address */
mfmsr r24
ori r24,r24,MSR_RI
mtmsrd r24 /* RI on */
lhz r24,PACAPACAINDEX(r13) /* Get processor # */
cmpwi 0,r24,0 /* Are we processor 0? */
beq .__start_initialization_iSeries /* Start up the first processor */
mfspr r4,SPRN_CTRLF
li r5,CTRL_RUNLATCH /* Turn off the run light */
andc r4,r4,r5
mtspr SPRN_CTRLT,r4
1:
HMT_LOW
#ifdef CONFIG_SMP
lbz r23,PACAPROCSTART(r13) /* Test if this processor
* should start */
sync
LOADADDR(r3,current_set)
sldi r28,r24,3 /* get current_set[cpu#] */
ldx r3,r3,r28
addi r1,r3,THREAD_SIZE
subi r1,r1,STACK_FRAME_OVERHEAD
cmpwi 0,r23,0
beq iSeries_secondary_smp_loop /* Loop until told to go */
bne .__secondary_start /* Loop until told to go */
iSeries_secondary_smp_loop:
/* Let the Hypervisor know we are alive */
/* 8002 is a call to HvCallCfg::getLps, a harmless Hypervisor function */
lis r3,0x8002
rldicr r3,r3,32,15 /* r0 = (r3 << 32) & 0xffff000000000000 */
#else /* CONFIG_SMP */
/* Yield the processor. This is required for non-SMP kernels
which are running on multi-threaded machines. */
lis r3,0x8000
rldicr r3,r3,32,15 /* r3 = (r3 << 32) & 0xffff000000000000 */
addi r3,r3,18 /* r3 = 0x8000000000000012 which is "yield" */
li r4,0 /* "yield timed" */
li r5,-1 /* "yield forever" */
#endif /* CONFIG_SMP */
li r0,-1 /* r0=-1 indicates a Hypervisor call */
sc /* Invoke the hypervisor via a system call */
mfspr r13,SPRG3 /* Put r13 back ???? */
b 1b /* If SMP not configured, secondaries
* loop forever */
.globl decrementer_iSeries_masked
decrementer_iSeries_masked:
li r11,1
stb r11,PACALPPACA+LPPACADECRINT(r13)
lwz r12,PACADEFAULTDECR(r13)
mtspr SPRN_DEC,r12
/* fall through */
.globl hardware_interrupt_iSeries_masked
hardware_interrupt_iSeries_masked:
mtcrf 0x80,r9 /* Restore regs */
ld r11,PACALPPACA+LPPACASRR0(r13)
ld r12,PACALPPACA+LPPACASRR1(r13)
mtspr SRR0,r11
mtspr SRR1,r12
ld r9,PACA_EXGEN+EX_R9(r13)
ld r10,PACA_EXGEN+EX_R10(r13)
ld r11,PACA_EXGEN+EX_R11(r13)
ld r12,PACA_EXGEN+EX_R12(r13)
ld r13,PACA_EXGEN+EX_R13(r13)
rfid
b . /* prevent speculative execution */
#endif /* CONFIG_PPC_ISERIES */
/*** Common interrupt handlers ***/
STD_EXCEPTION_COMMON(0x100, system_reset, .system_reset_exception)
/*
* Machine check is different because we use a different
* save area: PACA_EXMC instead of PACA_EXGEN.
*/
.align 7
.globl machine_check_common
machine_check_common:
EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
DISABLE_INTS
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl .machine_check_exception
b .ret_from_except
STD_EXCEPTION_COMMON_LITE(0x900, decrementer, .timer_interrupt)
STD_EXCEPTION_COMMON(0xa00, trap_0a, .unknown_exception)
STD_EXCEPTION_COMMON(0xb00, trap_0b, .unknown_exception)
STD_EXCEPTION_COMMON(0xd00, single_step, .single_step_exception)
STD_EXCEPTION_COMMON(0xe00, trap_0e, .unknown_exception)
STD_EXCEPTION_COMMON(0xf00, performance_monitor, .performance_monitor_exception)
STD_EXCEPTION_COMMON(0x1300, instruction_breakpoint, .instruction_breakpoint_exception)
#ifdef CONFIG_ALTIVEC
STD_EXCEPTION_COMMON(0x1700, altivec_assist, .altivec_assist_exception)
#else
STD_EXCEPTION_COMMON(0x1700, altivec_assist, .unknown_exception)
#endif
/*
* Here we have detected that the kernel stack pointer is bad.
* R9 contains the saved CR, r13 points to the paca,
* r10 contains the (bad) kernel stack pointer,
* r11 and r12 contain the saved SRR0 and SRR1.
* We switch to using an emergency stack, save the registers there,
* and call kernel_bad_stack(), which panics.
*/
bad_stack:
ld r1,PACAEMERGSP(r13)
subi r1,r1,64+INT_FRAME_SIZE
std r9,_CCR(r1)
std r10,GPR1(r1)
std r11,_NIP(r1)
std r12,_MSR(r1)
mfspr r11,DAR
mfspr r12,DSISR
std r11,_DAR(r1)
std r12,_DSISR(r1)
mflr r10
mfctr r11
mfxer r12
std r10,_LINK(r1)
std r11,_CTR(r1)
std r12,_XER(r1)
SAVE_GPR(0,r1)
SAVE_GPR(2,r1)
SAVE_4GPRS(3,r1)
SAVE_2GPRS(7,r1)
SAVE_10GPRS(12,r1)
SAVE_10GPRS(22,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
/*
* Return from an exception with minimal checks.
* The caller is assumed to have done EXCEPTION_PROLOG_COMMON.
* If interrupts have been enabled, or anything has been
* done that might have changed the scheduling status of
* any task or sent any task a signal, you should use
* ret_from_except or ret_from_except_lite instead of this.
