[PATCH 4/5] net: ftgmac100: Add AST2700 upper DMA address support
flat view
COLD17d
SUPERSEDED
From: Jacky Chou <jacky_chou@aspeedtech.com>
Date: 2026-09-27 07:17:32
Also in:
linux-devicetree, lkml
Subsystem:
networking drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Revision v1 of 3 in this series.
Revisions (3)
- v1 current
- v2 [diff vs current]
- v3 [diff vs current]
Program the high RX and TX descriptor ring base registers and carry the upper DMA address bits in RX and TX descriptors. Rebuild full buffer DMA addresses in a 64-bit type before unmapping them so bits 34:32 are not lost to 32-bit arithmetic. The descriptor format provides three upper buffer address bits, so request a 35-bit DMA mask instead of advertising an address range that the hardware cannot encode. Gate all extended address handling with a match-data quirk so older register layouts remain untouched and later compatible controllers can opt into the same capability. Signed-off-by: Jacky Chou <jacky_chou@aspeedtech.com> --- drivers/net/ethernet/faraday/ftgmac100.c | 62 +++++++++++++++++++++++++++----- drivers/net/ethernet/faraday/ftgmac100.h | 6 ++++ 2 files changed, 59 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
index b835472da360..4becd28f805b 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c@@ -8,6 +8,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/bitfield.h> #include <linux/clk.h> #include <linux/reset.h> #include <linux/dma-mapping.h>
@@ -42,6 +43,7 @@ enum ftgmac100_mac_id { }; #define FTGMAC100_QUIRK_RMII_ENABLE BIT(0) +#define FTGMAC100_QUIRK_DMA_35BIT BIT(1) struct ftgmac100_match_data { enum ftgmac100_mac_id mac_id;
@@ -303,10 +305,16 @@ static void ftgmac100_init_hw(struct ftgmac100 *priv) iowrite32(reg, priv->base + FTGMAC100_OFFSET_ISR); /* Setup RX ring buffer base */ - iowrite32(priv->rxdes_dma, priv->base + FTGMAC100_OFFSET_RXR_BADR); + iowrite32(lower_32_bits(priv->rxdes_dma), priv->base + FTGMAC100_OFFSET_RXR_BADR); + if (priv->quirks & FTGMAC100_QUIRK_DMA_35BIT) + iowrite32(upper_32_bits(priv->rxdes_dma), + priv->base + FTGMAC100_OFFSET_RXR_BADDR_HIGH); /* Setup TX ring buffer base */ - iowrite32(priv->txdes_dma, priv->base + FTGMAC100_OFFSET_NPTXR_BADR); + iowrite32(lower_32_bits(priv->txdes_dma), priv->base + FTGMAC100_OFFSET_NPTXR_BADR); + if (priv->quirks & FTGMAC100_QUIRK_DMA_35BIT) + iowrite32(upper_32_bits(priv->txdes_dma), + priv->base + FTGMAC100_OFFSET_TXR_BADDR_HIGH); /* Configure RX buffer size */ iowrite32(FTGMAC100_RBSR_SIZE(RX_BUF_SIZE),
@@ -469,7 +477,10 @@ static int ftgmac100_alloc_rx_buf(struct ftgmac100 *priv, unsigned int entry, priv->rx_skbs[entry] = skb; /* Store DMA address into RX desc */ - rxdes->rxdes3 = cpu_to_le32(map); + if (priv->quirks & FTGMAC100_QUIRK_DMA_35BIT) + rxdes->rxdes2 = cpu_to_le32(FIELD_PREP(FTGMAC100_RXDES2_RXBUF_BADR_HI, + upper_32_bits(map))); + rxdes->rxdes3 = cpu_to_le32(lower_32_bits(map)); /* Ensure the above is ordered vs clearing the OWN bit */ dma_wmb();
@@ -596,6 +607,9 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed) /* Tear down DMA mapping, do necessary cache management */ map = le32_to_cpu(rxdes->rxdes3); + if (priv->quirks & FTGMAC100_QUIRK_DMA_35BIT) + map |= (u64)FIELD_GET(FTGMAC100_RXDES2_RXBUF_BADR_HI, + le32_to_cpu(rxdes->rxdes2)) << 32; #if defined(CONFIG_ARM) && !defined(CONFIG_ARM_DMA_USE_IOMMU) /* When we don't have an iommu, we can save cycles by not
@@ -672,9 +686,14 @@ static void ftgmac100_free_tx_packet(struct ftgmac100 *priv, struct ftgmac100_txdes *txdes, u32 ctl_stat) { - dma_addr_t map = le32_to_cpu(txdes->txdes3); + dma_addr_t map; size_t len; + map = le32_to_cpu(txdes->txdes3); + if (priv->quirks & FTGMAC100_QUIRK_DMA_35BIT) + map |= (u64)FIELD_GET(FTGMAC100_TXDES2_TXBUF_BADR_HI, + le32_to_cpu(txdes->txdes2)) << 32; + if (ctl_stat & FTGMAC100_TXDES0_FTS) { len = skb_headlen(skb); dma_unmap_single(priv->dev, map, len, DMA_TO_DEVICE);
