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-rw-r--r--target/mips/tlb_helper.c1347
1 files changed, 1347 insertions, 0 deletions
diff --git a/target/mips/tlb_helper.c b/target/mips/tlb_helper.c
new file mode 100644
index 0000000000..082c17928d
--- /dev/null
+++ b/target/mips/tlb_helper.c
@@ -0,0 +1,1347 @@
+/*
+ * MIPS TLB (Translation lookaside buffer) helpers.
+ *
+ *  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 2.1 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 "qemu/osdep.h"
+
+#include "cpu.h"
+#include "internal.h"
+#include "exec/exec-all.h"
+#include "exec/cpu_ldst.h"
+#include "exec/log.h"
+#include "hw/mips/cpudevs.h"
+
+enum {
+    TLBRET_XI = -6,
+    TLBRET_RI = -5,
+    TLBRET_DIRTY = -4,
+    TLBRET_INVALID = -3,
+    TLBRET_NOMATCH = -2,
+    TLBRET_BADADDR = -1,
+    TLBRET_MATCH = 0
+};
+
+#if !defined(CONFIG_USER_ONLY)
+
+/* no MMU emulation */
+int no_mmu_map_address(CPUMIPSState *env, hwaddr *physical, int *prot,
+                       target_ulong address, int rw, int access_type)
+{
+    *physical = address;
+    *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
+    return TLBRET_MATCH;
+}
+
+/* fixed mapping MMU emulation */
+int fixed_mmu_map_address(CPUMIPSState *env, hwaddr *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 | PAGE_EXEC;
+    return TLBRET_MATCH;
+}
+
+/* MIPS32/MIPS64 R4000-style MMU emulation */
+int r4k_map_address(CPUMIPSState *env, hwaddr *physical, int *prot,
+                    target_ulong address, int rw, int access_type)
+{
+    uint16_t ASID = env->CP0_EntryHi & env->CP0_EntryHi_ASID_mask;
+    uint32_t MMID = env->CP0_MemoryMapID;
+    bool mi = !!((env->CP0_Config5 >> CP0C5_MI) & 1);
+    uint32_t tlb_mmid;
+    int i;
+
+    MMID = mi ? MMID : (uint32_t) ASID;
+
+    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/MMID, virtual page number & size */
+        tlb_mmid = mi ? tlb->MMID : (uint32_t) tlb->ASID;
+        if ((tlb->G == 1 || tlb_mmid == MMID) && VPN == tag && !tlb->EHINV) {
+            /* TLB match */
+            int n = !!(address & mask & ~(mask >> 1));
+            /* Check access rights */
+            if (!(n ? tlb->V1 : tlb->V0)) {
+                return TLBRET_INVALID;
+            }
+            if (rw == MMU_INST_FETCH && (n ? tlb->XI1 : tlb->XI0)) {
+                return TLBRET_XI;
+            }
+            if (rw == MMU_DATA_LOAD && (n ? tlb->RI1 : tlb->RI0)) {
+                return TLBRET_RI;
+            }
+            if (rw != MMU_DATA_STORE || (n ? tlb->D1 : tlb->D0)) {
+                *physical = tlb->PFN[n] | (address & (mask >> 1));
+                *prot = PAGE_READ;
+                if (n ? tlb->D1 : tlb->D0) {
+                    *prot |= PAGE_WRITE;
+                }
+                if (!(n ? tlb->XI1 : tlb->XI0)) {
+                    *prot |= PAGE_EXEC;
+                }
+                return TLBRET_MATCH;
+            }
+            return TLBRET_DIRTY;
+        }
+    }
+    return TLBRET_NOMATCH;
+}
+
+static void no_mmu_init(CPUMIPSState *env, const mips_def_t *def)
+{
+    env->tlb->nb_tlb = 1;
+    env->tlb->map_address = &no_mmu_map_address;
+}
+
+static void fixed_mmu_init(CPUMIPSState *env, const mips_def_t *def)
+{
+    env->tlb->nb_tlb = 1;
+    env->tlb->map_address = &fixed_mmu_map_address;
+}
+
+static void r4k_mmu_init(CPUMIPSState *env, const mips_def_t *def)
+{
+    env->tlb->nb_tlb = 1 + ((def->CP0_Config1 >> CP0C1_MMU) & 63);
+    env->tlb->map_address = &r4k_map_address;
+    env->tlb->helper_tlbwi = r4k_helper_tlbwi;
+    env->tlb->helper_tlbwr = r4k_helper_tlbwr;
+    env->tlb->helper_tlbp = r4k_helper_tlbp;
+    env->tlb->helper_tlbr = r4k_helper_tlbr;
+    env->tlb->helper_tlbinv = r4k_helper_tlbinv;
+    env->tlb->helper_tlbinvf = r4k_helper_tlbinvf;
+}
+
+void mmu_init(CPUMIPSState *env, const mips_def_t *def)
+{
+    env->tlb = g_malloc0(sizeof(CPUMIPSTLBContext));
+
+    switch (def->mmu_type) {
+    case MMU_TYPE_NONE:
+        no_mmu_init(env, def);
+        break;
+    case MMU_TYPE_R4000:
+        r4k_mmu_init(env, def);
+        break;
+    case MMU_TYPE_FMT:
+        fixed_mmu_init(env, def);
+        break;
+    case MMU_TYPE_R3000:
+    case MMU_TYPE_R6000:
+    case MMU_TYPE_R8000:
+    default:
+        cpu_abort(env_cpu(env), "MMU type not supported\n");
+    }
+}
+
+static int is_seg_am_mapped(unsigned int am, bool eu, int mmu_idx)
+{
+    /*
+     * Interpret access control mode and mmu_idx.
+     *           AdE?     TLB?
