Re: [net PATCH 1/5] octeontx2-af: Adjust Tx credits when MCS external bypass is disabled

[Wojciech Drewek <wojciech.drewek@intel.com>]

On 23.11.2023 06:59, Geetha sowjanya wrote:
> From: Nithin Dabilpuram <ndabilpuram@marvell.com>
> 
> When MCS external bypass is disabled, MCS returns additional
> 2 credits(32B) for every packet Tx'ed on LMAC. To account for
> these extra credits, NIX_AF_TX_LINKX_NORM_CREDIT.CC_MCS_CNT
> needs to be configured as otherwise NIX Tx credits would overflow
> and will never be returned to idle state credit count
> causing issues with credit control and MTU change.
> 
> This patch fixes the same by configuring CC_MCS_CNT at probe
> time for MCS enabled SoC's
> 
> Fixes: bd69476e86fc ("octeontx2-af: cn10k: mcs: Install a default TCAM for normal traffic")
> Signed-off-by: Nithin Dabilpuram <ndabilpuram@marvell.com>
> Signed-off-by: Geetha sowjanya <gakula@marvell.com>
> Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
> ---
>  drivers/net/ethernet/marvell/octeontx2/af/mcs.c     | 12 ++++++++++++
>  drivers/net/ethernet/marvell/octeontx2/af/mcs.h     |  2 ++
>  drivers/net/ethernet/marvell/octeontx2/af/rvu.h     |  1 +
>  drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c |  8 ++++++++
>  4 files changed, 23 insertions(+)
> 
> diff --git a/drivers/net/ethernet/marvell/octeontx2/af/mcs.c b/drivers/net/ethernet/marvell/octeontx2/af/mcs.c
> index c43f19dfbd74..d6effbe46208 100644
> --- a/drivers/net/ethernet/marvell/octeontx2/af/mcs.c
> +++ b/drivers/net/ethernet/marvell/octeontx2/af/mcs.c
> @@ -1219,6 +1219,17 @@ struct mcs *mcs_get_pdata(int mcs_id)
>  	return NULL;
>  }
>  
> +bool is_mcs_bypass(int mcs_id)
> +{
> +	struct mcs *mcs_dev;
> +
> +	list_for_each_entry(mcs_dev, &mcs_list, mcs_list) {
> +		if (mcs_dev->mcs_id == mcs_id)
> +			return mcs_dev->bypass;
> +	}
> +	return true;

If there is no mcs dev with the given id it means it is bypassed?

> +}
> +
>  void mcs_set_port_cfg(struct mcs *mcs, struct mcs_port_cfg_set_req *req)
>  {
>  	u64 val = 0;
> @@ -1447,6 +1458,7 @@ static void mcs_set_external_bypass(struct mcs *mcs, u8 bypass)
>  	else
>  		val &= ~BIT_ULL(6);
>  	mcs_reg_write(mcs, MCSX_MIL_GLOBAL, val);
> +	mcs->bypass = bypass;
>  }
>  
>  static void mcs_global_cfg(struct mcs *mcs)


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