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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [arch/] [or32/] [kernel/] [head.S] - Rev 1275
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/*
* linux/arch/or32/kernel/head.S
*
* or32 version
* author(s): Matjaz Breskvar (phoenix@opencores.org)
*
* changes:
* 18. 11. 2003: Matjaz Breskvar (phoenix@opencores.org)
* initial port to or32 architecture
* 06. 12. 2003: Matjaz Breskvar (phoenix@opencores.org)
* major changes in handling exceptions
* physical addresses used only by code in head.S
* cleand exception handlers and moved them to entry.S
*/
#include <linux/config.h>
#include <linux/threads.h>
#include <linux/errno.h>
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/mmu.h>
#include <asm/pgtable.h>
#include <asm/cache.h>
#include <asm/or32_asm.h>
#include <asm/spr_defs.h>
#include <asm/board.h>
/* some defines to ease or32 assembly programming */
#include "or32_defs.h"
#include "or32_funcs.S"
#define DRAM_END (PAGE_OFFSET+CONFIG_OR32_MEMORY_SIZE)
#if defined(CONFIG_OR32_ICACHE_ENABLED) && defined(CONFIG_OR32_DCACHE_ENABLED)
# define EXCEPTION_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_DCE | SPR_SR_ICE | SPR_SR_SM)
#elif defined(CONFIG_OR32_ICACHE_ENABLED) && !defined(CONFIG_OR32_DCACHE_ENABLED)
# define EXCEPTION_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE | SPR_SR_SM)
#elif defined(CONFIG_OR32_DCACHE_ENABLED) && !defined(CONFIG_OR32_ICACHE_ENABLED)
# define EXCEPTION_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_DCE | SPR_SR_SM)
#else
# define EXCEPTION_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_SM)
#endif
#undef CONFIG_DMMU_WORKS
#define CONFIG_DMMU_WORKS 1
#undef CONFIG_IMMU_WORKS
#define CONFIG_IMMU_WORKS 1
#undef CONFIG_OR32_EXCEPTION_REGENERATE
//#define CONFIG_OR32_EXCEPTION_REGENERATE 1
#undef CONFIG_OR32_EXCEPTION_DEBUG
//#define CONFIG_OR32_EXCEPTION_DEBUG 1
#undef DEBUG_TLB_EXCEPTIONS
//#define DEBUG_TLB_EXCEPTIONS 1
/* ============================================[ tmp store locations ]=== */
/*
* workaround for passing next open ethernet tx buffer descriptor number
* when used prior linux. for details look into drivers/net/open_eth.[ch]
*/
#define INIT_OETH_TX_NEXT 0x0
/*
* inital configuration
*/
#define INIT_IC_ADDR 0x4
#define INIT_DC_ADDR 0x8
#define SF_DISABLED(reg,ADDR) l.lwz reg,ADDR(r0) ;\
l.sfeqi reg,0x0
#ifdef CONFIG_OR32_ICACHE_ENABLED
# define INIT_CONFIG_ICACHE(reg) l.ori reg,r0,1 ;\
l.sw INIT_IC_ADDR(r0),reg
#else
# define INIT_CONFIG_ICACHE(reg) l.ori reg,r0,0 ;\
l.sw INIT_IC_ADDR(r0),reg
#endif
#ifdef CONFIG_OR32_DCACHE_ENABLED
# define INIT_CONFIG_DCACHE(reg) l.ori reg,r0,1 ;\
l.sw INIT_DC_ADDR(r0),reg
#else
# define INIT_CONFIG_DCACHE(reg) l.ori reg,r0,0 ;\
l.sw INIT_DC_ADDR(r0),reg
#endif
/*
* emergency_print temporary stores
*/
#define EMERGENCY_PRINT_STORE_GPR4 l.sw 0x20(r0),r4
#define EMERGENCY_PRINT_LOAD_GPR4 l.lwz r4,0x20(r0)
#define EMERGENCY_PRINT_STORE_GPR5 l.sw 0x24(r0),r5
#define EMERGENCY_PRINT_LOAD_GPR5 l.lwz r5,0x24(r0)
#define EMERGENCY_PRINT_STORE_GPR6 l.sw 0x28(r0),r6
#define EMERGENCY_PRINT_LOAD_GPR6 l.lwz r6,0x28(r0)
#define EMERGENCY_PRINT_STORE_GPR7 l.sw 0x2c(r0),r7
#define EMERGENCY_PRINT_LOAD_GPR7 l.lwz r7,0x2c(r0)
#define EMERGENCY_PRINT_STORE_GPR8 l.sw 0x30(r0),r8
#define EMERGENCY_PRINT_LOAD_GPR8 l.lwz r8,0x30(r0)
#define EMERGENCY_PRINT_STORE_GPR9 l.sw 0x34(r0),r9
#define EMERGENCY_PRINT_LOAD_GPR9 l.lwz r9,0x34(r0)
/*
* EXCEPTION_DEBUG temporary stores
*/
#define EXCEPTION_DEBUG_STORE_GPR3 l.sw 0x40(r0),r3
#define EXCEPTION_DEBUG_LOAD_GPR3 l.lwz r3,0x40(r0)
#define EXCEPTION_DEBUG_STORE_GPR4 l.sw 0x44(r0),r4
#define EXCEPTION_DEBUG_LOAD_GPR4 l.lwz r4,0x44(r0)
#define EXCEPTION_DEBUG_STORE_GPR9 l.sw 0x48(r0),r9
#define EXCEPTION_DEBUG_LOAD_GPR9 l.lwz r9,0x48(r0)
#define EXCEPTION_DEBUG_STORE_F_GPR9 l.sw 0x4c(r0),r9
#define EXCEPTION_DEBUG_LOAD_F_GPR9 l.lwz r9,0x4c(r0)
/*
* EXCEPTION_REGENERATE temporary stores
*/
#define E_REGEN_STORE_STATUS(reg) l.sw 0x50(r0),reg
#define E_REGEN_LOAD_STATUS(reg) l.lwz reg,0x50(r0)
#define E_REGEN_STORE_GPR3 l.sw 0x54(r0),r3
#define E_REGEN_LOAD_GPR3 l.lwz r3,0x54(r0)
#define E_REGEN_STORE_GPR4 l.sw 0x58(r0),r4
#define E_REGEN_LOAD_GPR4 l.lwz r4,0x58(r0)
#define E_REGEN_STORE_GPR5 l.sw 0x5c(r0),r5
#define E_REGEN_LOAD_GPR5 l.lwz r5,0x5c(r0)
#define E_REGEN_STORE_GPR6 l.sw 0x60(r0),r6
#define E_REGEN_LOAD_GPR6 l.lwz r6,0x60(r0)
#define E_REGEN_STORE_GPR9 l.sw 0x14(r0),r9
#define E_REGEN_LOAD_GPR9 l.lwz r9,0x14(r0)
/*
* TLB miss handlers temorary stores
*/
#define EXCEPTION_STORE_GPR9 l.sw 0x10(r0),r9
#define EXCEPTION_LOAD_GPR9 l.lwz r9,0x10(r0)
#define EXCEPTION_STORE_GPR2 l.sw 0x64(r0),r2
#define EXCEPTION_LOAD_GPR2 l.lwz r2,0x64(r0)
#define EXCEPTION_STORE_GPR3 l.sw 0x68(r0),r3
#define EXCEPTION_LOAD_GPR3 l.lwz r3,0x68(r0)
#define EXCEPTION_STORE_GPR4 l.sw 0x6c(r0),r4
#define EXCEPTION_LOAD_GPR4 l.lwz r4,0x6c(r0)
#define EXCEPTION_STORE_GPR5 l.sw 0x70(r0),r5
#define EXCEPTION_LOAD_GPR5 l.lwz r5,0x70(r0)
#define EXCEPTION_STORE_GPR6 l.sw 0x74(r0),r6
#define EXCEPTION_LOAD_GPR6 l.lwz r6,0x74(r0)
/*
* EXCEPTION_HANDLE temporary stores
*/
#define EXCEPTION_T_STORE_GPR31 l.sw 0x78(r0),r31
#define EXCEPTION_T_LOAD_GPR31(reg) l.lwz reg,0x78(r0)
#define EXCEPTION_T_STORE_GPR2 l.sw 0x7c(r0),r2
#define EXCEPTION_T_LOAD_GPR2(reg) l.lwz reg,0x7c(r0)
#define EXCEPTION_T_STORE_SP l.sw 0x80(r0),r1
#define EXCEPTION_T_LOAD_SP(reg) l.lwz reg,0x80(r0)
/*
* UNHANDLED_EXCEPTION temporary stores
*/
#define UNH_EXCEPTION_T_STORE_GPR31 l.sw 0x84(r0),r31
#define UNH_EXCEPTION_T_LOAD_GPR31(reg) l.lwz reg,0x84(r0)
#define UNH_EXCEPTION_T_STORE_GPR2 l.sw 0x88(r0),r2
#define UNH_EXCEPTION_T_LOAD_GPR2(reg) l.lwz reg,0x88(r0)
#define UNH_EXCEPTION_T_STORE_SP l.sw 0x8c(r0),r1
#define UNH_EXCEPTION_T_LOAD_SP(reg) l.lwz reg,0x8c(r0)
/* =========================================================[ macros ]=== */
#define GET_CURRENT(reg,t1) \
LOAD_SYMBOL_2_GPR(reg,_current_set) ;\
tophys (t1,reg) ;\
l.lwz reg,0(t1)
#define GET_CURRENT_PGD(reg,t1) \
LOAD_SYMBOL_2_GPR(reg,_current_pgd) ;\
tophys (t1,reg) ;\
l.lwz reg,0(t1)
#if defined(CONFIG_OR32_EXCEPTION_DEBUG) && defined(CONFIG_OR32_EXCEPTION_REGENERATE)
# define EXCEPTION_DEBUG \
EXCEPTION_DEBUG_STORE_GPR4 ;\
EXCEPTION_DEBUG_STORE_F_GPR9 ;\
l.jal _exception_debug ;\
l.mfspr r4,r0,SPR_PC ;\
EXCEPTION_DEBUG_LOAD_GPR4 ;\
EXCEPTION_DEBUG_LOAD_F_GPR9
# define EXCEPTION_DEBUG_VALUE(value) \
EXCEPTION_DEBUG_STORE_GPR4 ;\
EXCEPTION_DEBUG_STORE_F_GPR9 ;\
l.jal _exception_debug ;\
l.addi r4,r0,value ;\
EXCEPTION_DEBUG_LOAD_GPR4 ;\
EXCEPTION_DEBUG_LOAD_F_GPR9
# define EXCEPTION_DEBUG_ER \
EXCEPTION_DEBUG_STORE_GPR4 ;\