+     *      AM  K S U E  K S U E
+     * UK    0  0 1 1 0  0 - - 0
+     * MK    1  0 1 1 0  1 - - !eu
+     * MSK   2  0 0 1 0  1 1 - !eu
+     * MUSK  3  0 0 0 0  1 1 1 !eu
+     * MUSUK 4  0 0 0 0  0 1 1 0
+     * USK   5  0 0 1 0  0 0 - 0
+     * -     6  - - - -  - - - -
+     * UUSK  7  0 0 0 0  0 0 0 0
+     */
+    int32_t adetlb_mask;
+
+    switch (mmu_idx) {
+    case 3: /* ERL */
+        /* If EU is set, always unmapped */
+        if (eu) {
+            return 0;
+        }
+        /* fall through */
+    case MIPS_HFLAG_KM:
+        /* Never AdE, TLB mapped if AM={1,2,3} */
+        adetlb_mask = 0x70000000;
+        goto check_tlb;
+
+    case MIPS_HFLAG_SM:
+        /* AdE if AM={0,1}, TLB mapped if AM={2,3,4} */
+        adetlb_mask = 0xc0380000;
+        goto check_ade;
+
+    case MIPS_HFLAG_UM:
+        /* AdE if AM={0,1,2,5}, TLB mapped if AM={3,4} */
+        adetlb_mask = 0xe4180000;
+        /* fall through */
+    check_ade:
+        /* does this AM cause AdE in current execution mode */
+        if ((adetlb_mask << am) < 0) {
+            return TLBRET_BADADDR;
+        }
+        adetlb_mask <<= 8;
+        /* fall through */
+    check_tlb:
+        /* is this AM mapped in current execution mode */
+        return ((adetlb_mask << am) < 0);
+    default:
+        assert(0);
+        return TLBRET_BADADDR;
+    };
+}
+
+static int get_seg_physical_address(CPUMIPSState *env, hwaddr *physical,
+                                    int *prot, target_ulong real_address,
+                                    int rw, int access_type, int mmu_idx,
+                                    unsigned int am, bool eu,
+                                    target_ulong segmask,
+                                    hwaddr physical_base)
+{
+    int mapped = is_seg_am_mapped(am, eu, mmu_idx);
+
+    if (mapped < 0) {
+        /* is_seg_am_mapped can report TLBRET_BADADDR */
+        return mapped;
+    } else if (mapped) {
+        /* The segment is TLB mapped */
+        return env->tlb->map_address(env, physical, prot, real_address, rw,
+                                     access_type);
+    } else {
+        /* The segment is unmapped */
+        *physical = physical_base | (real_address & segmask);
+        *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
+        return TLBRET_MATCH;
+    }
+}
+
+static int get_segctl_physical_address(CPUMIPSState *env, hwaddr *physical,
+                                       int *prot, target_ulong real_address,
+                                       int rw, int access_type, int mmu_idx,
+                                       uint16_t segctl, target_ulong segmask)
+{
+    unsigned int am = (segctl & CP0SC_AM_MASK) >> CP0SC_AM;
+    bool eu = (segctl >> CP0SC_EU) & 1;
+    hwaddr pa = ((hwaddr)segctl & CP0SC_PA_MASK) << 20;
+
+    return get_seg_physical_address(env, physical, prot, real_address, rw,
+                                    access_type, mmu_idx, am, eu, segmask,
+                                    pa & ~(hwaddr)segmask);
+}
+
+static int get_physical_address(CPUMIPSState *env, hwaddr *physical,
+                                int *prot, target_ulong real_address,
+                                int rw, int access_type, int mmu_idx)
+{
+    /* User mode can only access useg/xuseg */
+#if defined(TARGET_MIPS64)
+    int user_mode = mmu_idx == MIPS_HFLAG_UM;
+    int supervisor_mode = mmu_idx == MIPS_HFLAG_SM;
+    int kernel_mode = !user_mode && !supervisor_mode;
+    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;
+    /* effective address (modified for KVM T&E kernel segments) */
+    target_ulong address = real_address;
+
+#define USEG_LIMIT      ((target_ulong)(int32_t)0x7FFFFFFFUL)
+#define KSEG0_BASE      ((target_ulong)(int32_t)0x80000000UL)
+#define KSEG1_BASE      ((target_ulong)(int32_t)0xA0000000UL)
+#define KSEG2_BASE      ((target_ulong)(int32_t)0xC0000000UL)
+#define KSEG3_BASE      ((target_ulong)(int32_t)0xE0000000UL)
+
+#define KVM_KSEG0_BASE  ((target_ulong)(int32_t)0x40000000UL)
+#define KVM_KSEG2_BASE  ((target_ulong)(int32_t)0x60000000UL)
+
+    if (mips_um_ksegs_enabled()) {
+        /* KVM T&E adds guest kernel segments in useg */
+        if (real_address >= KVM_KSEG0_BASE) {
+            if (real_address < KVM_KSEG2_BASE) {
+                /* kseg0 */
+                address += KSEG0_BASE - KVM_KSEG0_BASE;
+            } else if (real_address <= USEG_LIMIT) {
+                /* kseg2/3 */
+                address += KSEG2_BASE - KVM_KSEG2_BASE;
+            }
+        }
+    }
+
+    if (address <= USEG_LIMIT) {
+        /* useg */
+        uint16_t segctl;
+
+        if (address >= 0x40000000UL) {
+            segctl = env->CP0_SegCtl2;
+        } else {
+            segctl = env->CP0_SegCtl2 >> 16;
+        }
+        ret = get_segctl_physical_address(env, physical, prot,
+                                          real_address, rw, access_type,
+                                          mmu_idx, segctl, 0x3FFFFFFF);
+#if defined(TARGET_MIPS64)
+    } else if (address < 0x4000000000000000ULL) {
+        /* xuseg */
+        if (UX && address <= (0x3FFFFFFFFFFFFFFFULL & env->SEGMask)) {
+            ret = env->tlb->map_address(env, physical, prot,
+                                        real_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,
+                                        real_address, rw, access_type);
+        } else {
+            ret = TLBRET_BADADDR;
+        }
+    } else if (address < 0xC000000000000000ULL) {
+        /* xkphys */
+        if ((address & 0x07FFFFFFFFFFFFFFULL) <= env->PAMask) {
+            /* KX/SX/UX bit to check for each xkphys EVA access mode */
+            static const uint8_t am_ksux[8] = {
+                [CP0SC_AM_UK]    = (1u << CP0St_KX),
