Re: [PATCH net-next 08/12] net: airoha: ppe: Configure SRAM PPE entries via the cpu

[Simon Horman <horms@kernel.org>]

On Wed, Oct 15, 2025 at 09:15:08AM +0200, Lorenzo Bianconi wrote:
> Introduce airoha_ppe_foe_commit_sram_entry routine in order to configure
> the SRAM PPE entries directly via the CPU instead of using the NPU APIs.
> This is a preliminary patch to enable netfilter flowtable hw offload for
> AN7583 SoC.
> 
> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
> ---
>  drivers/net/ethernet/airoha/airoha_ppe.c | 30 +++++++++++++++++++++++-------
>  1 file changed, 23 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/net/ethernet/airoha/airoha_ppe.c b/drivers/net/ethernet/airoha/airoha_ppe.c
> index fcfd2d8826a9c2f8f94f1962c2b2a69f67f7f598..0ee2e41489aaa9de9c1e99d242ee0bec11549750 100644
> --- a/drivers/net/ethernet/airoha/airoha_ppe.c
> +++ b/drivers/net/ethernet/airoha/airoha_ppe.c
> @@ -662,6 +662,27 @@ static bool airoha_ppe_foe_compare_entry(struct airoha_flow_table_entry *e,
>  	return !memcmp(&e->data.d, &hwe->d, len - sizeof(hwe->ib1));
>  }
>  
> +static int airoha_ppe_foe_commit_sram_entry(struct airoha_ppe *ppe, u32 hash)
> +{
> +	struct airoha_foe_entry *hwe = ppe->foe + hash * sizeof(*hwe);
> +	bool ppe2 = hash >= PPE_SRAM_NUM_ENTRIES;
> +	u32 *ptr = (u32 *)hwe, val;
> +	int i;
> +
> +	for (i = 0; i < sizeof(*hwe) / 4; i++)
> +		airoha_fe_wr(ppe->eth, REG_PPE_RAM_ENTRY(ppe2, i), ptr[i]);

I realise that a similar pattern it is already used elsewhere,
but '4' seems somewhat magic here.

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