EXCEPTION_DEBUG_STORE_F_GPR9 ;\
l.jal _exception_debug ;\
l.mfspr r4,r0,SPR_PC ;\
l.jal _exception_regenerate ;\
l.nop ;\
EXCEPTION_DEBUG_LOAD_GPR4 ;\
EXCEPTION_DEBUG_LOAD_F_GPR9
# define EXCEPTION_DEBUG_VALUE_ER(value) \
EXCEPTION_DEBUG_STORE_GPR4 ;\
EXCEPTION_DEBUG_STORE_F_GPR9 ;\
l.jal _exception_debug ;\
l.addi r4,r0,value ;\
l.jal _exception_regenerate ;\
l.nop ;\
EXCEPTION_DEBUG_LOAD_GPR4 ;\
EXCEPTION_DEBUG_LOAD_F_GPR9
#elif !defined(CONFIG_OR32_EXCEPTION_DEBUG) && defined(CONFIG_OR32_EXCEPTION_REGENERATE)
# define EXCEPTION_DEBUG
# define EXCEPTION_DEBUG_VALUE(value)
# define EXCEPTION_DEBUG_ER \
EXCEPTION_DEBUG_STORE_GPR4 ;\
EXCEPTION_DEBUG_STORE_F_GPR9 ;\
l.jal _exception_regenerate ;\
l.nop ;\
EXCEPTION_DEBUG_LOAD_GPR4 ;\
EXCEPTION_DEBUG_LOAD_F_GPR9
# define EXCEPTION_DEBUG_VALUE_ER(value) \
EXCEPTION_DEBUG_STORE_GPR4 ;\
EXCEPTION_DEBUG_STORE_F_GPR9 ;\
l.jal _exception_regenerate ;\
l.nop ;\
EXCEPTION_DEBUG_LOAD_GPR4 ;\
EXCEPTION_DEBUG_LOAD_F_GPR9
#elif defined(CONFIG_OR32_EXCEPTION_DEBUG) && !defined(CONFIG_OR32_EXCEPTION_REGENERATE)
# define EXCEPTION_DEBUG \
EXCEPTION_DEBUG_STORE_GPR4 ;\
EXCEPTION_DEBUG_STORE_F_GPR9 ;\
l.jal _exception_debug ;\
l.mfspr r4,r0,SPR_PC ;\
EXCEPTION_DEBUG_LOAD_GPR4 ;\
EXCEPTION_DEBUG_LOAD_F_GPR9
# define EXCEPTION_DEBUG_VALUE(value) \
EXCEPTION_DEBUG_STORE_GPR4 ;\
EXCEPTION_DEBUG_STORE_F_GPR9 ;\
l.jal _exception_debug ;\
l.addi r4,r0,value ;\
EXCEPTION_DEBUG_LOAD_GPR4 ;\
EXCEPTION_DEBUG_LOAD_F_GPR9
# define EXCEPTION_DEBUG_ER \
EXCEPTION_DEBUG
# define EXCEPTION_DEBUG_VALUE_ER(value) \
EXCEPTION_DEBUG_VALUE(value)
#else
# define EXCEPTION_DEBUG
# define EXCEPTION_DEBUG_VALUE(value)
# define EXCEPTION_DEBUG_ER
# define EXCEPTION_DEBUG_VALUE_ER(value)
#endif
# define EXCEPTION_DEBUG_VALUE_ER_ENABLED(value) \
EXCEPTION_DEBUG_STORE_GPR4 ;\
EXCEPTION_DEBUG_STORE_F_GPR9 ;\
l.jal _exception_debug ;\
l.addi r4,r0,value ;\
l.jal _exception_regenerate ;\
l.nop ;\
EXCEPTION_DEBUG_LOAD_GPR4 ;\
EXCEPTION_DEBUG_LOAD_F_GPR9
# define EXCEPTION_DEBUG_VALUE_ENABLED(value) \
EXCEPTION_DEBUG_STORE_GPR4 ;\
EXCEPTION_DEBUG_STORE_F_GPR9 ;\
l.jal _exception_debug ;\
l.addi r4,r0,value ;\
EXCEPTION_DEBUG_LOAD_GPR4 ;\
EXCEPTION_DEBUG_LOAD_F_GPR9
#ifdef DEBUG_TLB_EXCEPTIONS
# define DEBUG_TLB_PROBE(value) \
EXCEPTION_DEBUG_VALUE_ENABLED(value)
#else
# define DEBUG_TLB_PROBE(value)
#endif
/*
* DSCR: this is a common hook for handling exceptions. it will save
* the needed registers, set up stack and pointer to current
* then jump to the handler while enabling MMU
*
* PRMS: handler - a function to jump to. it has to save the
* remaining registers to kernel stack, call
* appropriate arch-independant exception handler
* and finaly jump to ret_from_except
*
* PREQ: unchanged state from the time exception happened
*
* POST: SAVED the following registers original value
* to the new created exception frame pointed to by r1
*
* r1 - ksp pointing to the new (exception) frame
* r2 - current pointing to current process struct
* r4 - EEAR exception EA
* r12 - syscall 0, since we didn't come from syscall
* r13 - temp it actually contains new SR, not needed anymore
* r31 - handler address of the handler we'll jump to
*
* handler has to save remaining registers to the exception
* ksp frame *before* tainting them!
*
* NOTE: this function is not reentrant per se. reentrancy is guaranteed
* by processor disabling all exceptions/interrupts when exception
* accours.
*
* OPTM: no need to make it so wasteful to extract ksp when in user mode
*/
#define EXCEPTION_HANDLE(handler) \
EXCEPTION_DEBUG ;\
EXCEPTION_T_STORE_GPR31 ;\
EXCEPTION_T_STORE_GPR2 ;\
EXCEPTION_T_STORE_SP ;\
l.mfspr r31,r0,SPR_ESR_BASE ;\
l.andi r31,r31,SPR_SR_SM ;\
l.sfeqi r31,0 ;\
l.bnf 2f /* kernel_mode */ ;\
l.nop ;\
1: /* user_mode: */ ;\
LOAD_SYMBOL_2_GPR(r1,_current_set) ;\
tophys (r31,r1) ;\
/* r2: current */ ;\
l.lwz r2,0(r31) ;\
tophys (r31,r2) ;\
l.lwz r1,(THREAD+THREAD_KSP)(r31) ;\
/* fall through */ ;\
2: /* kernel_mode: */ ;\
/* create new stack frame, save only needed gprs */ ;\
/* r1: KSP, r2: current, r4: EEAR, r31: __pa(KSP) */ ;\
/* r12: temp, syscall indicator, r13 temp */ ;\
l.addi r1,r1,-(INT_FRAME_SIZE) ;\
/* r1 is KSP, r31 is __pa(KSP) */ ;\
tophys (r31,r1) ;\
l.sw GPR12(r31),r12 ;\
l.mfspr r12,r0,SPR_EPCR_BASE ;\
l.sw PC(r31),r12 ;\
l.mfspr r12,r0,SPR_ESR_BASE ;\
l.sw SR(r31),r12 ;\
/* save r31 */ ;\
EXCEPTION_T_LOAD_GPR31(r12) ;\
l.sw GPR31(r31),r12 ;\
/* save r2 as was prior to exception */ ;\
EXCEPTION_T_LOAD_GPR2(r12) ;\
l.sw GPR2(r31),r12 ;\
/* save SP as was prior to exception */ ;\
EXCEPTION_T_LOAD_SP(r12) ;\
l.sw SP(r31),r12 ;\
l.sw GPR13(r31),r13 ;\
/* save exception r4, set r4 = EA */ ;\
l.sw GPR4(r31),r4 ;\
l.mfspr r4,r0,SPR_EEAR_BASE ;\
/* r12 == 1 if we come from syscall */ ;\
CLEAR_GPR(r12) ;\
/* ----- turn on MMU ----- */ ;\
l.addi r31,r0,(EXCEPTION_SR) ;\
l.mtspr r0,r31,SPR_ESR_BASE ;\
/* r31: EA address of handler */ ;\
LOAD_SYMBOL_2_GPR(r31,handler) ;\
l.mtspr r0,r31,SPR_EPCR_BASE ;\
l.rfe
/*
* this doesn't work
*
*
* #ifdef CONFIG_JUMP_UPON_UNHANDLED_EXCEPTION
* #define UNHANDLED_EXCEPTION(handler) \
* l.ori r3,r0,0x1 ;\
* l.mtspr r0,r3,SPR_SR ;\
* l.movhi r3,hi(0xf0000100) ;\
* l.ori r3,r3,lo(0xf0000100) ;\
* l.jr r3 ;\
* l.nop 1
*
* #endif
*/
/* DSCR: this is the same as EXCEPTION_HANDLE(), we are just
* a bit more carefull (if we have a SP or current pointer
* corruption) and set them up from 'current_set'
*
*/
#define UNHANDLED_EXCEPTION(handler) \
EXCEPTION_DEBUG ;\
EXCEPTION_T_STORE_GPR31 ;\
EXCEPTION_T_STORE_GPR2 ;\
EXCEPTION_T_STORE_SP ;\
/* temporary store r3, r9 into r1, r2 */ ;\
l.addi r1,r3,0x0 ;\
l.addi r2,r9,0x0 ;\
/* the string referenced by r3 must be low enough */ ;\
l.jal _emergency_print ;\
l.ori r3,r0,lo(_string_unhandled_exception) ;\
l.mfspr r3,r0,SPR_PC ;\
l.jal _emergency_print_nr ;\
l.andi r3,r3,0x1f00 ;\
/* the string referenced by r3 must be low enough */ ;\
l.jal _emergency_print ;\
l.ori r3,r0,lo(_string_epc_prefix) ;\
l.jal _emergency_print_nr ;\
l.mfspr r3,r0,SPR_EPCR_BASE ;\
l.jal _emergency_print ;\
l.ori r3,r0,lo(_string_nl) ;\
/* end of printing */ ;\
l.addi r3,r1,0x0 ;\
l.addi r9,r2,0x0 ;\
/* extract current, ksp from current_set */ ;\
LOAD_SYMBOL_2_GPR(r1,_unhandled_stack_top) ;\
LOAD_SYMBOL_2_GPR(r2,_init_task_union) ;\
/* create new stack frame, save only needed gprs */ ;\
/* r1: KSP, r2: current, r31: __pa(KSP) */ ;\
/* r12: temp, syscall indicator, r13 temp */ ;\
l.addi r1,r1,-(INT_FRAME_SIZE) ;\
/* r1 is KSP, r31 is __pa(KSP) */ ;\
tophys (r31,r1) ;\
l.sw GPR12(r31),r12 ;\
l.mfspr r12,r0,SPR_EPCR_BASE ;\
l.sw PC(r31),r12 ;\
l.mfspr r12,r0,SPR_ESR_BASE ;\
l.sw SR(r31),r12 ;\
/* save r31 */ ;\