+                [CP0SC_AM_MK]    = (1u << CP0St_KX),
+                [CP0SC_AM_MSK]   = (1u << CP0St_SX),
+                [CP0SC_AM_MUSK]  = (1u << CP0St_UX),
+                [CP0SC_AM_MUSUK] = (1u << CP0St_UX),
+                [CP0SC_AM_USK]   = (1u << CP0St_SX),
+                [6]              = (1u << CP0St_KX),
+                [CP0SC_AM_UUSK]  = (1u << CP0St_UX),
+            };
+            unsigned int am = CP0SC_AM_UK;
+            unsigned int xr = (env->CP0_SegCtl2 & CP0SC2_XR_MASK) >> CP0SC2_XR;
+
+            if (xr & (1 << ((address >> 59) & 0x7))) {
+                am = (env->CP0_SegCtl1 & CP0SC1_XAM_MASK) >> CP0SC1_XAM;
+            }
+            /* Does CP0_Status.KX/SX/UX permit the access mode (am) */
+            if (env->CP0_Status & am_ksux[am]) {
+                ret = get_seg_physical_address(env, physical, prot,
+                                               real_address, rw, access_type,
+                                               mmu_idx, am, false, env->PAMask,
+                                               0);
+            } else {
+                ret = TLBRET_BADADDR;
+            }
+        } 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,
+                                        real_address, rw, access_type);
+        } else {
+            ret = TLBRET_BADADDR;
+        }
+#endif
+    } else if (address < KSEG1_BASE) {
+        /* kseg0 */
+        ret = get_segctl_physical_address(env, physical, prot, real_address, rw,
+                                          access_type, mmu_idx,
+                                          env->CP0_SegCtl1 >> 16, 0x1FFFFFFF);
+    } else if (address < KSEG2_BASE) {
+        /* kseg1 */
+        ret = get_segctl_physical_address(env, physical, prot, real_address, rw,
+                                          access_type, mmu_idx,
+                                          env->CP0_SegCtl1, 0x1FFFFFFF);
+    } else if (address < KSEG3_BASE) {
+        /* sseg (kseg2) */
+        ret = get_segctl_physical_address(env, physical, prot, real_address, rw,
+                                          access_type, mmu_idx,
+                                          env->CP0_SegCtl0 >> 16, 0x1FFFFFFF);
+    } else {
+        /*
+         * kseg3
+         * XXX: debug segment is not emulated
+         */
+        ret = get_segctl_physical_address(env, physical, prot, real_address, rw,
+                                          access_type, mmu_idx,
+                                          env->CP0_SegCtl0, 0x1FFFFFFF);
+    }
+    return ret;
+}
+
+void cpu_mips_tlb_flush(CPUMIPSState *env)
+{
+    /* Flush qemu's TLB and discard all shadowed entries.  */
+    tlb_flush(env_cpu(env));
+    env->tlb->tlb_in_use = env->tlb->nb_tlb;
+}
+
+#endif /* !CONFIG_USER_ONLY */
+
+static void raise_mmu_exception(CPUMIPSState *env, target_ulong address,
+                                int rw, int tlb_error)
+{
+    CPUState *cs = env_cpu(env);
+    int exception = 0, error_code = 0;
+
+    if (rw == MMU_INST_FETCH) {
+        error_code |= EXCP_INST_NOTAVAIL;
+    }
+
+    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 == MMU_DATA_STORE) {
+            exception = EXCP_AdES;
+        } else {
+            exception = EXCP_AdEL;
+        }
+        break;
+    case TLBRET_NOMATCH:
+        /* No TLB match for a mapped address */
+        if (rw == MMU_DATA_STORE) {
+            exception = EXCP_TLBS;
+        } else {
+            exception = EXCP_TLBL;
+        }
+        error_code |= EXCP_TLB_NOMATCH;
+        break;
+    case TLBRET_INVALID:
+        /* TLB match with no valid bit */
+        if (rw == MMU_DATA_STORE) {
+            exception = EXCP_TLBS;
+        } else {
+            exception = EXCP_TLBL;
+        }
+        break;
+    case TLBRET_DIRTY:
+        /* TLB match but 'D' bit is cleared */
+        exception = EXCP_LTLBL;
+        break;
+    case TLBRET_XI:
+        /* Execute-Inhibit Exception */
+        if (env->CP0_PageGrain & (1 << CP0PG_IEC)) {
+            exception = EXCP_TLBXI;
+        } else {
+            exception = EXCP_TLBL;
+        }
+        break;
+    case TLBRET_RI:
+        /* Read-Inhibit Exception */
+        if (env->CP0_PageGrain & (1 << CP0PG_IEC)) {
+            exception = EXCP_TLBRI;
+        } else {
+            exception = EXCP_TLBL;
+        }
+        break;
+    }
+    /* Raise exception */
+    if (!(env->hflags & MIPS_HFLAG_DM)) {
+        env->CP0_BadVAddr = address;
+    }
+    env->CP0_Context = (env->CP0_Context & ~0x007fffff) |
+                       ((address >> 9) & 0x007ffff0);
+    env->CP0_EntryHi = (env->CP0_EntryHi & env->CP0_EntryHi_ASID_mask) |
+                       (env->CP0_EntryHi & (1 << CP0EnHi_EHINV)) |
+                       (address & (TARGET_PAGE_MASK << 1));
+#if defined(TARGET_MIPS64)
+    env->CP0_EntryHi &= env->SEGMask;
+    env->CP0_XContext =
+        (env->CP0_XContext & ((~0ULL) << (env->SEGBITS - 7))) | /* PTEBase */
+        (extract64(address, 62, 2) << (env->SEGBITS - 9)) |     /* R       */
+        (extract64(address, 13, env->SEGBITS - 13) << 4);       /* BadVPN2 */
+#endif
+    cs->exception_index = exception;
+    env->error_code = error_code;
+}
+
+#if !defined(CONFIG_USER_ONLY)
+
+hwaddr mips_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
+{
+    MIPSCPU *cpu = MIPS_CPU(cs);
+    CPUMIPSState *env = &cpu->env;
+    hwaddr phys_addr;
+    int prot;
+
+    if (get_physical_address(env, &phys_addr, &prot, addr, 0, ACCESS_INT,
+                             cpu_mmu_index(env, false)) != 0) {
+        return -1;
+    }
+    return phys_addr;
+}
+
+#if !defined(TARGET_MIPS64)
+
+/*
+ * Perform hardware page table walk
+ *
+ * Memory accesses are performed using the KERNEL privilege level.
