net: stmmac: add support for dwmac 3.40a

dwmac 3.40a is an old ip version that can be found on SPEAr3xx soc.
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/dwmac-generic.c

@@ -71,6 +71,7 @@ static int dwmac_generic_probe(struct platform_device *pdev)
 
 static const struct of_device_id dwmac_generic_match[] = {
 	{ .compatible = "st,spear600-gmac"},
+	{ .compatible = "snps,dwmac-3.40a"},
 	{ .compatible = "snps,dwmac-3.50a"},
 	{ .compatible = "snps,dwmac-3.610"},
 	{ .compatible = "snps,dwmac-3.70a"},

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

@@ -508,6 +508,14 @@ stmmac_probe_config_dt(struct platform_device *pdev, u8 *mac)
 		plat->pmt = 1;
 	}
 
+	if (of_device_is_compatible(np, "snps,dwmac-3.40a")) {
+		plat->has_gmac = 1;
+		plat->enh_desc = 1;
+		plat->tx_coe = 1;
+		plat->bugged_jumbo = 1;
+		plat->pmt = 1;
+	}
+
 	if (of_device_is_compatible(np, "snps,dwmac-4.00") ||
 	    of_device_is_compatible(np, "snps,dwmac-4.10a") ||
 	    of_device_is_compatible(np, "snps,dwmac-4.20a") ||