From: Fabio Estevam festevam@gmail.com
Falcon mode allows the SPL to load and jump directly to the kernel, without loading U-Boot proper.
Add detailed step by step on how to use Falcon mode on pico-imx6ul.
Signed-off-by: Fabio Estevam festevam@gmail.com Signed-off-by: Otavio Salvador otavio@ossystems.com.br ---
Changes in v3: - new patch
Changes in v2: None
board/technexion/pico-imx6ul/README | 92 +++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+)
diff --git a/board/technexion/pico-imx6ul/README b/board/technexion/pico-imx6ul/README index 66dc977d49..1cabd90759 100644 --- a/board/technexion/pico-imx6ul/README +++ b/board/technexion/pico-imx6ul/README @@ -65,3 +65,95 @@ Remove power from the pico board. Put pico board into normal boot mode.
Power up the board and the new updated U-Boot should boot from eMMC. + +Booting in Falcon mode +====================== + +Generate a uImage kernel: + +$ make imx_v6_v7_defconfig (Using the default imx_v6_v7_defconfig configuration +just for an example. In order to boot faster the user should customize the +defconfig by only enabling the minimal required drivers). + +$ make -j4 uImage LOADADDR=0x80800000 + +$ cp arch/arm/boot/uImage /tftpboot +$ cp arch/arm/boot/dts/imx6ul-pico-hobbit.dtb /tftpboot + +In the U-Boot prompt: + +Setup the server and board IP addresses: +=> setenv serverip 192.168.0.10 +=> setenv ipaddr 192.168.0.11 + +Get the dtb file: +=> tftp ${fdt_addr} imx6ul-pico-hobbit.dtb + +Get the kernel: +=> tftp ${loadaddr} uImage + +Write the kernel at 2MB offset: +=> mmc write ${loadaddr} 0x1000 0x4000 + +Setup the bootargs: +=> setenv bootargs 'console=ttymxc5,115200 root=/dev/mmcblk0p2 rootfstype=ext4 rootwait rw' + +Prepare args: +=> spl export fdt ${loadaddr} - ${fdt_addr} +## Booting kernel from Legacy Image at 82000000 ... + Image Name: Linux-4.19.0-rc2-next-20180905-0 + Image Type: ARM Linux Kernel Image (uncompressed) + Data Size: 8365608 Bytes = 8 MiB + Load Address: 80800000 + Entry Point: 80800000 + Verifying Checksum ... OK +## Flattened Device Tree blob at 83000000 + Booting using the fdt blob at 0x83000000 + Loading Kernel Image ... OK + Using Device Tree in place at 83000000, end 83009c63 +subcommand not supported +subcommand not supported + Using Device Tree in place at 83000000, end 8300cc63 +Argument image is now in RAM: 0x83000000 + +Write 1MB of args data (0x800 sectors) to 1MB offset (0x800 sectors): + +=> mmc write ${fdt_addr} 0x800 0x800 + +In order to boot with Falcon mode, activate the CONFIG_SPL_OS_BOOT +option in the defconfig + +--- a/configs/pico-hobbit-imx6ul_defconfig ++++ b/configs/pico-hobbit-imx6ul_defconfig +@@ -53,3 +53,4 @@ CONFIG_USB_GADGET_VENDOR_NUM=0x0525 + CONFIG_USB_GADGET_PRODUCT_NUM=0xa4a5 + CONFIG_CI_UDC=y + CONFIG_OF_LIBFDT=y ++CONFIG_SPL_OS_BOOT=y + +Then rebuild U-Boot: + +$ make pico-hobbit-imx6ul_defconfig +$ make -j4 + +Launch UMS: +=> ums 0 mmc 0 + +Flash the new binaries: + +$ sudo dd if=SPL of=/dev/sdX bs=1k seek=1; sync +$ sudo dd if=u-boot.img of=/dev/sdX bs=1k seek=69; sync + +And then SPL binary will load and jump directly to the kernel: + +U-Boot SPL 2018.09-rc2-00156-g8c46f15-dirty (Sep 05 2018 - 16:24:05 -0300) +Trying to boot from MMC1 +[ 0.000000] Booting Linux on physical CPU 0x0 +[ 0.000000] Linux version 4.19.0-rc2-next-20180905-00001-gb805e2d (fabio@fabio-Latitude-E5450) (gcc version 5.4.0 20160609 (Ubuntu/Linaro 5.4.0-6ubuntu1~16.04.9)) #533 SMP Wed Sep 5 16:21:03 -03 2018 +[ 0.000000] CPU: ARMv7 Processor [410fc075] revision 5 (ARMv7), cr=10c5387d +[ 0.000000] CPU: div instructions available: patching division code +[ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache +[ 0.000000] OF: fdt: Machine model: Technexion Pico i.MX6UL Board +[ 0.000000] Memory policy: Data cache writealloc +[ 0.000000] cma: Reserved 64 MiB at 0x8c000000 +...