stmmac: add new DT platform entries for GMAC4

This is to support the snps,dwmac-4.00 and snps,dwmac-4.10a
and related features on the platform driver.
See binding doc for further details.

Signed-off-by: Giuseppe Cavallaro <[e-mail]>
Signed-off-by: Alexandre TORGUE <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

Documentation/devicetree/bindings/net/stmmac.txt

···
 	- snps,fb: fixed-burst
 	- snps,mb: mixed-burst
 	- snps,rb: rebuild INCRx Burst
+	- snps,tso: this enables the TSO feature otherwise it will be managed by
+	    MAC HW capability register.
 - mdio: with compatible = "snps,dwmac-mdio", create and register mdio bus.
 
 Examples:

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

···
 		plat->pmt = 1;
 	}
 
+	if (of_device_is_compatible(np, "snps,dwmac-4.00") ||
+	    of_device_is_compatible(np, "snps,dwmac-4.10a")) {
+		plat->has_gmac4 = 1;
+		plat->pmt = 1;
+		plat->tso_en = of_property_read_bool(np, "snps,tso");
+	}
+
 	if (of_device_is_compatible(np, "snps,dwmac-3.610") ||
 		of_device_is_compatible(np, "snps,dwmac-3.710")) {
 		plat->enh_desc = 1;

include/linux/stmmac.h

···
 	void (*exit)(struct platform_device *pdev, void *priv);
 	void *bsp_priv;
 	struct stmmac_axi *axi;
+	int has_gmac4;
+	bool tso_en;
 };
 #endif