*/
fast_exception_return:
ld r12,_MSR(r1)
ld r11,_NIP(r1)
andi. r3,r12,MSR_RI /* check if RI is set */
beq- unrecov_fer
ld r3,_CCR(r1)
ld r4,_LINK(r1)
ld r5,_CTR(r1)
ld r6,_XER(r1)
mtcr r3
mtlr r4
mtctr r5
mtxer r6
REST_GPR(0, r1)
REST_8GPRS(2, r1)
mfmsr r10
clrrdi r10,r10,2 /* clear RI (LE is 0 already) */
mtmsrd r10,1
mtspr SRR1,r12
mtspr SRR0,r11
REST_4GPRS(10, r1)
ld r1,GPR1(r1)
rfid
b . /* prevent speculative execution */
unrecov_fer:
bl .save_nvgprs
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl .unrecoverable_exception
b 1b
/*
* Here r13 points to the paca, r9 contains the saved CR,
* SRR0 and SRR1 are saved in r11 and r12,
* r9 - r13 are saved in paca->exgen.
*/
.align 7
.globl data_access_common
data_access_common:
RUNLATCH_ON(r10) /* It wont fit in the 0x300 handler */
mfspr r10,DAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,DSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0x300, PACA_EXGEN)
ld r3,PACA_EXGEN+EX_DAR(r13)
lwz r4,PACA_EXGEN+EX_DSISR(r13)
li r5,0x300
b .do_hash_page /* Try to handle as hpte fault */
.align 7
.globl instruction_access_common
instruction_access_common:
EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
ld r3,_NIP(r1)
andis. r4,r12,0x5820
li r5,0x400
b .do_hash_page /* Try to handle as hpte fault */
.align 7
.globl hardware_interrupt_common
.globl hardware_interrupt_entry
hardware_interrupt_common:
EXCEPTION_PROLOG_COMMON(0x500, PACA_EXGEN)
hardware_interrupt_entry:
DISABLE_INTS
addi r3,r1,STACK_FRAME_OVERHEAD
bl .do_IRQ
b .ret_from_except_lite
.align 7
.globl alignment_common
alignment_common:
mfspr r10,DAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,DSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0x600, PACA_EXGEN)
ld r3,PACA_EXGEN+EX_DAR(r13)
lwz r4,PACA_EXGEN+EX_DSISR(r13)
std r3,_DAR(r1)
std r4,_DSISR(r1)
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
ENABLE_INTS
bl .alignment_exception
b .ret_from_except
.align 7
.globl program_check_common
program_check_common:
EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
ENABLE_INTS
bl .program_check_exception
b .ret_from_except
.align 7
.globl fp_unavailable_common
fp_unavailable_common:
EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
bne .load_up_fpu /* if from user, just load it up */
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
ENABLE_INTS
bl .kernel_fp_unavailable_exception
BUG_OPCODE
/*
* load_up_fpu(unused, unused, tsk)
* Disable FP for the task which had the FPU previously,
* and save its floating-point registers in its thread_struct.
* Enables the FPU for use in the kernel on return.
* On SMP we know the fpu is free, since we give it up every
* switch (ie, no lazy save of the FP registers).
* On entry: r13 == 'current' && last_task_used_math != 'current'
*/
_STATIC(load_up_fpu)
mfmsr r5 /* grab the current MSR */
ori r5,r5,MSR_FP
mtmsrd r5 /* enable use of fpu now */
isync
/*
* For SMP, we don't do lazy FPU switching because it just gets too
* horrendously complex, especially when a task switches from one CPU
* to another. Instead we call giveup_fpu in switch_to.
*
*/
#ifndef CONFIG_SMP
ld r3,last_task_used_math@got(r2)
ld r4,0(r3)
cmpdi 0,r4,0
beq 1f
/* Save FP state to last_task_used_math's THREAD struct */
addi r4,r4,THREAD
SAVE_32FPRS(0, r4)
mffs fr0
stfd fr0,THREAD_FPSCR(r4)
/* Disable FP for last_task_used_math */
ld r5,PT_REGS(r4)
ld r4,_MSR-STACK_FRAME_OVERHEAD(r5)
li r6,MSR_FP|MSR_FE0|MSR_FE1
andc r4,r4,r6
std r4,_MSR-STACK_FRAME_OVERHEAD(r5)
1:
#endif /* CONFIG_SMP */
/* enable use of FP after return */
ld r4,PACACURRENT(r13)
addi r5,r4,THREAD /* Get THREAD */
ld r4,THREAD_FPEXC_MODE(r5)
ori r12,r12,MSR_FP
or r12,r12,r4
std r12,_MSR(r1)
lfd fr0,THREAD_FPSCR(r5)
mtfsf 0xff,fr0
REST_32FPRS(0, r5)
#ifndef CONFIG_SMP
/* Update last_task_used_math to 'current' */
subi r4,r5,THREAD /* Back to 'current' */
std r4,0(r3)
#endif /* CONFIG_SMP */
/* restore registers and return */
b fast_exception_return
.align 7
.globl altivec_unavailable_common
altivec_unavailable_common:
EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
#ifdef CONFIG_ALTIVEC
BEGIN_FTR_SECTION
bne .load_up_altivec /* if from user, just load it up */
END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
#endif
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
ENABLE_INTS
bl .altivec_unavailable_exception
b .ret_from_except
#ifdef CONFIG_ALTIVEC
/*
* load_up_altivec(unused, unused, tsk)
* Disable VMX for the task which had it previously,
* and save its vector registers in its thread_struct.
* Enables the VMX for use in the kernel on return.
* On SMP we know the VMX is free, since we give it up every
* switch (ie, no lazy save of the vector registers).
* On entry: r13 == 'current' && last_task_used_altivec != 'current'
*/
_STATIC(load_up_altivec)
mfmsr r5 /* grab the current MSR */
oris r5,r5,MSR_VEC@h
mtmsrd r5 /* enable use of VMX now */
isync
/*
* For SMP, we don't do lazy VMX switching because it just gets too
* horrendously complex, especially when a task switches from one CPU
* to another. Instead we call giveup_altvec in switch_to.
* VRSAVE isn't dealt with here, that is done in the normal context
* switch code. Note that we could rely on vrsave value to eventually
* avoid saving all of the VREGs here...
