From 480e79aedd322fcfac17052caff21626ea7c78e2 Mon Sep 17 00:00:00 2001 From: James Hogan Date: Tue, 18 Jul 2017 12:55:57 +0100 Subject: [PATCH] target/mips: Implement segmentation control Implement the optional segmentation control feature in the virtual to physical address translation code. The fixed legacy segment and xkphys handling is replaced with a dynamic layout based on the segmentation control registers (which should be set up even when the feature is not exposed to the guest). Signed-off-by: James Hogan Cc: Yongbok Kim Cc: Aurelien Jarno Reviewed-by: Yongbok Kim [yongbok.kim@imgtec.com: cosmetic changes] Signed-off-by: Yongbok Kim --- target/mips/helper.c | 191 ++++++++++++++++++++++++++++++++++--------- 1 file changed, 152 insertions(+), 39 deletions(-) diff --git a/target/mips/helper.c b/target/mips/helper.c index 7805e5caaf..a2b79e8725 100644 --- a/target/mips/helper.c +++ b/target/mips/helper.c @@ -107,15 +107,107 @@ int r4k_map_address (CPUMIPSState *env, hwaddr *physical, int *prot, return TLBRET_NOMATCH; } +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; + 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; -#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; @@ -148,12 +240,16 @@ static int get_physical_address (CPUMIPSState *env, hwaddr *physical, if (address <= USEG_LIMIT) { /* useg */ - if (env->CP0_Status & (1 << CP0St_ERL)) { - *physical = address & 0xFFFFFFFF; - *prot = PAGE_READ | PAGE_WRITE; + uint16_t segctl; + + if (address >= 0x40000000UL) { + segctl = env->CP0_SegCtl2; } else { - ret = env->tlb->map_address(env, physical, prot, real_address, rw, access_type); + 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 */ @@ -172,10 +268,33 @@ static int get_physical_address (CPUMIPSState *env, hwaddr *physical, } } else if (address < 0xC000000000000000ULL) { /* xkphys */ - if (kernel_mode && KX && - (address & 0x07FFFFFFFFFFFFFFULL) <= env->PAMask) { - *physical = address & env->PAMask; - *prot = PAGE_READ | PAGE_WRITE; + 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; } @@ -190,35 +309,25 @@ static int get_physical_address (CPUMIPSState *env, hwaddr *physical, #endif } else if (address < (int32_t)KSEG1_BASE) { /* kseg0 */ - if (kernel_mode) { - *physical = address - (int32_t)KSEG0_BASE; - *prot = PAGE_READ | PAGE_WRITE; - } else { - ret = TLBRET_BADADDR; - } + ret = get_segctl_physical_address(env, physical, prot, real_address, rw, + access_type, mmu_idx, + env->CP0_SegCtl1 >> 16, 0x1FFFFFFF); } else if (address < (int32_t)KSEG2_BASE) { /* kseg1 */ - if (kernel_mode) { - *physical = address - (int32_t)KSEG1_BASE; - *prot = PAGE_READ | PAGE_WRITE; - } else { - ret = TLBRET_BADADDR; - } + ret = get_segctl_physical_address(env, physical, prot, real_address, rw, + access_type, mmu_idx, + env->CP0_SegCtl1, 0x1FFFFFFF); } else if (address < (int32_t)KSEG3_BASE) { /* sseg (kseg2) */ - if (supervisor_mode || kernel_mode) { - ret = env->tlb->map_address(env, physical, prot, real_address, rw, access_type); - } else { - ret = TLBRET_BADADDR; - } + 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 */ - if (kernel_mode) { - ret = env->tlb->map_address(env, physical, prot, real_address, rw, access_type); - } else { - ret = TLBRET_BADADDR; - } + ret = get_segctl_physical_address(env, physical, prot, real_address, rw, + access_type, mmu_idx, + env->CP0_SegCtl0, 0x1FFFFFFF); } return ret; } @@ -722,15 +831,17 @@ void mips_cpu_do_interrupt(CPUState *cs) #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)) && - (!(env->insn_flags & (INSN_LOONGSON2E | INSN_LOONGSON2F)))) + if ((R != 0 || UX) && (R != 3 || KX) && + (!(env->insn_flags & (INSN_LOONGSON2E | INSN_LOONGSON2F)))) { offset = 0x080; - else + } else { #endif offset = 0x000; +#if defined(TARGET_MIPS64) + } +#endif } goto set_EPC; case EXCP_TLBS: @@ -741,15 +852,17 @@ void mips_cpu_do_interrupt(CPUState *cs) #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)) && - (!(env->insn_flags & (INSN_LOONGSON2E | INSN_LOONGSON2F)))) + if ((R != 0 || UX) && (R != 3 || KX) && + (!(env->insn_flags & (INSN_LOONGSON2E | INSN_LOONGSON2F)))) { offset = 0x080; - else + } else { #endif offset = 0x000; +#if defined(TARGET_MIPS64) + } +#endif } goto set_EPC; case EXCP_AdEL: