[PATCH v2 net-next 03/15] net: ethernet: mtk_eth_soc: move tx dma desc configuration in mtk_tx_set_dma_desc

Lorenzo Bianconi
2022-05-16T16:08:01Z

Move tx dma descriptor configuration in mtk_tx_set_dma_desc routine.
This is a preliminary patch to introduce mt7986 ethernet support since
it relies on a different tx dma descriptor layout.

Tested-by: Sam Shih <sam.shih@mediatek.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
drivers/net/ethernet/mediatek/mtk_eth_soc.c | 105 +++++++++++---------
drivers/net/ethernet/mediatek/mtk_eth_soc.h | 11 ++
2 files changed, 67 insertions(+), 49 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 31c5da5d6b72..085c740779de 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -918,18 +918,51 @@ static void setup_tx_buf(struct mtk_eth *eth, struct mtk_tx_buf *tx_buf,
}
}

+static void mtk_tx_set_dma_desc(struct net_device *dev, struct mtk_tx_dma *desc,
+ struct mtk_tx_dma_desc_info *info)
+{
+ struct mtk_mac *mac = netdev_priv(dev);
+ u32 data;
+
+ WRITE_ONCE(desc->txd1, info->addr);
+
+ data = TX_DMA_SWC | TX_DMA_PLEN0(info->size);
+ if (info->last)
+ data |= TX_DMA_LS0;
+ WRITE_ONCE(desc->txd3, data);
+
+ data = (mac->id + 1) << TX_DMA_FPORT_SHIFT; /* forward port */
+ if (info->first) {
+ if (info->gso)
+ data |= TX_DMA_TSO;
+ /* tx checksum offload */
+ if (info->csum)
+ data |= TX_DMA_CHKSUM;
+ /* vlan header offload */
+ if (info->vlan)
+ data |= TX_DMA_INS_VLAN | info->vlan_tci;
+ }
+ WRITE_ONCE(desc->txd4, data);
+}
+
static int mtk_tx_map(struct sk_buff *skb, struct net_device *dev,
int tx_num, struct mtk_tx_ring *ring, bool gso)
{
+ struct mtk_tx_dma_desc_info txd_info = {
+ .size = skb_headlen(skb),
+ .gso = gso,
+ .csum = skb->ip_summed == CHECKSUM_PARTIAL,
+ .vlan = skb_vlan_tag_present(skb),
+ .vlan_tci = skb_vlan_tag_get(skb),
+ .first = true,
+ .last = !skb_is_nonlinear(skb),
+ };
struct mtk_mac *mac = netdev_priv(dev);
struct mtk_eth *eth = mac->hw;
struct mtk_tx_dma *itxd, *txd;
struct mtk_tx_dma *itxd_pdma, *txd_pdma;
struct mtk_tx_buf *itx_buf, *tx_buf;
- dma_addr_t mapped_addr;
- unsigned int nr_frags;
int i, n_desc = 1;
- u32 txd4 = 0, fport;
int k = 0;

itxd = ring->next_free;
@@ -937,49 +970,32 @@ static int mtk_tx_map(struct sk_buff *skb, struct net_device *dev,
if (itxd == ring->last_free)
return -ENOMEM;

- /* set the forward port */
- fport = (mac->id + 1) << TX_DMA_FPORT_SHIFT;
- txd4 |= fport;
-
itx_buf = mtk_desc_to_tx_buf(ring, itxd);
memset(itx_buf, 0, sizeof(*itx_buf));

- if (gso)
- txd4 |= TX_DMA_TSO;
-
- /* TX Checksum offload */
- if (skb->ip_summed == CHECKSUM_PARTIAL)
- txd4 |= TX_DMA_CHKSUM;
-
- /* VLAN header offload */
- if (skb_vlan_tag_present(skb))
- txd4 |= TX_DMA_INS_VLAN | skb_vlan_tag_get(skb);
-
- mapped_addr = dma_map_single(eth->dma_dev, skb->data,
- skb_headlen(skb), DMA_TO_DEVICE);
- if (unlikely(dma_mapping_error(eth->dma_dev, mapped_addr)))
+ txd_info.addr = dma_map_single(eth->dma_dev, skb->data, txd_info.size,
+ DMA_TO_DEVICE);
+ if (unlikely(dma_mapping_error(eth->dma_dev, txd_info.addr)))
return -ENOMEM;