*/
#ifndef CONFIG_SMP
ld r3,last_task_used_altivec@got(r2)
ld r4,0(r3)
cmpdi 0,r4,0
beq 1f
/* Save VMX state to last_task_used_altivec's THREAD struct */
addi r4,r4,THREAD
SAVE_32VRS(0,r5,r4)
mfvscr vr0
li r10,THREAD_VSCR
stvx vr0,r10,r4
/* Disable VMX for last_task_used_altivec */
ld r5,PT_REGS(r4)
ld r4,_MSR-STACK_FRAME_OVERHEAD(r5)
lis r6,MSR_VEC@h
andc r4,r4,r6
std r4,_MSR-STACK_FRAME_OVERHEAD(r5)
1:
#endif /* CONFIG_SMP */
/* Hack: if we get an altivec unavailable trap with VRSAVE
* set to all zeros, we assume this is a broken application
* that fails to set it properly, and thus we switch it to
* all 1's
*/
mfspr r4,SPRN_VRSAVE
cmpdi 0,r4,0
bne+ 1f
li r4,-1
mtspr SPRN_VRSAVE,r4
1:
/* enable use of VMX after return */
ld r4,PACACURRENT(r13)
addi r5,r4,THREAD /* Get THREAD */
oris r12,r12,MSR_VEC@h
std r12,_MSR(r1)
li r4,1
li r10,THREAD_VSCR
stw r4,THREAD_USED_VR(r5)
lvx vr0,r10,r5
mtvscr vr0
REST_32VRS(0,r4,r5)
#ifndef CONFIG_SMP
/* Update last_task_used_math to 'current' */
subi r4,r5,THREAD /* Back to 'current' */
std r4,0(r3)
#endif /* CONFIG_SMP */
/* restore registers and return */
b fast_exception_return
#endif /* CONFIG_ALTIVEC */
/*
* Hash table stuff
*/
.align 7
_GLOBAL(do_hash_page)
std r3,_DAR(r1)
std r4,_DSISR(r1)
andis. r0,r4,0xa450 /* weird error? */
bne- .handle_page_fault /* if not, try to insert a HPTE */
BEGIN_FTR_SECTION
andis. r0,r4,0x0020 /* Is it a segment table fault? */
bne- .do_ste_alloc /* If so handle it */
END_FTR_SECTION_IFCLR(CPU_FTR_SLB)
/*
* We need to set the _PAGE_USER bit if MSR_PR is set or if we are
* accessing a userspace segment (even from the kernel). We assume
* kernel addresses always have the high bit set.
*/
rlwinm r4,r4,32-25+9,31-9,31-9 /* DSISR_STORE -> _PAGE_RW */
rotldi r0,r3,15 /* Move high bit into MSR_PR posn */
orc r0,r12,r0 /* MSR_PR | ~high_bit */
rlwimi r4,r0,32-13,30,30 /* becomes _PAGE_USER access bit */
ori r4,r4,1 /* add _PAGE_PRESENT */
rlwimi r4,r5,22+2,31-2,31-2 /* Set _PAGE_EXEC if trap is 0x400 */
/*
* On iSeries, we soft-disable interrupts here, then
* hard-enable interrupts so that the hash_page code can spin on
* the hash_table_lock without problems on a shared processor.
*/
DISABLE_INTS
/*
* r3 contains the faulting address
* r4 contains the required access permissions
* r5 contains the trap number
*
* at return r3 = 0 for success
*/
bl .hash_page /* build HPTE if possible */
cmpdi r3,0 /* see if hash_page succeeded */
#ifdef DO_SOFT_DISABLE
/*
* If we had interrupts soft-enabled at the point where the
* DSI/ISI occurred, and an interrupt came in during hash_page,
* handle it now.
* We jump to ret_from_except_lite rather than fast_exception_return
* because ret_from_except_lite will check for and handle pending
* interrupts if necessary.
*/
beq .ret_from_except_lite
/* For a hash failure, we don't bother re-enabling interrupts */
ble- 12f
/*
* hash_page couldn't handle it, set soft interrupt enable back
* to what it was before the trap. Note that .local_irq_restore
* handles any interrupts pending at this point.
*/
ld r3,SOFTE(r1)
bl .local_irq_restore
b 11f
#else
beq fast_exception_return /* Return from exception on success */
ble- 12f /* Failure return from hash_page */
/* fall through */
#endif
/* Here we have a page fault that hash_page can't handle. */
_GLOBAL(handle_page_fault)
ENABLE_INTS
11: ld r4,_DAR(r1)
ld r5,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
bl .do_page_fault
cmpdi r3,0
beq+ .ret_from_except_lite
bl .save_nvgprs
mr r5,r3
addi r3,r1,STACK_FRAME_OVERHEAD
lwz r4,_DAR(r1)
bl .bad_page_fault
b .ret_from_except
/* We have a page fault that hash_page could handle but HV refused
* the PTE insertion
*/
12: bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
lwz r4,_DAR(r1)
bl .low_hash_fault
b .ret_from_except
/* here we have a segment miss */
_GLOBAL(do_ste_alloc)
bl .ste_allocate /* try to insert stab entry */
cmpdi r3,0
beq+ fast_exception_return
b .handle_page_fault
/*
* r13 points to the PACA, r9 contains the saved CR,
* r11 and r12 contain the saved SRR0 and SRR1.
* r9 - r13 are saved in paca->exslb.
* We assume we aren't going to take any exceptions during this procedure.
* We assume (DAR >> 60) == 0xc.