+ * Synchronous exceptions detected on memory accesses cause a silent exit
+ * from page table walking, resulting in a TLB or XTLB Refill exception.
+ *
+ * Implementations are not required to support page table walk memory
+ * accesses from mapped memory regions. When an unsupported access is
+ * attempted, a silent exit is taken, resulting in a TLB or XTLB Refill
+ * exception.
+ *
+ * Note that if an exception is caused by AddressTranslation or LoadMemory
+ * functions, the exception is not taken, a silent exit is taken,
+ * resulting in a TLB or XTLB Refill exception.
+ */
+
+static bool get_pte(CPUMIPSState *env, uint64_t vaddr, int entry_size,
+        uint64_t *pte)
+{
+    if ((vaddr & ((entry_size >> 3) - 1)) != 0) {
+        return false;
+    }
+    if (entry_size == 64) {
+        *pte = cpu_ldq_code(env, vaddr);
+    } else {
+        *pte = cpu_ldl_code(env, vaddr);
+    }
+    return true;
+}
+
+static uint64_t get_tlb_entry_layout(CPUMIPSState *env, uint64_t entry,
+        int entry_size, int ptei)
+{
+    uint64_t result = entry;
+    uint64_t rixi;
+    if (ptei > entry_size) {
+        ptei -= 32;
+    }
+    result >>= (ptei - 2);
+    rixi = result & 3;
+    result >>= 2;
+    result |= rixi << CP0EnLo_XI;
+    return result;
+}
+
+static int walk_directory(CPUMIPSState *env, uint64_t *vaddr,
+        int directory_index, bool *huge_page, bool *hgpg_directory_hit,
+        uint64_t *pw_entrylo0, uint64_t *pw_entrylo1)
+{
+    int dph = (env->CP0_PWCtl >> CP0PC_DPH) & 0x1;
+    int psn = (env->CP0_PWCtl >> CP0PC_PSN) & 0x3F;
+    int hugepg = (env->CP0_PWCtl >> CP0PC_HUGEPG) & 0x1;
+    int pf_ptew = (env->CP0_PWField >> CP0PF_PTEW) & 0x3F;
+    int ptew = (env->CP0_PWSize >> CP0PS_PTEW) & 0x3F;
+    int native_shift = (((env->CP0_PWSize >> CP0PS_PS) & 1) == 0) ? 2 : 3;
+    int directory_shift = (ptew > 1) ? -1 :
+            (hugepg && (ptew == 1)) ? native_shift + 1 : native_shift;
+    int leaf_shift = (ptew > 1) ? -1 :
+            (ptew == 1) ? native_shift + 1 : native_shift;
+    uint32_t direntry_size = 1 << (directory_shift + 3);
+    uint32_t leafentry_size = 1 << (leaf_shift + 3);
+    uint64_t entry;
+    uint64_t paddr;
+    int prot;
+    uint64_t lsb = 0;
+    uint64_t w = 0;
+
+    if (get_physical_address(env, &paddr, &prot, *vaddr, MMU_DATA_LOAD,
+                             ACCESS_INT, cpu_mmu_index(env, false)) !=
+                             TLBRET_MATCH) {
+        /* wrong base address */
+        return 0;
+    }
+    if (!get_pte(env, *vaddr, direntry_size, &entry)) {
+        return 0;
+    }
+
+    if ((entry & (1 << psn)) && hugepg) {
+        *huge_page = true;
+        *hgpg_directory_hit = true;
+        entry = get_tlb_entry_layout(env, entry, leafentry_size, pf_ptew);
+        w = directory_index - 1;
+        if (directory_index & 0x1) {
+            /* Generate adjacent page from same PTE for odd TLB page */
+            lsb = (1 << w) >> 6;
+            *pw_entrylo0 = entry & ~lsb; /* even page */
+            *pw_entrylo1 = entry | lsb; /* odd page */
+        } else if (dph) {
+            int oddpagebit = 1 << leaf_shift;
+            uint64_t vaddr2 = *vaddr ^ oddpagebit;
+            if (*vaddr & oddpagebit) {
+                *pw_entrylo1 = entry;
+            } else {
+                *pw_entrylo0 = entry;
+            }
+            if (get_physical_address(env, &paddr, &prot, vaddr2, MMU_DATA_LOAD,
+                                     ACCESS_INT, cpu_mmu_index(env, false)) !=
+                                     TLBRET_MATCH) {
+                return 0;
+            }
+            if (!get_pte(env, vaddr2, leafentry_size, &entry)) {
+                return 0;
+            }
+            entry = get_tlb_entry_layout(env, entry, leafentry_size, pf_ptew);
+            if (*vaddr & oddpagebit) {
+                *pw_entrylo0 = entry;
+            } else {
+                *pw_entrylo1 = entry;
+            }
+        } else {
+            return 0;
+        }
+        return 1;
+    } else {
+        *vaddr = entry;
+        return 2;
+    }
+}
+
+static bool page_table_walk_refill(CPUMIPSState *env, vaddr address, int rw,
+        int mmu_idx)
+{
+    int gdw = (env->CP0_PWSize >> CP0PS_GDW) & 0x3F;
+    int udw = (env->CP0_PWSize >> CP0PS_UDW) & 0x3F;
+    int mdw = (env->CP0_PWSize >> CP0PS_MDW) & 0x3F;
+    int ptw = (env->CP0_PWSize >> CP0PS_PTW) & 0x3F;
+    int ptew = (env->CP0_PWSize >> CP0PS_PTEW) & 0x3F;
+
+    /* Initial values */
+    bool huge_page = false;
+    bool hgpg_bdhit = false;
+    bool hgpg_gdhit = false;
+    bool hgpg_udhit = false;
+    bool hgpg_mdhit = false;
+
+    int32_t pw_pagemask = 0;
+    target_ulong pw_entryhi = 0;
+    uint64_t pw_entrylo0 = 0;
+    uint64_t pw_entrylo1 = 0;
+
+    /* Native pointer size */
+    /*For the 32-bit architectures, this bit is fixed to 0.*/
+    int native_shift = (((env->CP0_PWSize >> CP0PS_PS) & 1) == 0) ? 2 : 3;
+
+    /* Indices from PWField */
+    int pf_gdw = (env->CP0_PWField >> CP0PF_GDW) & 0x3F;
+    int pf_udw = (env->CP0_PWField >> CP0PF_UDW) & 0x3F;
+    int pf_mdw = (env->CP0_PWField >> CP0PF_MDW) & 0x3F;
+    int pf_ptw = (env->CP0_PWField >> CP0PF_PTW) & 0x3F;
