net: stmmac: xgmac3+: Add support for Frame Preemption

Adds the HW specific support for Frame Preemption on XGMAC3+ cores.
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h

@@ -73,6 +73,9 @@
 #define XGMAC_RXQ_CTRL0			0x000000a0
 #define XGMAC_RXQEN(x)			GENMASK((x) * 2 + 1, (x) * 2)
 #define XGMAC_RXQEN_SHIFT(x)		((x) * 2)
+#define XGMAC_RXQ_CTRL1			0x000000a4
+#define XGMAC_RQ			GENMASK(7, 4)
+#define XGMAC_RQ_SHIFT			4
 #define XGMAC_RXQ_CTRL2			0x000000a8
 #define XGMAC_RXQ_CTRL3			0x000000ac
 #define XGMAC_PSRQ(x)			GENMASK((x) * 8 + 7, (x) * 8)
@@ -136,6 +139,7 @@
 #define XGMAC_HWFEAT_TXQCNT		GENMASK(9, 6)
 #define XGMAC_HWFEAT_RXQCNT		GENMASK(3, 0)
 #define XGMAC_HW_FEATURE3		0x00000128
+#define XGMAC_HWFEAT_FPESEL		BIT(26)
 #define XGMAC_HWFEAT_ESTWID		GENMASK(24, 23)
 #define XGMAC_HWFEAT_ESTDEP		GENMASK(22, 20)
 #define XGMAC_HWFEAT_ESTSEL		BIT(19)
@@ -151,6 +155,8 @@
 #define XGMAC_MDIO_ADDR			0x00000200
 #define XGMAC_MDIO_DATA			0x00000204
 #define XGMAC_MDIO_C22P			0x00000220
+#define XGMAC_FPE_CTRL_STS		0x00000280
+#define XGMAC_EFPE			BIT(0)
 #define XGMAC_ADDRx_HIGH(x)		(0x00000300 + (x) * 0x8)
 #define XGMAC_ADDR_MAX			32
 #define XGMAC_AE			BIT(31)

drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c

@@ -1410,6 +1410,29 @@ static int dwxgmac3_est_configure(void __iomem *ioaddr, struct stmmac_est *cfg,
 	return 0;
 }
 
+static void dwxgmac3_fpe_configure(void __iomem *ioaddr, u32 num_txq,
+				   u32 num_rxq, bool enable)
+{
+	u32 value;
+
+	if (!enable) {
+		value = readl(ioaddr + XGMAC_FPE_CTRL_STS);
+
+		value &= ~XGMAC_EFPE;
+
+		writel(value, ioaddr + XGMAC_FPE_CTRL_STS);
+	}
+
+	value = readl(ioaddr + XGMAC_RXQ_CTRL1);
+	value &= ~XGMAC_RQ;
+	value |= (num_rxq - 1) << XGMAC_RQ_SHIFT;
+	writel(value, ioaddr + XGMAC_RXQ_CTRL1);
+
+	value = readl(ioaddr + XGMAC_FPE_CTRL_STS);
+	value |= XGMAC_EFPE;
+	writel(value, ioaddr + XGMAC_FPE_CTRL_STS);
+}
+
 const struct stmmac_ops dwxgmac210_ops = {
 	.core_init = dwxgmac2_core_init,
 	.set_mac = dwxgmac2_set_mac,
@@ -1454,6 +1477,7 @@ const struct stmmac_ops dwxgmac210_ops = {
 	.config_l4_filter = dwxgmac2_config_l4_filter,
 	.set_arp_offload = dwxgmac2_set_arp_offload,
 	.est_configure = dwxgmac3_est_configure,
+	.fpe_configure = dwxgmac3_fpe_configure,
 };
 
 int dwxgmac2_setup(struct stmmac_priv *priv)

drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c

@@ -429,6 +429,7 @@ static void dwxgmac2_get_hw_feature(void __iomem *ioaddr,
 
 	/* MAC HW feature 3 */
 	hw_cap = readl(ioaddr + XGMAC_HW_FEATURE3);
+	dma_cap->fpesel = (hw_cap & XGMAC_HWFEAT_FPESEL) >> 26;
 	dma_cap->estwid = (hw_cap & XGMAC_HWFEAT_ESTWID) >> 23;
 	dma_cap->estdep = (hw_cap & XGMAC_HWFEAT_ESTDEP) >> 20;
 	dma_cap->estsel = (hw_cap & XGMAC_HWFEAT_ESTSEL) >> 19;