*/
.align 7
_GLOBAL(do_stab_bolted)
stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */
std r11,PACA_EXSLB+EX_SRR0(r13) /* save SRR0 in exc. frame */
/* Hash to the primary group */
ld r10,PACASTABVIRT(r13)
mfspr r11,DAR
srdi r11,r11,28
rldimi r10,r11,7,52 /* r10 = first ste of the group */
/* Calculate VSID */
/* This is a kernel address, so protovsid = ESID */
ASM_VSID_SCRAMBLE(r11, r9)
rldic r9,r11,12,16 /* r9 = vsid << 12 */
/* Search the primary group for a free entry */
1: ld r11,0(r10) /* Test valid bit of the current ste */
andi. r11,r11,0x80
beq 2f
addi r10,r10,16
andi. r11,r10,0x70
bne 1b
/* Stick for only searching the primary group for now. */
/* At least for now, we use a very simple random castout scheme */
/* Use the TB as a random number ; OR in 1 to avoid entry 0 */
mftb r11
rldic r11,r11,4,57 /* r11 = (r11 << 4) & 0x70 */
ori r11,r11,0x10
/* r10 currently points to an ste one past the group of interest */
/* make it point to the randomly selected entry */
subi r10,r10,128
or r10,r10,r11 /* r10 is the entry to invalidate */
isync /* mark the entry invalid */
ld r11,0(r10)
rldicl r11,r11,56,1 /* clear the valid bit */
rotldi r11,r11,8
std r11,0(r10)
sync
clrrdi r11,r11,28 /* Get the esid part of the ste */
slbie r11
2: std r9,8(r10) /* Store the vsid part of the ste */
eieio
mfspr r11,DAR /* Get the new esid */
clrrdi r11,r11,28 /* Permits a full 32b of ESID */
ori r11,r11,0x90 /* Turn on valid and kp */
std r11,0(r10) /* Put new entry back into the stab */
sync
/* All done -- return from exception. */
lwz r9,PACA_EXSLB+EX_CCR(r13) /* get saved CR */
ld r11,PACA_EXSLB+EX_SRR0(r13) /* get saved SRR0 */
andi. r10,r12,MSR_RI
beq- unrecov_slb
mtcrf 0x80,r9 /* restore CR */
mfmsr r10
clrrdi r10,r10,2
mtmsrd r10,1
mtspr SRR0,r11
mtspr SRR1,r12
ld r9,PACA_EXSLB+EX_R9(r13)
ld r10,PACA_EXSLB+EX_R10(r13)
ld r11,PACA_EXSLB+EX_R11(r13)
ld r12,PACA_EXSLB+EX_R12(r13)
ld r13,PACA_EXSLB+EX_R13(r13)
rfid
b . /* prevent speculative execution */
/*
* r13 points to the PACA, r9 contains the saved CR,
* r11 and r12 contain the saved SRR0 and SRR1.
* r3 has the faulting address
* r9 - r13 are saved in paca->exslb.
* r3 is saved in paca->slb_r3
* We assume we aren't going to take any exceptions during this procedure.
*/
_GLOBAL(do_slb_miss)
mflr r10
stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */
std r10,PACA_EXSLB+EX_LR(r13) /* save LR */
bl .slb_allocate /* handle it */
/* All done -- return from exception. */
ld r10,PACA_EXSLB+EX_LR(r13)
ld r3,PACA_EXSLB+EX_R3(r13)
lwz r9,PACA_EXSLB+EX_CCR(r13) /* get saved CR */
#ifdef CONFIG_PPC_ISERIES
ld r11,PACALPPACA+LPPACASRR0(r13) /* get SRR0 value */
#endif /* CONFIG_PPC_ISERIES */
mtlr r10
andi. r10,r12,MSR_RI /* check for unrecoverable exception */
beq- unrecov_slb
.machine push
.machine "power4"
mtcrf 0x80,r9
mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */
.machine pop
#ifdef CONFIG_PPC_ISERIES
mtspr SRR0,r11
mtspr SRR1,r12
#endif /* CONFIG_PPC_ISERIES */
ld r9,PACA_EXSLB+EX_R9(r13)
ld r10,PACA_EXSLB+EX_R10(r13)
ld r11,PACA_EXSLB+EX_R11(r13)
ld r12,PACA_EXSLB+EX_R12(r13)
ld r13,PACA_EXSLB+EX_R13(r13)
rfid
b . /* prevent speculative execution */
unrecov_slb:
EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
DISABLE_INTS
bl .save_nvgprs
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl .unrecoverable_exception
b 1b
/*
* Space for CPU0's segment table.
*
* On iSeries, the hypervisor must fill in at least one entry before
* we get control (with relocate on). The address is give to the hv
* as a page number (see xLparMap in LparData.c), so this must be at a
* fixed address (the linker can't compute (u64)&initial_stab >>
* PAGE_SHIFT).
*/
. = STAB0_PHYS_ADDR /* 0x6000 */
.globl initial_stab
initial_stab:
.space 4096
/*
* Data area reserved for FWNMI option.
* This address (0x7000) is fixed by the RPA.
*/
.= 0x7000
.globl fwnmi_data_area
fwnmi_data_area:
/* iSeries does not use the FWNMI stuff, so it is safe to put
* this here, even if we later allow kernels that will boot on
* both pSeries and iSeries */
#ifdef CONFIG_PPC_ISERIES
. = LPARMAP_PHYS
#include "lparmap.s"
/*
* This ".text" is here for old compilers that generate a trailing
* .note section when compiling .c files to .s
*/
.text
#endif /* CONFIG_PPC_ISERIES */
. = 0x8000
/*
* On pSeries, secondary processors spin in the following code.
* At entry, r3 = this processor's number (physical cpu id)
*/
_GLOBAL(pSeries_secondary_smp_init)
mr r24,r3
/* turn on 64-bit mode */
bl .enable_64b_mode
isync
/* Copy some CPU settings from CPU 0 */
bl .__restore_cpu_setup
/* Set up a paca value for this processor. Since we have the
[PATCH] ppc64: kexec support for ppc64 This patch implements the kexec support for ppc64 platforms. A couple of notes: 1) We copy the pages in virtual mode, using the full base kernel and a statically allocated stack. At kexec_prepare time we scan the pages and if any overlap our (0, _end[]) range we return -ETXTBSY. On PowerPC 64 systems running in LPAR (logical partitioning) mode, only a small region of memory, referred to as the RMO, can be accessed in real mode. Since Linux runs with only one zone of memory in the memory allocator, and it can be orders of magnitude more memory than the RMO, looping until we allocate pages in the source region is not feasible. Copying in virtual means we don't have to write a hash table generation and call hypervisor to insert translations, instead we rely on the pinned kernel linear mapping. The kernel already has move to linked location built in, so there is no requirement to load it at 0. If we want to load something other than a kernel, then a stub can be written to copy a linear chunk in real mode. 2) The start entry point gets passed parameters from the kernel. Slaves are started at a fixed address after copying code from the entry point. All CPUs get passed their firmware assigned physical id in r3 (most calling conventions use this register for the first argument). This is used to distinguish each CPU from all other CPUs. Since firmware is not around, there is no other way to obtain this information other than to pass it somewhere. A single CPU, referred to here as the master and the one executing the kexec call, branches to start with the address of start in r4. While this can be calculated, we have to load it through a gpr to branch to this point so defining the register this is contained in is free. A stack of unspecified size is available at r1 (also common calling convention). All remaining running CPUs are sent to start at absolute address 0x60 after copying the first 0x100 bytes from start to address 0. This convention was chosen because it matches what the kernel has been doing itself. (only gpr3 is defined). Note: This is not quite the convention of the kexec bootblock v2 in the kernel. A stub has been written to convert between them, and we may adjust the kernel in the future to allow this directly without any stub. 3) Destination pages can be placed anywhere, even where they would not be accessible in real mode. This will allow us to place ram disks above the RMO if we choose. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: R Sharada <sharada@in.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 17:58:10 -04:00
* physical cpu id in r24, we need to search the pacas to find
* which logical id maps to our physical one.
