warp: Use PARTUUID to specify the rootfs location

warp can run different kernel versions, such as NXP 4.1 or
mainline.

Currently the rootfs location is passed via mmcblk number and the
problem with this approach is that the mmcblk number for the eMMC
changes depending on the kernel version.

In order to avoid such issue, use UUID method to specify the rootfs
location.

Succesfully tested booting a NXP 4.1 and also a mainline 4.12 kernel.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Otavio Salvador <otavio@ossystems.com.br>

diff --git a/configs/warp_defconfig b/configs/warp_defconfig
index e29afe7b4a112a298bd6ebe09ccd90db192ee4f2..36b3b160653d5d92ab6ab70f45f945ece183c31a 100644 (file)
--- a/configs/warp_defconfig
+++ b/configs/warp_defconfig
@@ -10,6 +10,7 @@ CONFIG_CMD_BOOTZ=y
 # CONFIG_CMD_IMLS is not set
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_MMC=y
+CONFIG_CMD_PART=y
 CONFIG_CMD_I2C=y
 CONFIG_CMD_USB=y
 CONFIG_CMD_DFU=y

diff --git a/include/configs/warp.h b/include/configs/warp.h
index e3f79b199a3a82bfb0a4b3821abba19bdb90edf0..389831595b05b98703aa5d222dd81f4a2158911d 100644 (file)
--- a/include/configs/warp.h
+++ b/include/configs/warp.h
@@ -95,10 +95,10 @@
        "ip_dyn=yes\0" \
        "mmcdev=0\0" \
        "mmcpart=1\0" \
-       "mmcroot=/dev/mmcblk0p2 rootwait rw\0" \
+       "finduuid=part uuid mmc 0:2 uuid\0" \
        "dfu_alt_info=boot raw 0x2 0x400 mmcpart 1\0" \
        "mmcargs=setenv bootargs console=${console},${baudrate} " \
-               "root=${mmcroot}\0" \
+               "root=PARTUUID=${uuid} rootwait rw\0" \
        "loadbootscript=" \
                "fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} ${script};\0" \
        "bootscript=echo Running bootscript from mmc ...; " \
@@ -106,6 +106,7 @@
        "loadimage=fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} ${image}\0" \
        "loadfdt=fatload mmc ${mmcdev}:${mmcpart} ${fdt_addr} ${fdt_file}\0" \
        "mmcboot=echo Booting from mmc ...; " \
+               "run finduuid; " \
                "run mmcargs; " \
                "if test ${boot_fdt} = yes || test ${boot_fdt} = try; then " \
                        "if run loadfdt; then " \