qemu-e2k/target-mips/helper.c
Nathan Froyd 32188a03da target-mips: change interrupt bits to be mips16-aware
We need to stash the operating mode into the low bit of the error PC and
restore it on return from interrupts.

Signed-off-by: Nathan Froyd <froydnj@codesourcery.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2009-12-13 20:20:19 +01:00

657 lines
21 KiB
C

/*
* MIPS emulation helpers for qemu.
*
* Copyright (c) 2004-2005 Jocelyn Mayer
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include <signal.h>
#include "cpu.h"
#include "exec-all.h"
enum {
TLBRET_DIRTY = -4,
TLBRET_INVALID = -3,
TLBRET_NOMATCH = -2,
TLBRET_BADADDR = -1,
TLBRET_MATCH = 0
};
/* no MMU emulation */
int no_mmu_map_address (CPUState *env, target_phys_addr_t *physical, int *prot,
target_ulong address, int rw, int access_type)
{
*physical = address;
*prot = PAGE_READ | PAGE_WRITE;
return TLBRET_MATCH;
}
/* fixed mapping MMU emulation */
int fixed_mmu_map_address (CPUState *env, target_phys_addr_t *physical, int *prot,
target_ulong address, int rw, int access_type)
{
if (address <= (int32_t)0x7FFFFFFFUL) {
if (!(env->CP0_Status & (1 << CP0St_ERL)))
*physical = address + 0x40000000UL;
else
*physical = address;
} else if (address <= (int32_t)0xBFFFFFFFUL)
*physical = address & 0x1FFFFFFF;
else
*physical = address;
*prot = PAGE_READ | PAGE_WRITE;
return TLBRET_MATCH;
}
/* MIPS32/MIPS64 R4000-style MMU emulation */
int r4k_map_address (CPUState *env, target_phys_addr_t *physical, int *prot,
target_ulong address, int rw, int access_type)
{
uint8_t ASID = env->CP0_EntryHi & 0xFF;
int i;
for (i = 0; i < env->tlb->tlb_in_use; i++) {
r4k_tlb_t *tlb = &env->tlb->mmu.r4k.tlb[i];
/* 1k pages are not supported. */
target_ulong mask = tlb->PageMask | ~(TARGET_PAGE_MASK << 1);
target_ulong tag = address & ~mask;
target_ulong VPN = tlb->VPN & ~mask;
#if defined(TARGET_MIPS64)
tag &= env->SEGMask;
#endif
/* Check ASID, virtual page number & size */
if ((tlb->G == 1 || tlb->ASID == ASID) && VPN == tag) {
/* TLB match */
int n = !!(address & mask & ~(mask >> 1));
/* Check access rights */
if (!(n ? tlb->V1 : tlb->V0))
return TLBRET_INVALID;
if (rw == 0 || (n ? tlb->D1 : tlb->D0)) {
*physical = tlb->PFN[n] | (address & (mask >> 1));
*prot = PAGE_READ;
if (n ? tlb->D1 : tlb->D0)
*prot |= PAGE_WRITE;
return TLBRET_MATCH;
}
return TLBRET_DIRTY;
}
}
return TLBRET_NOMATCH;
}
#if !defined(CONFIG_USER_ONLY)
static int get_physical_address (CPUState *env, target_phys_addr_t *physical,
int *prot, target_ulong address,
int rw, int access_type)
{
/* User mode can only access useg/xuseg */
int user_mode = (env->hflags & MIPS_HFLAG_MODE) == MIPS_HFLAG_UM;
int supervisor_mode = (env->hflags & MIPS_HFLAG_MODE) == MIPS_HFLAG_SM;
int kernel_mode = !user_mode && !supervisor_mode;
