openwrt/target/linux/generic/pending-5.4/770-08-net-ethernet-mtk_eth_soc-cache-hardware-pointer-of-l.patch
Felix Fietkau f0cc5f6c0a ramips/mediatek: improve GRO performance, fix PPE packet parsing
Backport upstream changes to initialize GDM settings and reset PPE
Allow GMAC to recognize the special tag to fix PPE packet parsing
Improve GRO performance by passing PPE L4 hash as skb hash

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2020-09-13 11:14:32 +02:00

68 lines
2.3 KiB
Diff

From: Felix Fietkau <nbd@nbd.name>
Date: Thu, 27 Aug 2020 06:32:03 +0200
Subject: [PATCH] net: ethernet: mtk_eth_soc: cache hardware pointer of last
freed tx descriptor
The value is only updated by the CPU, so it is cheaper to access from the ring
data structure than from a hardware register
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -1358,7 +1358,7 @@ static int mtk_poll_tx_qdma(struct mtk_e
struct mtk_tx_buf *tx_buf;
u32 cpu, dma;
- cpu = mtk_r32(eth, MTK_QTX_CRX_PTR);
+ cpu = ring->last_free_ptr;
dma = mtk_r32(eth, MTK_QTX_DRX_PTR);
desc = mtk_qdma_phys_to_virt(ring, cpu);
@@ -1392,6 +1392,7 @@ static int mtk_poll_tx_qdma(struct mtk_e
cpu = next_cpu;
}
+ ring->last_free_ptr = cpu;
mtk_w32(eth, cpu, MTK_QTX_CRX_PTR);
return budget;
@@ -1592,6 +1593,7 @@ static int mtk_tx_alloc(struct mtk_eth *
atomic_set(&ring->free_count, MTK_DMA_SIZE - 2);
ring->next_free = &ring->dma[0];
ring->last_free = &ring->dma[MTK_DMA_SIZE - 1];
+ ring->last_free_ptr = (u32)(ring->phys + ((MTK_DMA_SIZE - 1) * sz));
ring->thresh = MAX_SKB_FRAGS;
/* make sure that all changes to the dma ring are flushed before we
@@ -1605,9 +1607,7 @@ static int mtk_tx_alloc(struct mtk_eth *
mtk_w32(eth,
ring->phys + ((MTK_DMA_SIZE - 1) * sz),
MTK_QTX_CRX_PTR);
- mtk_w32(eth,
- ring->phys + ((MTK_DMA_SIZE - 1) * sz),
- MTK_QTX_DRX_PTR);
+ mtk_w32(eth, ring->last_free_ptr, MTK_QTX_DRX_PTR);
mtk_w32(eth, (QDMA_RES_THRES << 8) | QDMA_RES_THRES,
MTK_QTX_CFG(0));
} else {
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -624,6 +624,7 @@ struct mtk_tx_buf {
* @phys: The physical addr of tx_buf
* @next_free: Pointer to the next free descriptor
* @last_free: Pointer to the last free descriptor
+ * @last_free_ptr: Hardware pointer value of the last free descriptor
* @thresh: The threshold of minimum amount of free descriptors
* @free_count: QDMA uses a linked list. Track how many free descriptors
* are present
@@ -634,6 +635,7 @@ struct mtk_tx_ring {
dma_addr_t phys;
struct mtk_tx_dma *next_free;
struct mtk_tx_dma *last_free;
+ u32 last_free_ptr;
u16 thresh;
atomic_t free_count;
int dma_size;