EXCEPTION_T_LOAD_GPR31(r12) ;\
l.sw GPR31(r31),r12 ;\
/* save r2 as was prior to exception */ ;\
EXCEPTION_T_LOAD_GPR2(r12) ;\
l.sw GPR2(r31),r12 ;\
/* save SP as was prior to exception */ ;\
EXCEPTION_T_LOAD_SP(r12) ;\
l.sw SP(r31),r12 ;\
l.sw GPR13(r31),r13 ;\
/* --> */ ;\
/* save exception r4, set r4 = EA */ ;\
l.sw GPR4(r31),r4 ;\
l.mfspr r4,r0,SPR_EEAR_BASE ;\
/* r12 == 1 if we come from syscall */ ;\
CLEAR_GPR(r12) ;\
/* ----- play a MMU trick ----- */ ;\
l.addi r31,r0,(EXCEPTION_SR) ;\
l.mtspr r0,r31,SPR_ESR_BASE ;\
/* r31: EA address of handler */ ;\
LOAD_SYMBOL_2_GPR(r31,handler) ;\
l.mtspr r0,r31,SPR_EPCR_BASE ;\
l.rfe
/* =====================================================[ exceptions] === */
/* ---[ 0x100: RESET exception ]----------------------------------------- */
.org 0x100
l.ori r3,r0,0x1
l.mtspr r0,r3,SPR_SR
#ifdef CONFIG_OR32_FLASH_BOOT
LOAD_SYMBOL_2_GPR(r3,0xf0000118) // jumps to the 'reset_start'
l.jr r3
l.nop
reset_start:
l.jal _mc_init
l.nop
l.jal _early_uart_init
l.nop
LOAD_SYMBOL_2_GPR(r4,_string_copying_linux)
l.movhi r3,hi(0x30000000)
l.add r3,r3,r4
l.jal _emergency_print
l.nop
/*
* copy linux kernel image from flash to sdram
*/
LOAD_SYMBOL_2_GPR(r3,0xf0000000) // source
LOAD_SYMBOL_2_GPR(r4,0x0) // destination
LOAD_SYMBOL_2_GPR(r6,__end) // last destination
tophys (r5,r6) // last destination
/*
* copy %r3 to %r4 until %r4 == %r5
*/
2:
l.sfgeu r4,r5
l.bf 1f
l.nop
l.lwz r8,0(r3)
l.sw 0(r4),r8
l.addi r3,r3,4
l.j 2b
l.addi r4,r4,4
1:
#else
#if 0
l.jal _mc_init
l.nop
l.jal _early_uart_init
l.nop
#endif
#endif /* CONFIG_OR32_FLASH_BOOT */
#if 0
LOAD_SYMBOL_2_GPR(r4,_string_ok_booting)
tophys (r3,r4)
l.jal _emergency_print
l.nop
#endif
LOAD_SYMBOL_2_GPR(r4, _start)
tophys (r3,r4) // physical address
l.jr r3
l.nop
/* ---[ 0x200: BUS exception ]------------------------------------------- */
.org 0x200
_dispatch_bus_fault:
UNHANDLED_EXCEPTION(_vector_0x200)
/* ---[ 0x300: Data Page Fault exception ]------------------------------- */
.org 0x300
_dispatch_do_dpage_fault:
// totaly disable timer interrupt
// l.mtspr r0,r0,SPR_TTMR
// DEBUG_TLB_PROBE(0x300)
// EXCEPTION_DEBUG_VALUE_ER_ENABLED(0x300)
EXCEPTION_HANDLE(_data_page_fault_handler)
/* ---[ 0x400: Insn Page Fault exception ]------------------------------- */
.org 0x400
_dispatch_do_ipage_fault:
// totaly disable timer interrupt
// l.mtspr r0,r0,SPR_TTMR
// DEBUG_TLB_PROBE(0x400)
// EXCEPTION_DEBUG_VALUE_ER_ENABLED(0x400)
EXCEPTION_HANDLE(_insn_page_fault_handler)
/* ---[ 0x500: Timer exception ]----------------------------------------- */
.org 0x500
EXCEPTION_HANDLE(_timer_handler)
/* ---[ 0x600: Aligment exception ]-------------------------------------- */
.org 0x600
UNHANDLED_EXCEPTION(_vector_0x600)
// EXCEPTION_HANDLE(_aligment_handler)
/* ---[ 0x700: Illegal insn exception ]---------------------------------- */
.org 0x700
UNHANDLED_EXCEPTION(_vector_0x700)
/* ---[ 0x800: External interrupt exception ]---------------------------- */
.org 0x800
EXCEPTION_HANDLE(_external_irq_handler)
/* ---[ 0x900: DTLB miss exception ]------------------------------------- */
.org 0x900
l.j boot_dtlb_miss_handler
l.nop
/* ---[ 0xa00: ITLB miss exception ]------------------------------------- */
.org 0xa00
l.j boot_itlb_miss_handler
l.nop
/* ---[ 0xb00: Range exception ]----------------------------------------- */
.org 0xb00
UNHANDLED_EXCEPTION(_vector_0xb00)
/* ---[ 0xc00: Syscall exception ]--------------------------------------- */
.org 0xc00
EXCEPTION_HANDLE(_sys_call_handler)
/* ---[ 0xd00: Trap exception ]------------------------------------------ */
.org 0xd00
UNHANDLED_EXCEPTION(_vector_0xd00)
/* ---[ 0xe00: Trap exception ]------------------------------------------ */
.org 0xe00
UNHANDLED_EXCEPTION(_vector_0xe00)
/* ---[ 0xf00: Reserved exception ]-------------------------------------- */
.org 0xf00
UNHANDLED_EXCEPTION(_vector_0xf00)
/* ---[ 0x1000: Reserved exception ]------------------------------------- */
.org 0x1000
UNHANDLED_EXCEPTION(_vector_0x1000)
/* ---[ 0x1100: Reserved exception ]------------------------------------- */
.org 0x1100
UNHANDLED_EXCEPTION(_vector_0x1100)
/* ---[ 0x1200: Reserved exception ]------------------------------------- */
.org 0x1200
UNHANDLED_EXCEPTION(_vector_0x1200)
/* ---[ 0x1300: Reserved exception ]------------------------------------- */
.org 0x1300
UNHANDLED_EXCEPTION(_vector_0x1300)
/* ---[ 0x1400: Reserved exception ]------------------------------------- */
.org 0x1400
UNHANDLED_EXCEPTION(_vector_0x1400)
/* ---[ 0x1500: Reserved exception ]------------------------------------- */
.org 0x1500
UNHANDLED_EXCEPTION(_vector_0x1500)
/* ---[ 0x1600: Reserved exception ]------------------------------------- */
.org 0x1600
UNHANDLED_EXCEPTION(_vector_0x1600)
/* ---[ 0x1700: Reserved exception ]------------------------------------- */
.org 0x1700
UNHANDLED_EXCEPTION(_vector_0x1700)
/* ---[ 0x1800: Reserved exception ]------------------------------------- */
.org 0x1800
UNHANDLED_EXCEPTION(_vector_0x1800)
/* ---[ 0x1900: Reserved exception ]------------------------------------- */
.org 0x1900
UNHANDLED_EXCEPTION(_vector_0x1900)
/* ---[ 0x1a00: Reserved exception ]------------------------------------- */
.org 0x1a00
UNHANDLED_EXCEPTION(_vector_0x1a00)
/* ---[ 0x1b00: Reserved exception ]------------------------------------- */
.org 0x1b00
UNHANDLED_EXCEPTION(_vector_0x1b00)
/* ---[ 0x1c00: Reserved exception ]------------------------------------- */
.org 0x1c00
UNHANDLED_EXCEPTION(_vector_0x1c00)
/* ---[ 0x1d00: Reserved exception ]------------------------------------- */
.org 0x1d00
UNHANDLED_EXCEPTION(_vector_0x1d00)
/* ---[ 0x1e00: Reserved exception ]------------------------------------- */
.org 0x1e00
UNHANDLED_EXCEPTION(_vector_0x1e00)
/* ---[ 0x1f00: Reserved exception ]------------------------------------- */
.org 0x1f00
UNHANDLED_EXCEPTION(_vector_0x1f00)
.org 0x2000
/* ===================================================[ kernel start ]=== */
.text
.global _stext
_stext:
.global _start
_start:
/*
* ensure a deterministic start
*/
l.ori r3,r0,0x1
l.mtspr r0,r3,SPR_SR
CLEAR_GPR(r1)
CLEAR_GPR(r2)
CLEAR_GPR(r3)
CLEAR_GPR(r4)
CLEAR_GPR(r5)
CLEAR_GPR(r6)
CLEAR_GPR(r7)
CLEAR_GPR(r8)
CLEAR_GPR(r9)
CLEAR_GPR(r10)
CLEAR_GPR(r11)
CLEAR_GPR(r12)
CLEAR_GPR(r13)
CLEAR_GPR(r14)
CLEAR_GPR(r15)
CLEAR_GPR(r16)
CLEAR_GPR(r17)
CLEAR_GPR(r18)
CLEAR_GPR(r19)
CLEAR_GPR(r20)
CLEAR_GPR(r21)
CLEAR_GPR(r22)
CLEAR_GPR(r23)
CLEAR_GPR(r24)
CLEAR_GPR(r25)
CLEAR_GPR(r26)
CLEAR_GPR(r27)
CLEAR_GPR(r28)
CLEAR_GPR(r29)
CLEAR_GPR(r30)
CLEAR_GPR(r31)
/*
* set up initial ksp and current
*/
LOAD_SYMBOL_2_GPR(r1,_init_task_union+0x2000) // setup kernel stack
