Re: [Qemu-devel] [PATCH 07/29] target-sparc: implement UA2005 scratchpad registers

[Richard Henderson]

On 10/01/2016 05:05 AM, Artyom Tarasenko wrote:
> +    case ASI_SCRATCHPAD: /* UA2005 privileged scratchpad */
> +        if (unlikely((addr >= 0x20) && (addr < 0x30))) {
> +            /* Hyperprivileged access only */
> +            cpu_unassigned_access(cs, addr, false, false, 1, size);
> +        }
> +        /* fall through */
> +    case ASI_HYP_SCRATCHPAD: /* UA2005 hyperprivileged scratchpad */
> +        {
> +            unsigned int i = (addr >> 3) & 0x7;
> +            ret = env->scratch[i];
> +            break;
> +        }

It *might* speed things up a teeny bit to implement ASI_HYP_SCRATCHPAD inline. 
E.g.

  case GET_ASI_HYP_SCRATCH:
    {
      TCGv_ptr tmp = tcg_temp_new_ptr();
#if UINTPTR_MAX == UINT32_MAX
      tcg_gen_extrl_i64_i32(tmp, addr);
      tcg_gen_andi_i32(tmp, tmp, 7 << 3);
#else
      tcg_gen_andi_i64(tmp, addr, 7 << 3);
#endif
      tcg_gen_add_ptr(tmp, tmp, cpu_env);
      tcg_gen_ld_i64(dst, tmp, offsetof(CPUSPARCState, scratch));
      tcg_temp_free_ptr(tmp);
    }
    break;

Of course, you can't do that for ASI_SCRATCHPAD because of the dynamic check 
against ADDR.

> @@ -2056,6 +2068,9 @@ void helper_st_asi(CPUSPARCState *env, target_ulong addr, 
> target_ulong val,
>          return;
>      case ASI_INTR_RECEIVE: /* Interrupt data receive */
>          env->ivec_status = val & 0x20;
> +        if (!env->ivec_status) {
> +            cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
> +        }
>          return;

This belongs in some other patch.


r~