[11/14] net: ethernet: mtk_eth_soc: fix VLAN rx hardware acceleration
Commit Message
- enable VLAN untagging for PDMA rx
- make it possible to disable the feature via ethtool
- pass VLAN tag to the DSA driver
- untag special tag on PDMA only if no non-DSA devices are in use
- disable special tag untagging on 7986 for now, since it's not working yet
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
drivers/net/ethernet/mediatek/mtk_eth_soc.c | 36 +++++++++++++--------
drivers/net/ethernet/mediatek/mtk_eth_soc.h | 3 ++
2 files changed, 25 insertions(+), 14 deletions(-)
Comments
On Mon, Nov 07, 2022 at 07:54:49PM +0100, Felix Fietkau wrote:
> - enable VLAN untagging for PDMA rx
> - make it possible to disable the feature via ethtool
> - pass VLAN tag to the DSA driver
> - untag special tag on PDMA only if no non-DSA devices are in use
> - disable special tag untagging on 7986 for now, since it's not working yet
What is the downside of not enabling VLAN RX offloading, is it a
performance or a functional need to have it?
>
> Signed-off-by: Felix Fietkau <nbd@nbd.name>
> ---
> drivers/net/ethernet/mediatek/mtk_eth_soc.c | 36 +++++++++++++--------
> drivers/net/ethernet/mediatek/mtk_eth_soc.h | 3 ++
> 2 files changed, 25 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> index ab31dda2cd66..3b8995a483aa 100644
> --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> @@ -2015,16 +2015,9 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
> htons(RX_DMA_VPID(trxd.rxd4)),
> RX_DMA_VID(trxd.rxd4));
> } else if (trxd.rxd2 & RX_DMA_VTAG) {
> - __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
> + __vlan_hwaccel_put_tag(skb, htons(RX_DMA_VPID(trxd.rxd3)),
Why make this change? The network stack doesn't like it when you feed it
non-standard VLAN protocols, as you've noticed.
> RX_DMA_VID(trxd.rxd3));
> }
> -
> - /* If the device is attached to a dsa switch, the special
> - * tag inserted in VLAN field by hw switch can * be offloaded
> - * by RX HW VLAN offload. Clear vlan info.
What is the format of this special tag, what does it contain? The same
thing as what mtk_tag_rcv() parses?
> - */
> - if (netdev_uses_dsa(netdev))
> - __vlan_hwaccel_clear_tag(skb);
If the DSA switch information is present in the VLAN hwaccel, and the
VLAN hwaccel is cleared, and that up until this change,
NETIF_F_HW_VLAN_CTAG_RX was not configurable, it means that every
mtk_soc_data with MTK_HW_FEATURES would be broken as a DSA master?
> }
>
> skb_record_rx_queue(skb, 0);
> @@ -2847,15 +2840,17 @@ static netdev_features_t mtk_fix_features(struct net_device *dev,
>
> static int mtk_set_features(struct net_device *dev, netdev_features_t features)
> {
> - int err = 0;
> -
> - if (!((dev->features ^ features) & NETIF_F_LRO))
> - return 0;
> + struct mtk_mac *mac = netdev_priv(dev);
> + struct mtk_eth *eth = mac->hw;
> + netdev_features_t diff = dev->features ^ features;
>
> - if (!(features & NETIF_F_LRO))
> + if ((diff & NETIF_F_LRO) && !(features & NETIF_F_LRO))
> mtk_hwlro_netdev_disable(dev);
>
> - return err;
> + /* Set RX VLAN offloading */
> + mtk_w32(eth, !!(features & NETIF_F_HW_VLAN_CTAG_RX), MTK_CDMP_EG_CTRL);
Nit: do this only if (diff & NETIF_F_HW_VLAN_CTAG_RX).
> +
> + return 0;
> }
>
> /* wait for DMA to finish whatever it is doing before we start using it again */
> @@ -3176,6 +3171,15 @@ static int mtk_open(struct net_device *dev)
> else
> refcount_inc(ð->dma_refcnt);
>
> + /* Hardware special tag parsing needs to be disabled if at least
> + * one MAC does not use DSA.
> + */
Don't understand why, sorry.