LOAD_SYMBOL_2_GPR(r2,_init_task_union) // setup current
write_config:
INIT_CONFIG_ICACHE(r3)
INIT_CONFIG_DCACHE(r3)
l.ori r4,r0,0x0
E_REGEN_STORE_STATUS(r4) //
/*
* .data contains initialized data,
* .bss contains uninitialized data - clear it up
*/
clear_bss:
LOAD_SYMBOL_2_GPR(r24, ___bss_start)
LOAD_SYMBOL_2_GPR(r26, __end)
tophys(r28,r24)
tophys(r30,r26)
CLEAR_GPR(r24)
CLEAR_GPR(r26)
1:
l.sw (0)(r28),r0
l.sfltu r28,r30
l.bf 1b
l.addi r28,r28,4
enable_ic:
l.jal _ic_enable
l.nop
enable_dc:
l.jal _dc_enable
l.nop
flush_tlb:
/*
* I N V A L I D A T E T L B e n t r i e s
*/
LOAD_SYMBOL_2_GPR(r5,SPR_DTLBMR_BASE(0))
LOAD_SYMBOL_2_GPR(r6,SPR_ITLBMR_BASE(0))
l.addi r7,r0,64
1:
l.mtspr r5,r0,0x0
l.mtspr r6,r0,0x0
l.addi r5,r5,1
l.addi r6,r6,1
l.sfeq r7,r0
l.bnf 1b
l.addi r7,r7,-1
enable_mmu:
/*
* enable dmmu & immu
* SR[5] = 0, SR[6] = 0, 6th and 7th bit of SR set to 0
*/
SR_ENABLE_BITS((SPR_SR_DME | SPR_SR_IME),r28,r30)
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
/*
* clear all GPRS to increase determinism
*/
CLEAR_GPR(r3)
CLEAR_GPR(r4)
CLEAR_GPR(r5)
CLEAR_GPR(r6)
CLEAR_GPR(r7)
CLEAR_GPR(r8)
CLEAR_GPR(r9)
CLEAR_GPR(r10)
CLEAR_GPR(r11)
CLEAR_GPR(r12)
CLEAR_GPR(r13)
CLEAR_GPR(r14)
CLEAR_GPR(r15)
CLEAR_GPR(r16)
CLEAR_GPR(r17)
CLEAR_GPR(r18)
CLEAR_GPR(r19)
CLEAR_GPR(r20)
CLEAR_GPR(r21)
CLEAR_GPR(r22)
CLEAR_GPR(r23)
CLEAR_GPR(r24)
CLEAR_GPR(r25)
CLEAR_GPR(r26)
CLEAR_GPR(r27)
CLEAR_GPR(r28)
CLEAR_GPR(r29)
CLEAR_GPR(r30)
CLEAR_GPR(r31)
jump_start_kernel:
/*
* jump to kernel entry (start_kernel)
*/
LOAD_SYMBOL_2_GPR(r30, _start_kernel)
l.jr r30
l.nop
/* ========================================[ memory controler, cache ]=== */
#if CONFIG_OR32_MC_VERSION==1
ENTRY(_mc_init)
l.movhi r3,hi(MC_BASE_ADD)
l.ori r3,r3,lo(MC_BASE_ADD)
l.addi r4,r3,MC_CSC(0)
l.movhi r5,hi(FLASH_BASE_ADD)
l.srai r5,r5,6
l.ori r5,r5,0x0025
l.sw 0(r4),r5
l.addi r4,r3,MC_TMS(0)
l.movhi r5,hi(FLASH_TMS_VAL)
l.ori r5,r5,lo(FLASH_TMS_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_BA_MASK
l.addi r5,r0,MC_MASK_VAL
l.sw 0(r4),r5
l.addi r4,r3,MC_CSR
l.movhi r5,hi(MC_CSR_VAL)
l.ori r5,r5,lo(MC_CSR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_TMS(1)
l.movhi r5,hi(SDRAM_TMS_VAL)
l.ori r5,r5,lo(SDRAM_TMS_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_CSC(1)
l.movhi r5,hi(SDRAM_BASE_ADD)
l.srai r5,r5,6
l.ori r5,r5,0x0411
l.sw 0(r4),r5
#ifdef FBMEM_BASE_ADD
l.addi r4,r3,MC_CSC(2)
l.movhi r5,hi(FBMEM_BASE_ADD)
l.srai r5,r5,6
l.ori r5,r5,0x0005
l.sw 0(r4),r5
l.addi r4,r3,MC_TMS(2)
l.movhi r5,0xffff
l.ori r5,r5,0xffff
l.sw 0(r4),r5
#endif
l.jr r9
l.nop
#elif CONFIG_OR32_MC_VERSION==2
ENTRY(_mc_init)
l.movhi r3,hi(MC_BASE_ADD)
l.ori r3,r3,lo(MC_BASE_ADD)
l.addi r4,r3,MC_BAR_0
l.movhi r5,hi(FLASH_BAR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_AMR_0
l.movhi r5,hi(FLASH_AMR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_WTR_0
l.movhi r5,hi(FLASH_WTR_VAL)
l.ori r5,r5,lo(FLASH_WTR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_RTR_0
l.movhi r5,hi(FLASH_RTR_VAL)
l.ori r5,r5,lo(FLASH_RTR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_OSR
l.movhi r5,hi(0x40000000)
l.ori r5,r5,lo(0x40000000)
l.sw 0(r4),r5
l.addi r4,r3,MC_BAR_4
l.movhi r5,hi(SDRAM_BAR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_AMR_4
l.movhi r5,hi(SDRAM_AMR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_CCR_4
l.movhi r5,hi(0x00ef0004)
l.ori r5,r5,lo(0x00ef0004)
l.sw 0(r4),r5
l.addi r4,r3,MC_RATR
l.movhi r5,hi(SDRAM_RATR_VAL)
l.ori r5,r5,lo(SDRAM_RATR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_RCDR
l.movhi r5,hi(SDRAM_RCDR_VAL)
l.ori r5,r5,lo(SDRAM_RCDR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_RCTR
l.movhi r5,hi(SDRAM_RCTR_VAL)
l.ori r5,r5,lo(SDRAM_RCTR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_REFCTR
l.movhi r5,hi(SDRAM_REFCTR_VAL)
l.ori r5,r5,lo(SDRAM_REFCTR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_PTR
l.movhi r5,hi(SDRAM_PTR_VAL)
l.ori r5,r5,lo(SDRAM_PTR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_RRDR
l.movhi r5,hi(SDRAM_RRDR_VAL)
l.ori r5,r5,lo(SDRAM_RRDR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_WRTR
l.movhi r5,hi(SDRAM_WRTR_VAL)
l.ori r5,r5,lo(SDRAM_WRTR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_RIR
l.movhi r5,hi(SDRAM_RIR_VAL)
l.ori r5,r5,lo(SDRAM_RIR_VAL)
l.sw 0(r4),r5
l.addi r4,r3,MC_OSR
l.movhi r5,hi(0x5e000000)
l.ori r5,r5,lo(0x5e000000)
l.sw 0(r4),r5
l.addi r4,r3,MC_ORR
l.sw 0(r4),r5
l.addi r4,r3,MC_OSR
l.movhi r5,hi(0x6e000000)
l.ori r5,r5,lo(0x6e000000)
l.sw 0(r4),r5
l.addi r4,r3,MC_ORR
l.sw 0(r4),r5
l.sw 0(r4),r5
l.sw 0(r4),r5
l.sw 0(r4),r5
l.sw 0(r4),r5
l.sw 0(r4),r5
l.sw 0(r4),r5
l.sw 0(r4),r5
l.addi r4,r3,MC_OSR
l.movhi r5,hi(0x7e000023)
l.ori r5,r5,lo(0x7e000023)
l.sw 0(r4),r5
l.addi r4,r3,MC_ORR
l.sw 0(r4),r5
l.addi r4,r3,MC_CCR_4
l.movhi r5,hi(0xc0ee0004)
l.ori r5,r5,lo(0xc0ee0004)
l.sw 0(r4),r5
l.jr r9
l.nop
#else
# error "no memory controler specified"
#endif
#ifdef CONFIG_OR32_CACHE_DEBUG
ENTRY(_ic_enable)
SF_DISABLED(r6,INIT_IC_ADDR)
l.bf 9f
l.nop
EMERGENCY_PRINT_STORE_GPR9
LOAD_SYMBOL_2_GPR(r4,_string_icache_clean)
tophys (r3,r4)
l.jal _emergency_print
l.nop
/* Disable IC */
l.mfspr r6,r0,SPR_SR
l.addi r5,r0,-1
l.xori r5,r5,SPR_SR_ICE
l.and r5,r6,r5
l.mtspr r0,r5,SPR_SR
/* Invalidate IC */
l.addi r6,r0,0
l.addi r5,r0,IC_SIZE
1:
#if 0
LOAD_SYMBOL_2_GPR(r4,_string_ic_invalidate)
tophys (r3,r4)
l.jal _emergency_print
l.nop
l.jal _emergency_print_nr
l.addi r3,r6,0
#endif
l.mtspr r0,r6,SPR_ICBIR
l.sfne r6,r5
l.bf 1b
l.addi r6,r6,IC_LINE
LOAD_SYMBOL_2_GPR(r4,_string_ic_enable)
tophys (r3,r4)
l.jal _emergency_print
l.nop
/* Enable IC */
l.mfspr r6,r0,SPR_SR
l.ori r6,r6,SPR_SR_ICE
l.mtspr r0,r6,SPR_SR
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
EMERGENCY_PRINT_LOAD_GPR9
9:
l.jr r9
l.nop
#else
ENTRY(_ic_enable)
SF_DISABLED(r6,INIT_IC_ADDR)
l.bf 9f
l.nop
/* Disable IC */
l.mfspr r6,r0,SPR_SR
l.addi r5,r0,-1
l.xori r5,r5,SPR_SR_ICE
l.and r5,r6,r5
l.mtspr r0,r5,SPR_SR
/* Invalidate IC */
l.addi r6,r0,0
l.addi r5,r0,IC_SIZE
1:
l.mtspr r0,r6,SPR_ICBIR
l.sfne r6,r5
l.bf 1b
l.addi r6,r6,IC_LINE
/* Enable IC */
l.mfspr r6,r0,SPR_SR
l.ori r6,r6,SPR_SR_ICE
l.mtspr r0,r6,SPR_SR
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
l.nop
9:
l.jr r9
l.nop
#endif
#ifdef CONFIG_OR32_CACHE_DEBUG
ENTRY(_dc_enable)
SF_DISABLED(r6,INIT_DC_ADDR)
l.bf 9f
l.nop
EMERGENCY_PRINT_STORE_GPR9
LOAD_SYMBOL_2_GPR(r4,_string_dcache_clean)
tophys (r3,r4)
l.jal _emergency_print
l.nop
/* Disable DC */
l.mfspr r6,r0,SPR_SR
l.addi r5,r0,-1
l.xori r5,r5,SPR_SR_DCE
l.and r5,r6,r5
l.mtspr r0,r5,SPR_SR
/* Flush DC */
l.addi r6,r0,0
l.addi r5,r0,DC_SIZE
1:
#ifdef CONFIG_OR32_CACHE_DEBUG