- WRITE_ONCE(itxd->txd1, mapped_addr);
+ mtk_tx_set_dma_desc(dev, itxd, &txd_info);
+
itx_buf->flags |= MTK_TX_FLAGS_SINGLE0;
itx_buf->flags |= (!mac->id) ? MTK_TX_FLAGS_FPORT0 :
MTK_TX_FLAGS_FPORT1;
- setup_tx_buf(eth, itx_buf, itxd_pdma, mapped_addr, skb_headlen(skb),
+ setup_tx_buf(eth, itx_buf, itxd_pdma, txd_info.addr, txd_info.size,
k++);

/* TX SG offload */
txd = itxd;
txd_pdma = qdma_to_pdma(ring, txd);
- nr_frags = skb_shinfo(skb)->nr_frags;

- for (i = 0; i < nr_frags; i++) {
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
unsigned int offset = 0;
int frag_size = skb_frag_size(frag);

while (frag_size) {
- bool last_frag = false;
- unsigned int frag_map_size;
bool new_desc = true;

if (MTK_HAS_CAPS(eth->soc->caps, MTK_QDMA) ||
@@ -994,23 +1010,17 @@ static int mtk_tx_map(struct sk_buff *skb, struct net_device *dev,
new_desc = false;
}

-
- frag_map_size = min(frag_size, MTK_TX_DMA_BUF_LEN);
- mapped_addr = skb_frag_dma_map(eth->dma_dev, frag, offset,
- frag_map_size,
- DMA_TO_DEVICE);
- if (unlikely(dma_mapping_error(eth->dma_dev, mapped_addr)))
+ memset(&txd_info, 0, sizeof(struct mtk_tx_dma_desc_info));
+ txd_info.size = min(frag_size, MTK_TX_DMA_BUF_LEN);
+ txd_info.last = i == skb_shinfo(skb)->nr_frags - 1 &&
+ !(frag_size - txd_info.size);
+ txd_info.addr = skb_frag_dma_map(eth->dma_dev, frag,
+ offset, txd_info.size,
+ DMA_TO_DEVICE);
+ if (unlikely(dma_mapping_error(eth->dma_dev, txd_info.addr)))
goto err_dma;

- if (i == nr_frags - 1 &&
- (frag_size - frag_map_size) == 0)
- last_frag = true;
-
- WRITE_ONCE(txd->txd1, mapped_addr);
- WRITE_ONCE(txd->txd3, (TX_DMA_SWC |
- TX_DMA_PLEN0(frag_map_size) |
- last_frag * TX_DMA_LS0));
- WRITE_ONCE(txd->txd4, fport);
+ mtk_tx_set_dma_desc(dev, txd, &txd_info);

tx_buf = mtk_desc_to_tx_buf(ring, txd);
if (new_desc)
@@ -1020,20 +1030,17 @@ static int mtk_tx_map(struct sk_buff *skb, struct net_device *dev,
tx_buf->flags |= (!mac->id) ? MTK_TX_FLAGS_FPORT0 :
MTK_TX_FLAGS_FPORT1;

- setup_tx_buf(eth, tx_buf, txd_pdma, mapped_addr,
- frag_map_size, k++);
+ setup_tx_buf(eth, tx_buf, txd_pdma, txd_info.addr,
+ txd_info.size, k++);

- frag_size -= frag_map_size;
- offset += frag_map_size;
+ frag_size -= txd_info.size;
+ offset += txd_info.size;
}
}

/* store skb to cleanup */
itx_buf->skb = skb;

- WRITE_ONCE(itxd->txd4, txd4);
- WRITE_ONCE(itxd->txd3, (TX_DMA_SWC | TX_DMA_PLEN0(skb_headlen(skb)) |
- (!nr_frags * TX_DMA_LS0)));
if (!MTK_HAS_CAPS(eth->soc->caps, MTK_QDMA)) {
if (k & 0x1)
txd_pdma->txd2 |= TX_DMA_LS0;
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
index b04977fa84f6..5d940315c7ba 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -844,6 +844,17 @@ enum mkt_eth_capabilities {
MTK_MUX_U3_GMAC2_TO_QPHY | \
MTK_MUX_GMAC12_TO_GEPHY_SGMII | MTK_QDMA)

+struct mtk_tx_dma_desc_info {
+ dma_addr_t addr;
+ u32 size;
+ u16 vlan_tci;
+ u8 gso:1;
+ u8 csum:1;
+ u8 vlan:1;
+ u8 first:1;
+ u8 last:1;
+};
+
/* struct mtk_eth_data - This is the structure holding all differences
* among various plaforms
* @ana_rgc3: The offset for register ANA_RGC3 related to
--
2.35.3