omap3: Definitions for SYS_BOOT-based fallback boot device selection

This introduces code to read the value of the SYS_BOOT pins on the OMAP3, as
well as the memory-preferred scheme for the interpretation of each value.

Signed-off-by: Paul Kocialkowski <contact@paulk.fr>

arch/arm/cpu/armv7/omap3/Makefile

@@ -8,6 +8,7 @@
 obj-y	:= lowlevel_init.o
 
 obj-y	+= board.o
+obj-y	+= boot.o
 obj-y	+= clock.o
 obj-y	+= sys_info.o
 ifdef CONFIG_SPL_BUILD

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

@@ -0,0 +1,58 @@
+/*
+ * OMAP3 boot
+ *
+ * Copyright (C) 2015 Paul Kocialkowski <contact@paulk.fr>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/sys_proto.h>
+#include <spl.h>
+
+static u32 boot_devices[] = {
+	BOOT_DEVICE_ONENAND,
+	BOOT_DEVICE_NAND,
+	BOOT_DEVICE_ONENAND,
+	BOOT_DEVICE_MMC2,
+	BOOT_DEVICE_ONENAND,
+	BOOT_DEVICE_MMC2,
+	BOOT_DEVICE_MMC1,
+	BOOT_DEVICE_XIP,
+	BOOT_DEVICE_XIPWAIT,
+	BOOT_DEVICE_MMC2,
+	BOOT_DEVICE_XIP,
+	BOOT_DEVICE_XIPWAIT,
+	BOOT_DEVICE_NAND,
+	BOOT_DEVICE_XIP,
+	BOOT_DEVICE_XIPWAIT,
+	BOOT_DEVICE_NAND,
+	BOOT_DEVICE_ONENAND,
+	BOOT_DEVICE_MMC2,
+	BOOT_DEVICE_MMC1,
+	BOOT_DEVICE_XIP,
+	BOOT_DEVICE_XIPWAIT,
+	BOOT_DEVICE_NAND,
+	BOOT_DEVICE_ONENAND,
+	BOOT_DEVICE_MMC2,
+	BOOT_DEVICE_MMC1,
+	BOOT_DEVICE_XIP,
+	BOOT_DEVICE_XIPWAIT,
+	BOOT_DEVICE_NAND,
+	BOOT_DEVICE_MMC2_2,
+};
+
+u32 omap_sys_boot_device(void)
+{
+	struct ctrl *ctrl_base = (struct ctrl *)OMAP34XX_CTRL_BASE;
+	u32 sys_boot;
+
+	/* Grab the first 5 bits of the status register for SYS_BOOT. */
+	sys_boot = readl(&ctrl_base->status) & ((1 << 5) - 1);
+
+	if (sys_boot >= (sizeof(boot_devices) / sizeof(u32)))
+		return BOOT_DEVICE_NONE;
+
+	return boot_devices[sys_boot];
+}

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

@@ -52,7 +52,6 @@ void set_muxconf_regs(void);
 u32 get_cpu_family(void);
 u32 get_cpu_rev(void);
 u32 get_sku_id(void);
-u32 get_sysboot_value(void);
 u32 is_gpmc_muxed(void);
 u32 get_gpmc0_type(void);
 u32 get_gpmc0_width(void);