LOAD_SYMBOL_2_GPR(r4,_string_dc_invalidate)
tophys (r3,r4)
l.jal _emergency_print
l.nop
l.jal _emergency_print_nr
l.addi r3,r6,0
#endif
l.mtspr r0,r6,SPR_DCBIR
l.sfne r6,r5
l.bf 1b
l.addi r6,r6,DC_LINE
LOAD_SYMBOL_2_GPR(r4,_string_dc_enable)
tophys (r3,r4)
l.jal _emergency_print
l.nop
/* Enable DC */
l.mfspr r6,r0,SPR_SR
l.ori r6,r6,SPR_SR_DCE
l.mtspr r0,r6,SPR_SR
EMERGENCY_PRINT_LOAD_GPR9
9:
l.jr r9
l.nop
#else
ENTRY(_dc_enable)
SF_DISABLED(r6,INIT_DC_ADDR)
l.bf 9f
l.nop
/* Disable DC */
l.mfspr r6,r0,SPR_SR
l.addi r5,r0,-1
l.xori r5,r5,SPR_SR_DCE
l.and r5,r6,r5
l.mtspr r0,r5,SPR_SR
/* Flush DC */
l.addi r6,r0,0
l.addi r5,r0,DC_SIZE
1:
l.mtspr r0,r6,SPR_DCBIR
l.sfne r6,r5
l.bf 1b
l.addi r6,r6,DC_LINE
/* Enable DC */
l.mfspr r6,r0,SPR_SR
l.ori r6,r6,SPR_SR_DCE
l.mtspr r0,r6,SPR_SR
9:
l.jr r9
l.nop
#endif
/* ===============================================[ page table masks ]=== */
#define DTLB_UP_CONVERT_MASK 0x3fe
#define ITLB_UP_CONVERT_MASK 0x3e
/* for SMP we'd have (this is a bit subtle, CC must be always set
* for SMP, but since we have _PAGE_PRESENT bit always defined
* we can just modify the mask)
*/
#define DTLB_SMP_CONVERT_MASK 0x3ff
#define ITLB_SMP_CONVERT_MASK 0x3f
/* ==============================================[ DTLB miss handler ]=== */
.global _dtlb_miss_handler
_dtlb_miss_handler:
EXCEPTION_DEBUG_VALUE_ER(0x900)
EXCEPTION_STORE_GPR2
EXCEPTION_STORE_GPR3
EXCEPTION_STORE_GPR4
EXCEPTION_STORE_GPR5
/*
* get EA of the miss
*/
l.mfspr r2,r0,SPR_EEAR_BASE
/*
* pmd = (pmd_t *)(current_pgd + pgd_index(daddr));
*/
GET_CURRENT_PGD(r3,r5) // r3 is current_pgd, r5 is temp
l.srli r4,r2,0x18 // >> PAGE_SHIFT + (PAGE_SHIFT - 2)
l.slli r4,r4,0x2 // to get address << 2
l.add r5,r4,r3 // r4 is pgd_index(daddr)
/*
* if (pmd_none(*pmd))
* goto pmd_none:
*/
tophys (r4,r5)
l.lwz r3,0x0(r4) // get *pmd value
l.sfne r3,r0
l.bnf d_pmd_none
l.andi r3,r3,0x1fff // ~PAGE_MASK
/*
* if (pmd_bad(*pmd))
* pmd_clear(pmd)
* goto pmd_bad:
*/
// l.sfeq r3,r0 // check *pmd value
// l.bf d_pmd_good
l.addi r3,r0,0xffffe000 // PAGE_MASK
// l.j d_pmd_bad
// l.sw 0x0(r4),r0 // clear pmd
d_pmd_good:
/*
* pte = *pte_offset(pmd, daddr);
*/
l.lwz r4,0x0(r4) // get **pmd value
l.and r4,r4,r3 // & PAGE_MASK
l.srli r5,r2,0xd // >> PAGE_SHIFT, r2 == EEAR
l.andi r3,r5,0x7ff // (1UL << PAGE_SHIFT - 2) - 1
l.slli r3,r3,0x2 // to get address << 2
l.add r3,r3,r4
l.lwz r2,0x0(r3) // this is pte at last
/*
* if (!pte_present(pte))
*/
l.andi r4,r2,0x1
l.sfne r4,r0 // is pte present
l.bnf d_pte_not_present
l.addi r3,r0,0xffffe3fe // PAGE_MASK | DTLB_UP_CONVERT_MASK
/*
* fill DTLB TR register
*/
l.and r4,r2,r3 // apply the mask
l.andi r5,r5,0x3f // calc offset: & (NUM_TLB_ENTRIES-1), NUM_TLB_ENTRIES == 64
l.mtspr r5,r4,SPR_DTLBTR_BASE(0)
/*
* fill DTLB MR register
*/
l.mfspr r2,r0,SPR_EEAR_BASE
l.addi r3,r0,0xffffe000 // PAGE_MASK
l.and r4,r2,r3 // apply PAGE_MASK to EA (__PHX__ do we really need this?)
l.ori r4,r4,0x1 // set hardware valid bit: DTBL_MR entry
l.mtspr r5,r4,SPR_DTLBMR_BASE(0)
#ifndef CONFIG_DMMU_WORKS
l.addi r5,r5,1
l.andi r5,r5,0x3f
l.mtspr r5,r0,SPR_DTLBMR_BASE(0)
l.addi r5,r5,-2
l.andi r5,r5,0x3f
l.mtspr r5,r0,SPR_DTLBMR_BASE(0)
#endif
EXCEPTION_LOAD_GPR2
EXCEPTION_LOAD_GPR3
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
l.rfe
d_pmd_bad:
l.nop 1
EXCEPTION_LOAD_GPR2
EXCEPTION_LOAD_GPR3
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
l.rfe
d_pmd_none:
d_pte_not_present:
EXCEPTION_LOAD_GPR2
EXCEPTION_LOAD_GPR3
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
// __PHX__ for debugging purposes
DEBUG_TLB_PROBE(0x903)
l.j _dispatch_do_dpage_fault
l.nop
/* ==============================================[ ITLB miss handler ]=== */
.global _itlb_miss_handler
_itlb_miss_handler:
EXCEPTION_DEBUG_VALUE_ER(0xa00)
EXCEPTION_STORE_GPR2
EXCEPTION_STORE_GPR3
EXCEPTION_STORE_GPR4
EXCEPTION_STORE_GPR5
/*
* get EA of the miss
*/
l.mfspr r2,r0,SPR_EEAR_BASE
#ifndef CONFIG_IMMU_WORKS
// check for exception in delay slot and on page boundry
l.andi r3,r2,0x1fff // PAGE_SIZE - 1
l.sfeqi r3,0
l.bnf 1f
l.nop // we are on page boundry
l.mfspr r4,r0,SPR_EPCR_BASE
l.sfeq r4,r2
l.bf 1f // EPC and EEA are equal -> not in delay slot
l.nop
l.mfspr r5,r0,SPR_ESR_BASE // are we in user mode
l.andi r5,r5,SPR_SR_SM
l.sfeqi r5,0
l.bnf 2f // kernel mode
l.nop
// user mode: no fixup
EXCEPTION_STORE_GPR9
l.jal _emergency_print
l.ori r3,r0,lo(_string_pbjds) // page boundry, jump, delay slot
l.nop 0x1
l.j 1f
EXCEPTION_LOAD_GPR9
2:
EXCEPTION_STORE_GPR6
EXCEPTION_STORE_GPR9
// ok, we are in trouble...
l.jal _immu_trampoline_workaround
l.nop
EXCEPTION_LOAD_GPR2
EXCEPTION_LOAD_GPR3
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
EXCEPTION_LOAD_GPR6
EXCEPTION_LOAD_GPR9
l.rfe
1: // this is not delay slot exception of the page boundry
#endif
/*
* pmd = (pmd_t *)(current_pgd + pgd_index(daddr));
*
*/
GET_CURRENT_PGD(r3,r5) // r3 is current_pgd, r5 is temp
l.srli r4,r2,0x18 // >> PAGE_SHIFT + (PAGE_SHIFT - 2)
l.slli r4,r4,0x2 // to get address << 2
l.add r5,r4,r3 // r4 is pgd_index(daddr)
/*
* if (pmd_none(*pmd))
* goto pmd_none:
*/
tophys (r4,r5)
l.lwz r3,0x0(r4) // get *pmd value
l.sfne r3,r0
l.bnf i_pmd_none
l.andi r3,r3,0x1fff // ~PAGE_MASK
/*
* if (pmd_bad(*pmd))
* pmd_clear(pmd)
* goto pmd_bad:
*/
// l.sfeq r3,r0 // check *pmd value
// l.bf i_pmd_good
l.addi r3,r0,0xffffe000 // PAGE_MASK
// l.j i_pmd_bad
// l.sw 0x0(r4),r0 // clear pmd
i_pmd_good:
/*
* pte = *pte_offset(pmd, iaddr);
*
*/
l.lwz r4,0x0(r4) // get **pmd value
l.and r4,r4,r3 // & PAGE_MASK
l.srli r5,r2,0xd // >> PAGE_SHIFT, r2 == EEAR
l.andi r3,r5,0x7ff // (1UL << PAGE_SHIFT - 2) - 1
l.slli r3,r3,0x2 // to get address << 2
l.add r3,r3,r4
l.lwz r2,0x0(r3) // this is pte at last
/*
* if (!pte_present(pte))
*
*/
l.andi r4,r2,0x1
l.sfne r4,r0 // is pte present
l.bnf i_pte_not_present
l.addi r3,r0,0xffffe03e // PAGE_MASK | ITLB_UP_CONVERT_MASK
/*
* fill DTLB TR register
*/
l.and r4,r2,r3 // apply the mask
l.andi r3,r2,0x7c0 // _PAGE_EXEC | _PAGE_SRE | _PAGE_SWE | _PAGE_URE | _PAGE_UWE
// l.andi r3,r2,0x400 // _PAGE_EXEC
l.sfeq r3,r0
l.bf itlb_tr_fill //_workaround
l.andi r5,r5,0x3f // calc offset: & (NUM_TLB_ENTRIES-1), NUM_TLB_ENTRIES == 64
/*
* __PHX__ :: fixme
* we should not just blindly set executable flags,
* but it does help with ping. the clean way would be to find out
* (and fix it) why stack doesn't have execution permissions
*/
itlb_tr_fill_workaround:
l.ori r4,r4,0xc0 // | (SPR_ITLBTR_UXE | ITLBTR_SXE)
itlb_tr_fill:
l.mtspr r5,r4,SPR_ITLBTR_BASE(0)
/*
* fill DTLB MR register
*/
l.mfspr r2,r0,SPR_EEAR_BASE
l.addi r3,r0,0xffffe000 // PAGE_MASK
l.and r4,r2,r3 // apply PAGE_MASK to EA (__PHX__ do we really need this?)
