Re: [PATCH net-next] net: airoha: Fix typo in REG_CDM2_FWD_CFG configuration

[Simon Horman <horms@kernel.org>]

On Tue, Oct 15, 2024 at 09:58:09AM +0200, Lorenzo Bianconi wrote:
> Fix typo in airoha_fe_init routine configuring CDM2_OAM_QSEL_MASK field
> of REG_CDM2_FWD_CFG register.
> This bug is not introducing any user visible problem since Frame Engine
> CDM2 port is used just by the second QDMA block and we currently enable
> just QDMA1 block connected to the MT7530 dsa switch via CDM1 port.
> 
> Introduced by commit 23020f049327 ("net: airoha: Introduce ethernet
> support for EN7581 SoC")
> 
> Reported-by: ChihWei Cheng <chihwei.cheng@airoha.com>
> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>

Reviewed-by: Simon Horman <horms@kernel.org>

> ---
>  drivers/net/ethernet/mediatek/airoha_eth.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/mediatek/airoha_eth.c b/drivers/net/ethernet/mediatek/airoha_eth.c
> index e037f725f6d3505a8b91815ae26322f5d1b8590c..45665a5b14f5c646d23aaf4830e55a118e9f1a8a 100644
> --- a/drivers/net/ethernet/mediatek/airoha_eth.c
> +++ b/drivers/net/ethernet/mediatek/airoha_eth.c
> @@ -1371,7 +1371,8 @@ static int airoha_fe_init(struct airoha_eth *eth)
>  	airoha_fe_set(eth, REG_GDM_MISC_CFG,
>  		      GDM2_RDM_ACK_WAIT_PREF_MASK |
>  		      GDM2_CHN_VLD_MODE_MASK);
> -	airoha_fe_rmw(eth, REG_CDM2_FWD_CFG, CDM2_OAM_QSEL_MASK, 15);
> +	airoha_fe_rmw(eth, REG_CDM2_FWD_CFG, CDM2_OAM_QSEL_MASK,
> +		      FIELD_PREP(CDM2_OAM_QSEL_MASK, 15));

I agree FIELD_PREP is correct here as it will both mask (not important
in this case) and shift (very important in this case) it's input (15).
This matches how airoha_fe_rmw() will use this argument.

>  
>  	/* init fragment and assemble Force Port */
>  	/* NPU Core-3, NPU Bridge Channel-3 */
> 
> ---
> base-commit: 60b4d49b9621db4b000c9065dd6457c9a0eda80b
> change-id: 20241014-airoha-eth-cdm2-fixes-92d909308204
> 
> Best regards,
> -- 
> Lorenzo Bianconi <lorenzo@kernel.org>
> 
>