From 6ad4d7eed05a1e23537fc92b50f898f5977f37e6 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 8 Aug 2017 13:42:52 +0100 Subject: [PATCH] target/alpha: Switch to do_transaction_failed() hook Switch the alpha target from the old unassigned_access hook to the new do_transaction_failed hook. This allows us to resolve a ??? in the old hook implementation. The only part of the alpha target that does physical memory accesses is reading the page table -- add a TODO comment there to the effect that we should handle bus faults on page table walks. (Since the palcode doesn't actually do anything useful on a bus fault anyway it's a bit moot for now.) Signed-off-by: Peter Maydell Message-Id: <1502196172-13818-1-git-send-email-peter.maydell@linaro.org> Signed-off-by: Richard Henderson --- target/alpha/cpu.c | 2 +- target/alpha/cpu.h | 8 +++++--- target/alpha/helper.c | 8 ++++++++ target/alpha/mem_helper.c | 19 ++++++++++--------- 4 files changed, 24 insertions(+), 13 deletions(-) diff --git a/target/alpha/cpu.c b/target/alpha/cpu.c index 1ea597b9dd..e6c6aabdf0 100644 --- a/target/alpha/cpu.c +++ b/target/alpha/cpu.c @@ -297,7 +297,7 @@ static void alpha_cpu_class_init(ObjectClass *oc, void *data) #ifdef CONFIG_USER_ONLY cc->handle_mmu_fault = alpha_cpu_handle_mmu_fault; #else - cc->do_unassigned_access = alpha_cpu_unassigned_access; + cc->do_transaction_failed = alpha_cpu_do_transaction_failed; cc->do_unaligned_access = alpha_cpu_do_unaligned_access; cc->get_phys_page_debug = alpha_cpu_get_phys_page_debug; dc->vmsd = &vmstate_alpha_cpu; diff --git a/target/alpha/cpu.h b/target/alpha/cpu.h index 0738e97d6d..6ae240969b 100644 --- a/target/alpha/cpu.h +++ b/target/alpha/cpu.h @@ -486,9 +486,11 @@ void cpu_alpha_store_fpcr (CPUAlphaState *env, uint64_t val); uint64_t cpu_alpha_load_gr(CPUAlphaState *env, unsigned reg); void cpu_alpha_store_gr(CPUAlphaState *env, unsigned reg, uint64_t val); #ifndef CONFIG_USER_ONLY -QEMU_NORETURN void alpha_cpu_unassigned_access(CPUState *cpu, hwaddr addr, - bool is_write, bool is_exec, - int unused, unsigned size); +void alpha_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr, + vaddr addr, unsigned size, + MMUAccessType access_type, + int mmu_idx, MemTxAttrs attrs, + MemTxResult response, uintptr_t retaddr); #endif static inline void cpu_get_tb_cpu_state(CPUAlphaState *env, target_ulong *pc, diff --git a/target/alpha/helper.c b/target/alpha/helper.c index 34121f4cad..36407f77f5 100644 --- a/target/alpha/helper.c +++ b/target/alpha/helper.c @@ -163,6 +163,14 @@ static int get_physical_address(CPUAlphaState *env, target_ulong addr, pt = env->ptbr; + /* TODO: rather than using ldq_phys() to read the page table we should + * use address_space_ldq() so that we can handle the case when + * the page table read gives a bus fault, rather than ignoring it. + * For the existing code the zero data that ldq_phys will return for + * an access to invalid memory will result in our treating the page + * table as invalid, which may even be the right behaviour. + */ + /* L1 page table read. */ index = (addr >> (TARGET_PAGE_BITS + 20)) & 0x3ff; L1pte = ldq_phys(cs->as, pt + index*8); diff --git a/target/alpha/mem_helper.c b/target/alpha/mem_helper.c index 78a7d45590..3c06baa93a 100644 --- a/target/alpha/mem_helper.c +++ b/target/alpha/mem_helper.c @@ -49,22 +49,23 @@ void alpha_cpu_do_unaligned_access(CPUState *cs, vaddr addr, cpu_loop_exit(cs); } -void alpha_cpu_unassigned_access(CPUState *cs, hwaddr addr, - bool is_write, bool is_exec, int unused, - unsigned size) +void alpha_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr, + vaddr addr, unsigned size, + MMUAccessType access_type, + int mmu_idx, MemTxAttrs attrs, + MemTxResult response, uintptr_t retaddr) { AlphaCPU *cpu = ALPHA_CPU(cs); CPUAlphaState *env = &cpu->env; + if (retaddr) { + cpu_restore_state(cs, retaddr); + } + env->trap_arg0 = addr; - env->trap_arg1 = is_write ? 1 : 0; + env->trap_arg1 = access_type == MMU_DATA_STORE ? 1 : 0; cs->exception_index = EXCP_MCHK; env->error_code = 0; - - /* ??? We should cpu_restore_state to the faulting insn, but this hook - does not have access to the retaddr value from the original helper. - It's all moot until the QEMU PALcode grows an MCHK handler. */ - cpu_loop_exit(cs); }