Re: [PATCH net] net: ethernet: mtk_eth_soc: add reset bits for MT7988

[Simon Horman]

On Fri, Aug 18, 2023 at 07:15:24PM +0100, Daniel Golle wrote:
> Add bits needed to reset the frame engine on MT7988.
> 
> Fixes: 445eb6448ed3 ("net: ethernet: mtk_eth_soc: add basic support for MT7988 SoC")
> Signed-off-by: Daniel Golle <daniel@xxxxxxxxxxxxxx>
> ---
>  drivers/net/ethernet/mediatek/mtk_eth_soc.c | 76 +++++++++++++++------
>  drivers/net/ethernet/mediatek/mtk_eth_soc.h | 11 ++-
>  2 files changed, 64 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> index fe05c90202699..2482f47313085 100644
> --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> @@ -3613,19 +3613,34 @@ static void mtk_hw_reset(struct mtk_eth *eth)
>  {
>  	u32 val;
>  
> -	if (mtk_is_netsys_v2_or_greater(eth)) {
> +	if (mtk_is_netsys_v2_or_greater(eth))
>  		regmap_write(eth->ethsys, ETHSYS_FE_RST_CHK_IDLE_EN, 0);
> +
> +	if (mtk_is_netsys_v3_or_greater(eth)) {
> +		val = RSTCTRL_PPE0_V3;
> +
> +		if (MTK_HAS_CAPS(eth->soc->caps, MTK_RSTCTRL_PPE1))
> +			val |= RSTCTRL_PPE1_V3;
> +
> +		if (MTK_HAS_CAPS(eth->soc->caps, MTK_RSTCTRL_PPE2))
> +			val |= RSTCTRL_PPE2;
> +
> +		val |= RSTCTRL_WDMA0 | RSTCTRL_WDMA1 | RSTCTRL_WDMA2;
> +	} else if (mtk_is_netsys_v2_or_greater(eth)) {
>  		val = RSTCTRL_PPE0_V2;
> +
> +		if (MTK_HAS_CAPS(eth->soc->caps, MTK_RSTCTRL_PPE1))
> +			val |= RSTCTRL_PPE1;
>  	} else {
>  		val = RSTCTRL_PPE0;
>  	}
>  
> -	if (MTK_HAS_CAPS(eth->soc->caps, MTK_RSTCTRL_PPE1))
> -		val |= RSTCTRL_PPE1;
> -
>  	ethsys_reset(eth, RSTCTRL_ETH | RSTCTRL_FE | val);
>  
> -	if (mtk_is_netsys_v2_or_greater(eth))
> +	if (mtk_is_netsys_v3_or_greater(eth))
> +		regmap_write(eth->ethsys, ETHSYS_FE_RST_CHK_IDLE_EN,
> +			     0x6f8ff);
> +	else if (mtk_is_netsys_v2_or_greater(eth))
>  		regmap_write(eth->ethsys, ETHSYS_FE_RST_CHK_IDLE_EN,
>  			     0x3ffffff);
>  }
> @@ -3651,13 +3666,21 @@ static void mtk_hw_warm_reset(struct mtk_eth *eth)
>  		return;
>  	}
>  
> -	if (mtk_is_netsys_v2_or_greater(eth))
> +	if (mtk_is_netsys_v3_or_greater(eth)) {
> +		rst_mask = RSTCTRL_ETH | RSTCTRL_PPE0_V3;
> +		if (MTK_HAS_CAPS(eth->soc->caps, MTK_RSTCTRL_PPE1))
> +			rst_mask |= RSTCTRL_PPE1_V3;
> +		if (MTK_HAS_CAPS(eth->soc->caps, MTK_RSTCTRL_PPE2))
> +			rst_mask |= RSTCTRL_PPE2;
> +
> +		rst_mask |= RSTCTRL_WDMA0 | RSTCTRL_WDMA1 | RSTCTRL_WDMA2;
> +	} else if (mtk_is_netsys_v2_or_greater(eth)) {
>  		rst_mask = RSTCTRL_ETH | RSTCTRL_PPE0_V2;
> -	else
> +		if (MTK_HAS_CAPS(eth->soc->caps, MTK_RSTCTRL_PPE1))
> +			rst_mask |= RSTCTRL_PPE1;
> +	} else {
>  		rst_mask = RSTCTRL_ETH | RSTCTRL_PPE0;
> -
> -	if (MTK_HAS_CAPS(eth->soc->caps, MTK_RSTCTRL_PPE1))
> -		rst_mask |= RSTCTRL_PPE1;
> +	}
>  
>  	regmap_update_bits(eth->ethsys, ETHSYS_RSTCTRL, rst_mask, rst_mask);
>  

Hi Daniel,

The bits set by the code in the above two hunks seem both complex
and similar. At the risk of suggesting excessive complexity,
I do wonder if they can be consolidated somehow.

Maybe the approach you have taken is best as a fix for net.
But a follow-up could be considered for net-next.
Just an idea.

...