diff options
Diffstat (limited to 'target/riscv/cpu_helper.c')
| -rw-r--r-- | target/riscv/cpu_helper.c | 315 |
1 files changed, 313 insertions, 2 deletions
diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index 8ff6d900f2..3f5fd861a8 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -27,6 +27,7 @@ #include "exec/page-protection.h" #include "instmap.h" #include "tcg/tcg-op.h" +#include "hw/core/tcg-cpu-ops.h" #include "trace.h" #include "semihosting/common-semi.h" #include "system/cpu-timers.h" @@ -874,6 +875,254 @@ void riscv_cpu_set_aia_ireg_rmw_fn(CPURISCVState *env, uint32_t priv, } } +static void riscv_ctr_freeze(CPURISCVState *env, uint64_t freeze_mask, + bool virt) +{ + uint64_t ctl = virt ? env->vsctrctl : env->mctrctl; + + assert((freeze_mask & (~(XCTRCTL_BPFRZ | XCTRCTL_LCOFIFRZ))) == 0); + + if (ctl & freeze_mask) { + env->sctrstatus |= SCTRSTATUS_FROZEN; + } +} + +void riscv_ctr_clear(CPURISCVState *env) +{ + memset(env->ctr_src, 0x0, sizeof(env->ctr_src)); + memset(env->ctr_dst, 0x0, sizeof(env->ctr_dst)); + memset(env->ctr_data, 0x0, sizeof(env->ctr_data)); +} + +static uint64_t riscv_ctr_priv_to_mask(target_ulong priv, bool virt) +{ + switch (priv) { + case PRV_M: + return MCTRCTL_M; + case PRV_S: + if (virt) { + return XCTRCTL_S; + } + return XCTRCTL_S; + case PRV_U: + if (virt) { + return XCTRCTL_U; + } + return XCTRCTL_U; + } + + g_assert_not_reached(); +} + +static uint64_t riscv_ctr_get_control(CPURISCVState *env, target_long priv, + bool virt) +{ + switch (priv) { + case PRV_M: + return env->mctrctl; + case PRV_S: + case PRV_U: + if (virt) { + return env->vsctrctl; + } + return env->mctrctl; + } + + g_assert_not_reached(); +} + +/* + * This function assumes that src privilege and target privilege are not same + * and src privilege is less than target privilege. This includes the virtual + * state as well. + */ +static bool riscv_ctr_check_xte(CPURISCVState *env, target_long src_prv, + bool src_virt) +{ + target_long tgt_prv = env->priv; + bool res = true; + + /* + * VS and U mode are same in terms of xTE bits required to record an + * external trap. See 6.1.2. External Traps, table 8 External Trap Enable + * Requirements. This changes VS to U to simplify the logic a bit. + */ + if (src_virt && src_prv == PRV_S) { + src_prv = PRV_U; + } else if (env->virt_enabled && tgt_prv == PRV_S) { + tgt_prv = PRV_U; + } + + /* VU mode is an outlier here. */ + if (src_virt && src_prv == PRV_U) { + res &= !!(env->vsctrctl & XCTRCTL_STE); + } + + switch (src_prv) { + case PRV_U: + if (tgt_prv == PRV_U) { + break; + } + res &= !!(env->mctrctl & XCTRCTL_STE); + /* fall-through */ + case PRV_S: + if (tgt_prv == PRV_S) { + break; + } + res &= !!(env->mctrctl & MCTRCTL_MTE); + /* fall-through */ + case PRV_M: + break; + } + + return res; +} + +/* + * Special cases for traps and trap returns: + * + * 1- Traps, and trap returns, between enabled modes are recorded as normal. + * 2- Traps from an inhibited mode to an enabled mode, and trap returns from an + * enabled mode back to an inhibited mode, are partially recorded. In such + * cases, the PC from the inhibited mode (source PC for traps, and target PC + * for trap returns) is 0. + * + * 3- Trap returns from an inhibited mode to an enabled mode are not recorded. + * Traps from an enabled mode to an inhibited mode, known as external traps, + * receive special handling. + * By default external traps are not recorded, but a handshake mechanism exists + * to allow partial recording. Software running in the target mode of the trap + * can opt-in to allowing CTR to record traps into that mode even when the mode + * is inhibited. The MTE, STE, and VSTE bits allow M-mode, S-mode, and VS-mode, + * respectively, to opt-in. When an External Trap occurs, and xTE=1, such that + * x is the target privilege mode of the trap, will CTR record the trap. In such + * cases, the target PC is 0. + */ +/* + * CTR arrays are implemented as circular buffers and new entry is stored at + * sctrstatus.WRPTR, but they are presented to software as moving circular + * buffers. Which means, software get's the illusion