> + if (!netdev_uses_dsa(dev)) {
> + u32 val = mtk_r32(eth, MTK_CDMP_IG_CTRL);
> + val &= ~MTK_CDMP_STAG_EN;
> + mtk_w32(eth, val, MTK_CDMP_IG_CTRL);
> + }
> +
> phylink_start(mac->phylink);
> netif_tx_start_all_queues(dev);
>
> @@ -3469,6 +3473,10 @@ static int mtk_hw_init(struct mtk_eth *eth)
> */
> val = mtk_r32(eth, MTK_CDMQ_IG_CTRL);
> mtk_w32(eth, val | MTK_CDMQ_STAG_EN, MTK_CDMQ_IG_CTRL);
> + if (MTK_HAS_CAPS(eth->soc->caps, MTK_NETSYS_V2)) {
> + val = mtk_r32(eth, MTK_CDMP_IG_CTRL);
> + mtk_w32(eth, val | MTK_CDMP_STAG_EN, MTK_CDMP_IG_CTRL);
> + }
>
> /* Enable RX VLan Offloading */
> mtk_w32(eth, 1, MTK_CDMP_EG_CTRL);
> diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
> index e09b2483c70c..26b2323185ef 100644
> --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
> +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
> @@ -93,6 +93,9 @@
> #define MTK_CDMQ_IG_CTRL 0x1400
> #define MTK_CDMQ_STAG_EN BIT(0)
>
> +/* CDMQ Exgress Control Register */
> +#define MTK_CDMQ_EG_CTRL 0x1404
> +
> /* CDMP Ingress Control Register */
> #define MTK_CDMP_IG_CTRL 0x400
> #define MTK_CDMP_STAG_EN BIT(0)
> --
> 2.38.1
>
On 08.11.22 00:32, Vladimir Oltean wrote:
> On Mon, Nov 07, 2022 at 07:54:49PM +0100, Felix Fietkau wrote:
>> - enable VLAN untagging for PDMA rx
>> - make it possible to disable the feature via ethtool
>> - pass VLAN tag to the DSA driver
>> - untag special tag on PDMA only if no non-DSA devices are in use
>> - disable special tag untagging on 7986 for now, since it's not working yet
>
> What is the downside of not enabling VLAN RX offloading, is it a
> performance or a functional need to have it?
>
>>
>> Signed-off-by: Felix Fietkau <nbd@nbd.name>
>> ---
>> drivers/net/ethernet/mediatek/mtk_eth_soc.c | 36 +++++++++++++--------
>> drivers/net/ethernet/mediatek/mtk_eth_soc.h | 3 ++
>> 2 files changed, 25 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
>> index ab31dda2cd66..3b8995a483aa 100644
>> --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
>> +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
>> @@ -2015,16 +2015,9 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
>> htons(RX_DMA_VPID(trxd.rxd4)),
>> RX_DMA_VID(trxd.rxd4));
>> } else if (trxd.rxd2 & RX_DMA_VTAG) {
>> - __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
>> + __vlan_hwaccel_put_tag(skb, htons(RX_DMA_VPID(trxd.rxd3)),
>
> Why make this change? The network stack doesn't like it when you feed it
> non-standard VLAN protocols, as you've noticed.
To make the hardware untag the DSA special tag, which is faster than
doing it in the DSA tag driver.
>> RX_DMA_VID(trxd.rxd3));
>> }
>> -
>> - /* If the device is attached to a dsa switch, the special
>> - * tag inserted in VLAN field by hw switch can * be offloaded
>> - * by RX HW VLAN offload. Clear vlan info.
>
> What is the format of this special tag, what does it contain? The same
> thing as what mtk_tag_rcv() parses?
Yes
>> - */
>> - if (netdev_uses_dsa(netdev))
>> - __vlan_hwaccel_clear_tag(skb);
>
> If the DSA switch information is present in the VLAN hwaccel, and the
> VLAN hwaccel is cleared, and that up until this change,
> NETIF_F_HW_VLAN_CTAG_RX was not configurable, it means that every
> mtk_soc_data with MTK_HW_FEATURES would be broken as a DSA master?Before my change, the hardware wasn't actually untagging packets with
the DSA special tag. Because of that, the code that I'm removing here
was never used.
>> }
>>
>> skb_record_rx_queue(skb, 0);
>> @@ -2847,15 +2840,17 @@ static netdev_features_t mtk_fix_features(struct net_device *dev,
>>
>> static int mtk_set_features(struct net_device *dev, netdev_features_t features)
>> {
>> - int err = 0;
>> -
>> - if (!((dev->features ^ features) & NETIF_F_LRO))
>> - return 0;
>> + struct mtk_mac *mac = netdev_priv(dev);
>> + struct mtk_eth *eth = mac->hw;
>> + netdev_features_t diff = dev->features ^ features;
>>
>> - if (!(features & NETIF_F_LRO))
>> + if ((diff & NETIF_F_LRO) && !(features & NETIF_F_LRO))
>> mtk_hwlro_netdev_disable(dev);
>>
>> - return err;
>> + /* Set RX VLAN offloading */
>> + mtk_w32(eth, !!(features & NETIF_F_HW_VLAN_CTAG_RX), MTK_CDMP_EG_CTRL);
>
> Nit: do this only if (diff & NETIF_F_HW_VLAN_CTAG_RX).
