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

[Mark Cave-Ayland]

On 01/03/2021 21:24, Laurent Vivier wrote:

> 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.

That's true - I think it's just done that way since that was how it was originally 
written in the section below where I copied it from. I'll remove it in the next version.

> > +    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>


ATB,

Mark.