Re: [PATCH v2 09/42] esp: introduce esp_get_tc() and esp_set_tc()

[Laurent Vivier]

Le 09/02/2021 à 20:29, Mark Cave-Ayland a écrit :
> This simplifies reading and writing the TC register value without having to
> manually shift each individual 8-bit value.
> 
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  hw/scsi/esp.c | 38 +++++++++++++++++++++++---------------
>  1 file changed, 23 insertions(+), 15 deletions(-)
> 
> diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c
> index e82e75d490..3a39450930 100644
> --- a/hw/scsi/esp.c
> +++ b/hw/scsi/esp.c
> @@ -98,6 +98,24 @@ void esp_request_cancelled(SCSIRequest *req)
>      }
>  }
>  
> +static uint32_t esp_get_tc(ESPState *s)
> +{
> +    uint32_t dmalen;
> +
> +    dmalen = s->rregs[ESP_TCLO];
> +    dmalen |= s->rregs[ESP_TCMID] << 8;
> +    dmalen |= s->rregs[ESP_TCHI] << 16;
> +
> +    return dmalen;
> +}
> +
> +static void esp_set_tc(ESPState *s, uint32_t dmalen)
> +{
> +    s->rregs[ESP_TCLO] = dmalen & 0xff;

The "& 0xff" is not needed as rregs is uint8_t.

> +    s->rregs[ESP_TCMID] = dmalen >> 8;
> +    s->rregs[ESP_TCHI] = dmalen >> 16;
> +}
> +
>  static void set_pdma(ESPState *s, enum pdma_origin_id origin,
>                       uint32_t index, uint32_t len)
>  {
> @@ -157,9 +175,7 @@ static uint32_t get_cmd(ESPState *s, uint8_t *buf, 
> uint8_t buflen)
>  
>      target = s->wregs[ESP_WBUSID] & BUSID_DID;
>      if (s->dma) {
> -        dmalen = s->rregs[ESP_TCLO];
> -        dmalen |= s->rregs[ESP_TCMID] << 8;
> -        dmalen |= s->rregs[ESP_TCHI] << 16;
> +        dmalen = esp_get_tc(s);
>          if (dmalen > buflen) {
>              return 0;
>          }
> @@ -348,9 +364,7 @@ static void esp_dma_done(ESPState *s)
>      s->rregs[ESP_RINTR] = INTR_BS;
>      s->rregs[ESP_RSEQ] = 0;
>      s->rregs[ESP_RFLAGS] = 0;
> -    s->rregs[ESP_TCLO] = 0;
> -    s->rregs[ESP_TCMID] = 0;
> -    s->rregs[ESP_TCHI] = 0;
> +    esp_set_tc(s, 0);
>      esp_raise_irq(s);
>  }
>  
> @@ -536,9 +550,7 @@ static void handle_ti(ESPState *s)
>          return;
>      }
>  
> -    dmalen = s->rregs[ESP_TCLO];
> -    dmalen |= s->rregs[ESP_TCMID] << 8;
> -    dmalen |= s->rregs[ESP_TCHI] << 16;
> +    dmalen = esp_get_tc(s);
>      if (dmalen == 0) {
>          dmalen = 0x10000;
>      }
> @@ -889,9 +901,7 @@ static void sysbus_esp_pdma_write(void *opaque, hwaddr 
> addr,
>  
>      trace_esp_pdma_write(size);
>  
> -    dmalen = s->rregs[ESP_TCLO];
> -    dmalen |= s->rregs[ESP_TCMID] << 8;
> -    dmalen |= s->rregs[ESP_TCHI] << 16;
> +    dmalen = esp_get_tc(s);
>      if (dmalen == 0 || s->pdma_len == 0) {
>          return;
>      }
> @@ -908,9 +918,7 @@ static void sysbus_esp_pdma_write(void *opaque, hwaddr 
> addr,
>          dmalen -= 2;
>          break;
>      }
> -    s->rregs[ESP_TCLO] = dmalen & 0xff;
> -    s->rregs[ESP_TCMID] = dmalen >> 8;
> -    s->rregs[ESP_TCHI] = dmalen >> 16;
> +    esp_set_tc(s, dmalen);
>      if (s->pdma_len == 0 && s->pdma_cb) {
>          esp_lower_drq(s);
>          s->pdma_cb(s);
> 

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