#if defined(TARGET_MIPS64)
int UX = (env->CP0_Status & (1 << CP0St_UX)) != 0;
int SX = (env->CP0_Status & (1 << CP0St_SX)) != 0;
int KX = (env->CP0_Status & (1 << CP0St_KX)) != 0;
#endif
int ret = TLBRET_MATCH;
#if 0
qemu_log("user mode %d h %08x\n", user_mode, env->hflags);
#endif
if (address <= (int32_t)0x7FFFFFFFUL) {
/* useg */
if (env->CP0_Status & (1 << CP0St_ERL)) {
*physical = address & 0xFFFFFFFF;
*prot = PAGE_READ | PAGE_WRITE;
} else {
ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
}
#if defined(TARGET_MIPS64)
} else if (address < 0x4000000000000000ULL) {
/* xuseg */
if (UX && address <= (0x3FFFFFFFFFFFFFFFULL & env->SEGMask)) {
ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
} else {
ret = TLBRET_BADADDR;
}
} else if (address < 0x8000000000000000ULL) {
/* xsseg */
if ((supervisor_mode || kernel_mode) &&
SX && address <= (0x7FFFFFFFFFFFFFFFULL & env->SEGMask)) {
ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
} else {
ret = TLBRET_BADADDR;
}
} else if (address < 0xC000000000000000ULL) {
/* xkphys */
if (kernel_mode && KX &&
(address & 0x07FFFFFFFFFFFFFFULL) <= env->PAMask) {
*physical = address & env->PAMask;
*prot = PAGE_READ | PAGE_WRITE;
} else {
ret = TLBRET_BADADDR;
}
} else if (address < 0xFFFFFFFF80000000ULL) {
/* xkseg */
if (kernel_mode && KX &&
address <= (0xFFFFFFFF7FFFFFFFULL & env->SEGMask)) {
ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
} else {
ret = TLBRET_BADADDR;
}
#endif
} else if (address < (int32_t)0xA0000000UL) {
/* kseg0 */
if (kernel_mode) {
*physical = address - (int32_t)0x80000000UL;
*prot = PAGE_READ | PAGE_WRITE;
} else {
ret = TLBRET_BADADDR;
}
} else if (address < (int32_t)0xC0000000UL) {
/* kseg1 */
if (kernel_mode) {
*physical = address - (int32_t)0xA0000000UL;
*prot = PAGE_READ | PAGE_WRITE;
} else {
ret = TLBRET_BADADDR;
}
} else if (address < (int32_t)0xE0000000UL) {
/* sseg (kseg2) */
if (supervisor_mode || kernel_mode) {
ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
} else {
ret = TLBRET_BADADDR;
}
} else {
/* kseg3 */
/* XXX: debug segment is not emulated */
if (kernel_mode) {
ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
} else {
ret = TLBRET_BADADDR;
}
}
#if 0
qemu_log(TARGET_FMT_lx " %d %d => " TARGET_FMT_lx " %d (%d)\n",
address, rw, access_type, *physical, *prot, ret);
#endif
return ret;
}
#endif
static void raise_mmu_exception(CPUState *env, target_ulong address,
int rw, int tlb_error)
{
int exception = 0, error_code = 0;
switch (tlb_error) {
default:
case TLBRET_BADADDR:
/* Reference to kernel address from user mode or supervisor mode */
/* Reference to supervisor address from user mode */
if (rw)
exception = EXCP_AdES;
else
exception = EXCP_AdEL;
break;
case TLBRET_NOMATCH:
