MIPS target (Jocelyn Mayer)

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1464 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 461 insertions, 0 deletions

diff --git a/target-mips/helper.c b/target-mips/helper.c
new file mode 100644
index 0000000..05661bb
--- /dev/null
+++ b/target-mips/helper.c
@@ -0,0 +1,461 @@
+/*
+ *  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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "exec.h"
+
+/* MIPS32 4K MMU emulation */
+#if MIPS_USES_4K_TLB
+static int map_address (CPUState *env, target_ulong *physical, int *prot,
+                        target_ulong address, int rw, int access_type)
+{
+    tlb_t *tlb;
+    target_ulong tag;
+    uint8_t ASID;
+    int i, n;
+    int ret;
+
+    ret = -2;
+    tag = (address & 0xFFFFE000);
+    ASID = env->CP0_EntryHi & 0x000000FF;
+    for (i = 0; i < 16; i++) {
+        tlb = &env->tlb[i];
+        /* Check ASID, virtual page number & size */
+        if ((tlb->G == 1 || tlb->ASID == ASID) &&
+            tlb->VPN == tag && address < tlb->end) {
+            /* TLB match */
+            n = (address >> 12) & 1;
+            /* Check access rights */
+            if ((tlb->V[n] & 2) && (rw == 0 || (tlb->D[n] & 4))) {
+                *physical = tlb->PFN[n] | (address & 0xFFF);
+                *prot = PROT_READ;
+                if (tlb->D[n])
+                    *prot |= PROT_WRITE;
+                return 0;
+            } else if (!(tlb->V[n] & 2)) {
+                return -3;
+            } else {
+                return -4;
+            }
+        }
+    }
+
+    return ret;
+}
+#endif
+
+int get_physical_address (CPUState *env, target_ulong *physical, int *prot,
+                          target_ulong address, int rw, int access_type)
+{
+    int user_mode;
+    int ret;
+
+    /* User mode can only access useg */
+    user_mode = ((env->hflags & MIPS_HFLAG_MODE) == MIPS_HFLAG_UM) ? 1 : 0;
+#if 0
+    if (logfile) {
+        fprintf(logfile, "user mode %d h %08x\n",
+                user_mode, env->hflags);
+    }
+#endif
+    if (user_mode && address > 0x7FFFFFFFUL)
+        return -1;
+    ret = 0;
+    if (address < 0x80000000UL) {
+        if (user_mode || !(env->hflags & MIPS_HFLAG_ERL)) {
+#if MIPS_USES_4K_TLB
+            ret = map_address(env, physical, prot, address, rw);
+#else
+            *physical = address + 0x40000000UL;
+            *prot = PAGE_READ | PAGE_WRITE;
+#endif
+        } else {
+            *physical = address;
+            *prot = PAGE_READ | PAGE_WRITE;
+        }
+    } else if (address < 0xA0000000UL) {
+        /* kseg0 */
+        /* XXX: check supervisor mode */
+        *physical = address - 0x80000000UL;
+        *prot = PAGE_READ | PAGE_WRITE;
+    } else if (address < 0xC0000000UL) {
+        /* kseg1 */
+        /* XXX: check supervisor mode */
+        *physical = address - 0xA0000000UL;
+        *prot = PAGE_READ | PAGE_WRITE;
+    } else if (address < 0xE0000000UL) {
+        /* kseg2 */
+#if MIPS_USES_4K_TLB
+        ret = map_address(env, physical, prot, address, rw);
+#else
+        *physical = address;
+        *prot = PAGE_READ | PAGE_WRITE;
+#endif
+    } else {
+        /* kseg3 */
+        /* XXX: check supervisor mode */
+        /* XXX: debug segment is not emulated */
+#if MIPS_USES_4K_TLB
+        ret = map_address(env, physical, prot, address, rw);
+#else
+        *physical = address;
+        *prot = PAGE_READ | PAGE_WRITE;
+#endif
+    }
+#if 0
+    if (logfile) {
+        fprintf(logfile, "%08x %d %d => %08x %d (%d)\n", address, rw,
+                access_type, *physical, *prot, ret);
+    }
+#endif
+
+    return ret;
+}
+
+#if defined(CONFIG_USER_ONLY) 
+target_ulong cpu_get_phys_page_debug(CPUState *env, target_ulong addr)
+{
+    return addr;
+}
+#else
+target_ulong cpu_get_phys_page_debug(CPUState *env, target_ulong addr)
+{
+    target_ulong phys_addr;
+    int prot;
+
+    if (get_physical_address(env, &phys_addr, &prot, addr, 0, ACCESS_INT) != 0)
+        return -1;
+    return phys_addr;
+}
+#endif
+