+    int pf_ptew = (env->CP0_PWField >> CP0PF_PTEW) & 0x3F;
+
+    /* Indices computed from faulting address */
+    int gindex = (address >> pf_gdw) & ((1 << gdw) - 1);
+    int uindex = (address >> pf_udw) & ((1 << udw) - 1);
+    int mindex = (address >> pf_mdw) & ((1 << mdw) - 1);
+    int ptindex = (address >> pf_ptw) & ((1 << ptw) - 1);
+
+    /* Other HTW configs */
+    int hugepg = (env->CP0_PWCtl >> CP0PC_HUGEPG) & 0x1;
+
+    /* HTW Shift values (depend on entry size) */
+    int directory_shift = (ptew > 1) ? -1 :
+            (hugepg && (ptew == 1)) ? native_shift + 1 : native_shift;
+    int leaf_shift = (ptew > 1) ? -1 :
+            (ptew == 1) ? native_shift + 1 : native_shift;
+
+    /* Offsets into tables */
+    int goffset = gindex << directory_shift;
+    int uoffset = uindex << directory_shift;
+    int moffset = mindex << directory_shift;
+    int ptoffset0 = (ptindex >> 1) << (leaf_shift + 1);
+    int ptoffset1 = ptoffset0 | (1 << (leaf_shift));
+
+    uint32_t leafentry_size = 1 << (leaf_shift + 3);
+
+    /* Starting address - Page Table Base */
+    uint64_t vaddr = env->CP0_PWBase;
+
+    uint64_t dir_entry;
+    uint64_t paddr;
+    int prot;
+    int m;
+
+    if (!(env->CP0_Config3 & (1 << CP0C3_PW))) {
+        /* walker is unimplemented */
+        return false;
+    }
+    if (!(env->CP0_PWCtl & (1 << CP0PC_PWEN))) {
+        /* walker is disabled */
+        return false;
+    }
+    if (!(gdw > 0 || udw > 0 || mdw > 0)) {
+        /* no structure to walk */
+        return false;
+    }
+    if ((directory_shift == -1) || (leaf_shift == -1)) {
+        return false;
+    }
+
+    /* Global Directory */
+    if (gdw > 0) {
+        vaddr |= goffset;
+        switch (walk_directory(env, &vaddr, pf_gdw, &huge_page, &hgpg_gdhit,
+                               &pw_entrylo0, &pw_entrylo1))
+        {
+        case 0:
+            return false;
+        case 1:
+            goto refill;
+        case 2:
+        default:
+            break;
+        }
+    }
+
+    /* Upper directory */
+    if (udw > 0) {
+        vaddr |= uoffset;
+        switch (walk_directory(env, &vaddr, pf_udw, &huge_page, &hgpg_udhit,
+                               &pw_entrylo0, &pw_entrylo1))
+        {
+        case 0:
+            return false;
+        case 1:
+            goto refill;
+        case 2:
+        default:
+            break;
+        }
+    }
+
+    /* Middle directory */
+    if (mdw > 0) {
+        vaddr |= moffset;
+        switch (walk_directory(env, &vaddr, pf_mdw, &huge_page, &hgpg_mdhit,
+                               &pw_entrylo0, &pw_entrylo1))
+        {
+        case 0:
+            return false;
+        case 1:
+            goto refill;
+        case 2:
+        default:
+            break;
+        }
+    }
+
+    /* Leaf Level Page Table - First half of PTE pair */
+    vaddr |= ptoffset0;
+    if (get_physical_address(env, &paddr, &prot, vaddr, MMU_DATA_LOAD,
+                             ACCESS_INT, cpu_mmu_index(env, false)) !=
+                             TLBRET_MATCH) {
+        return false;
+    }
+    if (!get_pte(env, vaddr, leafentry_size, &dir_entry)) {
+        return false;
+    }
+    dir_entry = get_tlb_entry_layout(env, dir_entry, leafentry_size, pf_ptew);
+    pw_entrylo0 = dir_entry;
+
+    /* Leaf Level Page Table - Second half of PTE pair */
+    vaddr |= ptoffset1;
+    if (get_physical_address(env, &paddr, &prot, vaddr, MMU_DATA_LOAD,
+                             ACCESS_INT, cpu_mmu_index(env, false)) !=
+                             TLBRET_MATCH) {
+        return false;
+    }
+    if (!get_pte(env, vaddr, leafentry_size, &dir_entry)) {
+        return false;
+    }
+    dir_entry = get_tlb_entry_layout(env, dir_entry, leafentry_size, pf_ptew);
+    pw_entrylo1 = dir_entry;
+
+refill:
+
+    m = (1 << pf_ptw) - 1;
+
+    if (huge_page) {
+        switch (hgpg_bdhit << 3 | hgpg_gdhit << 2 | hgpg_udhit << 1 |
+                hgpg_mdhit)
+        {
+        case 4:
+            m = (1 << pf_gdw) - 1;
+            if (pf_gdw & 1) {
+                m >>= 1;
+            }
+            break;
+        case 2:
+            m = (1 << pf_udw) - 1;
+            if (pf_udw & 1) {
+                m >>= 1;
+            }
+            break;
+        case 1:
+            m = (1 << pf_mdw) - 1;
+            if (pf_mdw & 1) {
+                m >>= 1;
+            }
+            break;
+        }
+    }
+    pw_pagemask = m >> TARGET_PAGE_BITS_MIN;
+    update_pagemask(env, pw_pagemask << CP0PM_MASK, &pw_pagemask);
+    pw_entryhi = (address & ~0x1fff) | (env->CP0_EntryHi & 0xFF);
+    {
+        target_ulong tmp_entryhi = env->CP0_EntryHi;
+        int32_t tmp_pagemask = env->CP0_PageMask;
+        uint64_t tmp_entrylo0 = env->CP0_EntryLo0;
+        uint64_t tmp_entrylo1 = env->CP0_EntryLo1;
+
+        env->CP0_EntryHi = pw_entryhi;
+        env->CP0_PageMask = pw_pagemask;
+        env->CP0_EntryLo0 = pw_entrylo0;
+        env->CP0_EntryLo1 = pw_entrylo1;
+
+        /*
+         * The hardware page walker inserts a page into the TLB in a manner
+         * identical to a TLBWR instruction as executed by the software refill
+         * handler.