*/
LOADADDR(r13, paca) /* Get base vaddr of paca array */
li r5,0 /* logical cpu id */
1: lhz r6,PACAHWCPUID(r13) /* Load HW procid from paca */
cmpw r6,r24 /* Compare to our id */
beq 2f
addi r13,r13,PACA_SIZE /* Loop to next PACA on miss */
addi r5,r5,1
cmpwi r5,NR_CPUS
blt 1b
[PATCH] ppc64: kexec support for ppc64 This patch implements the kexec support for ppc64 platforms. A couple of notes: 1) We copy the pages in virtual mode, using the full base kernel and a statically allocated stack. At kexec_prepare time we scan the pages and if any overlap our (0, _end[]) range we return -ETXTBSY. On PowerPC 64 systems running in LPAR (logical partitioning) mode, only a small region of memory, referred to as the RMO, can be accessed in real mode. Since Linux runs with only one zone of memory in the memory allocator, and it can be orders of magnitude more memory than the RMO, looping until we allocate pages in the source region is not feasible. Copying in virtual means we don't have to write a hash table generation and call hypervisor to insert translations, instead we rely on the pinned kernel linear mapping. The kernel already has move to linked location built in, so there is no requirement to load it at 0. If we want to load something other than a kernel, then a stub can be written to copy a linear chunk in real mode. 2) The start entry point gets passed parameters from the kernel. Slaves are started at a fixed address after copying code from the entry point. All CPUs get passed their firmware assigned physical id in r3 (most calling conventions use this register for the first argument). This is used to distinguish each CPU from all other CPUs. Since firmware is not around, there is no other way to obtain this information other than to pass it somewhere. A single CPU, referred to here as the master and the one executing the kexec call, branches to start with the address of start in r4. While this can be calculated, we have to load it through a gpr to branch to this point so defining the register this is contained in is free. A stack of unspecified size is available at r1 (also common calling convention). All remaining running CPUs are sent to start at absolute address 0x60 after copying the first 0x100 bytes from start to address 0. This convention was chosen because it matches what the kernel has been doing itself. (only gpr3 is defined). Note: This is not quite the convention of the kexec bootblock v2 in the kernel. A stub has been written to convert between them, and we may adjust the kernel in the future to allow this directly without any stub. 3) Destination pages can be placed anywhere, even where they would not be accessible in real mode. This will allow us to place ram disks above the RMO if we choose. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: R Sharada <sharada@in.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 17:58:10 -04:00
mr r3,r24 /* not found, copy phys to r3 */
b .kexec_wait /* next kernel might do better */
2: mtspr SPRG3,r13 /* Save vaddr of paca in SPRG3 */
/* From now on, r24 is expected to be logical cpuid */
mr r24,r5
3: HMT_LOW
lbz r23,PACAPROCSTART(r13) /* Test if this processor should */
/* start. */
sync
/* Create a temp kernel stack for use before relocation is on. */
ld r1,PACAEMERGSP(r13)
subi r1,r1,STACK_FRAME_OVERHEAD
cmpwi 0,r23,0
#ifdef CONFIG_SMP
bne .__secondary_start
#endif
b 3b /* Loop until told to go */
#ifdef CONFIG_PPC_ISERIES
_STATIC(__start_initialization_iSeries)
/* Clear out the BSS */
LOADADDR(r11,__bss_stop)
LOADADDR(r8,__bss_start)
sub r11,r11,r8 /* bss size */
addi r11,r11,7 /* round up to an even double word */
rldicl. r11,r11,61,3 /* shift right by 3 */
beq 4f
addi r8,r8,-8
li r0,0
mtctr r11 /* zero this many doublewords */
3: stdu r0,8(r8)
bdnz 3b
4:
LOADADDR(r1,init_thread_union)
addi r1,r1,THREAD_SIZE
li r0,0
stdu r0,-STACK_FRAME_OVERHEAD(r1)
LOADADDR(r3,cpu_specs)
LOADADDR(r4,cur_cpu_spec)
li r5,0
bl .identify_cpu
LOADADDR(r2,__toc_start)
addi r2,r2,0x4000
addi r2,r2,0x4000
bl .iSeries_early_setup
/* relocation is on at this point */
b .start_here_common
#endif /* CONFIG_PPC_ISERIES */
#ifdef CONFIG_PPC_MULTIPLATFORM
_STATIC(__mmu_off)
mfmsr r3
andi. r0,r3,MSR_IR|MSR_DR
beqlr
andc r3,r3,r0
mtspr SPRN_SRR0,r4
mtspr SPRN_SRR1,r3
sync
rfid
b . /* prevent speculative execution */
/*
* Here is our main kernel entry point. We support currently 2 kind of entries
* depending on the value of r5.
*
* r5 != NULL -> OF entry, we go to prom_init, "legacy" parameter content
* in r3...r7
*
* r5 == NULL -> kexec style entry. r3 is a physical pointer to the
* DT block, r4 is a physical pointer to the kernel itself
*
*/
_GLOBAL(__start_initialization_multiplatform)
/*
* Are we booted from a PROM Of-type client-interface ?
