ARM: meson-gx: Reset GXL/GXM to external PHY when not using internal PHY

When using External PHY, reset the mux to use the external PHY in case U-Boot
was chainloaded from a misconfigured bootloader.

Fixes: 33e3378091 ("ARM: meson: rework soc arch file to prepare for new SoC")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/arch/arm/mach-meson/board-gx.c b/arch/arm/mach-meson/board-gx.c
index 5b0126a..ab8f1a8 100644
--- a/arch/arm/mach-meson/board-gx.c
+++ b/arch/arm/mach-meson/board-gx.c
@@ -117,6 +117,11 @@
 			     GX_ETH_REG_0_TX_RATIO(4) |
 			     GX_ETH_REG_0_PHY_CLK_EN |
 			     GX_ETH_REG_0_CLK_EN);
+
+		/* Reset to external PHY */
+		if(!IS_ENABLED(CONFIG_MESON_GXBB))
+			writel(0x2009087f, GX_ETH_REG_3);
+
 		break;
 
 	case PHY_INTERFACE_MODE_RMII:
@@ -124,11 +129,13 @@
 		out_le32(GX_ETH_REG_0, GX_ETH_REG_0_INVERT_RMII_CLK |
 					 GX_ETH_REG_0_CLK_EN);
 
-		/* Use GXL RMII Internal PHY */
-		if (IS_ENABLED(CONFIG_MESON_GXL) &&
-		    (flags & MESON_USE_INTERNAL_RMII_PHY)) {
-			writel(0x10110181, GX_ETH_REG_2);
-			writel(0xe40908ff, GX_ETH_REG_3);
+		/* Use GXL RMII Internal PHY (also on GXM) */
+		if (!IS_ENABLED(CONFIG_MESON_GXBB)) {
+			if ((flags & MESON_USE_INTERNAL_RMII_PHY)) {
+				writel(0x10110181, GX_ETH_REG_2);
+				writel(0xe40908ff, GX_ETH_REG_3);
+			} else
+				writel(0x2009087f, GX_ETH_REG_3);
 		}
 
 		break;