[PATCH net-next 6/6] net: macb: Add MACB_CAPS_QBV capability flag for IEEE 802.1Qbv support

[Vineeth Karumanchi]

The "exclude_qbv" bit in designcfg_debug1 register varies between MACB/GEM
IP revisions, making direct register probing unreliable for
feature detection. A capability-based approach provides consistent
QBV support identification across the IP family

Platform support:
- Enable MACB_CAPS_QBV for Xilinx Versal platform configuration
- Foundation for QBV feature detection in TAPRIO implementation

Signed-off-by: Vineeth Karumanchi <vineeth.karumanchi@xxxxxxx>
---
 drivers/net/ethernet/cadence/macb.h      | 1 +
 drivers/net/ethernet/cadence/macb_main.c | 6 +++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index ef3995564c5c..4e8d5dcc814e 100644
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -782,6 +782,7 @@
 #define MACB_CAPS_MIIONRGMII			0x00000200
 #define MACB_CAPS_NEED_TSUCLK			0x00000400
 #define MACB_CAPS_QUEUE_DISABLE			0x00000800
+#define MACB_CAPS_QBV				0x00001000
 #define MACB_CAPS_PCS				0x01000000
 #define MACB_CAPS_HIGH_SPEED			0x02000000
 #define MACB_CAPS_CLK_HW_CHG			0x04000000
diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index cc33491930e3..98e56697661c 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -4601,6 +4601,10 @@ static int macb_init(struct platform_device *pdev)
 		dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
 	if (bp->caps & MACB_CAPS_SG_DISABLED)
 		dev->hw_features &= ~NETIF_F_SG;
+	/* Enable HW_TC if hardware supports QBV */
+	if (bp->caps & MACB_CAPS_QBV)
+		dev->hw_features |= NETIF_F_HW_TC;
+
 	dev->features = dev->hw_features;
 
 	/* Check RX Flow Filters support.
@@ -5345,7 +5349,7 @@ static const struct macb_config sama7g5_emac_config = {
 static const struct macb_config versal_config = {
 	.caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_JUMBO |
 		MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH | MACB_CAPS_NEED_TSUCLK |
-		MACB_CAPS_QUEUE_DISABLE,
+		MACB_CAPS_QUEUE_DISABLE, MACB_CAPS_QBV,
 	.dma_burst_length = 16,
 	.clk_init = macb_clk_init,
 	.init = init_reset_optional,
-- 
2.34.1