[PATCH] net: ethernet: mediatek: ppe: add support for flow accounting

[Felix Fietkau]

On 01.11.22 20:12, Daniel Golle wrote:
> The PPE units found in MT7622 and newer support packet and byte
> accounting of hw-offloaded flows. Add support for reading those
> counters as found in MediaTek's SDK[1].
> 
> [1]: https://git01.mediatek.com/plugins/gitiles/openwrt/feeds/mtk-openwrt-feeds/+/bc6a6a375c800dc2b80e1a325a2c732d1737df92
> Signed-off-by: Daniel Golle <daniel at makrotopia.org>
> ---
>   drivers/net/ethernet/mediatek/mtk_eth_soc.c   |  11 +-
>   drivers/net/ethernet/mediatek/mtk_eth_soc.h   |   1 +
>   drivers/net/ethernet/mediatek/mtk_ppe.c       | 122 +++++++++++++++++-
>   drivers/net/ethernet/mediatek/mtk_ppe.h       |  23 +++-
>   .../net/ethernet/mediatek/mtk_ppe_debugfs.c   |   9 +-
>   .../net/ethernet/mediatek/mtk_ppe_offload.c   |   7 +
>   drivers/net/ethernet/mediatek/mtk_ppe_regs.h  |  14 ++
>   7 files changed, 178 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> index 789268b15106ec..5fcd66fca7a089 100644
> --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> @@ -4221,6 +4223,7 @@ static const struct mtk_soc_data mt2701_data = {
>   	.hw_features = MTK_HW_FEATURES,
>   	.required_clks = MT7623_CLKS_BITMAP,
>   	.required_pctl = true,
> +	.has_accounting = false,
>   	.txrx = {
>   		.txd_size = sizeof(struct mtk_tx_dma),
>   		.rxd_size = sizeof(struct mtk_rx_dma),
> @@ -4239,6 +4242,7 @@ static const struct mtk_soc_data mt7621_data = {
>   	.required_pctl = false,
>   	.offload_version = 2,
>   	.hash_offset = 2,
> +	.has_accounting = false,
>   	.foe_entry_size = sizeof(struct mtk_foe_entry) - 16,
>   	.txrx = {
>   		.txd_size = sizeof(struct mtk_tx_dma),
> @@ -4259,6 +4263,7 @@ static const struct mtk_soc_data mt7622_data = {
>   	.required_pctl = false,
>   	.offload_version = 2,
>   	.hash_offset = 2,
> +	.has_accounting = true,
>   	.foe_entry_size = sizeof(struct mtk_foe_entry) - 16,
>   	.txrx = {
>   		.txd_size = sizeof(struct mtk_tx_dma),
> @@ -4278,6 +4283,7 @@ static const struct mtk_soc_data mt7623_data = {
>   	.required_pctl = true,
>   	.offload_version = 2,
>   	.hash_offset = 2,
> +	.has_accounting = false,
>   	.foe_entry_size = sizeof(struct mtk_foe_entry) - 16,
>   	.txrx = {
>   		.txd_size = sizeof(struct mtk_tx_dma),
> @@ -4296,6 +4302,7 @@ static const struct mtk_soc_data mt7629_data = {
>   	.hw_features = MTK_HW_FEATURES,
>   	.required_clks = MT7629_CLKS_BITMAP,
>   	.required_pctl = false,
> +	.has_accounting = true,
>   	.txrx = {
>   		.txd_size = sizeof(struct mtk_tx_dma),
>   		.rxd_size = sizeof(struct mtk_rx_dma),
> @@ -4315,6 +4322,7 @@ static const struct mtk_soc_data mt7986_data = {
>   	.required_pctl = false,
>   	.hash_offset = 4,
>   	.foe_entry_size = sizeof(struct mtk_foe_entry),
> +	.has_accounting = true,
>   	.txrx = {
>   		.txd_size = sizeof(struct mtk_tx_dma_v2),
>   		.rxd_size = sizeof(struct mtk_rx_dma_v2),
> @@ -4331,6 +4339,7 @@ static const struct mtk_soc_data rt5350_data = {
>   	.hw_features = MTK_HW_FEATURES_MT7628,
>   	.required_clks = MT7628_CLKS_BITMAP,
>   	.required_pctl = false,
> +	.has_accounting = false,
>   	.txrx = {
>   		.txd_size = sizeof(struct mtk_tx_dma),
>   		.rxd_size = sizeof(struct mtk_rx_dma),
You can leave out the .has_accounting = false assignments.

> diff --git a/drivers/net/ethernet/mediatek/mtk_ppe.c b/drivers/net/ethernet/mediatek/mtk_ppe.c
> index 2d8ca99f2467ff..bc4660da28451b 100644
> --- a/drivers/net/ethernet/mediatek/mtk_ppe.c
> +++ b/drivers/net/ethernet/mediatek/mtk_ppe.c
> @@ -545,6 +592,16 @@ __mtk_foe_entry_commit(struct mtk_ppe *ppe, struct mtk_foe_entry *entry,
>   	wmb();
>   	hwe->ib1 = entry->ib1;
>   
> +	if (ppe->accounting) {
> +		int type;
> +
> +		type = FIELD_GET(MTK_FOE_IB1_PACKET_TYPE, entry->ib1);
> +		if (type >= MTK_PPE_PKT_TYPE_IPV4_DSLITE)
> +			hwe->ipv6.ib2 |= MTK_FOE_IB2_MIB_CNT;
> +		else
> +			hwe->ipv4.ib2 |= MTK_FOE_IB2_MIB_CNT;
> +	}
Use mtk_foe_entry_ib2() here.

> @@ -654,11 +711,8 @@ void __mtk_ppe_check_skb(struct mtk_ppe *ppe, struct sk_buff *skb, u16 hash)
>   			continue;
>   		}
>   
> -		if (found || !mtk_flow_entry_match(ppe->eth, entry, hwe)) {
> -			if (entry->hash != 0xffff)
> -				entry->hash = 0xffff;
> +		if (found || !mtk_flow_entry_match(ppe->eth, entry, hwe))
>   			continue;
> -		}
What is the reason for this change?

- Felix