*/
cmpldi cr0,r5,0
bne .__boot_from_prom /* yes -> prom */
/* Save parameters */
mr r31,r3
mr r30,r4
/* Make sure we are running in 64 bits mode */
bl .enable_64b_mode
/* Setup some critical 970 SPRs before switching MMU off */
bl .__970_cpu_preinit
/* cpu # */
li r24,0
/* Switch off MMU if not already */
LOADADDR(r4, .__after_prom_start - KERNELBASE)
add r4,r4,r30
bl .__mmu_off
b .__after_prom_start
_STATIC(__boot_from_prom)
/* Save parameters */
mr r31,r3
mr r30,r4
mr r29,r5
mr r28,r6
mr r27,r7
/* Make sure we are running in 64 bits mode */
bl .enable_64b_mode
/* put a relocation offset into r3 */
bl .reloc_offset
LOADADDR(r2,__toc_start)
addi r2,r2,0x4000
addi r2,r2,0x4000
/* Relocate the TOC from a virt addr to a real addr */
sub r2,r2,r3
/* Restore parameters */
mr r3,r31
mr r4,r30
mr r5,r29
mr r6,r28
mr r7,r27
/* Do all of the interaction with OF client interface */
bl .prom_init
/* We never return */
trap
/*
* At this point, r3 contains the physical address we are running at,
* returned by prom_init()
*/
_STATIC(__after_prom_start)
/*
* We need to run with __start at physical address 0.
* This will leave some code in the first 256B of
* real memory, which are reserved for software use.
* The remainder of the first page is loaded with the fixed
* interrupt vectors. The next two pages are filled with
* unknown exception placeholders.
*
* Note: This process overwrites the OF exception vectors.
* r26 == relocation offset
* r27 == KERNELBASE
*/
bl .reloc_offset
mr r26,r3
SET_REG_TO_CONST(r27,KERNELBASE)
li r3,0 /* target addr */
// XXX FIXME: Use phys returned by OF (r30)
sub r4,r27,r26 /* source addr */
/* current address of _start */
/* i.e. where we are running */
/* the source addr */
LOADADDR(r5,copy_to_here) /* # bytes of memory to copy */
sub r5,r5,r27
li r6,0x100 /* Start offset, the first 0x100 */
/* bytes were copied earlier. */
bl .copy_and_flush /* copy the first n bytes */
/* this includes the code being */
/* executed here. */
LOADADDR(r0, 4f) /* Jump to the copy of this code */
mtctr r0 /* that we just made/relocated */
bctr
4: LOADADDR(r5,klimit)
sub r5,r5,r26
ld r5,0(r5) /* get the value of klimit */
sub r5,r5,r27
bl .copy_and_flush /* copy the rest */
b .start_here_multiplatform
#endif /* CONFIG_PPC_MULTIPLATFORM */
/*
* Copy routine used to copy the kernel to start at physical address 0
* and flush and invalidate the caches as needed.
* r3 = dest addr, r4 = source addr, r5 = copy limit, r6 = start offset
* on exit, r3, r4, r5 are unchanged, r6 is updated to be >= r5.
*
* Note: this routine *only* clobbers r0, r6 and lr
*/
_GLOBAL(copy_and_flush)
addi r5,r5,-8
addi r6,r6,-8
4: li r0,16 /* Use the least common */
/* denominator cache line */
/* size. This results in */
/* extra cache line flushes */
/* but operation is correct. */
/* Can't get cache line size */
/* from NACA as it is being */
/* moved too. */
mtctr r0 /* put # words/line in ctr */
3: addi r6,r6,8 /* copy a cache line */
ldx r0,r6,r4
stdx r0,r6,r3
bdnz 3b
dcbst r6,r3 /* write it to memory */
sync
icbi r6,r3 /* flush the icache line */
cmpld 0,r6,r5
blt 4b
sync
addi r5,r5,8
addi r6,r6,8
blr
.align 8
copy_to_here:
#ifdef CONFIG_SMP
#ifdef CONFIG_PPC_PMAC
/*
* On PowerMac, secondary processors starts from the reset vector, which
* is temporarily turned into a call to one of the functions below.
*/
.section ".text";
.align 2 ;
.globl pmac_secondary_start_1
pmac_secondary_start_1:
li r24, 1
b .pmac_secondary_start
.globl pmac_secondary_start_2
pmac_secondary_start_2:
li r24, 2
b .pmac_secondary_start
.globl pmac_secondary_start_3
pmac_secondary_start_3:
li r24, 3
b .pmac_secondary_start
_GLOBAL(pmac_secondary_start)
/* turn on 64-bit mode */
bl .enable_64b_mode
isync
/* Copy some CPU settings from CPU 0 */
bl .__restore_cpu_setup
/* pSeries do that early though I don't think we really need it */
mfmsr r3
ori r3,r3,MSR_RI
mtmsrd r3 /* RI on */
/* Set up a paca value for this processor. */
LOADADDR(r4, paca) /* Get base vaddr of paca array */
mulli r13,r24,PACA_SIZE /* Calculate vaddr of right paca */
add r13,r13,r4 /* for this processor. */
mtspr SPRG3,r13 /* Save vaddr of paca in SPRG3 */
/* Create a temp kernel stack for use before relocation is on. */
ld r1,PACAEMERGSP(r13)
subi r1,r1,STACK_FRAME_OVERHEAD
b .__secondary_start
#endif /* CONFIG_PPC_PMAC */
/*
* This function is called after the master CPU has released the
* secondary processors. The execution environment is relocation off.
