Re: [PATCH] target/rx/cpu: Use address_space_ldl() to read reset vector address

[Philippe Mathieu-Daudé]

On 3/15/20 2:48 PM, Philippe Mathieu-Daudé wrote:
> From: Philippe Mathieu-Daudé <address@hidden>

Hmm author email should be <address@hidden>...

> The RX code flash is not a Masked ROM but a EEPROM (electrically
> erasable programmable flash memory).
> When implementing the flash hardware, the rom_ptr() returns NULL
> and the reset vector is not set.
> Instead, use the address_space ld/st API to fetch the reset vector
> address from the code flash.
>
> Signed-off-by: Philippe Mathieu-Daudé <address@hidden>
> ---
> Based-on: <address@hidden>
>
> Same issue might occurs in Cortex-M arm_cpu_reset()
> ---
>   target/rx/cpu.c | 10 ++++------
>   1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/target/rx/cpu.c b/target/rx/cpu.c
> index 9c224a273c..d3bd09e753 100644
> --- a/target/rx/cpu.c
> +++ b/target/rx/cpu.c
> @@ -26,6 +26,8 @@
>   #include "hw/loader.h"
>   #include "fpu/softfloat.h"
>   
> +#define CPU_RESET_VECTOR 0xfffffffc
> +
>   static void rx_cpu_set_pc(CPUState *cs, vaddr value)
>   {
>       RXCPU *cpu = RXCPU(cs);
> @@ -51,17 +53,13 @@ static void rx_cpu_reset(CPUState *s)
>       RXCPU *cpu = RXCPU(s);
>       RXCPUClass *rcc = RXCPU_GET_CLASS(cpu);
>       CPURXState *env = &cpu->env;
> -    uint32_t *resetvec;
>   
>       rcc->parent_reset(s);
>   
>       memset(env, 0, offsetof(CPURXState, end_reset_fields));
>   
> -    resetvec = rom_ptr(0xfffffffc, 4);
> -    if (resetvec) {
> -        /* In the case of kernel, it is ignored because it is not set. */
> -        env->pc = ldl_p(resetvec);
> -    }
> +    env->pc = address_space_ldl(cpu_get_address_space(s, 0),
> +                                CPU_RESET_VECTOR, MEMTXATTRS_UNSPECIFIED, 
> NULL);
>       rx_cpu_unpack_psw(env, 0, 1);
>       env->regs[0] = env->isp = env->usp = 0;
>       env->fpsw = 0;