+         */
+        r4k_helper_tlbwr(env);
+
+        env->CP0_EntryHi = tmp_entryhi;
+        env->CP0_PageMask = tmp_pagemask;
+        env->CP0_EntryLo0 = tmp_entrylo0;
+        env->CP0_EntryLo1 = tmp_entrylo1;
+    }
+    return true;
+}
+#endif
+#endif /* !CONFIG_USER_ONLY */
+
+bool mips_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
+                       MMUAccessType access_type, int mmu_idx,
+                       bool probe, uintptr_t retaddr)
+{
+    MIPSCPU *cpu = MIPS_CPU(cs);
+    CPUMIPSState *env = &cpu->env;
+#if !defined(CONFIG_USER_ONLY)
+    hwaddr physical;
+    int prot;
+    int mips_access_type;
+#endif
+    int ret = TLBRET_BADADDR;
+
+    /* data access */
+#if !defined(CONFIG_USER_ONLY)
+    /* XXX: put correct access by using cpu_restore_state() correctly */
+    mips_access_type = ACCESS_INT;
+    ret = get_physical_address(env, &physical, &prot, address,
+                               access_type, mips_access_type, mmu_idx);
+    switch (ret) {
+    case TLBRET_MATCH:
+        qemu_log_mask(CPU_LOG_MMU,
+                      "%s address=%" VADDR_PRIx " physical " TARGET_FMT_plx
+                      " prot %d\n", __func__, address, physical, prot);
+        break;
+    default:
+        qemu_log_mask(CPU_LOG_MMU,
+                      "%s address=%" VADDR_PRIx " ret %d\n", __func__, address,
+                      ret);
+        break;
+    }
+    if (ret == TLBRET_MATCH) {
+        tlb_set_page(cs, address & TARGET_PAGE_MASK,
+                     physical & TARGET_PAGE_MASK, prot,
+                     mmu_idx, TARGET_PAGE_SIZE);
+        return true;
+    }
+#if !defined(TARGET_MIPS64)
+    if ((ret == TLBRET_NOMATCH) && (env->tlb->nb_tlb > 1)) {
+        /*
+         * Memory reads during hardware page table walking are performed
+         * as if they were kernel-mode load instructions.
+         */
+        int mode = (env->hflags & MIPS_HFLAG_KSU);
+        bool ret_walker;
+        env->hflags &= ~MIPS_HFLAG_KSU;
+        ret_walker = page_table_walk_refill(env, address, access_type, mmu_idx);
+        env->hflags |= mode;
+        if (ret_walker) {
+            ret = get_physical_address(env, &physical, &prot, address,
+                                       access_type, mips_access_type, mmu_idx);
+            if (ret == TLBRET_MATCH) {
+                tlb_set_page(cs, address & TARGET_PAGE_MASK,
+                             physical & TARGET_PAGE_MASK, prot,
+                             mmu_idx, TARGET_PAGE_SIZE);
+                return true;
+            }
+        }
+    }
+#endif
+    if (probe) {
+        return false;
+    }
+#endif
+
+    raise_mmu_exception(env, address, access_type, ret);
+    do_raise_exception_err(env, cs->exception_index, env->error_code, retaddr);
+}
+
+#ifndef CONFIG_USER_ONLY
+hwaddr cpu_mips_translate_address(CPUMIPSState *env, target_ulong address,
+                                  int rw)
+{
+    hwaddr physical;
+    int prot;
+    int access_type;
+    int ret = 0;
+
+    /* data access */
+    access_type = ACCESS_INT;
+    ret = get_physical_address(env, &physical, &prot, address, rw, access_type,
+                               cpu_mmu_index(env, false));
+    if (ret != TLBRET_MATCH) {
+        raise_mmu_exception(env, address, rw, ret);
+        return -1LL;
+    } else {
+        return physical;
+    }
+}
+
+static void set_hflags_for_handler(CPUMIPSState *env)
+{
+    /* Exception handlers are entered in 32-bit mode.  */
+    env->hflags &= ~(MIPS_HFLAG_M16);
+    /* ...except that microMIPS lets you choose.  */
+    if (env->insn_flags & ASE_MICROMIPS) {
+        env->hflags |= (!!(env->CP0_Config3 &
+                           (1 << CP0C3_ISA_ON_EXC))
+                        << MIPS_HFLAG_M16_SHIFT);
+    }
+}
+
+static inline void set_badinstr_registers(CPUMIPSState *env)
+{
+    if (env->insn_flags & ISA_NANOMIPS32) {
+        if (env->CP0_Config3 & (1 << CP0C3_BI)) {
+            uint32_t instr = (cpu_lduw_code(env, env->active_tc.PC)) << 16;