+#if !defined(CONFIG_USER_ONLY) 
+
+#define MMUSUFFIX _mmu
+#define GETPC() (__builtin_return_address(0))
+
+#define SHIFT 0
+#include "softmmu_template.h"
+
+#define SHIFT 1
+#include "softmmu_template.h"
+
+#define SHIFT 2
+#include "softmmu_template.h"
+
+#define SHIFT 3
+#include "softmmu_template.h"
+
+void tlb_fill (target_ulong addr, int is_write, int is_user, void *retaddr)
+{
+    TranslationBlock *tb;
+    CPUState *saved_env;
+    unsigned long pc;
+    int ret;
+
+    /* XXX: hack to restore env in all cases, even if not called from
+       generated code */
+    saved_env = env;
+    env = cpu_single_env;
+    ret = cpu_mips_handle_mmu_fault(env, addr, is_write, is_user, 1);
+    if (ret) {
+        if (retaddr) {
+            /* now we have a real cpu fault */
+            pc = (unsigned long)retaddr;
+            tb = tb_find_pc(pc);
+            if (tb) {
+                /* the PC is inside the translated code. It means that we have
+                   a virtual CPU fault */
+                cpu_restore_state(tb, env, pc, NULL);
+            }
+        }
+        do_raise_exception_err(env->exception_index, env->error_code);
+    }
+    env = saved_env;
+}
+
+void cpu_mips_init_mmu (CPUState *env)
+{
+}
+
+#endif /* !defined(CONFIG_USER_ONLY) */
+
+int cpu_mips_handle_mmu_fault (CPUState *env, target_ulong address, int rw,
+                               int is_user, int is_softmmu)
+{
+    target_ulong physical;
+    int prot;
+    int exception = 0, error_code = 0;
+    int access_type;
+    int ret = 0;
+
+    if (logfile) {
+        cpu_dump_state(env, logfile, fprintf, 0);
+        fprintf(logfile, "%s pc %08x ad %08x rw %d is_user %d smmu %d\n",
+                __func__, env->PC, address, rw, is_user, is_softmmu);
+    }
+    /* data access */
+    /* XXX: put correct access by using cpu_restore_state()
+       correctly */
+    access_type = ACCESS_INT;
+    if (env->user_mode_only) {
+        /* user mode only emulation */
+        ret = -2;
+        goto do_fault;
+    }
+    ret = get_physical_address(env, &physical, &prot,
+                               address, rw, access_type);
+    if (logfile) {
+        fprintf(logfile, "%s address=%08x ret %d physical %08x prot %d\n",
+                __func__, address, ret, physical, prot);
+    }
+    if (ret == 0) {
+	ret = tlb_set_page(env, address & ~0xFFF, physical & ~0xFFF, prot,
+			   is_user, is_softmmu);
+    } else if (ret < 0) {
+    do_fault:
+        switch (ret) {
+        default:
+        case -1:
+            /* 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 -2:
+            /* No TLB match for a mapped address */
+            if (rw)
+                exception = EXCP_TLBS;
+            else
+                exception = EXCP_TLBL;
+            error_code = 1;
+            break;
+        case -3:
+            /* TLB match with no valid bit */
+            if (rw)
+                exception = EXCP_TLBS;
+            else
+                exception = EXCP_TLBL;
+            error_code = 0;
+            break;
+        case -4:
+            /* TLB match but 'D' bit is cleared */
+            exception = EXCP_LTLBL;
+            break;
+                
+        }
+        if (ret == -2) {
+            exception = EXCP_AdEL;
+        }
+        /* Raise exception */
+        env->CP0_BadVAddr = address;
+        env->CP0_Context =
+            (env->CP0_Context & 0x00000FFF) | (address & 0xFFFFF000);
+        env->CP0_EntryHi =
+            (env->CP0_EntryHi & 0x00000FFF) | (address & 0xFFFFF000);
+        env->exception_index = exception;
+        env->error_code = error_code;
+        ret = 1;
+    }
+
+    return ret;
+}
+
+void do_interrupt (CPUState *env)
+{
+    target_ulong pc, offset;
+    int cause = -1;
+
+    if (logfile && env->exception_index != EXCP_EXT_INTERRUPT) {
+        fprintf(logfile, "%s enter: PC %08x EPC %08x cause %d excp %d\n",
+                __func__, env->PC, env->CP0_EPC, cause, env->exception_index);
+    }
+    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->PC;