* The paca for this processor has the following fields initialized at
* this point:
* 1. Processor number
* 2. Segment table pointer (virtual address)
* On entry the following are set:
* r1 = stack pointer. vaddr for iSeries, raddr (temp stack) for pSeries
* r24 = cpu# (in Linux terms)
* r13 = paca virtual address
* SPRG3 = paca virtual address
*/
_GLOBAL(__secondary_start)
HMT_MEDIUM /* Set thread priority to MEDIUM */
ld r2,PACATOC(r13)
li r6,0
stb r6,PACAPROCENABLED(r13)
#ifndef CONFIG_PPC_ISERIES
/* Initialize the page table pointer register. */
LOADADDR(r6,_SDR1)
ld r6,0(r6) /* get the value of _SDR1 */
mtspr SDR1,r6 /* set the htab location */
#endif
/* Initialize the first segment table (or SLB) entry */
ld r3,PACASTABVIRT(r13) /* get addr of segment table */
bl .stab_initialize
/* Initialize the kernel stack. Just a repeat for iSeries. */
LOADADDR(r3,current_set)
sldi r28,r24,3 /* get current_set[cpu#] */
ldx r1,r3,r28
addi r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
std r1,PACAKSAVE(r13)
ld r3,PACASTABREAL(r13) /* get raddr of segment table */
ori r4,r3,1 /* turn on valid bit */
#ifdef CONFIG_PPC_ISERIES
li r0,-1 /* hypervisor call */
li r3,1
sldi r3,r3,63 /* 0x8000000000000000 */
ori r3,r3,4 /* 0x8000000000000004 */
sc /* HvCall_setASR */
#else
/* set the ASR */
ld r3,systemcfg@got(r2) /* r3 = ptr to systemcfg */
ld r3,0(r3)
lwz r3,PLATFORM(r3) /* r3 = platform flags */
andi. r3,r3,PLATFORM_LPAR /* Test if bit 0 is set (LPAR bit) */
bne 98f
mfspr r3,PVR
srwi r3,r3,16
cmpwi r3,0x37 /* SStar */
beq 97f
cmpwi r3,0x36 /* IStar */
beq 97f
cmpwi r3,0x34 /* Pulsar */
bne 98f
97: li r3,H_SET_ASR /* hcall = H_SET_ASR */
HVSC /* Invoking hcall */
b 99f
98: /* !(rpa hypervisor) || !(star) */
mtasr r4 /* set the stab location */
99:
#endif
li r7,0
mtlr r7
/* enable MMU and jump to start_secondary */
LOADADDR(r3,.start_secondary_prolog)
SET_REG_TO_CONST(r4, MSR_KERNEL)
#ifdef DO_SOFT_DISABLE
ori r4,r4,MSR_EE
#endif
mtspr SRR0,r3
mtspr SRR1,r4
rfid
b . /* prevent speculative execution */
/*
* Running with relocation on at this point. All we want to do is
* zero the stack back-chain pointer before going into C code.
*/
_GLOBAL(start_secondary_prolog)
li r3,0
std r3,0(r1) /* Zero the stack frame pointer */
bl .start_secondary
#endif
/*
* This subroutine clobbers r11 and r12
*/
_GLOBAL(enable_64b_mode)
mfmsr r11 /* grab the current MSR */
li r12,1
rldicr r12,r12,MSR_SF_LG,(63-MSR_SF_LG)
or r11,r11,r12
li r12,1
rldicr r12,r12,MSR_ISF_LG,(63-MSR_ISF_LG)
or r11,r11,r12
mtmsrd r11
isync
blr
#ifdef CONFIG_PPC_MULTIPLATFORM
/*
* This is where the main kernel code starts.
*/
_STATIC(start_here_multiplatform)
/* get a new offset, now that the kernel has moved. */
bl .reloc_offset
mr r26,r3
/* Clear out the BSS. It may have been done in prom_init,
* already but that's irrelevant since prom_init will soon
* be detached from the kernel completely. Besides, we need
* to clear it now for kexec-style entry.
*/
LOADADDR(r11,__bss_stop)
LOADADDR(r8,__bss_start)
sub r11,r11,r8 /* bss size */
addi r11,r11,7 /* round up to an even double word */
rldicl. r11,r11,61,3 /* shift right by 3 */
beq 4f
addi r8,r8,-8
li r0,0
mtctr r11 /* zero this many doublewords */
3: stdu r0,8(r8)
bdnz 3b
4:
mfmsr r6
ori r6,r6,MSR_RI
mtmsrd r6 /* RI on */
#ifdef CONFIG_HMT
/* Start up the second thread on cpu 0 */
mfspr r3,PVR
srwi r3,r3,16
cmpwi r3,0x34 /* Pulsar */
beq 90f
cmpwi r3,0x36 /* Icestar */
beq 90f
cmpwi r3,0x37 /* SStar */
beq 90f
b 91f /* HMT not supported */
90: li r3,0
bl .hmt_start_secondary
91:
#endif
/* The following gets the stack and TOC set up with the regs */
/* pointing to the real addr of the kernel stack. This is */
/* all done to support the C function call below which sets */
/* up the htab. This is done because we have relocated the */
/* kernel but are still running in real mode. */
LOADADDR(r3,init_thread_union)
sub r3,r3,r26
/* set up a stack pointer (physical address) */
addi r1,r3,THREAD_SIZE
li r0,0
stdu r0,-STACK_FRAME_OVERHEAD(r1)
/* set up the TOC (physical address) */
LOADADDR(r2,__toc_start)
addi r2,r2,0x4000
addi r2,r2,0x4000
sub r2,r2,r26
LOADADDR(r3,cpu_specs)
sub r3,r3,r26
LOADADDR(r4,cur_cpu_spec)
sub r4,r4,r26
mr r5,r26
bl .identify_cpu
/* Save some low level config HIDs of CPU0 to be copied to
* other CPUs later on, or used for suspend/resume
*/
bl .__save_cpu_setup
sync
/* Setup a valid physical PACA pointer in SPRG3 for early_setup
* note that boot_cpuid can always be 0 nowadays since there is
* nowhere it can be initialized differently before we reach this
* code
