OMAP: common: consolidate fake USB ethernet MAC address creation

TI platforms such as OMAP5uevm, PandaBoard, use equivalent
logic to generate fake USB MAC address from device unique DIE ID.

Consolidate this to a generic location such that other TI platforms such
as BeagleBoard-XM can also use the same.

NOTE: at this point in time, I dont yet see a need for a generic dummy
ethernet MAC address creation function, but if there is a need in the
future, this can be further abstracted out.

Signed-off-by: Nishanth Menon <nm@ti.com>
diff --git a/arch/arm/cpu/armv7/omap-common/utils.c b/arch/arm/cpu/armv7/omap-common/utils.c
index aabf2bd..1696c2d 100644
--- a/arch/arm/cpu/armv7/omap-common/utils.c
+++ b/arch/arm/cpu/armv7/omap-common/utils.c
@@ -5,6 +5,7 @@
  * SPDX-License-Identifier:	GPL-2.0+
  */
 #include <common.h>
+#include <asm/arch/sys_proto.h>
 static void do_cancel_out(u32 *num, u32 *den, u32 factor)
 {
 	while (1) {
@@ -39,3 +40,23 @@
 		*den = (*den + 1) / 2;
 	}
 }
+
+void __weak usb_fake_mac_from_die_id(u32 *id)
+{
+	uint8_t device_mac[6];
+
+	if (!getenv("usbethaddr")) {
+		/*
+		 * create a fake MAC address from the processor ID code.
+		 * first byte is 0x02 to signify locally administered.
+		 */
+		device_mac[0] = 0x02;
+		device_mac[1] = id[3] & 0xff;
+		device_mac[2] = id[2] & 0xff;
+		device_mac[3] = id[1] & 0xff;
+		device_mac[4] = id[0] & 0xff;
+		device_mac[5] = (id[0] >> 8) & 0xff;
+
+		eth_setenv_enetaddr("usbethaddr", device_mac);
+	}
+}
diff --git a/arch/arm/include/asm/omap_common.h b/arch/arm/include/asm/omap_common.h
index 04925bc..729723a 100644
--- a/arch/arm/include/asm/omap_common.h
+++ b/arch/arm/include/asm/omap_common.h
@@ -574,6 +574,8 @@
 	       u32 txdone, u32 txdone_mask, u32 opp);
 s8 abb_setup_ldovbb(u32 fuse, u32 ldovbb);
 
+void usb_fake_mac_from_die_id(u32 *id);
+
 /* HW Init Context */
 #define OMAP_INIT_CONTEXT_SPL			0
 #define OMAP_INIT_CONTEXT_UBOOT_FROM_NOR	1
diff --git a/board/ti/omap5_uevm/evm.c b/board/ti/omap5_uevm/evm.c
index 3eaa5ac..4666b38 100644
--- a/board/ti/omap5_uevm/evm.c
+++ b/board/ti/omap5_uevm/evm.c
@@ -119,28 +119,19 @@
 int misc_init_r(void)
 {
 	int reg;
-	uint8_t device_mac[6];
+	u32 id[4];
 
 #ifdef CONFIG_PALMAS_POWER
 	palmas_init_settings();
 #endif
 
-	if (!getenv("usbethaddr")) {
-		reg = DIE_ID_REG_BASE + DIE_ID_REG_OFFSET;
+	reg = DIE_ID_REG_BASE + DIE_ID_REG_OFFSET;
 
-		/*
-		 * create a fake MAC address from the processor ID code.
-		 * first byte is 0x02 to signify locally administered.
-		 */
-		device_mac[0] = 0x02;
-		device_mac[1] = readl(reg + 0x10) & 0xff;
-		device_mac[2] = readl(reg + 0xC) & 0xff;
-		device_mac[3] = readl(reg + 0x8) & 0xff;
-		device_mac[4] = readl(reg) & 0xff;
-		device_mac[5] = (readl(reg) >> 8) & 0xff;
-
-		eth_setenv_enetaddr("usbethaddr", device_mac);
-	}
+	id[0] = readl(reg);
+	id[1] = readl(reg + 0x8);
+	id[2] = readl(reg + 0xC);
+	id[3] = readl(reg + 0x10);
+	usb_fake_mac_from_die_id(id);
 
 	return 0;
 }
diff --git a/board/ti/panda/panda.c b/board/ti/panda/panda.c
index 0dfb4ad..16368cb 100644
--- a/board/ti/panda/panda.c
+++ b/board/ti/panda/panda.c
@@ -193,7 +193,7 @@
 {
 	int phy_type;
 	u32 auxclk, altclksrc;
-	uint8_t device_mac[6];
+	u32 id[4];
 
 	/* EHCI is not supported on ES1.0 */
 	if (omap_revision() == OMAP4430_ES1_0)
@@ -247,20 +247,11 @@
 
 	writel(altclksrc, &scrm->altclksrc);
 
-	if (!getenv("usbethaddr")) {
-		/*
-		 * create a fake MAC address from the processor ID code.
-		 * first byte is 0x02 to signify locally administered.
-		 */
-		device_mac[0] = 0x02;
-		device_mac[1] = readl(STD_FUSE_DIE_ID_3) & 0xff;
-		device_mac[2] = readl(STD_FUSE_DIE_ID_2) & 0xff;
-		device_mac[3] = readl(STD_FUSE_DIE_ID_1) & 0xff;
-		device_mac[4] = readl(STD_FUSE_DIE_ID_0) & 0xff;
-		device_mac[5] = (readl(STD_FUSE_DIE_ID_0) >> 8) & 0xff;
-
-		eth_setenv_enetaddr("usbethaddr", device_mac);
-	}
+	id[0] = readl(STD_FUSE_DIE_ID_0);
+	id[1] = readl(STD_FUSE_DIE_ID_1);
+	id[2] = readl(STD_FUSE_DIE_ID_2);
+	id[3] = readl(STD_FUSE_DIE_ID_3);
+	usb_fake_mac_from_die_id(id);
 
 	return 0;
 }