l.ori r4,r4,0x1 // set hardware valid bit: DTBL_MR entry
l.mtspr r5,r4,SPR_ITLBMR_BASE(0)
#ifndef CONFIG_IMMU_WORKS
l.addi r5,r5,1
l.andi r5,r5,0x3f
l.mtspr r5,r0,SPR_ITLBMR_BASE(0)
l.addi r5,r5,-2
l.andi r5,r5,0x3f
l.mtspr r5,r0,SPR_ITLBMR_BASE(0)
#endif
EXCEPTION_LOAD_GPR2
EXCEPTION_LOAD_GPR3
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
l.rfe
i_pmd_bad:
l.nop 1
EXCEPTION_LOAD_GPR2
EXCEPTION_LOAD_GPR3
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
l.rfe
i_pmd_none:
i_pte_not_present:
EXCEPTION_LOAD_GPR2
EXCEPTION_LOAD_GPR3
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
// __PHX__ for debugging purposes
DEBUG_TLB_PROBE(0xa04)
l.j _dispatch_do_ipage_fault
l.nop
/* ==============================================[ boot tlb handlers ]=== */
/* ---[ boot dtlb miss handler ]----------------------------------------- */
boot_dtlb_miss_handler:
/* mask for DTLB_MR register: - (0) sets V (valid) bit,
* - (31-12) sets bits belonging to VPN (31-12)
*/
#define DTLB_MR_MASK 0xfffff001
/* mask for DTLB_TR register: - (2) sets CI (cache inhibit) bit,
* - (4) sets A (access) bit,
* - (5) sets D (dirty) bit,
* - (8) sets SRE (superuser read) bit
* - (9) sets SWE (superuser write) bit
* - (31-12) sets bits belonging to VPN (31-12)
*/
#define DTLB_TR_MASK 0xfffff332
#define VPN_MASK 0xfffff000
#define PPN_MASK 0xfffff000
/*
* a % 64 = a & MOD_64_MASK
*/
#define MOD_64_MASK 0x3f
#define MOD_64(dest,src) \
l.andi dest,src,MOD_64_MASK
EXCEPTION_DEBUG_VALUE_ER(0x9b0)
EXCEPTION_STORE_GPR6
l.mfspr r6,r0,SPR_ESR_BASE //
l.andi r6,r6,SPR_SR_SM // are we in kernel mode ?
l.sfeqi r6,0 // r6 == 0x1 --> SM
l.bf exit_with_no_dtranslation //
l.nop
/* this could be optimized by moving storing of
* non r6 registers here, and jumping r6 restore
* if not in supervisor mode
*/
EXCEPTION_STORE_GPR2
EXCEPTION_STORE_GPR3
EXCEPTION_STORE_GPR4
EXCEPTION_STORE_GPR5
l.mfspr r4,r0,SPR_EEAR_BASE // get the offending EA
/* do not do any translation if EA is above DRAM_END */
LOAD_SYMBOL_2_GPR(r6,DRAM_END)
l.sfgtu r4,r6 // flag if EA larger than DRAM_END
l.bf exit_with_no_dtranslation
/* delay slot */
immediate_translation:
CLEAR_GPR(r6)
l.srli r3,r4,0xd // r3 <- r4 / 8192 (sets are relative to page size (8Kb) NOT VPN size (4Kb)
l.andi r2,r3,MOD_64_MASK // r2 <- r3 % 64: ok this is SET
l.or r6,r6,r4 // r6 <- r4
l.ori r6,r6,~(VPN_MASK) // r6 <- VPN :VPN .xfff - clear up lo(r6) to 0x**** *fff
l.movhi r5,hi(DTLB_MR_MASK) // r5 <- ffff:0000.x000
l.ori r5,r5,lo(DTLB_MR_MASK) // r5 <- ffff:1111.x001 - apply DTLB_MR_MASK
l.and r5,r5,r6 // r5 <- VPN :VPN .x001 - we have DTLBMR entry
l.mtspr r2,r5,SPR_DTLBMR_BASE(0) // set DTLBMR
/* set up DTLB with no translation for EA <= 0xbfffffff */
LOAD_SYMBOL_2_GPR(r6,0xbfffffff)
l.sfgeu r6,r4 // flag if r6 >= r4 (if 0xbfffffff >= EA)
l.bf 1f // goto out
l.and r3,r4,r4 // delay slot :: 24 <- r4 (if flag==1)
tophys(r3,r4) // r3 <- PA
1:
l.ori r3,r3,~(PPN_MASK) // r3 <- PPN :PPN .xfff - clear up lo(r6) to 0x**** *fff
l.movhi r5,hi(DTLB_TR_MASK) // r5 <- ffff:0000.x000
l.ori r5,r5,lo(DTLB_TR_MASK) // r5 <- ffff:1111.x330 - apply DTLB_MR_MASK
l.and r5,r5,r3 // r5 <- PPN :PPN .x330 - we have DTLBTR entry
l.mtspr r2,r5,SPR_DTLBTR_BASE(0) // set DTLBTR
#ifndef CONFIG_DMMU_WORKS
l.addi r2,r2,1
l.andi r2,r2,0x3f
l.mtspr r2,r0,SPR_DTLBMR_BASE(0)
l.addi r2,r2,-2
l.andi r2,r2,0x3f
l.mtspr r2,r0,SPR_DTLBMR_BASE(0)
#endif
EXCEPTION_LOAD_GPR6
EXCEPTION_LOAD_GPR5
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR3
EXCEPTION_LOAD_GPR2
l.rfe // SR <- ESR, PC <- EPC
exit_with_no_dtranslation:
/* EA out of memory or not in supervisor mode */
EXCEPTION_LOAD_GPR6
EXCEPTION_LOAD_GPR4
l.j _dispatch_bus_fault
/* ---[ boot itlb miss handler ]----------------------------------------- */
boot_itlb_miss_handler:
/* mask for ITLB_MR register: - sets V (valid) bit,
* - sets bits belonging to VPN (15-12)
*/
#define ITLB_MR_MASK 0xfffff001
/* mask for ITLB_TR register: - sets A (access) bit,
* - sets SXE (superuser execute) bit
* - sets bits belonging to VPN (15-12)
*/
#define ITLB_TR_MASK 0xfffff050
#define VPN_MASK 0xfffff000
#define PPN_MASK 0xfffff000
/*
* a % 64 = a & MOD_64_MASK
*/
#define MOD_64_MASK 0x3f
#define MOD_64(dest,src) \
l.andi dest,src,MOD_64_MASK
EXCEPTION_DEBUG_VALUE_ER(0xab0)
EXCEPTION_STORE_GPR2
EXCEPTION_STORE_GPR3
EXCEPTION_STORE_GPR4
EXCEPTION_STORE_GPR5
EXCEPTION_STORE_GPR6
l.mfspr r6,r0,SPR_ESR_BASE //
l.andi r6,r6,SPR_SR_SM // are we in kernel mode ?
l.sfeqi r6,0 // r6 == 0x1 --> SM
l.bf exit_with_no_itranslation
l.nop
#ifndef CONFIG_IMMU_WORKS
l.mfspr r2,r0,SPR_EEAR_BASE
// check for exception in delay slot and on page boundry
l.andi r3,r2,0x1fff // PAGE_SIZE - 1
l.sfeqi r3,0
l.bnf 1f
l.nop // we are on page boundry
l.mfspr r4,r0,SPR_EPCR_BASE
l.sfeq r4,r2
l.bf 1f // EPC and EEA are equal -> not in delay slot
l.nop
EXCEPTION_STORE_GPR6
EXCEPTION_STORE_GPR9
// ok, we are in trouble...
l.jal _immu_trampoline_workaround
l.nop
EXCEPTION_LOAD_GPR2
EXCEPTION_LOAD_GPR3
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
EXCEPTION_LOAD_GPR6
EXCEPTION_LOAD_GPR9
l.rfe
1: // this is not delay slot exception of the page boundry
#endif
l.mfspr r4,r0,SPR_EEAR_BASE // get the offending EA
/* do not do any translation if EA is above DRAM_END */
LOAD_SYMBOL_2_GPR(r6,DRAM_END)
l.sfgtu r4,r6 // flag if EA larger than DRAM_END
l.bf exit_with_no_itranslation
l.nop
CLEAR_GPR(r6)
l.srli r3,r4,0xd // r3 <- r4 / 8192 (sets are relative to page size (8Kb) NOT VPN size (4Kb)
l.andi r2,r3,MOD_64_MASK // r2 <- r3 % 64: ok this is SET
l.or r6,r6,r4 // r6 <- r4
l.ori r6,r6,~(VPN_MASK) // r6 <- VPN :VPN .xfff - clear up lo(r6) to 0x**** *fff
l.movhi r5,hi(ITLB_MR_MASK) // r5 <- ffff:0000.x000
l.ori r5,r5,lo(ITLB_MR_MASK) // r5 <- ffff:1111.x001 - apply ITLB_MR_MASK
l.and r5,r5,r6 // r5 <- VPN :VPN .x001 - we have ITLBMR entry
l.mtspr r2,r5,SPR_ITLBMR_BASE(0) // set ITLBMR
/*
* set up ITLB with no translation for EA <= 0x0fffffff
*
* we need this for head.S mapping (EA = PA). if we move all functions
* which run with mmu enabled into entry.S, we might be able to eliminate this.