that whenever a new entry + * is added the whole buffer is moved by one place and the new entry is added at + * the start keeping new entry at idx 0 and older ones follow. + * + * Depth = 16. + * + * buffer [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [A] [B] [C] [D] [E] [F] + * WRPTR W + * entry 7 6 5 4 3 2 1 0 F E D C B A 9 8 + * + * When a new entry is added: + * buffer [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [A] [B] [C] [D] [E] [F] + * WRPTR W + * entry 8 7 6 5 4 3 2 1 0 F E D C B A 9 + * + * entry here denotes the logical entry number that software can access + * using ctrsource, ctrtarget and ctrdata registers. So xiselect 0x200 + * will return entry 0 i-e buffer[8] and 0x201 will return entry 1 i-e + * buffer[7]. Here is how we convert entry to buffer idx. + * + * entry = isel - CTR_ENTRIES_FIRST; + * idx = (sctrstatus.WRPTR - entry - 1) & (depth - 1); + */ +void riscv_ctr_add_entry(CPURISCVState *env, target_long src, target_long dst, + enum CTRType type, target_ulong src_priv, bool src_virt) +{ + bool tgt_virt = env->virt_enabled; + uint64_t src_mask = riscv_ctr_priv_to_mask(src_priv, src_virt); + uint64_t tgt_mask = riscv_ctr_priv_to_mask(env->priv, tgt_virt); + uint64_t src_ctrl = riscv_ctr_get_control(env, src_priv, src_virt); + uint64_t tgt_ctrl = riscv_ctr_get_control(env, env->priv, tgt_virt); + uint64_t depth, head; + bool ext_trap = false; + + /* + * Return immediately if both target and src recording is disabled or if + * CTR is in frozen state. + */ + if ((!(src_ctrl & src_mask) && !(tgt_ctrl & tgt_mask)) || + env->sctrstatus & SCTRSTATUS_FROZEN) { + return; + } + + /* + * With RAS Emul enabled, only allow Indirect, direct calls, Function + * returns and Co-routine swap types. + */ + if (tgt_ctrl & XCTRCTL_RASEMU && + type != CTRDATA_TYPE_INDIRECT_CALL && + type != CTRDATA_TYPE_DIRECT_CALL && + type != CTRDATA_TYPE_RETURN && + type != CTRDATA_TYPE_CO_ROUTINE_SWAP) { + return; + } + + if (type == CTRDATA_TYPE_EXCEPTION || type == CTRDATA_TYPE_INTERRUPT) { + /* Case 2 for traps. */ + if (!(src_ctrl & src_mask)) { + src = 0; + } else if (!(tgt_ctrl & tgt_mask)) { + /* Check if target priv-mode has allowed external trap recording. */ + if (!riscv_ctr_check_xte(env, src_priv, src_virt)) { + return; + } + + ext_trap = true; + dst = 0; + } + } else if (type == CTRDATA_TYPE_EXCEP_INT_RET) { + /* + * Case 3 for trap returns. Trap returns from inhibited mode are not + * recorded. + */ + if (!(src_ctrl & src_mask)) { + return; + } + + /* Case 2 for trap returns. */ + if (!(tgt_ctrl & tgt_mask)) { + dst = 0; + } + } + + /* Ignore filters in case of RASEMU mode or External trap. */ + if (!(tgt_ctrl & XCTRCTL_RASEMU) && !ext_trap) { + /* + * Check if the specific type is inhibited. Not taken branch filter is + * an enable bit and needs to be checked separatly. + */ + bool check = tgt_ctrl & BIT_ULL(type + XCTRCTL_INH_START); + if ((type == CTRDATA_TYPE_NONTAKEN_BRANCH && !check) || + (type != CTRDATA_TYPE_NONTAKEN_BRANCH && check)) { + return; + } + } + + head = get_field(env->sctrstatus, SCTRSTATUS_WRPTR_MASK); + + depth = 16 << get_field(env->sctrdepth, SCTRDEPTH_MASK); + if (tgt_ctrl & XCTRCTL_RASEMU && type == CTRDATA_TYPE_RETURN) { + head = (head - 1) & (depth - 1); + + env->ctr_src[head] &= ~CTRSOURCE_VALID; + env->sctrstatus = + set_field(env->sctrstatus, SCTRSTATUS_WRPTR_MASK, head); + return; + } + + /* In case of Co-routine SWAP we overwrite latest entry. */ + if (tgt_ctrl & XCTRCTL_RASEMU && type == CTRDATA_TYPE_CO_ROUTINE_SWAP) { + head = (head - 1) & (depth - 1); + } + + env->ctr_src[head] = src | CTRSOURCE_VALID; + env->ctr_dst[head] = dst & ~CTRTARGET_MISP; + env->ctr_data[head] = set_field(0, CTRDATA_TYPE_MASK, type); + + head = (head + 1) & (depth - 1); + + env->sctrstatus = set_field(env->sctrstatus, SCTRSTATUS_WRPTR_MASK, head); +} + void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv, bool virt_en) { g_assert(newpriv <= PRV_M && newpriv != PRV_RESERVED); @@ -1223,14 +1472,27 @@ static int get_physical_address(CPURISCVState *env, hwaddr *physical, ppn = pte >> PTE_PPN_SHIFT; } else { if (pte & PTE_RESERVED) { + qemu_log_mask(LOG_GUEST_ERROR, "%s: reserved bits set in PTE: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } if (!pbmte && (pte & PTE_PBMT)) { + /* Reserved without Svpbmt. */ + qemu_log_mask(LOG_GUEST_ERROR, "%s: PBMT bits set in PTE, " + "and Svpbmt extension is disabled: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } if (!riscv_cpu_cfg(env)->ext_svnapot && (pte & PTE_N)) { + /* Reserved without Svnapot extension */ + qemu_log_mask(LOG_GUEST_ERROR, "%s: N bit set in PTE, " + "and Svnapot extension is disabled: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } @@ -1241,14 +1503,19 @@ static int get_physical_address(CPURISCVState *env, hwaddr *physical, /* Invalid PTE */ return TRANSLATE_FAIL; } + if (pte & (PTE_R | PTE_W | PTE_X)) { goto leaf; } - /* Inner PTE, continue walking */ if (pte & (PTE_D | PTE_A | PTE_U | PTE_ATTR)) { + /* D, A, and U bits are reserved in non-leaf/inner PTEs */ + qemu_log_mask(LOG_GUEST_ERROR, "%s: D, A, or U bits set in non-leaf PTE: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } + /* Inner PTE, continue walking */ base = ppn << PGSHIFT; } @@ -1258,10 +1525,17 @@ static int get_physical_address(CPURISCVState *env, hwaddr *physical, leaf: if (ppn & ((1ULL << ptshift) - 1)) { /* Misaligned PPN */ + qemu_log_mask(LOG_GUEST_ERROR, "%s: PPN bits in PTE is misaligned: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } if (!pbmte && (pte & PTE_PBMT)) { /* Reserved without Svpbmt. */ + qemu_log_mask(LOG_GUEST_ERROR, "%s: PBMT bits set in PTE, " + "and Svpbmt extension is disabled: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } @@ -1697,6 +1971,23 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, } else if (probe) { return false; } else { + int wp_access = 0; + + if (access_type == MMU_DATA_LOAD) { + wp_access |= BP_MEM_READ; + } else if (access_type == MMU_DATA_STORE) { + wp_access |= BP_MEM_WRITE; + } + + /* + * If a watchpoint isn't found for 'addr' this will + * be a no-op and we'll resume the mmu_exception path. + * Otherwise we'll throw a debug exception and execution + * will continue elsewhere. + */ + cpu_check_watchpoint(cs, address, size, MEMTXATTRS_UNSPECIFIED, + wp_access, retaddr); + raise_mmu_exception(env, address, access_type, pmp_violation, first_stage_error, two_stage_lookup, two_stage_indirect_error); @@ -1975,10 +2266,13 @@ void riscv_cpu_do_interrupt(CPUState *cs) !(env->mip & (1ULL << cause)); bool smode_double_trap = false; uint64_t hdeleg = async ? env->hideleg : env->hedeleg; + const bool prev_virt = env->virt_enabled; + const target_ulong prev_priv = env->priv; target_ulong tval = 0; target_ulong tinst = 0; target_ulong htval = 0; target_ulong mtval2 = 0; + target_ulong src; int sxlen = 0; int mxlen = 16 << riscv_cpu_mxl(env); bool nnmi_excep = false; @@ -2084,7 +2378,9 @@ void riscv_cpu_do_interrupt(CPUState *cs) mode = env->priv <= PRV_S && cause < 64 && (((deleg >> cause) & 1) || s_injected || vs_injected) ? PRV_S : PRV_M; - vsmode_exc = env->virt_enabled && (((hdeleg >> cause) & 1) || vs_injected); + vsmode_exc = env->virt_enabled && cause < 64 && + (((hdeleg >> cause) & 1) || vs_injected); + /* * Check double trap condition only if already in S-mode and targeting * S-mode @@ -2162,6 +2458,8 @@ void riscv_cpu_do_interrupt(CPUState *cs) env->pc = (env->stvec >> 2 << 2) + ((async && (env->stvec & 3) == 1) ? cause * 4 : 0); riscv_cpu_set_mode(env, PRV_S, virt); + + src = env->sepc; } else { /* * If the hart encounters an exception while executing in M-mode @@ -2246,6 +2544,19 @@ void riscv_cpu_do_interrupt(CPUState *cs) ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0); } riscv_cpu_set_mode(env, PRV_M, virt); + src = env->mepc; + } + + if (riscv_cpu_cfg(env)->ext_smctr || riscv_cpu_cfg(env)->ext_ssctr) { + if (async && cause == IRQ_PMU_OVF) { + riscv_ctr_freeze(env, XCTRCTL_LCOFIFRZ, virt); + } else if (!async && cause == RISCV_EXCP_BREAKPOINT) { + riscv_ctr_freeze(env, XCTRCTL_BPFRZ, virt); + } + + riscv_ctr_add_entry(env, src, env->pc, + async ? CTRDATA_TYPE_INTERRUPT : CTRDATA_TYPE_EXCEPTION, + prev_priv, prev_virt); } /* |