/* No TLB match for a mapped address */
if (rw)
exception = EXCP_TLBS;
else
exception = EXCP_TLBL;
error_code = 1;
break;
case TLBRET_INVALID:
/* TLB match with no valid bit */
if (rw)
exception = EXCP_TLBS;
else
exception = EXCP_TLBL;
break;
case TLBRET_DIRTY:
/* TLB match but 'D' bit is cleared */
exception = EXCP_LTLBL;
break;
}
/* Raise exception */
env->CP0_BadVAddr = address;
env->CP0_Context = (env->CP0_Context & ~0x007fffff) |
((address >> 9) & 0x007ffff0);
env->CP0_EntryHi =
(env->CP0_EntryHi & 0xFF) | (address & (TARGET_PAGE_MASK << 1));
#if defined(TARGET_MIPS64)
env->CP0_EntryHi &= env->SEGMask;
env->CP0_XContext = (env->CP0_XContext & ((~0ULL) << (env->SEGBITS - 7))) |
((address & 0xC00000000000ULL) >> (55 - env->SEGBITS)) |
((address & ((1ULL << env->SEGBITS) - 1) & 0xFFFFFFFFFFFFE000ULL) >> 9);
#endif
env->exception_index = exception;
env->error_code = error_code;
}
target_phys_addr_t cpu_get_phys_page_debug(CPUState *env, target_ulong addr)
{
#if defined(CONFIG_USER_ONLY)
return addr;
#else
target_phys_addr_t phys_addr;
int prot;
if (get_physical_address(env, &phys_addr, &prot, addr, 0, ACCESS_INT) != 0)
return -1;
return phys_addr;
#endif
}
int cpu_mips_handle_mmu_fault (CPUState *env, target_ulong address, int rw,
int mmu_idx, int is_softmmu)
{
#if !defined(CONFIG_USER_ONLY)
target_phys_addr_t physical;
int prot;
#endif
int access_type;
int ret = 0;
#if 0
log_cpu_state(env, 0);
#endif
qemu_log("%s pc " TARGET_FMT_lx " ad " TARGET_FMT_lx " rw %d mmu_idx %d smmu %d\n",
__func__, env->active_tc.PC, address, rw, mmu_idx, is_softmmu);
rw &= 1;
/* data access */
/* XXX: put correct access by using cpu_restore_state()
correctly */
access_type = ACCESS_INT;
#if defined(CONFIG_USER_ONLY)
ret = TLBRET_NOMATCH;
#else
ret = get_physical_address(env, &physical, &prot,
address, rw, access_type);
qemu_log("%s address=" TARGET_FMT_lx " ret %d physical " TARGET_FMT_plx " prot %d\n",
__func__, address, ret, physical, prot);
if (ret == TLBRET_MATCH) {
ret = tlb_set_page(env, address & TARGET_PAGE_MASK,
physical & TARGET_PAGE_MASK, prot,
mmu_idx, is_softmmu);
} else if (ret < 0)
#endif
{
raise_mmu_exception(env, address, rw, ret);
ret = 1;
}
return ret;
}
#if !defined(CONFIG_USER_ONLY)
target_phys_addr_t do_translate_address(CPUState *env, target_ulong address, int rw)
{
target_phys_addr_t physical;
int prot;
int access_type;
int ret = 0;
rw &= 1;
/* data access */
access_type = ACCESS_INT;
ret = get_physical_address(env, &physical, &prot,
address, rw, access_type);
if (ret != TLBRET_MATCH) {
raise_mmu_exception(env, address, rw, ret);
cpu_loop_exit();
}
return physical;
}
#endif
static const char * const excp_names[EXCP_LAST + 1] = {
[EXCP_RESET] = "reset",
[EXCP_SRESET] = "soft reset",
[EXCP_DSS] = "debug single step",
[EXCP_DINT] = "debug interrupt",
[EXCP_NMI] = "non-maskable interrupt",
[EXCP_MCHECK] = "machine check",
[EXCP_EXT_INTERRUPT] = "interrupt",
[EXCP_DFWATCH] = "deferred watchpoint",
[EXCP_DIB] = "debug instruction breakpoint",
[EXCP_IWATCH] = "instruction fetch watchpoint",
[EXCP_AdEL] = "address error load",
[EXCP_AdES] = "address error store",
[EXCP_TLBF] = "TLB refill",
[EXCP_IBE] = "instruction bus error",
[EXCP_DBp] = "debug breakpoint",
[EXCP_SYSCALL] = "syscall",
[EXCP_BREAK] = "break",
[EXCP_CpU] = "coprocessor unusable",
[EXCP_RI] = "reserved instruction",
[EXCP_OVERFLOW] = "arithmetic overflow",
[EXCP_TRAP] = "trap",
[EXCP_FPE] = "floating point",
[EXCP_DDBS] = "debug data break store",
[EXCP_DWATCH] = "data watchpoint",
[EXCP_LTLBL] = "TLB modify",
[EXCP_TLBL] = "TLB load",
[EXCP_TLBS] = "TLB store",
[EXCP_DBE] = "data bus error",
[EXCP_DDBL] = "debug data break load",
[EXCP_THREAD] = "thread",
[EXCP_MDMX] = "MDMX",
[EXCP_C2E] = "precise coprocessor 2",
[EXCP_CACHE] = "cache error",
};
#if !defined(CONFIG_USER_ONLY)
static target_ulong exception_resume_pc (CPUState *env)
{
target_ulong bad_pc;
target_ulong isa_mode;
isa_mode = !!(env->hflags & MIPS_HFLAG_M16);
bad_pc = env->active_tc.PC | isa_mode;
if (env->hflags & MIPS_HFLAG_BMASK) {
/* If the exception was raised from a delay slot, come back to
the jump. */
bad_pc -= (env->hflags & MIPS_HFLAG_B16 ? 2 : 4);
}
return bad_pc;
}
#endif
void do_interrupt (CPUState *env)
{
#if !defined(CONFIG_USER_ONLY)
target_ulong offset;
int cause = -1;
const char *name;
if (qemu_log_enabled() && env->exception_index != EXCP_EXT_INTERRUPT) {
if (env->exception_index < 0 || env->exception_index > EXCP_LAST)
name = "unknown";
else
name = excp_names[env->exception_index];
qemu_log("%s enter: PC " TARGET_FMT_lx " EPC " TARGET_FMT_lx " %s exception\n",
__func__, env->active_tc.PC, env->CP0_EPC, name);
}
if (env->exception_index == EXCP_EXT_INTERRUPT &&
(env->hflags & MIPS_HFLAG_DM))
env->exception_index = EXCP_DINT;
offset = 0x180;
switch (env->exception_index) {
case EXCP_DSS:
env->CP0_Debug |= 1 << CP0DB_DSS;
/* Debug single step cannot be raised inside a delay slot and
resume will always occur on the next instruction
(but we assume the pc has always been updated during
code translation). */
env->CP0_DEPC = env->active_tc.PC | !!(env->hflags & MIPS_HFLAG_M16);
goto enter_debug_mode;
case EXCP_DINT:
env->CP0_Debug |= 1 << CP0DB_DINT;
goto set_DEPC;
case EXCP_DIB:
env->CP0_Debug |= 1 << CP0DB_DIB;
goto set_DEPC;
case EXCP_DBp:
env->CP0_Debug |= 1 << CP0DB_DBp;
goto set_DEPC;
case EXCP_DDBS:
env->CP0_Debug |= 1 << CP0DB_DDBS;
goto set_DEPC;
case EXCP_DDBL:
env->CP0_Debug |= 1 << CP0DB_DDBL;
set_DEPC:
env->CP0_DEPC = exception_resume_pc(env);
