[PATCH net-next v2 12/12] net: ethernet: mtk_eth_soc: drop packets to WDMA if the ring is full

Felix Fietkau
2022-11-09T16:54:14Z

Improves handling of DMA ring overflow.
Clarify other WDMA drop related comment.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
drivers/net/ethernet/mediatek/mtk_eth_soc.c | 5 ++++-
drivers/net/ethernet/mediatek/mtk_eth_soc.h | 1 +
2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index a9a270317ff4..9aa4fa322794 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -3566,9 +3566,12 @@ static int mtk_hw_init(struct mtk_eth *eth)
mtk_w32(eth, 0x21021000, MTK_FE_INT_GRP);

if (MTK_HAS_CAPS(eth->soc->caps, MTK_NETSYS_V2)) {
- /* PSE should not drop port8 and port9 packets */
+ /* PSE should not drop port8 and port9 packets from WDMA Tx */
mtk_w32(eth, 0x00000300, PSE_DROP_CFG);

+ /* PSE should drop packets to port 8/9 on WDMA Rx ring full */
+ mtk_w32(eth, 0x00000300, PSE_PPE0_DROP);
+
/* PSE Free Queue Flow Control */
mtk_w32(eth, 0x01fa01f4, PSE_FQFC_CFG2);

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
index 60da6936559a..fb876d2a6ea1 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -127,6 +127,7 @@
#define PSE_FQFC_CFG1 0x100
#define PSE_FQFC_CFG2 0x104
#define PSE_DROP_CFG 0x108
+#define PSE_PPE0_DROP 0x110

/* PSE Input Queue Reservation Register*/
#define PSE_IQ_REV(x) (0x140 + (((x) - 1) << 2))
--
2.38.1