3 files changed, 116 insertions, 1 deletions
diff --git a/board/freescale/mx6sabresd/README b/board/freescale/mx6sabresd/README
new file mode 100644
index 0000000000..5814b9d380
--- /dev/null
+++ b/board/freescale/mx6sabresd/README
@@ -0,0 +1,103 @@
+How to use and build U-Boot on mx6sabresd:
+----------------------------------
+
+Currently there are three methods for booting mx6sabresd boards:
+
+1. Booting via Normal U-Boot (u-boot.imx)
+
+2. Booting via SPL (SPL and u-boot.img)
+
+3. Booting via Falcon mode (SPL launches the kernel directly)
+
+
+1. Booting via Normal U-Boot
+----------------------------
+
+$ make mx6qsabresd_defconfig (If you want to build for mx6qsabresd)
+
+or
+
+$ make mx6dlsabresd_defconfig (If you want to build for mx6dlsabresd)
+
+$ make
+
+This will generate the image called u-boot.imx.
+
+- Flash the u-boot.imx binary into the SD card:
+
+$ sudo dd if=u-boot.imx of=/dev/sdb bs=1K seek=1 && sync
+
+
+2. Booting via SPL
+------------------
+
+Other method for building U-Boot on mx6qsabresd and mx6qpsabresd is
+through SPL. In order to do so:
+
+$ make mx6sabresd_spl_defconfig
+$ make
+
+This will generate the SPL image called SPL and the u-boot.img.
+
+- Flash the SPL image into the SD card:
+
+$ sudo dd if=SPL of=/dev/sdb bs=1K seek=1 && sync
+
+- Flash the u-boot.img image into the SD card:
+
+$ sudo dd if=u-boot.img of=/dev/sdbbs=1K seek=69 && sync
+
+
+3. Booting via Falcon mode
+--------------------------
+
+$ make mx6sabresd_spl_defconfig
+$ make
+
+This will generate the SPL image called SPL and the u-boot.img.
+
+- Flash the SPL image into the SD card:
+
+$ sudo dd if=SPL of=/dev/sdb bs=1K seek=1 oflag=sync status=none && sync
+
+- Flash the u-boot.img image into the SD card:
+
+$ sudo dd if=u-boot.img of=/dev/sdbbs=1K seek=69 oflag=sync status=none && sync
+
+Create a partition for root file system and extract it there:
+
+$ sudo tar xvf rootfs.tar.gz -C /media/root
+
+The SD card must have enough space for raw "args" and "kernel".
+To configure Falcon mode for the first time, on U-Boot do the following commands:
+
+- Setup the IP server:
+
+# setenv serverip <server_ip_address>
+
+- Download dtb file:
+
+# dhcp ${fdt_addr} imx6q-sabresd.dtb
+
+- Download kernel image:
+
+# dhcp ${loadaddr} uImage
+
+- Write kernel at 2MB offset:
+
+# mmc write ${loadaddr} 0x1000 0x4000
+
+- Setup kernel bootargs:
+
+# setenv bootargs "console=ttymxc0,115200 root=/dev/mmcblk1p1 rootfstype=ext4 rootwait quiet rw"
+
+- Prepare args:
+
+# spl export fdt ${loadaddr} - ${fdt_addr}
+
+- Write args 1MB data (0x800 sectors) to 1MB offset (0x800 sectors)
+
+# mmc write 18000000 0x800 0x800
+
+- Press KEY_VOL_UP key, power up the board and then SPL binary will
+launch the kernel directly.
diff --git a/board/freescale/mx6sabresd/mx6dlsabresd.cfg b/board/freescale/mx6sabresd/mx6dlsabresd.cfg
index f35f22ea82..be9f87f666 100644
--- a/board/freescale/mx6sabresd/mx6dlsabresd.cfg
+++ b/board/freescale/mx6sabresd/mx6dlsabresd.cfg
@@ -3,7 +3,7 @@
  *
  * SPDX-License-Identifier:	GPL-2.0+
  *
- * Refer docs/README.imxmage for more details about how-to configure
+ * Refer doc/README.imximage for more details about how-to configure
  * and create imximage boot image
  *
  * The syntax is taken as close as possible with the kwbimage
diff --git a/board/freescale/mx6sabresd/mx6sabresd.c b/board/freescale/mx6sabresd/mx6sabresd.c
index e58c03cca7..2b6d7be0a3 100644
--- a/board/freescale/mx6sabresd/mx6sabresd.c
+++ b/board/freescale/mx6sabresd/mx6sabresd.c
@@ -57,6 +57,8 @@ DECLARE_GLOBAL_DATA_PTR;
 
 #define DISP0_PWR_EN	IMX_GPIO_NR(1, 21)
 
+#define KEY_VOL_UP	IMX_GPIO_NR(1, 4)
+
 int dram_init(void)
 {
 	gd->ram_size = imx_ddr_size();
@@ -682,6 +684,16 @@ int checkboard(void)
 #include <spl.h>
 #include <libfdt.h>
 
+#ifdef CONFIG_SPL_OS_BOOT
+int spl_start_uboot(void)
+{
+	gpio_direction_input(KEY_VOL_UP);
+
+	/* Only enter in Falcon mode if KEY_VOL_UP is pressed */
+	return gpio_get_value(KEY_VOL_UP);
+}
+#endif
+
 static void ccgr_init(void)
 {
 	struct mxc_ccm_reg *ccm = (struct mxc_ccm_reg *)CCM_BASE_ADDR;