env->hflags &= ~MIPS_HFLAG_BMASK;
enter_debug_mode:
env->hflags |= MIPS_HFLAG_DM | MIPS_HFLAG_64 | MIPS_HFLAG_CP0;
env->hflags &= ~(MIPS_HFLAG_KSU);
/* EJTAG probe trap enable is not implemented... */
if (!(env->CP0_Status & (1 << CP0St_EXL)))
env->CP0_Cause &= ~(1 << CP0Ca_BD);
env->active_tc.PC = (int32_t)0xBFC00480;
/* Exception handlers are entered in 32-bit mode. */
env->hflags &= ~(MIPS_HFLAG_M16);
break;
case EXCP_RESET:
cpu_reset(env);
break;
case EXCP_SRESET:
env->CP0_Status |= (1 << CP0St_SR);
memset(env->CP0_WatchLo, 0, sizeof(*env->CP0_WatchLo));
goto set_error_EPC;
case EXCP_NMI:
env->CP0_Status |= (1 << CP0St_NMI);
set_error_EPC:
env->CP0_ErrorEPC = exception_resume_pc(env);
env->hflags &= ~MIPS_HFLAG_BMASK;
env->CP0_Status |= (1 << CP0St_ERL) | (1 << CP0St_BEV);
env->hflags |= MIPS_HFLAG_64 | MIPS_HFLAG_CP0;
env->hflags &= ~(MIPS_HFLAG_KSU);
if (!(env->CP0_Status & (1 << CP0St_EXL)))
env->CP0_Cause &= ~(1 << CP0Ca_BD);
env->active_tc.PC = (int32_t)0xBFC00000;
/* Exception handlers are entered in 32-bit mode. */
env->hflags &= ~(MIPS_HFLAG_M16);
break;
case EXCP_EXT_INTERRUPT:
cause = 0;
if (env->CP0_Cause & (1 << CP0Ca_IV))
offset = 0x200;
goto set_EPC;
case EXCP_LTLBL:
cause = 1;
goto set_EPC;
case EXCP_TLBL:
cause = 2;
if (env->error_code == 1 && !(env->CP0_Status & (1 << CP0St_EXL))) {
#if defined(TARGET_MIPS64)
int R = env->CP0_BadVAddr >> 62;
int UX = (env->CP0_Status & (1 << CP0St_UX)) != 0;
int SX = (env->CP0_Status & (1 << CP0St_SX)) != 0;
int KX = (env->CP0_Status & (1 << CP0St_KX)) != 0;
if ((R == 0 && UX) || (R == 1 && SX) || (R == 3 && KX))
offset = 0x080;
else
#endif
offset = 0x000;
}
goto set_EPC;
case EXCP_TLBS:
cause = 3;
if (env->error_code == 1 && !(env->CP0_Status & (1 << CP0St_EXL))) {
#if defined(TARGET_MIPS64)
int R = env->CP0_BadVAddr >> 62;
int UX = (env->CP0_Status & (1 << CP0St_UX)) != 0;
int SX = (env->CP0_Status & (1 << CP0St_SX)) != 0;
int KX = (env->CP0_Status & (1 << CP0St_KX)) != 0;
if ((R == 0 && UX) || (R == 1 && SX) || (R == 3 && KX))
offset = 0x080;
else
#endif
offset = 0x000;
}
goto set_EPC;
case EXCP_AdEL:
cause = 4;
goto set_EPC;
case EXCP_AdES:
cause = 5;
goto set_EPC;
case EXCP_IBE:
cause = 6;
goto set_EPC;
case EXCP_DBE:
cause = 7;
goto set_EPC;
case EXCP_SYSCALL:
cause = 8;
goto set_EPC;
case EXCP_BREAK:
cause = 9;
goto set_EPC;
case EXCP_RI:
cause = 10;
goto set_EPC;
case EXCP_CpU:
cause = 11;
env->CP0_Cause = (env->CP0_Cause & ~(0x3 << CP0Ca_CE)) |
(env->error_code << CP0Ca_CE);
goto set_EPC;
case EXCP_OVERFLOW:
cause = 12;
goto set_EPC;
case EXCP_TRAP:
cause = 13;
goto set_EPC;
case EXCP_FPE:
cause = 15;
goto set_EPC;
case EXCP_C2E:
cause = 18;
goto set_EPC;
case EXCP_MDMX:
cause = 22;
goto set_EPC;
case EXCP_DWATCH:
cause = 23;
/* XXX: TODO: manage defered watch exceptions */
