rockchip: kylin: Check fastboot request

We will save boot mode flag in grf's os_reg[4], if fastboot
requested or fastboot key pressed, try to enter fastboot mode
at preboot stage.

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/board/kylin/kylin_rk3036/kylin_rk3036.c b/board/kylin/kylin_rk3036/kylin_rk3036.c
index 40d6b52..2a25871 100644
--- a/board/kylin/kylin_rk3036/kylin_rk3036.c
+++ b/board/kylin/kylin_rk3036/kylin_rk3036.c
@@ -8,10 +8,14 @@
 #include <dm.h>
 #include <asm/io.h>
 #include <asm/arch/uart.h>
+#include <asm/arch-rockchip/grf_rk3036.h>
 #include <asm/arch/sdram_rk3036.h>
+#include <asm/gpio.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
+#define GRF_BASE	0x20008000
+
 void get_ddr_config(struct rk3036_ddr_config *config)
 {
 	/* K4B4G1646Q config */
@@ -28,6 +32,34 @@
 	config->bw = 1;
 }
 
+#define FASTBOOT_KEY_GPIO 93
+
+int fastboot_key_pressed(void)
+{
+	gpio_request(FASTBOOT_KEY_GPIO, "fastboot_key");
+	gpio_direction_input(FASTBOOT_KEY_GPIO);
+	return !gpio_get_value(FASTBOOT_KEY_GPIO);
+}
+
+#define ROCKCHIP_BOOT_MODE_FASTBOOT	0x5242C309
+
+int board_late_init(void)
+{
+	struct rk3036_grf * const grf = (void *)GRF_BASE;
+	int boot_mode = readl(&grf->os_reg[4]);
+
+	/* Clear boot mode */
+	writel(0, &grf->os_reg[4]);
+
+	if (boot_mode == ROCKCHIP_BOOT_MODE_FASTBOOT ||
+	    fastboot_key_pressed()) {
+		printf("enter fastboot!\n");
+		setenv("preboot", "setenv preboot; fastboot usb0");
+	}
+
+	return 0;
+}
+
 int board_init(void)
 {
 	return 0;
diff --git a/include/configs/kylin_rk3036.h b/include/configs/kylin_rk3036.h
index b750b26..d8fd706 100644
--- a/include/configs/kylin_rk3036.h
+++ b/include/configs/kylin_rk3036.h
@@ -38,4 +38,7 @@
 
 #endif
 
+#define CONFIG_BOARD_LATE_INIT
+#define CONFIG_PREBOOT
+
 #endif