Re: [PATCH v2 12/42] esp: remove dma_counter from ESPState

[Laurent Vivier]

Le 09/02/2021 à 20:29, Mark Cave-Ayland a écrit :
> The value of dma_counter is set once at the start of the transfer and remains
> the same until the transfer is complete. This allows the check in 
> esp_transfer_data
> to be simplified since dma_left will always be non-zero until the transfer is
> completed.
> 
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
> ---
>  hw/scsi/esp.c         | 4 +---
>  include/hw/scsi/esp.h | 3 ---
>  2 files changed, 1 insertion(+), 6 deletions(-)
> 
> diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c
> index 02b7876394..6c495b29c0 100644
> --- a/hw/scsi/esp.c
> +++ b/hw/scsi/esp.c
> @@ -229,7 +229,6 @@ static void do_busid_cmd(ESPState *s, uint8_t *buf, 
> uint8_t busid)
>      if (datalen != 0) {
>          s->rregs[ESP_RSTAT] = STAT_TC;
>          s->dma_left = 0;
> -        s->dma_counter = 0;
>          if (datalen > 0) {
>              s->rregs[ESP_RSTAT] |= STAT_DI;
>          } else {
> @@ -543,7 +542,7 @@ void esp_transfer_data(SCSIRequest *req, uint32_t len)
>      s->async_buf = scsi_req_get_buf(req);
>      if (s->dma_left) {
>          esp_do_dma(s);
> -    } else if (s->dma_counter != 0 && s->ti_size <= 0) {
> +    } else if (s->ti_size <= 0) {
>          /*
>           * If this was the last part of a DMA transfer then the
>           * completion interrupt is deferred to here.
> @@ -562,7 +561,6 @@ static void handle_ti(ESPState *s)
>      }
>  
>      dmalen = esp_get_tc(s);
> -    s->dma_counter = dmalen;
>  
>      if (s->do_cmd) {
>          minlen = (dmalen < ESP_CMDBUF_SZ) ? dmalen : ESP_CMDBUF_SZ;
> diff --git a/include/hw/scsi/esp.h b/include/hw/scsi/esp.h
> index 7d92471c5b..b313ef27f2 100644
> --- a/include/hw/scsi/esp.h
> +++ b/include/hw/scsi/esp.h
> @@ -50,9 +50,6 @@ struct ESPState {
>  
>      /* The amount of data left in the current DMA transfer.  */
>      uint32_t dma_left;
> -    /* The size of the current DMA transfer.  Zero if no transfer is in
> -       progress.  */
> -    uint32_t dma_counter;
>      int dma_enabled;
>  
>      uint32_t async_len;
> 

Reviewed-by: Laurent Vivier <laurent@vivier.eu>