[PATCH net-next v2 2/3] net: stmmac: xgmac: Correct supported speed modes

From: Rohan G Thomas via B4 Relay
Date: Fri Aug 15 2025 - 13:00:12 EST


From: Rohan G Thomas <rohan.g.thomas@xxxxxxxxxx>

Correct supported speed modes as per the XGMAC databook.
Commit 9cb54af214a7 ("net: stmmac: Fix IP-cores specific
MAC capabilities") removes support for 10M, 100M and
1000HD. 1000HD is not supported by XGMAC IP, but it does
support 10M and 100M FD mode for XGMAC version >= 2_20,
and it also supports 10M and 100M HD mode if the HDSEL bit
is set in the MAC_HW_FEATURE0 reg. This commit enables support
for 10M and 100M speed modes for XGMAC IP based on XGMAC
version and MAC capabilities.

Fixes: 9cb54af214a7 ("net: stmmac: Fix IP-cores specific MAC capabilities")
Signed-off-by: Rohan G Thomas <rohan.g.thomas@xxxxxxxxxx>
Reviewed-by: Matthew Gerlach <matthew.gerlach@xxxxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c | 13 +++++++++++--
drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c | 5 +++++
2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
index 6cadf8de4fdfdb18af1a112b883b3d33a53da638..00e929bf280baec7aa8d2a75fc5ceea4a52c9979 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
@@ -49,6 +49,14 @@ static void dwxgmac2_core_init(struct mac_device_info *hw,
writel(XGMAC_INT_DEFAULT_EN, ioaddr + XGMAC_INT_EN);
}

+static void dwxgmac2_update_caps(struct stmmac_priv *priv)
+{
+ if (!priv->dma_cap.mbps_10_100)
+ priv->hw->link.caps &= ~(MAC_10 | MAC_100);
+ else if (!priv->dma_cap.half_duplex)
+ priv->hw->link.caps &= ~(MAC_10HD | MAC_100HD);
+}
+
static void dwxgmac2_set_mac(void __iomem *ioaddr, bool enable)
{
u32 tx = readl(ioaddr + XGMAC_TX_CONFIG);
@@ -1424,6 +1432,7 @@ static void dwxgmac2_set_arp_offload(struct mac_device_info *hw, bool en,

const struct stmmac_ops dwxgmac210_ops = {
.core_init = dwxgmac2_core_init,
+ .update_caps = dwxgmac2_update_caps,
.set_mac = dwxgmac2_set_mac,
.rx_ipc = dwxgmac2_rx_ipc,
.rx_queue_enable = dwxgmac2_rx_queue_enable,
@@ -1532,8 +1541,8 @@ int dwxgmac2_setup(struct stmmac_priv *priv)
mac->mcast_bits_log2 = ilog2(mac->multicast_filter_bins);

mac->link.caps = MAC_ASYM_PAUSE | MAC_SYM_PAUSE |
- MAC_1000FD | MAC_2500FD | MAC_5000FD |
- MAC_10000FD;
+ MAC_10 | MAC_100 | MAC_1000FD |
+ MAC_2500FD | MAC_5000FD | MAC_10000FD;
mac->link.duplex = 0;
mac->link.speed10 = XGMAC_CONFIG_SS_10_MII;
mac->link.speed100 = XGMAC_CONFIG_SS_100_MII;
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
index 7201a38842651a865493fce0cefe757d6ae9bafa..18e92b3c6df4200c51ee56f923158e3ae1cf5ef8 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
@@ -384,6 +384,9 @@ static int dwxgmac2_get_hw_feature(void __iomem *ioaddr,
{
u32 hw_cap;

+ struct stmmac_priv *priv = container_of(dma_cap, struct stmmac_priv,
+ dma_cap);
+
/* MAC HW feature 0 */
hw_cap = readl(ioaddr + XGMAC_HW_FEATURE0);
dma_cap->edma = (hw_cap & XGMAC_HWFEAT_EDMA) >> 31;
@@ -406,6 +409,8 @@ static int dwxgmac2_get_hw_feature(void __iomem *ioaddr,
dma_cap->vlhash = (hw_cap & XGMAC_HWFEAT_VLHASH) >> 4;
dma_cap->half_duplex = (hw_cap & XGMAC_HWFEAT_HDSEL) >> 3;
dma_cap->mbps_1000 = (hw_cap & XGMAC_HWFEAT_GMIISEL) >> 1;
+ if (dma_cap->mbps_1000 && priv->synopsys_id >= DWXGMAC_CORE_2_20)
+ dma_cap->mbps_10_100 = 1;

/* MAC HW feature 1 */
hw_cap = readl(ioaddr + XGMAC_HW_FEATURE1);

--
2.32.0