Will fix that in v2.
>
>> +
>> + return 0;
>> }
>>
>> /* wait for DMA to finish whatever it is doing before we start using it again */
>> @@ -3176,6 +3171,15 @@ static int mtk_open(struct net_device *dev)
>> else
>> refcount_inc(ð->dma_refcnt);
>>
>> + /* Hardware special tag parsing needs to be disabled if at least
>> + * one MAC does not use DSA.
>> + */
>
> Don't understand why, sorry.
The hardware has multiple ethernet MACs connected to the same DMA ring.
The parsing flag can't be turned off per MAC and it makes the hardware
assume that a DSA special tag is present.
>> + if (!netdev_uses_dsa(dev)) {
>> + u32 val = mtk_r32(eth, MTK_CDMP_IG_CTRL);
>> + val &= ~MTK_CDMP_STAG_EN;
>> + mtk_w32(eth, val, MTK_CDMP_IG_CTRL);
>> + }
>> +
>> phylink_start(mac->phylink);
>> netif_tx_start_all_queues(dev);
>>
- Felix
@@ -2015,16 +2015,9 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
htons(RX_DMA_VPID(trxd.rxd4)),
RX_DMA_VID(trxd.rxd4));
} else if (trxd.rxd2 & RX_DMA_VTAG) {
- __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
+ __vlan_hwaccel_put_tag(skb, htons(RX_DMA_VPID(trxd.rxd3)),
RX_DMA_VID(trxd.rxd3));
}
-
- /* If the device is attached to a dsa switch, the special
- * tag inserted in VLAN field by hw switch can * be offloaded
- * by RX HW VLAN offload. Clear vlan info.
- */
- if (netdev_uses_dsa(netdev))
- __vlan_hwaccel_clear_tag(skb);
}
skb_record_rx_queue(skb, 0);
@@ -2847,15 +2840,17 @@ static netdev_features_t mtk_fix_features(struct net_device *dev,
static int mtk_set_features(struct net_device *dev, netdev_features_t features)
{
- int err = 0;
-
- if (!((dev->features ^ features) & NETIF_F_LRO))
- return 0;
+ struct mtk_mac *mac = netdev_priv(dev);
+ struct mtk_eth *eth = mac->hw;
+ netdev_features_t diff = dev->features ^ features;
- if (!(features & NETIF_F_LRO))
+ if ((diff & NETIF_F_LRO) && !(features & NETIF_F_LRO))
mtk_hwlro_netdev_disable(dev);
- return err;
+ /* Set RX VLAN offloading */
+ mtk_w32(eth, !!(features & NETIF_F_HW_VLAN_CTAG_RX), MTK_CDMP_EG_CTRL);
+
+ return 0;
}
/* wait for DMA to finish whatever it is doing before we start using it again */
@@ -3176,6 +3171,15 @@ static int mtk_open(struct net_device *dev)
else
refcount_inc(ð->dma_refcnt);
+ /* Hardware special tag parsing needs to be disabled if at least
+ * one MAC does not use DSA.
+ */
+ if (!netdev_uses_dsa(dev)) {
+ u32 val = mtk_r32(eth, MTK_CDMP_IG_CTRL);
+ val &= ~MTK_CDMP_STAG_EN;
+ mtk_w32(eth, val, MTK_CDMP_IG_CTRL);
+ }
+
phylink_start(mac->phylink);
netif_tx_start_all_queues(dev);
@@ -3469,6 +3473,10 @@ static int mtk_hw_init(struct mtk_eth *eth)
*/
val = mtk_r32(eth, MTK_CDMQ_IG_CTRL);
mtk_w32(eth, val | MTK_CDMQ_STAG_EN, MTK_CDMQ_IG_CTRL);
+ if (MTK_HAS_CAPS(eth->soc->caps, MTK_NETSYS_V2)) {
+ val = mtk_r32(eth, MTK_CDMP_IG_CTRL);
+ mtk_w32(eth, val | MTK_CDMP_STAG_EN, MTK_CDMP_IG_CTRL);
+ }
/* Enable RX VLan Offloading */
mtk_w32(eth, 1, MTK_CDMP_EG_CTRL);
@@ -93,6 +93,9 @@
#define MTK_CDMQ_IG_CTRL 0x1400
#define MTK_CDMQ_STAG_EN BIT(0)
+/* CDMQ Exgress Control Register */
+#define MTK_CDMQ_EG_CTRL 0x1404
+
/* CDMP Ingress Control Register */
#define MTK_CDMP_IG_CTRL 0x400
#define MTK_CDMP_STAG_EN BIT(0)