*
*/
LOAD_SYMBOL_2_GPR(r6,0x0fffffff)
l.sfgeu r6,r4 // flag if r6 >= r4 (if 0xb0ffffff >= EA)
l.bf 1f // goto out
l.and r3,r4,r4 // delay slot :: 24 <- r4 (if flag==1)
tophys(r3,r4) // r3 <- PA
1:
l.ori r3,r3,~(PPN_MASK) // r3 <- PPN :PPN .xfff - clear up lo(r6) to 0x**** *fff
l.movhi r5,hi(ITLB_TR_MASK) // r5 <- ffff:0000.x000
l.ori r5,r5,lo(ITLB_TR_MASK) // r5 <- ffff:1111.x050 - apply ITLB_MR_MASK
l.and r5,r5,r3 // r5 <- PPN :PPN .x050 - we have ITLBTR entry
l.mtspr r2,r5,SPR_ITLBTR_BASE(0) // set ITLBTR
#ifndef CONFIG_IMMU_WORKS
l.addi r2,r2,1
l.andi r2,r2,0x3f
l.mtspr r2,r0,SPR_ITLBMR_BASE(0)
l.addi r2,r2,-2
l.andi r2,r2,0x3f
l.mtspr r2,r0,SPR_ITLBMR_BASE(0)
#endif
EXCEPTION_LOAD_GPR6
EXCEPTION_LOAD_GPR5
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR3
EXCEPTION_LOAD_GPR2
l.rfe // SR <- ESR, PC <- EPC
exit_with_no_itranslation:
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR6
l.j _dispatch_bus_fault
l.nop
/* =================================================[ debugging aids ]=== */
.align 64
_immu_trampoline:
.space 64
_immu_trampoline_top:
#define TRAMP_SLOT_0 (0x0)
#define TRAMP_SLOT_1 (0x4)
#define TRAMP_SLOT_2 (0x8)
#define TRAMP_SLOT_3 (0xc)
#define TRAMP_SLOT_4 (0x10)
#define TRAMP_SLOT_5 (0x14)
#define TRAMP_FRAME_SIZE (0x18)
ENTRY(_immu_trampoline_workaround)
// r2 EEA
// r6 is physical EEA
tophys(r6,r2)
LOAD_SYMBOL_2_GPR(r5,_immu_trampoline)
tophys (r3,r5) // r3 is trampoline (physical)
LOAD_SYMBOL_2_GPR(r4,0x15000000)
l.sw (TRAMP_SLOT_0)r3,r4
l.sw (TRAMP_SLOT_1)r3,r4
l.sw (TRAMP_SLOT_4)r3,r4
l.sw (TRAMP_SLOT_5)r3,r4
// EPC = EEA - 0x4
l.lwz r4,(0x0)r6 // load op @ EEA + 0x0 (fc address)
l.sw (TRAMP_SLOT_3)r3,r4 // store it to _immu_trampoline_data
l.lwz r4,(-0x4)r6 // load op @ EEA - 0x4 (f8 address)
l.sw (TRAMP_SLOT_2)r3,r4 // store it to _immu_trampoline_data
l.srli r5,r4,26 // check opcode for write access
l.sfeqi r5,0 // l.j
l.bf 0f
l.sfeqi r5,0x11 // l.jr
l.bf 1f
l.sfeqi r5,1 // l.jal
l.bf 2f
l.sfeqi r5,0x12 // l.jalr
l.bf 3f
l.sfeqi r5,3 // l.bnf
l.bf 4f
l.sfeqi r5,4 // l.bf
l.bf 5f
99:
l.nop
l.j 99b // should never happen
l.nop 1
// r2 is EEA
// r3 is trampoline address (physical)
// r4 is instruction
// r6 is physical(EEA)
//
// r5
2: // l.jal
/* 19 20 aa aa l.movhi r9,0xaaaa
* a9 29 bb bb l.ori r9,0xbbbb
*
* where 0xaaaabbbb is EEA + 0x4 shifted right 2
*/
l.addi r6,r2,0x4 // this is 0xaaaabbbb
// l.movhi r9,0xaaaa
l.ori r5,r0,0x1920 // 0x1920 == l.movhi r9
l.sh (TRAMP_SLOT_0+0x0)r3,r5
l.srli r5,r6,16
l.sh (TRAMP_SLOT_0+0x2)r3,r5
// l.ori r9,0xbbbb
l.ori r5,r0,0xa929 // 0xa929 == l.ori r9
l.sh (TRAMP_SLOT_1+0x0)r3,r5
l.andi r5,r6,0xffff
l.sh (TRAMP_SLOT_1+0x2)r3,r5
/* falthrough, need to set up new jump offset */
0: // l.j
l.slli r6,r4,6 // original offset shifted left 6 - 2
// l.srli r6,r6,6 // original offset shifted right 2
l.slli r4,r2,4 // old jump position: EEA shifted left 4
// l.srli r4,r4,6 // old jump position: shifted right 2
l.addi r5,r3,0xc // new jump position (physical)
l.slli r5,r5,4 // new jump position: shifted left 4
// calculate new jump offset
// new_off = old_off + (old_jump - new_jump)
l.sub r5,r4,r5 // old_jump - new_jump
l.add r5,r6,r5 // orig_off + (old_jump - new_jump)
l.srli r5,r5,6 // new offset shifted right 2
// r5 is new jump offset
// l.j has opcode 0x0...
l.sw (TRAMP_SLOT_2)r3,r5 // write it back
l.j trampoline_out
l.nop
/* ----------------------------- */
3: // l.jalr
/* 19 20 aa aa l.movhi r9,0xaaaa
* a9 29 bb bb l.ori r9,0xbbbb
*
* where 0xaaaabbbb is EEA + 0x4 shifted right 2
*/
l.addi r6,r2,0x4 // this is 0xaaaabbbb
// l.movhi r9,0xaaaa
l.ori r5,r0,0x1920 // 0x1920 == l.movhi r9
l.sh (TRAMP_SLOT_0+0x0)r3,r5
l.srli r5,r6,16
l.sh (TRAMP_SLOT_0+0x2)r3,r5
// l.ori r9,0xbbbb
l.ori r5,r0,0xa929 // 0xa929 == l.ori r9
l.sh (TRAMP_SLOT_1+0x0)r3,r5
l.andi r5,r6,0xffff
l.sh (TRAMP_SLOT_1+0x2)r3,r5
l.lhz r5,(TRAMP_SLOT_2+0x0)r3 // load hi part of jump instruction
l.andi r5,r5,0x3ff // clear out opcode part
l.ori r5,r5,0x4400 // opcode changed from l.jalr -> l.jr
l.sh (TRAMP_SLOT_2+0x0)r3,r5 // write it back
/* falthrough */
1: // l.jr
l.j trampoline_out
l.nop
/* ----------------------------- */
4: // l.bnf
5: // l.bf
l.slli r6,r4,6 // original offset shifted left 6 - 2
// l.srli r6,r6,6 // original offset shifted right 2
l.slli r4,r2,4 // old jump position: EEA shifted left 4
// l.srli r4,r4,6 // old jump position: shifted right 2
l.addi r5,r3,0xc // new jump position (physical)
l.slli r5,r5,4 // new jump position: shifted left 4
// calculate new jump offset
// new_off = old_off + (old_jump - new_jump)
l.add r6,r6,r4 // (orig_off + old_jump)
l.sub r6,r6,r5 // (orig_off + old_jump) - new_jump
l.srli r6,r6,6 // new offset shifted right 2
// r6 is new jump offset
l.lwz r4,(TRAMP_SLOT_2+0x0)r3 // load jump instruction
l.srli r4,r4,16
l.andi r4,r4,0xfc00 // get opcode part
l.slli r4,r4,16
l.or r6,r4,r6 // l.b(n)f new offset
l.sw (TRAMP_SLOT_2)r3,r6 // write it back
/* we need to add l.j to EEA + 0x8 */
tophys (r4,r2) // may not be needed (due to shifts down_
l.addi r4,r4,(0x8 - 0x8) // jump target = r2 + 0x8 (compensate for 0x8)
// jump position = r5 + 0x8 (0x8 compensated)
l.sub r4,r4,r5 // jump offset = target - new_position + 0x8
l.slli r4,r4,4 // the amount of info in imediate of jump
l.srli r4,r4,6 // jump instruction with offset
l.sw (TRAMP_SLOT_4)r3,r4 // write it to 4th slot
/* fallthrough */
trampoline_out:
// set up new EPC to point to our trampoline code
LOAD_SYMBOL_2_GPR(r5,_immu_trampoline)
l.mtspr r0,r5,SPR_EPCR_BASE
// immu_trampoline is (4x) CACHE_LINE aligned
// and only 6 instructions long,
// so we need to invalidate only 2 lines
l.mtspr r0,r5,SPR_ICBIR
l.addi r5,r5,IC_LINE
l.mtspr r0,r5,SPR_ICBIR
l.jr r9
l.nop
/*
* dumping processor state without mmu
* (not yet finnished)
*/
ENTRY(_debug_tng)
l.addi r1,r1,-16
l.sw 0(r1),r3
l.sw 4(r1),r4
l.mfspr r3,r0,SPR_SR
l.sw 8(r1),r3
l.mfspr r3,r0,SPR_PC
l.sw 12(r1),r3
l.ori r3,r0,0x8001
l.mtspr r0,r3,SPR_ESR_BASE
LOAD_SYMBOL_2_GPR(r3,nommu_entry)
tophys (r4,r3)
l.mtspr r0,r4,SPR_EPCR_BASE
l.lwz r3,0(r1)
l.lwz r4,4(r1)
l.addi r1,r1,8
l.rfe
nommu_entry:
EXCEPTION_T_STORE_GPR31
EXCEPTION_T_STORE_GPR2
EXCEPTION_T_STORE_SP
/* temporary store r3, r9 into r1, r2 */
l.addi r1,r3,0x0
l.addi r2,r9,0x0
/* the string referenced by r3 must be low enough */
l.jal _emergency_print
l.ori r3,r0,lo(_string_ed)
l.mfspr r3,r0,SPR_PC
l.jal _emergency_print_nr
l.andi r3,r3,0x1f00
/* the string referenced by r3 must be low enough */
l.jal _emergency_print
l.ori r3,r0,lo(_string_epc_prefix)
l.jal _emergency_print_nr
l.mfspr r3,r0,SPR_EPCR_BASE
l.jal _emergency_print
l.ori r3,r0,lo(_string_nl)
/* end of printing */
l.addi r3,r1,0x0
l.addi r9,r2,0x0
/* extract current, ksp from current_set */
LOAD_SYMBOL_2_GPR(r1,_unhandled_stack_top)
/* create new stack frame, save only needed gprs */
/* r1: KSP, r2: current, r31: __pa(KSP) */
/* r12: temp, syscall indicator, r13 temp */
l.addi r1,r1,-(INT_FRAME_SIZE)