*/
LOADADDR(r27, boot_cpuid)
sub r27,r27,r26
lwz r27,0(r27)
LOADADDR(r24, paca) /* Get base vaddr of paca array */
mulli r13,r27,PACA_SIZE /* Calculate vaddr of right paca */
add r13,r13,r24 /* for this processor. */
sub r13,r13,r26 /* convert to physical addr */
mtspr SPRG3,r13 /* PPPBBB: Temp... -Peter */
/* Do very early kernel initializations, including initial hash table,
* stab and slb setup before we turn on relocation. */
/* Restore parameters passed from prom_init/kexec */
mr r3,r31
bl .early_setup
/* set the ASR */
ld r3,PACASTABREAL(r13)
ori r4,r3,1 /* turn on valid bit */
ld r3,systemcfg@got(r2) /* r3 = ptr to systemcfg */
ld r3,0(r3)
lwz r3,PLATFORM(r3) /* r3 = platform flags */
andi. r3,r3,PLATFORM_LPAR /* Test if bit 0 is set (LPAR bit) */
bne 98f
mfspr r3,PVR
srwi r3,r3,16
cmpwi r3,0x37 /* SStar */
beq 97f
cmpwi r3,0x36 /* IStar */
beq 97f
cmpwi r3,0x34 /* Pulsar */
bne 98f
97: li r3,H_SET_ASR /* hcall = H_SET_ASR */
HVSC /* Invoking hcall */
b 99f
98: /* !(rpa hypervisor) || !(star) */
mtasr r4 /* set the stab location */
99:
/* Set SDR1 (hash table pointer) */
ld r3,systemcfg@got(r2) /* r3 = ptr to systemcfg */
ld r3,0(r3)
lwz r3,PLATFORM(r3) /* r3 = platform flags */
/* Test if bit 0 is set (LPAR bit) */
andi. r3,r3,PLATFORM_LPAR
bne 98f
LOADADDR(r6,_SDR1) /* Only if NOT LPAR */
sub r6,r6,r26
ld r6,0(r6) /* get the value of _SDR1 */
mtspr SDR1,r6 /* set the htab location */
98:
LOADADDR(r3,.start_here_common)
SET_REG_TO_CONST(r4, MSR_KERNEL)
mtspr SRR0,r3
mtspr SRR1,r4
rfid
b . /* prevent speculative execution */
#endif /* CONFIG_PPC_MULTIPLATFORM */
/* This is where all platforms converge execution */
_STATIC(start_here_common)
/* relocation is on at this point */
/* The following code sets up the SP and TOC now that we are */
/* running with translation enabled. */
LOADADDR(r3,init_thread_union)
/* set up the stack */
addi r1,r3,THREAD_SIZE
li r0,0
stdu r0,-STACK_FRAME_OVERHEAD(r1)
/* Apply the CPUs-specific fixups (nop out sections not relevant
* to this CPU
*/
li r3,0
bl .do_cpu_ftr_fixups
LOADADDR(r26, boot_cpuid)
lwz r26,0(r26)
LOADADDR(r24, paca) /* Get base vaddr of paca array */
mulli r13,r26,PACA_SIZE /* Calculate vaddr of right paca */
add r13,r13,r24 /* for this processor. */
mtspr SPRG3,r13
/* ptr to current */
LOADADDR(r4,init_task)
std r4,PACACURRENT(r13)
/* Load the TOC */
ld r2,PACATOC(r13)
std r1,PACAKSAVE(r13)
bl .setup_system
/* Load up the kernel context */
5:
#ifdef DO_SOFT_DISABLE
li r5,0
stb r5,PACAPROCENABLED(r13) /* Soft Disabled */
mfmsr r5
ori r5,r5,MSR_EE /* Hard Enabled */
mtmsrd r5
#endif
bl .start_kernel
_GLOBAL(hmt_init)
#ifdef CONFIG_HMT
LOADADDR(r5, hmt_thread_data)
mfspr r7,PVR
srwi r7,r7,16
cmpwi r7,0x34 /* Pulsar */
beq 90f
cmpwi r7,0x36 /* Icestar */
beq 91f
cmpwi r7,0x37 /* SStar */
beq 91f
b 101f
90: mfspr r6,PIR
andi. r6,r6,0x1f
b 92f
91: mfspr r6,PIR
andi. r6,r6,0x3ff
92: sldi r4,r24,3
stwx r6,r5,r4
bl .hmt_start_secondary
b 101f
__hmt_secondary_hold:
LOADADDR(r5, hmt_thread_data)
clrldi r5,r5,4
li r7,0
mfspr r6,PIR
mfspr r8,PVR
srwi r8,r8,16
cmpwi r8,0x34
bne 93f
andi. r6,r6,0x1f
b 103f
93: andi. r6,r6,0x3f
103: lwzx r8,r5,r7
cmpw r8,r6
beq 104f
addi r7,r7,8
b 103b
104: addi r7,r7,4
lwzx r9,r5,r7
mr r24,r9
101:
#endif
mr r3,r24
b .pSeries_secondary_smp_init
#ifdef CONFIG_HMT
_GLOBAL(hmt_start_secondary)
LOADADDR(r4,__hmt_secondary_hold)
clrldi r4,r4,4
mtspr NIADORM, r4
mfspr r4, MSRDORM
li r5, -65
and r4, r4, r5
mtspr MSRDORM, r4
lis r4,0xffef
ori r4,r4,0x7403
mtspr TSC, r4
li r4,0x1f4
mtspr TST, r4
mfspr r4, HID0
ori r4, r4, 0x1
mtspr HID0, r4
mfspr r4, SPRN_CTRLF
oris r4, r4, 0x40
mtspr SPRN_CTRLT, r4
blr
#endif
#if defined(CONFIG_KEXEC) || (defined(CONFIG_SMP) && !defined(CONFIG_PPC_ISERIES))
_GLOBAL(smp_release_cpus)
/* All secondary cpus are spinning on a common
* spinloop, release them all now so they can start
* to spin on their individual paca spinloops.
* For non SMP kernels, the secondary cpus never
* get out of the common spinloop.
*/
li r3,1
LOADADDR(r5,__secondary_hold_spinloop)
std r3,0(r5)
sync
blr
#endif /* CONFIG_SMP && !CONFIG_PPC_ISERIES */
/*
* We put a few things here that have to be page-aligned.
* This stuff goes at the beginning of the bss, which is page-aligned.
*/
.section ".bss"
.align 12
.globl empty_zero_page
empty_zero_page:
.space PAGE_SIZE
.globl swapper_pg_dir
swapper_pg_dir:
.space PAGE_SIZE
/*
* This space gets a copy of optional info passed to us by the bootstrap
* Used to pass parameters into the kernel like root=/dev/sda1, etc.
*/
.globl cmd_line
cmd_line:
.space COMMAND_LINE_SIZE