Hi, Richard.
On 07/23/2021 06:48 AM, Richard Henderson wrote:
> On 7/20/21 11:53 PM, Song Gao wrote:
>> This patch introduces one memory-management-related functions
>> - loongarch_cpu_tlb_fill()
>>
>> Signed-off-by: Song Gao <gaos...@loongson.cn>
>> ---
>> target/loongarch/cpu.c | 1 +
>> target/loongarch/cpu.h | 9 ++++
>> target/loongarch/tlb_helper.c | 103
>> ++++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 113 insertions(+)
>> create mode 100644 target/loongarch/tlb_helper.c
>>
>> diff --git a/target/loongarch/cpu.c b/target/loongarch/cpu.c
>> index 8eaa778..6269dd9 100644
>> --- a/target/loongarch/cpu.c
>> +++ b/target/loongarch/cpu.c
>> @@ -269,6 +269,7 @@ static struct TCGCPUOps loongarch_tcg_ops = {
>> .initialize = loongarch_tcg_init,
>> .synchronize_from_tb = loongarch_cpu_synchronize_from_tb,
>> .cpu_exec_interrupt = loongarch_cpu_exec_interrupt,
>> + .tlb_fill = loongarch_cpu_tlb_fill,
>> };
>> #endif /* CONFIG_TCG */
>> diff --git a/target/loongarch/cpu.h b/target/loongarch/cpu.h
>> index 1db8bb5..5c06122 100644
>> --- a/target/loongarch/cpu.h
>> +++ b/target/loongarch/cpu.h
>> @@ -287,4 +287,13 @@ static inline void compute_hflags(CPULoongArchState
>> *env)
>> const char *loongarch_exception_name(int32_t exception);
>> +/* tlb_helper.c */
>> +bool loongarch_cpu_tlb_fill(CPUState *cs,
>> + vaddr address,
>> + int size,
>> + MMUAccessType access_type,
>> + int mmu_idx,
>> + bool probe,
>> + uintptr_t retaddr);
>> +
>> #endif /* LOONGARCH_CPU_H */
>> diff --git a/target/loongarch/tlb_helper.c b/target/loongarch/tlb_helper.c
>> new file mode 100644
>> index 0000000..b59a995
>> --- /dev/null
>> +++ b/target/loongarch/tlb_helper.c
>> @@ -0,0 +1,103 @@
>> +/*
>> + * LoongArch tlb emulation helpers for qemu.
>> + *
>> + * Copyright (c) 2021 Loongson Technology Corporation Limited
>> + *
>> + * SPDX-License-Identifier: LGPL-2.1+
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +#include "cpu.h"
>> +#include "cpu-csr.h"
>> +#include "exec/helper-proto.h"
>> +#include "exec/exec-all.h"
>> +#include "exec/cpu_ldst.h"
>> +#include "exec/log.h"
>> +
>> +enum {
>> + TLBRET_PE = -7,
>> + TLBRET_XI = -6,
>> + TLBRET_RI = -5,
>> + TLBRET_DIRTY = -4,
>> + TLBRET_INVALID = -3,
>> + TLBRET_NOMATCH = -2,
>> + TLBRET_BADADDR = -1,
>> + TLBRET_MATCH = 0
>> +};
>> +
>> +static void raise_mmu_exception(CPULoongArchState *env, target_ulong
>> address,
>> + MMUAccessType access_type, int tlb_error)
>> +{
>> + CPUState *cs = env_cpu(env);
>> + int exception = 0, error_code = 0;
>> +
>> + if (access_type == MMU_INST_FETCH) {
>> + error_code |= INST_INAVAIL;
>> + }
>> +
>> + switch (tlb_error) {
>> + default:
>> + case TLBRET_BADADDR:
>> + exception = EXCP_ADE;
>> + break;
>> + case TLBRET_NOMATCH:
>> + /* No TLB match for a mapped address */
>> + if (access_type == MMU_DATA_STORE) {
>> + exception = EXCP_TLBS;
>> + } else {
>> + exception = EXCP_TLBL;
>> + }
>> + error_code |= TLB_NOMATCH;
>> + break;
>> + case TLBRET_INVALID:
>> + /* TLB match with no valid bit */
>> + if (access_type == MMU_DATA_STORE) {
>> + exception = EXCP_TLBS;
>> + } else {
>> + exception = EXCP_TLBL;
>> + }
>> + break;
>> + case TLBRET_DIRTY:
>> + exception = EXCP_TLBM;
>> + break;
>> + case TLBRET_XI:
>> + /* Execute-Inhibit Exception */
>> + exception = EXCP_TLBXI;
>> + break;
>> + case TLBRET_RI:
>> + /* Read-Inhibit Exception */
>> + exception = EXCP_TLBRI;
>> + break;
>> + case TLBRET_PE:
>> + /* Privileged Exception */
>> + exception = EXCP_TLBPE;
>> + break;
>> + }
>> +
>> + if (tlb_error == TLBRET_NOMATCH) {
>> + env->CSR_TLBRBADV = address;
>> + env->CSR_TLBREHI = address & (TARGET_PAGE_MASK << 1);
>> + cs->exception_index = exception;
>> + env->error_code = error_code;
>> + return;
>> + }
>> +
>> + /* Raise exception */
>> + env->CSR_BADV = address;
>> + cs->exception_index = exception;
>> + env->error_code = error_code;
>> + env->CSR_TLBEHI = address & (TARGET_PAGE_MASK << 1);
>> +}
>> +
>> +bool loongarch_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
>> + MMUAccessType access_type, int mmu_idx,
>> + bool probe, uintptr_t retaddr)
>> +{
>> + LoongArchCPU *cpu = LOONGARCH_CPU(cs);
>> + CPULoongArchState *env = &cpu->env;
>> + int ret = TLBRET_BADADDR;
>> +
>> + /* data access */
>> + raise_mmu_exception(env, address, access_type, ret);
>> + do_raise_exception_err(env, cs->exception_index, env->error_code,
>> retaddr);
>> +}
>
> Again, almost all of this does not apply for user-only.
>
> r~
>
>>
OK， I‘ll remove it .
Thanks
Song Gao.