goto set_EPC;
case EXCP_MCHECK:
cause = 24;
goto set_EPC;
case EXCP_THREAD:
cause = 25;
goto set_EPC;
case EXCP_CACHE:
cause = 30;
if (env->CP0_Status & (1 << CP0St_BEV)) {
offset = 0x100;
} else {
offset = 0x20000100;
}
set_EPC:
if (!(env->CP0_Status & (1 << CP0St_EXL))) {
env->CP0_EPC = exception_resume_pc(env);
if (env->hflags & MIPS_HFLAG_BMASK) {
env->CP0_Cause |= (1 << CP0Ca_BD);
} else {
env->CP0_Cause &= ~(1 << CP0Ca_BD);
}
env->CP0_Status |= (1 << CP0St_EXL);
env->hflags |= MIPS_HFLAG_64 | MIPS_HFLAG_CP0;
env->hflags &= ~(MIPS_HFLAG_KSU);
}
env->hflags &= ~MIPS_HFLAG_BMASK;
if (env->CP0_Status & (1 << CP0St_BEV)) {
env->active_tc.PC = (int32_t)0xBFC00200;
} else {
env->active_tc.PC = (int32_t)(env->CP0_EBase & ~0x3ff);
}
env->active_tc.PC += offset;
/* Exception handlers are entered in 32-bit mode. */
env->hflags &= ~(MIPS_HFLAG_M16);
env->CP0_Cause = (env->CP0_Cause & ~(0x1f << CP0Ca_EC)) | (cause << CP0Ca_EC);
break;
default:
qemu_log("Invalid MIPS exception %d. Exiting\n", env->exception_index);
printf("Invalid MIPS exception %d. Exiting\n", env->exception_index);
exit(1);
}
if (qemu_log_enabled() && env->exception_index != EXCP_EXT_INTERRUPT) {
qemu_log("%s: PC " TARGET_FMT_lx " EPC " TARGET_FMT_lx " cause %d\n"
" S %08x C %08x A " TARGET_FMT_lx " D " TARGET_FMT_lx "\n",
__func__, env->active_tc.PC, env->CP0_EPC, cause,
env->CP0_Status, env->CP0_Cause, env->CP0_BadVAddr,
env->CP0_DEPC);
}
#endif
env->exception_index = EXCP_NONE;
}
void r4k_invalidate_tlb (CPUState *env, int idx, int use_extra)
{
r4k_tlb_t *tlb;
target_ulong addr;
target_ulong end;
uint8_t ASID = env->CP0_EntryHi & 0xFF;
target_ulong mask;
tlb = &env->tlb->mmu.r4k.tlb[idx];
/* The qemu TLB is flushed when the ASID changes, so no need to
flush these entries again. */
if (tlb->G == 0 && tlb->ASID != ASID) {
return;
}
if (use_extra && env->tlb->tlb_in_use < MIPS_TLB_MAX) {
/* For tlbwr, we can shadow the discarded entry into
a new (fake) TLB entry, as long as the guest can not
tell that it's there. */
env->tlb->mmu.r4k.tlb[env->tlb->tlb_in_use] = *tlb;
env->tlb->tlb_in_use++;
return;
}
/* 1k pages are not supported. */
mask = tlb->PageMask | ~(TARGET_PAGE_MASK << 1);
if (tlb->V0) {
addr = tlb->VPN & ~mask;
#if defined(TARGET_MIPS64)
if (addr >= (0xFFFFFFFF80000000ULL & env->SEGMask)) {
addr |= 0x3FFFFF0000000000ULL;
}
#endif
end = addr | (mask >> 1);
while (addr < end) {
tlb_flush_page (env, addr);
addr += TARGET_PAGE_SIZE;
}
}
if (tlb->V1) {
addr = (tlb->VPN & ~mask) | ((mask >> 1) + 1);
#if defined(TARGET_MIPS64)
if (addr >= (0xFFFFFFFF80000000ULL & env->SEGMask)) {
addr |= 0x3FFFFF0000000000ULL;
}
#endif
end = addr | mask;
while (addr - 1 < end) {
tlb_flush_page (env, addr);
addr += TARGET_PAGE_SIZE;
}
}
}