+        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;
+        goto set_DEPC;
+    set_DEPC:
+        if (env->hflags & MIPS_HFLAG_DS) {
+            /* If the exception was raised from a delay slot,
+             * come back to the jump
+             */
+            env->CP0_DEPC = env->PC - 4;
+        } else {
+            env->CP0_DEPC = env->PC;
+        }
+    enter_debug_mode:
+        env->hflags |= MIPS_HFLAG_DM;
+        /* EJTAG probe trap enable is not implemented... */
+        pc = 0xBFC00480;
+        break;
+    case EXCP_RESET:
+#if defined (MIPS_USES_R4K_TLB)
+        env->CP0_random = MIPS_TLB_NB - 1;
+#endif
+        env->CP0_Wired = 0;
+        env->CP0_Config0 = MIPS_CONFIG0;
+#if defined (MIPS_CONFIG1)
+        env->CP0_Config1 = MIPS_CONFIG1;
+#endif
+#if defined (MIPS_CONFIG2)
+        env->CP0_Config2 = MIPS_CONFIG2;
+#endif
+#if defined (MIPS_CONFIG3)
+        env->CP0_Config3 = MIPS_CONFIG3;
+#endif
+        env->CP0_WatchLo = 0;
+        env->CP0_Status = (1 << CP0St_CU0) | (1 << CP0St_BEV);
+        goto set_error_EPC;
+    case EXCP_SRESET:
+        env->CP0_Status = (1 << CP0St_CU0) | (1 << CP0St_BEV) |
+            (1 << CP0St_SR);
+        env->CP0_WatchLo = 0;
+        goto set_error_EPC;
+    case EXCP_NMI:
+        env->CP0_Status = (1 << CP0St_CU0) | (1 << CP0St_BEV) |
+            (1 << CP0St_NMI);
+    set_error_EPC:
+        env->hflags = MIPS_HFLAG_ERL;
+        if (env->hflags & MIPS_HFLAG_DS) {
+            /* If the exception was raised from a delay slot,
+             * come back to the jump
+             */
+            env->CP0_ErrorEPC = env->PC - 4;
+        } else {
+            env->CP0_ErrorEPC = env->PC;
+        }
+        pc = 0xBFC00000;
+        break;
+    case EXCP_MCHECK:
+        cause = 24;
+        goto set_EPC;
+    case EXCP_EXT_INTERRUPT:
+        cause = 0;
+        if (env->CP0_Cause & (1 << CP0Ca_IV))
+            offset = 0x200;
+        goto set_EPC;
+    case EXCP_DWATCH:
+        cause = 23;
+        /* XXX: TODO: manage defered watch exceptions */
+        goto set_EPC;
+    case EXCP_AdEL:
+    case EXCP_AdES:
+        cause = 4;
+        goto set_EPC;
+    case EXCP_TLBL:
+    case EXCP_TLBF:
+        cause = 2;
+        if (env->error_code == 1 && !(env->hflags & MIPS_HFLAG_EXL))
+            offset = 0x000;
+        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;
+        /* XXX: fill in the faulty unit number */
+        goto set_EPC;
+    case EXCP_OVERFLOW:
+        cause = 12;
+        goto set_EPC;
+    case EXCP_TRAP:
+        cause = 13;
+        goto set_EPC;
+    case EXCP_LTLBL:
+        cause = 1;
+        goto set_EPC;
+    case EXCP_TLBS:
+        cause = 3;
+    set_EPC:
+        if (env->CP0_Status & (1 << CP0St_BEV)) {
+            pc = 0xBFC00200;
+        } else {
+            pc = 0x80000000;
+        }
+        env->hflags |= MIPS_HFLAG_EXL;
+        pc += offset;
+        env->CP0_Cause = (env->CP0_Cause & ~0x7C) | (cause << 2);
+        if (env->hflags & MIPS_HFLAG_DS) {
+            /* If the exception was raised from a delay slot,
+             * come back to the jump
+             */
+            env->CP0_EPC = env->PC - 4;
+            env->CP0_Cause |= 0x80000000;
+        } else {
+            env->CP0_EPC = env->PC;
+            env->CP0_Cause &= ~0x80000000;
+        }
+        break;
+    default:
+        if (logfile) {
+            fprintf(logfile, "Invalid MIPS exception %d. Exiting\n",
+                    env->exception_index);
+        }
+        printf("Invalid MIPS exception %d. Exiting\n", env->exception_index);
+        exit(1);
+    }
+    env->PC = pc;
+    if (logfile && env->exception_index != EXCP_EXT_INTERRUPT) {
+        fprintf(logfile, "%s: PC %08x EPC %08x cause %d excp %d\n"
+                "    S %08x C %08x A %08x D %08x\n",
+                __func__, env->PC, env->CP0_EPC, cause, env->exception_index,
+                env->CP0_Status, env->CP0_Cause, env->CP0_BadVAddr,
+                env->CP0_DEPC);
+    }
+    env->exception_index = EXCP_NONE;
+}