@@ -828,7 +847,10 @@ static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb, f_ctl_stat |= FTGMAC100_TXDES0_FTS; if (nfrags == 0) f_ctl_stat |= FTGMAC100_TXDES0_LTS; - txdes->txdes3 = cpu_to_le32(map); + if (priv->quirks & FTGMAC100_QUIRK_DMA_35BIT) + txdes->txdes2 = cpu_to_le32(FIELD_PREP(FTGMAC100_TXDES2_TXBUF_BADR_HI, + upper_32_bits(map))); + txdes->txdes3 = cpu_to_le32(lower_32_bits(map)); txdes->txdes1 = cpu_to_le32(csum_vlan); /* Next descriptor */
@@ -856,7 +878,10 @@ static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb, ctl_stat |= FTGMAC100_TXDES0_LTS; txdes->txdes0 = cpu_to_le32(ctl_stat); txdes->txdes1 = 0; - txdes->txdes3 = cpu_to_le32(map); + if (priv->quirks & FTGMAC100_QUIRK_DMA_35BIT) + txdes->txdes2 = cpu_to_le32(FIELD_PREP(FTGMAC100_TXDES2_TXBUF_BADR_HI, + upper_32_bits(map))); + txdes->txdes3 = cpu_to_le32(lower_32_bits(map)); /* Next one */ pointer = ftgmac100_next_tx_pointer(priv, pointer);
@@ -931,7 +956,12 @@ static void ftgmac100_free_buffers(struct ftgmac100 *priv) for (i = 0; i < priv->rx_q_entries; i++) { struct ftgmac100_rxdes *rxdes = &priv->rxdes[i]; struct sk_buff *skb = priv->rx_skbs[i]; - dma_addr_t map = le32_to_cpu(rxdes->rxdes3); + dma_addr_t map; + + map = le32_to_cpu(rxdes->rxdes3); + if (priv->quirks & FTGMAC100_QUIRK_DMA_35BIT) + map |= (u64)FIELD_GET(FTGMAC100_RXDES2_RXBUF_BADR_HI, + le32_to_cpu(rxdes->rxdes2)) << 32; if (!skb) continue;
@@ -1050,7 +1080,12 @@ static void ftgmac100_init_rings(struct ftgmac100 *priv) for (i = 0; i < priv->rx_q_entries; i++) { rxdes = &priv->rxdes[i]; rxdes->rxdes0 = 0; - rxdes->rxdes3 = cpu_to_le32(priv->rx_scratch_dma); + if (priv->quirks & FTGMAC100_QUIRK_DMA_35BIT) { + u32 hi = upper_32_bits(priv->rx_scratch_dma); + + rxdes->rxdes2 = cpu_to_le32(FIELD_PREP(FTGMAC100_RXDES2_RXBUF_BADR_HI, hi)); + } + rxdes->rxdes3 = cpu_to_le32(lower_32_bits(priv->rx_scratch_dma)); } /* Mark the end of the ring */ rxdes->rxdes0 |= cpu_to_le32(priv->rxdes0_edorr_mask);
@@ -2094,6 +2129,14 @@ static int ftgmac100_probe(struct platform_device *pdev) netdev->hw_features &= ~(NETIF_F_HW_CSUM | NETIF_F_RXCSUM); netdev->features |= netdev->hw_features; + if (priv->quirks & FTGMAC100_QUIRK_DMA_35BIT) { + err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(35)); + if (err) { + dev_err(&pdev->dev, "35-bit DMA enable failed\n"); + goto err; + } + } + /* register network device */ err = register_netdev(netdev); if (err) {
@@ -2146,7 +2189,8 @@ static const struct ftgmac100_match_data ftgmac100_match_data_ast2600 = { static const struct ftgmac100_match_data ftgmac100_match_data_ast2700 = { .mac_id = FTGMAC100_AST2700, - .quirks = FTGMAC100_QUIRK_RMII_ENABLE, + .quirks = FTGMAC100_QUIRK_RMII_ENABLE | + FTGMAC100_QUIRK_DMA_35BIT, }; static const struct ftgmac100_match_data ftgmac100_match_data_faraday = {
diff --git a/drivers/net/ethernet/faraday/ftgmac100.h b/drivers/net/ethernet/faraday/ftgmac100.h
index 8c35c895b146..0c244b1c0a35 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.h
+++ b/drivers/net/ethernet/faraday/ftgmac100.h@@ -57,6 +57,9 @@ #define FTGMAC100_OFFSET_RX_RUNT 0xc0 #define FTGMAC100_OFFSET_RX_CRCER_FTL 0xc4 #define FTGMAC100_OFFSET_RX_COL_LOST 0xc8 +/* reserved 0xcc - 0x178 */ +#define FTGMAC100_OFFSET_TXR_BADDR_HIGH 0x17c +#define FTGMAC100_OFFSET_RXR_BADDR_HIGH 0x18c /* * Interrupt status register & interrupt enable register
@@ -226,6 +229,7 @@ struct ftgmac100_txdes { #define FTGMAC100_TXDES1_TX2FIC (1 << 30) #define FTGMAC100_TXDES1_TXIC (1 << 31) +#define FTGMAC100_TXDES2_TXBUF_BADR_HI GENMASK(18, 16) /* * Receive descriptor, aligned to 16 bytes */
@@ -272,4 +276,6 @@ struct ftgmac100_rxdes { #define FTGMAC100_RXDES1_UDP_CHKSUM_ERR (1 << 26) #define FTGMAC100_RXDES1_IP_CHKSUM_ERR (1 << 27) +#define FTGMAC100_RXDES2_RXBUF_BADR_HI GENMASK(18, 16) + #endif /* __FTGMAC100_H */
--
2.34.1