/* r1 is KSP, r31 is __pa(KSP) */
tophys (r31,r1)
l.sw GPR12(r31),r12
l.mfspr r12,r0,SPR_EPCR_BASE
l.sw PC(r31),r12
l.mfspr r12,r0,SPR_ESR_BASE
l.sw SR(r31),r12
/* save r31 */
EXCEPTION_T_LOAD_GPR31(r12)
l.sw GPR31(r31),r12
/* save r2 as was prior to exception */
EXCEPTION_T_LOAD_GPR2(r12)
l.sw GPR2(r31),r12
/* save SP as was prior to exception */
EXCEPTION_T_LOAD_SP(r12)
l.sw SP(r31),r12
l.sw GPR13(r31),r13
/* --> */
/* save exception r4, set r4 = EA */
l.sw GPR4(r31),r4
l.mfspr r4,r0,SPR_EEAR_BASE
/* r31 is __pa(r1), r1 <- r31 */
l.addi r1,r31,0x0
/* r1, r2, EPCR, ESR a already saved */
l.sw GPR3(r1),r3
l.sw ORIG_GPR3(r1),r3
l.sw GPR5(r1),r5
l.sw GPR6(r1),r6
l.sw GPR7(r1),r7
l.sw GPR8(r1),r8
l.sw GPR9(r1),r9
l.sw GPR10(r1),r10
l.sw GPR11(r1),r11
/* r12,r13 already saved */
l.sw GPR14(r1),r14
l.sw GPR15(r1),r15
l.sw GPR16(r1),r16
l.sw GPR17(r1),r17
l.sw GPR18(r1),r18
l.sw GPR19(r1),r19
l.sw GPR20(r1),r20
l.sw GPR21(r1),r21
l.sw GPR22(r1),r22
l.sw GPR23(r1),r23
l.sw GPR24(r1),r24
l.sw GPR25(r1),r25
l.sw GPR26(r1),r26
l.sw GPR27(r1),r27
l.sw GPR28(r1),r28
l.sw GPR29(r1),r29
l.sw GPR30(r1),r30
/* r31 already saved */
l.sw RESULT(r1),r0
l.addi r3,r1,0
/* r4 is exception EA */
l.addi r5,r0,0xdead
l.jal _nommu_dump_state
l.nop
/* ========================================[ standard debugging aids ]=== */
// this HAS to be atomic. also disable interrupts beetwen to entries
// may use gpr4
ENTRY(_exception_regenerate)
E_REGEN_LOAD_STATUS(r4) // were we in this exception yet
l.sfeqi r4,0x0
l.bnf 1f
l.nop
0: // first entry into this exception
// patch the ESR, reenter exception
l.mfspr r4,r0,SPR_ESR_BASE // get original ESR
E_REGEN_STORE_STATUS(r4) // save original ESR
SPR_DISABLE_LO_BITS(SPR_ESR_BASE,
(SPR_SR_ICE | SPR_SR_DCE | SPR_SR_IEE | SPR_SR_TEE),r4)
SPR_DISABLE_LO_BITS(SPR_SR,
(SPR_SR_ICE | SPR_SR_DCE | SPR_SR_IEE | SPR_SR_TEE),r4)
EXCEPTION_DEBUG_LOAD_GPR4
EXCEPTION_DEBUG_LOAD_F_GPR9
l.rfe // this will regenerate exception
1: // second entry into this exception
// patch ESR, invalidate the caches
// we already loaded previous ESR into r4
l.mtspr r0,r4,SPR_ESR_BASE
l.ori r4,r0,0x0 // next time is fresh entry
E_REGEN_STORE_STATUS(r4) // prepare for next exception
E_REGEN_STORE_GPR3
E_REGEN_STORE_GPR4
E_REGEN_STORE_GPR5
E_REGEN_STORE_GPR6
E_REGEN_STORE_GPR9
l.jal _dc_enable
l.nop
l.jal _ic_enable
l.nop
E_REGEN_LOAD_GPR3
E_REGEN_LOAD_GPR4
E_REGEN_LOAD_GPR5
E_REGEN_LOAD_GPR6
E_REGEN_LOAD_GPR9
l.jr r9
l.nop
ENTRY(_exception_debug)
EXCEPTION_DEBUG_STORE_GPR3
EXCEPTION_DEBUG_STORE_GPR9
// disable tick timer
l.mfspr r3,r0,SPR_TTMR
LOAD_SYMBOL_2_GPR(r9,~(0x30000003))
l.and r3,r3,r9
l.mtspr r0,r3,SPR_TTMR
l.jal _emergency_print
l.ori r3,r0,lo(_string_debug_exception)
l.jal _emergency_print_nr
l.andi r3,r4,0x1ff0
/* the string referenced by r3 must be low enough */
l.jal _emergency_print
l.ori r3,r0,lo(_string_epc_prefix)
l.jal _emergency_print_nr
l.mfspr r3,r0,SPR_EPCR_BASE
l.jal _emergency_print
l.ori r3,r0,lo(_string_debug_esr_prefix)
l.jal _emergency_print_nr
l.mfspr r3,r0,SPR_ESR_BASE
l.jal _emergency_print
l.ori r3,r0,lo(_string_debug_eear_prefix)
l.jal _emergency_print_nr
l.mfspr r3,r0,SPR_EEAR_BASE
l.jal _emergency_print
l.ori r3,r0,lo(_string_nl)
// enable tick timer
l.mfspr r3,r0,SPR_TTMR
LOAD_SYMBOL_2_GPR(r9,0x20000001)
l.or r3,r3,r9
l.mtspr r0,r3,SPR_TTMR
EXCEPTION_DEBUG_LOAD_GPR3
EXCEPTION_DEBUG_LOAD_GPR9
l.jr r9
l.nop
/*
* DSCR: prints a string referenced by r3.
*
* PRMS: r3 - address of the first character of null
* terminated string to be printed
*
* PREQ: UART at UART_BASE_ADD has to be initialized
*
* POST: caller should be aware that r3, r9 are changed
*/
ENTRY(_emergency_print)
EMERGENCY_PRINT_STORE_GPR4
EMERGENCY_PRINT_STORE_GPR5
EMERGENCY_PRINT_STORE_GPR6
EMERGENCY_PRINT_STORE_GPR7
2:
l.lbz r7,0(r3)
l.sfeq r7,r0
l.bf 9f
l.nop
// putc:
l.movhi r4,hi(UART_BASE_ADD)
l.addi r6,r0,0x20
1: l.lbz r5,5(r4)
l.andi r5,r5,0x20
l.sfeq r5,r6
l.bnf 1b
l.nop
l.sb 0(r4),r7
l.addi r6,r0,0x60
1: l.lbz r5,5(r4)
l.andi r5,r5,0x60
l.sfeq r5,r6
l.bnf 1b
l.nop
/* next character */
l.j 2b
l.addi r3,r3,0x1
9:
EMERGENCY_PRINT_LOAD_GPR7
EMERGENCY_PRINT_LOAD_GPR6
EMERGENCY_PRINT_LOAD_GPR5
EMERGENCY_PRINT_LOAD_GPR4
l.jr r9
l.nop
ENTRY(_emergency_print_nr)
EMERGENCY_PRINT_STORE_GPR4
EMERGENCY_PRINT_STORE_GPR5
EMERGENCY_PRINT_STORE_GPR6
EMERGENCY_PRINT_STORE_GPR7
EMERGENCY_PRINT_STORE_GPR8
l.addi r8,r0,32 // shift register
1: /* remove leading zeros */
l.addi r8,r8,-0x4
l.srl r7,r3,r8
l.andi r7,r7,0xf
/* don't skip the last zero if number == 0x0 */
l.sfeqi r8,0x4
l.bf 2f
l.nop
l.sfeq r7,r0
l.bf 1b
l.nop
2:
l.srl r7,r3,r8
l.andi r7,r7,0xf
l.sflts r8,r0
l.bf 9f
l.sfgtui r7,0x9
l.bnf 8f
l.nop
l.addi r7,r7,0x27
8:
l.addi r7,r7,0x30
// putc:
l.movhi r4,hi(UART_BASE_ADD)
l.addi r6,r0,0x20
1: l.lbz r5,5(r4)
l.andi r5,r5,0x20
l.sfeq r5,r6
l.bnf 1b
l.nop
l.sb 0(r4),r7
l.addi r6,r0,0x60
1: l.lbz r5,5(r4)
l.andi r5,r5,0x60
l.sfeq r5,r6
l.bnf 1b
l.nop
/* next character */
l.j 2b
l.addi r8,r8,-0x4
9:
EMERGENCY_PRINT_LOAD_GPR8
EMERGENCY_PRINT_LOAD_GPR7
EMERGENCY_PRINT_LOAD_GPR6
EMERGENCY_PRINT_LOAD_GPR5
EMERGENCY_PRINT_LOAD_GPR4
l.jr r9
l.nop
ENTRY(_early_uart_init)
l.movhi r3,hi(UART_BASE_ADD)
l.addi r4,r0,0x7
l.sb 0x2(r3),r4
l.addi r4,r0,0x0
l.sb 0x1(r3),r4
l.addi r4,r0,0x3
l.sb 0x3(r3),r4
l.lbz r5,3(r3)
l.ori r4,r5,0x80
l.sb 0x3(r3),r4
l.addi r4,r0,((UART_DEVISOR>>8) & 0x000000ff)
l.sb UART_DLM(r3),r4
l.addi r4,r0,((UART_DEVISOR) & 0x000000ff)
l.sb UART_DLL(r3),r4
l.sb 0x3(r3),r5
l.jr r9
l.nop
_string_copying_linux:
.string "\n\n\n\n\n\rCopying Linux... \0"
_string_ok_booting:
.string "Ok, booting the kernel.\n\r\0"
_string_unhandled_exception:
.string "\n\rRunarunaround: Unhandled exception 0x\0"
_string_epc_prefix:
.string ": EPC=0x\0"
_string_nl:
.string "\n\r\0"
_string_debug_exception:
.string "\n\r\tDebug: exception 0x\0"
_string_debug_esr_prefix:
.string ", ESR=0x\0"
_string_debug_eear_prefix:
.string ", EEAR=0x\0"
_string_dcache_clean:
.string "dcache cleaning\n\r\0"
_string_icache_clean:
.string "icache cleaning\n\r\0"
_string_ic_invalidate:
.string "\n\r\tic invalidate: \0"
_string_ic_enable:
.string "\n\ricache enabling\n\r\0"
_string_dc_invalidate:
.string "\n\r\tdc invalidate: \0"
_string_dc_enable:
.string "\n\rdcache enabling\n\r\0"
_string_pbjds:
.string "[jd]"
_string_ed:
.string "\n\r[debug] "
.global _string_esr_irq_bug
_string_esr_irq_bug:
.string "\n\rESR external interrupt bug, for details look into entry.S\n\r\0"
/* ========================================[ page aligned structures ]=== */
/*
* .data section should be page aligned
* (look into arch/or32/kernel/vmlinux.lds)
*/
.data
.global _sdata
_sdata:
.align 8192
.global _empty_zero_page
_empty_zero_page:
.space 8192
.global _swapper_pg_dir
_swapper_pg_dir:
.space 8192
.global _unhandled_stack
_unhandled_stack:
.space 8192
_unhandled_stack_top:
/* ============================================================[ EOF ]=== */
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