arm: omap4: panda: Add reading of the board revision

Detect if we are running on a panda revision A1-A6,
or an ES panda board. This can be done by reading
the level of GPIOs and checking the processor revisions.
This should result in:
Panda 4430:
     GPIO171, GPIO101, GPIO182: 0 1 1 => A1-A5
     GPIO171, GPIO101, GPIO182: 1 0 1 => A6
Panda ES:
     GPIO2, GPIO3, GPIO171, GPIO48, GPIO182: 0 0 0 1 1 => B1/B2
     GPIO2, GPIO3, GPIO171, GPIO48, GPIO182: 0 0 1 1 1 => B3

Set the board name appropriately for the board revision that
is detected.

Update the findfdt macro to load the a4 device tree binary.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
[trini: %s/CONTROL_PADCONF_CORE/(*ctrl)->control_padconf_core_base/ and
 formatting for that]
Signed-off-by: Tom Rini <trini@ti.com>
diff --git a/board/ti/panda/panda.c b/board/ti/panda/panda.c
index 90ae29e..84c863d 100644
--- a/board/ti/panda/panda.c
+++ b/board/ti/panda/panda.c
@@ -37,6 +37,11 @@
 #endif
 
 #define PANDA_ULPI_PHY_TYPE_GPIO       182
+#define PANDA_BOARD_ID_1_GPIO          101
+#define PANDA_ES_BOARD_ID_1_GPIO        48
+#define PANDA_BOARD_ID_2_GPIO          171
+#define PANDA_ES_BOARD_ID_3_GPIO         3
+#define PANDA_ES_BOARD_ID_4_GPIO         2
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -66,6 +71,73 @@
 	return 0;
 }
 
+/*
+* Routine: get_board_revision
+* Description: Detect if we are running on a panda revision A1-A6,
+*              or an ES panda board. This can be done by reading
+*              the level of GPIOs and checking the processor revisions.
+*              This should result in:
+*			Panda 4430:
+*              GPIO171, GPIO101, GPIO182: 0 1 1 => A1-A5
+*              GPIO171, GPIO101, GPIO182: 1 0 1 => A6
+*			Panda ES:
+*              GPIO2, GPIO3, GPIO171, GPIO48, GPIO182: 0 0 0 1 1 => B1/B2
+*              GPIO2, GPIO3, GPIO171, GPIO48, GPIO182: 0 0 1 1 1 => B3
+*/
+int get_board_revision(void)
+{
+	int board_id0, board_id1, board_id2;
+	int board_id3, board_id4;
+	int board_id;
+
+	int processor_rev = omap_revision();
+
+	/* Setup the mux for the common board ID pins (gpio 171 and 182) */
+	writew((IEN | M3), (*ctrl)->control_padconf_core_base + UNIPRO_TX0);
+	writew((IEN | M3), (*ctrl)->control_padconf_core_base + FREF_CLK2_OUT);
+
+	board_id0 = gpio_get_value(PANDA_ULPI_PHY_TYPE_GPIO);
+	board_id2 = gpio_get_value(PANDA_BOARD_ID_2_GPIO);
+
+	if ((processor_rev >= OMAP4460_ES1_0 &&
+	     processor_rev <= OMAP4460_ES1_1)) {
+		/*
+		 * Setup the mux for the ES specific board ID pins (gpio 101,
+		 * 2 and 3.
+		 */
+		writew((IEN | M3), (*ctrl)->control_padconf_core_base +
+				GPMC_A24);
+		writew((IEN | M3), (*ctrl)->control_padconf_core_base +
+				UNIPRO_RY0);
+		writew((IEN | M3), (*ctrl)->control_padconf_core_base +
+				UNIPRO_RX1);
+
+		board_id1 = gpio_get_value(PANDA_ES_BOARD_ID_1_GPIO);
+		board_id3 = gpio_get_value(PANDA_ES_BOARD_ID_3_GPIO);
+		board_id4 = gpio_get_value(PANDA_ES_BOARD_ID_4_GPIO);
+
+#ifdef CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
+		setenv("board_name", strcat(CONFIG_SYS_BOARD, "-es"));
+#endif
+		board_id = ((board_id4 << 4) | (board_id3 << 3) |
+			(board_id2 << 2) | (board_id1 << 1) | (board_id0));
+	} else {
+		/* Setup the mux for the Ax specific board ID pins (gpio 101) */
+		writew((IEN | M3), (*ctrl)->control_padconf_core_base +
+				FREF_CLK2_OUT);
+
+		board_id1 = gpio_get_value(PANDA_BOARD_ID_1_GPIO);
+		board_id = ((board_id2 << 2) | (board_id1 << 1) | (board_id0));
+
+#ifdef CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
+		if ((board_id >= 0x3) && (processor_rev == OMAP4430_ES2_3))
+			setenv("board_name", strcat(CONFIG_SYS_BOARD, "-a4"));
+#endif
+	}
+
+	return board_id;
+}
+
 /**
  * @brief misc_init_r - Configure Panda board specific configurations
  * such as power configurations, ethernet initialization as phase2 of
@@ -82,11 +154,7 @@
 	if (omap_revision() == OMAP4430_ES1_0)
 		return 0;
 
-#ifdef CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
-	if (omap_revision() >= OMAP4460_ES1_0 ||
-		omap_revision() <= OMAP4460_ES1_1)
-		setenv("board_name", strcat(CONFIG_SYS_BOARD, "-es"));
-#endif
+	get_board_revision();
 
 	gpio_direction_input(PANDA_ULPI_PHY_TYPE_GPIO);
 	phy_type = gpio_get_value(PANDA_ULPI_PHY_TYPE_GPIO);
diff --git a/include/configs/omap4_common.h b/include/configs/omap4_common.h
index f47d52e..2fa4382 100644
--- a/include/configs/omap4_common.h
+++ b/include/configs/omap4_common.h
@@ -178,6 +178,8 @@
 			"setenv fdtfile omap4-sdp.dtb; fi; " \
 		"if test $board_name = panda; then " \
 			"setenv fdtfile omap4-panda.dtb; fi;" \
+		"if test $board_name = panda-a4; then " \
+			"setenv fdtfile omap4-panda-a4.dtb; fi;" \
 		"if test $board_name = panda-es; then " \
 			"setenv fdtfile omap4-panda-es.dtb; fi;" \
 		"if test $fdtfile = undefined; then " \