stmmac: Add support for SIMATIC IOT2000 platform

The IOT2000 is industrial controller platform, derived from the Intel
Galileo Gen2 board. The variant IOT2020 comes with one LAN port, the
IOT2040 has two of them. They can be told apart based on the board asset
tag in the DMI table.

Based on patch by Sascha Weisenberger.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Sascha Weisenberger <sascha.weisenberger@siemens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -32,6 +32,7 @@
  */
 struct stmmac_pci_dmi_data {
 	const char *name;
+	const char *asset_tag;
 	unsigned int func;
 	int phy_addr;
 };
@@ -46,6 +47,7 @@ struct stmmac_pci_info {
 static int stmmac_pci_find_phy_addr(struct stmmac_pci_info *info)
 {
 	const char *name = dmi_get_system_info(DMI_BOARD_NAME);
+	const char *asset_tag = dmi_get_system_info(DMI_BOARD_ASSET_TAG);
 	unsigned int func = PCI_FUNC(info->pdev->devfn);
 	struct stmmac_pci_dmi_data *dmi;
 
@@ -57,9 +59,13 @@ static int stmmac_pci_find_phy_addr(struct stmmac_pci_info *info)
 		return 1;
 
 	for (dmi = info->dmi; dmi->name && *dmi->name; dmi++) {
-		if (!strcmp(dmi->name, name) && dmi->func == func)
+		if (!strcmp(dmi->name, name) && dmi->func == func) {
+			/* If asset tag is provided, match on it as well. */
+			if (dmi->asset_tag && strcmp(dmi->asset_tag, asset_tag))
+				continue;
 			return dmi->phy_addr;
 		}
+	}
 
 	return -ENODEV;
 }
@@ -153,6 +159,24 @@ static struct stmmac_pci_dmi_data quark_pci_dmi_data[] = {
 		.func = 6,
 		.phy_addr = 1,
 	},
+	{
+		.name = "SIMATIC IOT2000",
+		.asset_tag = "6ES7647-0AA00-0YA2",
+		.func = 6,
+		.phy_addr = 1,
+	},
+	{
+		.name = "SIMATIC IOT2000",
+		.asset_tag = "6ES7647-0AA00-1YA2",
+		.func = 6,
+		.phy_addr = 1,
+	},
+	{
+		.name = "SIMATIC IOT2000",
+		.asset_tag = "6ES7647-0AA00-1YA2",
+		.func = 7,
+		.phy_addr = 1,
+	},
 	{}
 };