ISA v3.1 introduced prefix instructions. Among the changes, various synchronous interrupts report whether they were caused by a prefix instruction in (H)SRR1.
The case of instruction fetch that causes an HDSI due to access of a process-scoped table faulting on the partition scoped translation is the tricky one. As with ISIs and HISIs, this does not try to set the prefix bit because there is no instruction image to be loaded. The HDSI needs the originating access type to be passed through to the handler to distinguish this from HDSIs that fault translating process scoped tables originating from a load or store instruction (in that case the prefix bit should be provided). Reviewed-by: Fabiano Rosas <[email protected]> Signed-off-by: Nicholas Piggin <[email protected]> --- Since v2: - Fix a bug where ifetch access causing HDSI due to process scoped table access failing on partition scope translation would go into infinite recursive fault attempting to load the instruction image. This requires more data from the page fault to distinguish this from the same case but initiated by a load or store (in which case we can load the instruction image). target/ppc/excp_helper.c | 44 ++++++++++++++++++++++++++++++++++++++++ target/ppc/mmu-radix64.c | 14 ++++++++++--- 2 files changed, 55 insertions(+), 3 deletions(-) diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c index 453750a9d6..27d321c15f 100644 --- a/target/ppc/excp_helper.c +++ b/target/ppc/excp_helper.c @@ -1346,12 +1346,21 @@ static bool books_vhyp_handles_hv_excp(PowerPCCPU *cpu) return false; } +static bool is_prefix_excp(CPUPPCState *env, uint32_t insn) +{ + if (!(env->insns_flags2 & PPC2_ISA310)) { + return false; + } + return ((insn & 0xfc000000) == 0x04000000); +} + static void powerpc_excp_books(PowerPCCPU *cpu, int excp) { CPUState *cs = CPU(cpu); CPUPPCState *env = &cpu->env; target_ulong msr, new_msr, vector; int srr0, srr1, lev = -1; + uint32_t insn = 0; /* new srr1 value excluding must-be-zero bits */ msr = env->msr & ~0x783f0000ULL; @@ -1390,6 +1399,41 @@ static void powerpc_excp_books(PowerPCCPU *cpu, int excp) vector |= env->excp_prefix; + switch (excp) { + case POWERPC_EXCP_HDSI: + /* HDSI PRTABLE_FAULT has the originating access type in error_code */ + if ((env->spr[SPR_HDSISR] & DSISR_PRTABLE_FAULT) && + (env->error_code == MMU_INST_FETCH)) { + /* + * Fetch failed due to partition scope translation, so prefix + * indication is not relevant (and attempting to load the + * instruction at NIP would cause recursive faults with the same + * translation). + */ + break; + } + /* fall through */ + case POWERPC_EXCP_MCHECK: + case POWERPC_EXCP_DSI: + case POWERPC_EXCP_DSEG: + case POWERPC_EXCP_ALIGN: + case POWERPC_EXCP_PROGRAM: + case POWERPC_EXCP_FPU: + case POWERPC_EXCP_TRACE: + case POWERPC_EXCP_HV_EMU: + case POWERPC_EXCP_VPU: + case POWERPC_EXCP_VSXU: + case POWERPC_EXCP_FU: + case POWERPC_EXCP_HV_FU: + insn = ppc_ldl_code(env, env->nip); + if (is_prefix_excp(env, insn)) { + msr |= PPC_BIT(34); + } + break; + default: + break; + } + switch (excp) { case POWERPC_EXCP_MCHECK: /* Machine check exception */ if (!FIELD_EX64(env->msr, MSR, ME)) { diff --git a/target/ppc/mmu-radix64.c b/target/ppc/mmu-radix64.c index 1fc1ba3ecf..920084bd8f 100644 --- a/target/ppc/mmu-radix64.c +++ b/target/ppc/mmu-radix64.c @@ -145,6 +145,13 @@ static void ppc_radix64_raise_hsi(PowerPCCPU *cpu, MMUAccessType access_type, CPUState *cs = CPU(cpu); CPUPPCState *env = &cpu->env; + env->error_code = 0; + if (cause & DSISR_PRTABLE_FAULT) { + /* HDSI PRTABLE_FAULT gets the originating access type in error_code */ + env->error_code = access_type; + access_type = MMU_DATA_LOAD; + } + qemu_log_mask(CPU_LOG_MMU, "%s for %s @0x%"VADDR_PRIx" 0x%" HWADDR_PRIx" cause %08x\n", __func__, access_str(access_type), @@ -166,7 +173,6 @@ static void ppc_radix64_raise_hsi(PowerPCCPU *cpu, MMUAccessType access_type, env->spr[SPR_HDSISR] = cause; env->spr[SPR_HDAR] = eaddr; env->spr[SPR_ASDR] = g_raddr; - env->error_code = 0; break; default: g_assert_not_reached(); @@ -369,13 +375,14 @@ static bool validate_pate(PowerPCCPU *cpu, uint64_t lpid, ppc_v3_pate_t *pate) } static int ppc_radix64_partition_scoped_xlate(PowerPCCPU *cpu, - MMUAccessType access_type, + MMUAccessType orig_access_type, vaddr eaddr, hwaddr g_raddr, ppc_v3_pate_t pate, hwaddr *h_raddr, int *h_prot, int *h_page_size, bool pde_addr, int mmu_idx, bool guest_visible) { + MMUAccessType access_type = orig_access_type; int fault_cause = 0; hwaddr pte_addr; uint64_t pte; @@ -404,7 +411,8 @@ static int ppc_radix64_partition_scoped_xlate(PowerPCCPU *cpu, fault_cause |= DSISR_PRTABLE_FAULT; } if (guest_visible) { - ppc_radix64_raise_hsi(cpu, access_type, eaddr, g_raddr, fault_cause); + ppc_radix64_raise_hsi(cpu, orig_access_type, + eaddr, g_raddr, fault_cause); } return 1; } -- 2.40.1
