[PATCH net-next v2 13/15] net: stmmac: add helper to set transmit tail pointer
From: Russell King (Oracle) <hidden>
Date: 2026-03-12 10:10:10
Also in:
bpf, netdev
Subsystem:
networking drivers, stmmac ethernet driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Setting the queue transmit tail pointer follows a common pattern: calculate the DMA address, and then call stmmac_set_tx_tail_ptr(). The only difference between all the call sites is the index used. Factor this out into a static function. We need to update dwmac4_display_ring() to cope the passed head pointer always pointing at the struct dma_desc by using dma_desc_to_edesc() to convert it to struct dma_edesc. This is the only stmmac_display_ring() implementation that this affects. Signed-off-by: Russell King (Oracle) <redacted> --- .../ethernet/stmicro/stmmac/dwmac4_descs.c | 2 +- .../net/ethernet/stmicro/stmmac/stmmac_main.c | 30 ++++++++++--------- 2 files changed, 17 insertions(+), 15 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
index 1bbf02504dad..d5c003f3fbbc 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c@@ -427,7 +427,7 @@ static void dwmac4_display_ring(void *head, unsigned int size, bool rx, extp++; } } else if (desc_size == sizeof(struct dma_edesc)) { - struct dma_edesc *ep = (struct dma_edesc *)head; + struct dma_edesc *ep = dma_desc_to_edesc(head); for (i = 0; i < size; i++) { dma_addr = dma_rx_phy + i * sizeof(*ep);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index da1726b887f3..4521469c5e1d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c@@ -385,6 +385,18 @@ static struct dma_desc *stmmac_get_tx_desc(struct stmmac_priv *priv, return &tx_q->dma_tx[index]; } +static void stmmac_set_queue_tx_tail_ptr(struct stmmac_priv *priv, + struct stmmac_tx_queue *tx_q, + unsigned int chan, unsigned int index) +{ + int desc_size; + + desc_size = stmmac_get_tx_desc_size(priv, tx_q); + + tx_q->tx_tail_addr = tx_q->dma_tx_phy + index * desc_size; + stmmac_set_tx_tail_ptr(priv, priv->ioaddr, tx_q->tx_tail_addr, chan); +} + static size_t stmmac_get_rx_desc_size(struct stmmac_priv *priv) { if (priv->extend_desc)
@@ -3311,9 +3323,7 @@ static int stmmac_init_dma_engine(struct stmmac_priv *priv) stmmac_init_tx_chan(priv, priv->ioaddr, priv->plat->dma_cfg, tx_q->dma_tx_phy, chan); - tx_q->tx_tail_addr = tx_q->dma_tx_phy; - stmmac_set_tx_tail_ptr(priv, priv->ioaddr, - tx_q->tx_tail_addr, chan); + stmmac_set_queue_tx_tail_ptr(priv, tx_q, chan, 0); } return ret;
@@ -4326,9 +4336,6 @@ static void stmmac_tso_allocator(struct stmmac_priv *priv, dma_addr_t des, static void stmmac_flush_tx_descriptors(struct stmmac_priv *priv, int queue) { struct stmmac_tx_queue *tx_q = &priv->dma_conf.tx_queue[queue]; - int desc_size; - - desc_size = stmmac_get_tx_desc_size(priv, tx_q); /* The own bit must be the latest setting done when prepare the * descriptor and then barrier is needed to make sure that
@@ -4336,8 +4343,7 @@ static void stmmac_flush_tx_descriptors(struct stmmac_priv *priv, int queue) */ wmb(); - tx_q->tx_tail_addr = tx_q->dma_tx_phy + (tx_q->cur_tx * desc_size); - stmmac_set_tx_tail_ptr(priv, priv->ioaddr, tx_q->tx_tail_addr, queue); + stmmac_set_queue_tx_tail_ptr(priv, tx_q, queue, tx_q->cur_tx); } /**
@@ -6967,9 +6973,7 @@ void stmmac_enable_tx_queue(struct stmmac_priv *priv, u32 queue) if (tx_q->tbs & STMMAC_TBS_AVAIL) stmmac_enable_tbs(priv, priv->ioaddr, 1, tx_q->queue_index); - tx_q->tx_tail_addr = tx_q->dma_tx_phy; - stmmac_set_tx_tail_ptr(priv, priv->ioaddr, - tx_q->tx_tail_addr, tx_q->queue_index); + stmmac_set_queue_tx_tail_ptr(priv, tx_q, tx_q->queue_index, 0); stmmac_start_tx_dma(priv, queue);
@@ -7070,9 +7074,7 @@ int stmmac_xdp_open(struct net_device *dev) stmmac_init_tx_chan(priv, priv->ioaddr, priv->plat->dma_cfg, tx_q->dma_tx_phy, chan); - tx_q->tx_tail_addr = tx_q->dma_tx_phy; - stmmac_set_tx_tail_ptr(priv, priv->ioaddr, - tx_q->tx_tail_addr, chan); + stmmac_set_queue_tx_tail_ptr(priv, tx_q, chan, 0); hrtimer_setup(&tx_q->txtimer, stmmac_tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); }
--
2.47.3