+            if ((instr & 0x10000000) == 0) {
+                instr |= cpu_lduw_code(env, env->active_tc.PC + 2);
+            }
+            env->CP0_BadInstr = instr;
+
+            if ((instr & 0xFC000000) == 0x60000000) {
+                instr = cpu_lduw_code(env, env->active_tc.PC + 4) << 16;
+                env->CP0_BadInstrX = instr;
+            }
+        }
+        return;
+    }
+
+    if (env->hflags & MIPS_HFLAG_M16) {
+        /* TODO: add BadInstr support for microMIPS */
+        return;
+    }
+    if (env->CP0_Config3 & (1 << CP0C3_BI)) {
+        env->CP0_BadInstr = cpu_ldl_code(env, env->active_tc.PC);
+    }
+    if ((env->CP0_Config3 & (1 << CP0C3_BP)) &&
+        (env->hflags & MIPS_HFLAG_BMASK)) {
+        env->CP0_BadInstrP = cpu_ldl_code(env, env->active_tc.PC - 4);
+    }
+}
+
+#endif /* !CONFIG_USER_ONLY */
+
+void mips_cpu_do_interrupt(CPUState *cs)
+{
+#if !defined(CONFIG_USER_ONLY)
+    MIPSCPU *cpu = MIPS_CPU(cs);
+    CPUMIPSState *env = &cpu->env;
+    bool update_badinstr = 0;
+    target_ulong offset;
+    int cause = -1;
+
+    if (qemu_loglevel_mask(CPU_LOG_INT)
+        && cs->exception_index != EXCP_EXT_INTERRUPT) {
+        qemu_log("%s enter: PC " TARGET_FMT_lx " EPC " TARGET_FMT_lx
+                 " %s exception\n",
+                 __func__, env->active_tc.PC, env->CP0_EPC,
+                 mips_exception_name(cs->exception_index));
+    }
+    if (cs->exception_index == EXCP_EXT_INTERRUPT &&
+        (env->hflags & MIPS_HFLAG_DM)) {
+        cs->exception_index = EXCP_DINT;
+    }
+    offset = 0x180;
+    switch (cs->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;
+        /* Setup DExcCode - SDBBP instruction */
+        env->CP0_Debug = (env->CP0_Debug & ~(0x1fULL << CP0DB_DEC)) |
+                         (9 << CP0DB_DEC);
+        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:
+        if (env->insn_flags & ISA_MIPS3) {
+            env->hflags |= MIPS_HFLAG_64;
+            if (!(env->insn_flags & ISA_MIPS_R6) ||
+                env->CP0_Status & (1 << CP0St_KX)) {
+                env->hflags &= ~MIPS_HFLAG_AWRAP;
+            }
+        }
+        env->hflags |= MIPS_HFLAG_DM | 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 &= ~(1U << CP0Ca_BD);
+        }
+        env->active_tc.PC = env->exception_base + 0x480;
+        set_hflags_for_handler(env);
+        break;
+    case EXCP_RESET:
+        cpu_reset(CPU(cpu));
+        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);
+        if (env->insn_flags & ISA_MIPS3) {
+            env->hflags |= MIPS_HFLAG_64;
+            if (!(env->insn_flags & ISA_MIPS_R6) ||
+                env->CP0_Status & (1 << CP0St_KX)) {
+                env->hflags &= ~MIPS_HFLAG_AWRAP;
+            }
+        }
+        env->hflags |= MIPS_HFLAG_CP0;
+        env->hflags &= ~(MIPS_HFLAG_KSU);
+        if (!(env->CP0_Status & (1 << CP0St_EXL))) {
+            env->CP0_Cause &= ~(1U << CP0Ca_BD);
+        }
+        env->active_tc.PC = env->exception_base;
+        set_hflags_for_handler(env);
+        break;
+    case EXCP_EXT_INTERRUPT:
+        cause = 0;
+        if (env->CP0_Cause & (1 << CP0Ca_IV)) {
+            uint32_t spacing = (env->CP0_IntCtl >> CP0IntCtl_VS) & 0x1f;
+
+            if ((env->CP0_Status & (1 << CP0St_BEV)) || spacing == 0) {
+                offset = 0x200;
+            } else {
+                uint32_t vector = 0;
+                uint32_t pending = (env->CP0_Cause & CP0Ca_IP_mask) >> CP0Ca_IP;
+
+                if (env->CP0_Config3 & (1 << CP0C3_VEIC)) {
+                    /*
+                     * For VEIC mode, the external interrupt controller feeds
+                     * the vector through the CP0Cause IP lines.
+                     */
+                    vector = pending;
+                } else {
+                    /*
+                     * Vectored Interrupts
+                     * Mask with Status.IM7-IM0 to get enabled interrupts.
