omap3/sys_info: provide interface to read die id

introduce get_die_id() function which allows generation of
information such as fake MAC address from the processor ID code.

Signed-off-by: Nishanth Menon <nm@ti.com>

arch/arm/cpu/armv7/omap3/sys_info.c

@@ -41,11 +41,23 @@ static char *rev_s_37xx[CPU_37XX_MAX_REV] = {
 #endif /* CONFIG_DISPLAY_CPUINFO */
 
 /*****************************************************************
+ * get_dieid(u32 *id) - read die ID
+ *****************************************************************/
+void get_dieid(u32 *id)
+{
+	struct ctrl_id *id_base = (struct ctrl_id *)OMAP34XX_ID_L4_IO_BASE;
+
+	id[3] = readl(&id_base->die_id_0);
+	id[2] = readl(&id_base->die_id_1);
+	id[1] = readl(&id_base->die_id_2);
+	id[0] = readl(&id_base->die_id_3);
+}
+
+/*****************************************************************
  * dieid_num_r(void) - read and set die ID
  *****************************************************************/
 void dieid_num_r(void)
 {
-	struct ctrl_id *id_base = (struct ctrl_id *)OMAP34XX_ID_L4_IO_BASE;
 	char *uid_s, die_id[34];
 	u32 id[4];
 
@@ -54,10 +66,7 @@ void dieid_num_r(void)
 	uid_s = getenv("dieid#");
 
 	if (uid_s == NULL) {
-		id[3] = readl(&id_base->die_id_0);
-		id[2] = readl(&id_base->die_id_1);
-		id[1] = readl(&id_base->die_id_2);
-		id[0] = readl(&id_base->die_id_3);
+		get_dieid(id);
 		sprintf(die_id, "%08x%08x%08x%08x", id[0], id[1], id[2], id[3]);
 		setenv("dieid#", die_id);
 		uid_s = die_id;

arch/arm/include/asm/arch-omap3/sys_proto.h

@@ -68,6 +68,7 @@ void make_cs1_contiguous(void);
 void omap_nand_switch_ecc(uint32_t, uint32_t);
 void power_init_r(void);
 void dieid_num_r(void);
+void get_dieid(u32 *id);
 void do_omap3_emu_romcode_call(u32 service_id, u32 parameters);
 void omap3_gp_romcode_call(u32 service_id, u32 parameter);
 u32 warm_reset(void);