From: Fabio Estevam festevam@gmail.com
Improve the README by adding instructions on how to boot using Falcon mode, which allows the SPL to load the kernel directly, without using U-Boot proper.
Signed-off-by: Fabio Estevam festevam@gmail.com Signed-off-by: Otavio Salvador otavio@ossystems.com.br ---
board/technexion/pico-imx7d/README | 91 ++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+)
diff --git a/board/technexion/pico-imx7d/README b/board/technexion/pico-imx7d/README index 6aa0d25af5..4d57cdbfa8 100644 --- a/board/technexion/pico-imx7d/README +++ b/board/technexion/pico-imx7d/README @@ -66,3 +66,94 @@ 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=0x80008000 + +$ cp arch/arm/boot/uImage /tftpboot +$ cp arch/arm/boot/dts/imx7d-pico-pi.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} imx7d-pico-pi.dtb + +Get the kernel: +=> tftp ${loadaddr} uImage + +Write the kernel at 2MB offset: +=> mmc write ${loadaddr} 0x1000 0x5000 + +Setup the bootargs: +=> setenv bootargs 'console=ttymxc4,115200 root=/dev/mmcblk2p1 rootfstype=ext4 rootwait rw' + +Prepare args: +=> spl export fdt ${loadaddr} - ${fdt_addr} +## Booting kernel from Legacy Image at 80800000 ... + Image Name: Linux-5.2.14 + Image Type: ARM Linux Kernel Image (uncompressed) + Data Size: 9077544 Bytes = 8.7 MiB + Load Address: 80008000 + Entry Point: 80008000 + Verifying Checksum ... OK +## Flattened Device Tree blob at 83000000 + Booting using the fdt blob at 0x83000000 + Loading Kernel Image + Using Device Tree in place at 83000000, end 8300b615 +subcommand not supported +subcommand not supported + Using Device Tree in place at 83000000, end 8300e615 +Argument image is now in RAM: 0x83000000 +=> + +Write 1MB of args data (0x800 sectors) to 1MB offset (0x800 sectors): + +=> mmc write ${fdt_addr} 0x800 0x800 + +In order to boot with Falcon mode, activate the CONFIG_SPL_OS_BOOT +option in the defconfig + +--- a/configs/pico-imx7d_defconfig ++++ b/configs/pico-imx7d_defconfig +@@ -67,3 +67,4 @@ CONFIG_USB_GADGET_VENDOR_NUM=0x0525 + CONFIG_USB_GADGET_PRODUCT_NUM=0xa4a5 + CONFIG_CI_UDC=y + CONFIG_VIDEO=y ++CONFIG_SPL_OS_BOOT=y + +Then rebuild U-Boot: + +$ make pico-imx7d_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-dtb.img of=/dev/sdX bs=1k seek=69; sync + +And then SPL binary will load and jump directly to the kernel: + +U-Boot SPL 2019.10-rc3-00284-g001c8ea94a-dirty (Sep 10 2019 - 12:46:01 -0300) +Trying to boot from MMC1 +[ 0.000000] Booting Linux on physical CPU 0x0 +[ 0.000000] Linux version 5.2.14 (fabio@fabio-OptiPlex-7010) (gcc version 7.4.0 (Ubuntu/Linaro 7.4.0-1ubuntu1~18.04.1)) #30 SMP Wed Sep 10 12:36:27 -03 2019 +[ 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-IMX7D Board and PI baseboard +...