Re: [PATCH net-next v2 09/21] net: ravb: Split GTI computation and set operations

From: Sergey Shtylyov
Date: Sat Dec 16 2023 - 11:38:34 EST


On 12/14/23 2:45 PM, Claudiu wrote:

> From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
>
> ravb_set_gti() was computing the value of GTI based on the reference clock
> rate and then applied it to register. This was done on the driver's probe
> function. In order to implement runtime PM for all IP variants (as some IP
> variants switches to reset operation mode (and thus the register's content

Again, operating mode...

> is lost) when module standby is configured through clock APIs) the GTI was

The GTI what? Setup?

> split in 2 parts: one computing the value of the GTI register (done in the
> driver's probe function) and one applying the computed value to register
> (done in the driver's ndo_open API).
>
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
[...]

> diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
> index e0f8276cffed..76202395b68d 100644
> --- a/drivers/net/ethernet/renesas/ravb.h
> +++ b/drivers/net/ethernet/renesas/ravb.h
> @@ -1106,6 +1106,8 @@ struct ravb_private {
>
> const struct ravb_hw_info *info;
> struct reset_control *rstc;
> +
> + uint64_t gti_tiv;

Please use the kernel type, u64; uint64_t is for userland, IIRC.

[...]
> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
> index d7f6e8ea8e79..5e01e03e1b43 100644
> --- a/drivers/net/ethernet/renesas/ravb_main.c
> +++ b/drivers/net/ethernet/renesas/ravb_main.c
> @@ -1750,6 +1750,51 @@ static int ravb_set_reset_mode(struct net_device *ndev)
> return error;
> }
>
> +static int ravb_set_gti(struct net_device *ndev)
> +{
[...]
> + /* Request GTI loading */
> + ravb_modify(ndev, GCCR, GCCR_LTI, GCCR_LTI);
> +
> + /* Check completion status. */
> + return ravb_wait(ndev, GCCR, GCCR_LTI, 0);

Is this really necessary?

[...]
> @@ -1767,6 +1812,10 @@ static int ravb_open(struct net_device *ndev)
> goto out_napi_off;
> ravb_emac_init(ndev);
>
> + error = ravb_set_gti(ndev);
> + if (error)
> + goto out_dma_stop;
> +

Hm... belongs in ravb_dmac_init() now, as it seems...

[...]

MBR, Sergey