Re: [net PATCH] net: stmmac: replace priv->speed with the portTransmitRate from the tc-cbs parameters

[Wojciech Drewek]

On 07.06.2024 12:33, Xiaolei Wang wrote:
> Since the given offload->sendslope only applies to the
> current link speed, and userspace may reprogram it when
> the link speed changes, don't even bother tracking the
> port's link speed, and deduce the port transmit rate
> from idleslope - sentslope instead.
> 
> Signed-off-by: Xiaolei Wang <xiaolei.wang@xxxxxxxxxxxxx>
> ---

One nit, other than that:
Reviewed-by: Wojciech Drewek <wojciech.drewek@xxxxxxxxx>

>  drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c | 16 ++++++++--------
>  1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
> index 222540b55480..48500864017b 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
> @@ -348,6 +348,7 @@ static int tc_setup_cbs(struct stmmac_priv *priv,
>  	u32 mode_to_use;
>  	u64 value;
>  	int ret;
> +	s64 port_transmit_rate_kbps;

RCT

>  
>  	/* Queue 0 is not AVB capable */
>  	if (queue <= 0 || queue >= tx_queues_count)
> @@ -355,27 +356,24 @@ static int tc_setup_cbs(struct stmmac_priv *priv,
>  	if (!priv->dma_cap.av)
>  		return -EOPNOTSUPP;
>  
> +	port_transmit_rate_kbps = qopt->idleslope - qopt->sendslope;
> +
>  	/* Port Transmit Rate and Speed Divider */
> -	switch (priv->speed) {
> +	switch (div_s64(port_transmit_rate_kbps, 1000)) {
>  	case SPEED_10000:
>  		ptr = 32;
> -		speed_div = 10000000;
>  		break;
>  	case SPEED_5000:
>  		ptr = 32;
> -		speed_div = 5000000;
>  		break;
>  	case SPEED_2500:
>  		ptr = 8;
> -		speed_div = 2500000;
>  		break;
>  	case SPEED_1000:
>  		ptr = 8;
> -		speed_div = 1000000;
>  		break;
>  	case SPEED_100:
>  		ptr = 4;
> -		speed_div = 100000;
>  		break;
>  	default:
>  		return -EOPNOTSUPP;
> @@ -397,11 +395,13 @@ static int tc_setup_cbs(struct stmmac_priv *priv,
>  		priv->plat->tx_queues_cfg[queue].mode_to_use = MTL_QUEUE_DCB;
>  	}
>  
> +	port_transmit_rate_kbps = qopt->idleslope - qopt->sendslope;
> +
>  	/* Final adjustments for HW */
> -	value = div_s64(qopt->idleslope * 1024ll * ptr, speed_div);
> +	value = div_s64(qopt->idleslope * 1024ll * ptr, port_transmit_rate_kbps);
>  	priv->plat->tx_queues_cfg[queue].idle_slope = value & GENMASK(31, 0);
>  
> -	value = div_s64(-qopt->sendslope * 1024ll * ptr, speed_div);
> +	value = div_s64(-qopt->sendslope * 1024ll * ptr, port_transmit_rate_kbps);
>  	priv->plat->tx_queues_cfg[queue].send_slope = value & GENMASK(31, 0);
>  
>  	value = qopt->hicredit * 1024ll * 8;