+                     */
+                    pending &= (env->CP0_Status >> CP0St_IM) & 0xff;
+                    /* Find the highest-priority interrupt. */
+                    while (pending >>= 1) {
+                        vector++;
+                    }
+                }
+                offset = 0x200 + (vector * (spacing << 5));
+            }
+        }
+        goto set_EPC;
+    case EXCP_LTLBL:
+        cause = 1;
+        update_badinstr = !(env->error_code & EXCP_INST_NOTAVAIL);
+        goto set_EPC;
+    case EXCP_TLBL:
+        cause = 2;
+        update_badinstr = !(env->error_code & EXCP_INST_NOTAVAIL);
+        if ((env->error_code & EXCP_TLB_NOMATCH) &&
+            !(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 KX = (env->CP0_Status & (1 << CP0St_KX)) != 0;
+
+            if ((R != 0 || UX) && (R != 3 || KX) &&
+                (!(env->insn_flags & (INSN_LOONGSON2E | INSN_LOONGSON2F)))) {
+                offset = 0x080;
+            } else {
+#endif
+                offset = 0x000;
+#if defined(TARGET_MIPS64)
+            }
+#endif
+        }
+        goto set_EPC;
+    case EXCP_TLBS:
+        cause = 3;
+        update_badinstr = 1;
+        if ((env->error_code & EXCP_TLB_NOMATCH) &&
+            !(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 KX = (env->CP0_Status & (1 << CP0St_KX)) != 0;
+
+            if ((R != 0 || UX) && (R != 3 || KX) &&
+                (!(env->insn_flags & (INSN_LOONGSON2E | INSN_LOONGSON2F)))) {
+                offset = 0x080;
+            } else {
+#endif
+                offset = 0x000;
+#if defined(TARGET_MIPS64)
+            }
+#endif
+        }
+        goto set_EPC;
+    case EXCP_AdEL:
+        cause = 4;
+        update_badinstr = !(env->error_code & EXCP_INST_NOTAVAIL);
+        goto set_EPC;
+    case EXCP_AdES:
+        cause = 5;
+        update_badinstr = 1;
+        goto set_EPC;
+    case EXCP_IBE:
+        cause = 6;
+        goto set_EPC;
+    case EXCP_DBE:
+        cause = 7;
+        goto set_EPC;
+    case EXCP_SYSCALL:
+        cause = 8;
+        update_badinstr = 1;
+        goto set_EPC;
+    case EXCP_BREAK:
+        cause = 9;
+        update_badinstr = 1;
+        goto set_EPC;
+    case EXCP_RI:
+        cause = 10;
+        update_badinstr = 1;
+        goto set_EPC;
+    case EXCP_CpU:
+        cause = 11;
+        update_badinstr = 1;
+        env->CP0_Cause = (env->CP0_Cause & ~(0x3 << CP0Ca_CE)) |
+                         (env->error_code << CP0Ca_CE);
+        goto set_EPC;
+    case EXCP_OVERFLOW:
+        cause = 12;
+        update_badinstr = 1;
+        goto set_EPC;
+    case EXCP_TRAP:
+        cause = 13;
+        update_badinstr = 1;
+        goto set_EPC;
+    case EXCP_MSAFPE:
+        cause = 14;
+        update_badinstr = 1;
+        goto set_EPC;
+    case EXCP_FPE:
+        cause = 15;
+        update_badinstr = 1;
+        goto set_EPC;
+    case EXCP_C2E:
+        cause = 18;
+        goto set_EPC;
+    case EXCP_TLBRI:
+        cause = 19;
+        update_badinstr = 1;
+        goto set_EPC;
+    case EXCP_TLBXI:
+        cause = 20;
+        goto set_EPC;
+    case EXCP_MSADIS:
+        cause = 21;
+        update_badinstr = 1;
+        goto set_EPC;
+    case EXCP_MDMX:
+        cause = 22;
+        goto set_EPC;
+    case EXCP_DWATCH:
+        cause = 23;
+        /* XXX: TODO: manage deferred watch exceptions */
+        goto set_EPC;
+    case EXCP_MCHECK:
+        cause = 24;
+        goto set_EPC;
+    case EXCP_THREAD:
+        cause = 25;
+        goto set_EPC;
+    case EXCP_DSPDIS:
+        cause = 26;
+        goto set_EPC;
+    case EXCP_CACHE:
+        cause = 30;
+        offset = 0x100;
+ set_EPC:
+        if (!(env->CP0_Status & (1 << CP0St_EXL))) {
+            env->CP0_EPC = exception_resume_pc(env);
+            if (update_badinstr) {
+                set_badinstr_registers(env);
+            }
+            if (env->hflags & MIPS_HFLAG_BMASK) {
+                env->CP0_Cause |= (1U << CP0Ca_BD);
+            } else {
+                env->CP0_Cause &= ~(1U << CP0Ca_BD);
+            }
+            env->CP0_Status |= (1 << CP0St_EXL);
+            if (env->insn_flags & ISA_MIPS3) {
+                env->hflags |= MIPS_HFLAG_64;
+                if (!(env->insn_flags & ISA_MIPS_R6) ||
+                    env->CP0_Status & (1 << CP0St_KX)) {
+                    env->hflags &= ~MIPS_HFLAG_AWRAP;
+                }
+            }
+            env->hflags |= MIPS_HFLAG_CP0;
+            env->hflags &= ~(MIPS_HFLAG_KSU);
+        }
+        env->hflags &= ~MIPS_HFLAG_BMASK;
+        if (env->CP0_Status & (1 << CP0St_BEV)) {
+            env->active_tc.PC = env->exception_base + 0x200;
+        } else if (cause == 30 && !(env->CP0_Config3 & (1 << CP0C3_SC) &&
+                                    env->CP0_Config5 & (1 << CP0C5_CV))) {
+            /* Force KSeg1 for cache errors */
+            env->active_tc.PC = KSEG1_BASE | (env->CP0_EBase & 0x1FFFF000);
+        } else {
+            env->active_tc.PC = env->CP0_EBase & ~0xfff;
+        }
+
+        env->active_tc.PC += offset;
+        set_hflags_for_handler(env);
+        env->CP0_Cause = (env->CP0_Cause & ~(0x1f << CP0Ca_EC)) |
+                         (cause << CP0Ca_EC);
+        break;
+    default:
+        abort();
+    }
+    if (qemu_loglevel_mask(CPU_LOG_INT)
+        && cs->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
+    cs->exception_index = EXCP_NONE;
+}
+
+#if !defined(CONFIG_USER_ONLY)
+void r4k_invalidate_tlb(CPUMIPSState *env, int idx, int use_extra)
+{
+    CPUState *cs = env_cpu(env);
+    r4k_tlb_t *tlb;
+    target_ulong addr;
+    target_ulong end;
+    uint16_t ASID = env->CP0_EntryHi & env->CP0_EntryHi_ASID_mask;
+    uint32_t MMID = env->CP0_MemoryMapID;
+    bool mi = !!((env->CP0_Config5 >> CP0C5_MI) & 1);
+    uint32_t tlb_mmid;
+    target_ulong mask;
+
+    MMID = mi ? MMID : (uint32_t) ASID;
+
+    tlb = &env->tlb->mmu.r4k.tlb[idx];
+    /*
+     * The qemu TLB is flushed when the ASID/MMID changes, so no need to
+     * flush these entries again.
+     */
+    tlb_mmid = mi ? tlb->MMID : (uint32_t) tlb->ASID;
+    if (tlb->G == 0 && tlb_mmid != MMID) {
+        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(cs, 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(cs, addr);
+            addr += TARGET_PAGE_SIZE;
+        }
+    }
+}
+#endif /* !CONFIG_USER_ONLY */