rockchip: add boot-mode support for rk3288, rk3036

rockchip platform have a protocol to pass the the kernel reboot mode to bootloader
by some special registers when system reboot. In bootloader we should read it and take action.

We can only setup boot_mode in board_late_init becasue "setenv" need env setuped.
So add CONFIG_BOARD_LATE_INIT to common header and use a entry "rk_board_late_init"
to replace "board_late_init" in board file.

Signed-off-by: Jacob Chen <jacob2.chen@rock-chips.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-rockchip/rk3288-board.c b/arch/arm/mach-rockchip/rk3288-board.c
index 6c36bf9..baf9522 100644
--- a/arch/arm/mach-rockchip/rk3288-board.c
+++ b/arch/arm/mach-rockchip/rk3288-board.c
@@ -8,25 +8,65 @@
 #include <clk.h>
 #include <dm.h>
 #include <ram.h>
+#include <syscon.h>
 #include <asm/io.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/periph.h>
+#include <asm/arch/pmu_rk3288.h>
+#include <asm/arch/boot_mode.h>
 #include <asm/gpio.h>
 #include <dm/pinctrl.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
+#define PMU_BASE	0xff730000
+
+static void setup_boot_mode(void)
+{
+	struct rk3288_pmu *const pmu = (void *)PMU_BASE;
+	int boot_mode = readl(&pmu->sys_reg[0]);
+
+	debug("boot mode %x.\n", boot_mode);
+
+	/* Clear boot mode */
+	writel(BOOT_NORMAL, &pmu->sys_reg[0]);
+
+	switch (boot_mode) {
+	case BOOT_FASTBOOT:
+		printf("enter fastboot!\n");
+		setenv("preboot", "setenv preboot; fastboot usb0");
+		break;
+	case BOOT_UMS:
+		printf("enter UMS!\n");
+		setenv("preboot", "setenv preboot; if mmc dev 0;"
+		       "then ums mmc 0; else ums mmc 1;fi");
+		break;
+	}
+}
+
+__weak int rk_board_late_init(void)
+{
+	return 0;
+}
+
+int board_late_init(void)
+{
+	setup_boot_mode();
+
+	return rk_board_late_init();
+}
+
 int board_init(void)
 {
 #ifdef CONFIG_ROCKCHIP_SPL_BACK_TO_BROM
 	struct udevice *pinctrl;
 	int ret;
 
-    /*
-     * We need to implement sdcard iomux here for the further
-     * initlization, otherwise, it'll hit sdcard command sending
-     * timeout exception.
-     */
+	/*
+	 * We need to implement sdcard iomux here for the further
+	 * initlization, otherwise, it'll hit sdcard command sending
+	 * timeout exception.
+	 */
 	ret = uclass_get_device(UCLASS_PINCTRL, 0, &pinctrl);
 	if (ret) {
 		debug("%s: Cannot find pinctrl device\n", __func__);