Re: [PATCH] hw:w25p80: Add STATE_STANDBY to handle incorrect command

[Dan Zhang]

Hi Cedric,

I am sorry that accidently submit a pre-view code change as a patch using the
git-sendmail. 
I originally mean to copy the following code in email reply and let
commnity get better understand my proposal.

Let me submit a formal patch in seperate thread. And will remove the
code using this STATE_STANDBY state, as those code shall be in @iris WP#
patch.

BRs
Dan

On Tue, Jun 14, 2022 at 09:02:46AM -0700, Dan Zhang wrote:
> ---
>  hw/block/m25p80.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/hw/block/m25p80.c b/hw/block/m25p80.c
> index b6bd430a99..3bb0466dca 100644
> --- a/hw/block/m25p80.c
> +++ b/hw/block/m25p80.c
> @@ -423,6 +423,7 @@ typedef enum {
>      STATE_COLLECTING_DATA,
>      STATE_COLLECTING_VAR_LEN_DATA,
>      STATE_READING_DATA,
> +    STATE_STANDBY,
>  } CMDState;
>  
>  typedef enum {
> @@ -1218,6 +1219,9 @@ static void decode_new_cmd(Flash *s, uint32_t value)
>              || !s->write_enable) {
>              qemu_log_mask(LOG_GUEST_ERROR,
>                            "M25P80: Status register write is disabled!\n");
> +         qemu_log_mask(LOG_GUEST_ERROR,
> +                          "M25P80: switch to standby, re-aseert CS to 
> reactivate \n");
> +         s->state = STATE_STANDBY;
>              break;
>          }
>  
> @@ -1472,6 +1476,9 @@ static uint32_t m25p80_transfer8(SSIPeripheral *ss, 
> uint32_t tx)
>                            s->cur_addr, (uint8_t)tx);
>  
>      switch (s->state) {
> +    case STATE_STANDBY:
> +     r = 0xFFFFFFFF; /* StandBy state SO shall be HiZ */
> +     break;
>  
>      case STATE_PAGE_PROGRAM:
>          trace_m25p80_page_program(s, s->cur_addr, (uint8_t)tx);
> -- 
> 2.34.3
>