Re: [U-Boot] Flat Image Tree and boot arguments

On 29 October 2014 19:52, Weiß Christoph Christoph.Weiss@ait.ac.at wrote:

Dear all,

I am trying to get my own build of U-Boot to boot Linux on a Jetson TK1 board. As we are pushing for verified boot I am using the Flat Image Tree (unifying kernel image, device tree blob, ...) to describe my system. U-Boot can load the ITB file and tries to start the kernel but the system hangs after this message.

I assume that this is because no boot arguments are passed to the kernel (the original startup adds loads of arguments) but I am a little dumbfounded on how to pass the arguments to the kernel. I tried setting the bootargs environment variable but this did not change the situation.

How do I pass kernel arguments to the kernel when using an ITB file?

Usually bootargs is part of dts itself check it on chosen node. No need to set it on u-boot if you use it from there.

Command line arguments (taken from the APPEND command of the examples extlinux.conf):

console=ttyS0,115200n8 console=tty1 no_console_suspend=1
lp0_vec=2064@0xf46ff000 video=tegrafb mem=1862M@2048M memtype=255 ddr_die=2048M@2048M
section=256M pmuboard=0x0177:0x0000:0x02:0x43:0x00 vpr=151M@3945M tsec=32M@3913M
otf_key=c75e5bb91eb3bd947560357b64422f85 usbcore.old_scheme_first=1 core_edp_mv=1150
core_edp_ma=4000 tegraid=40.1.1.0.0 debug_uartport=lsport,3 power_supply=Adapter
audio_codec=rt5640 modem_id=0 android.kerneltype=normal usb_port_owner_info=0
fbcon=map:1 commchip_id=0 usb_port_owner_info=0 lane_owner_info=6 emc_max_dvfs=0
touch_id=0@0 tegra_fbmem=32899072@0xad012000 board_info=0x0177:0x0000:0x02:0x43:0x00
root=/dev/mmcblk0p1 rw rootwait tegraboot=sdmmc gpt

Content of ITS file:

/dts-v1/;

/ {
            description = "Simple image with single Linux kernel and FDT blob";
            #address-cells = <1>;

            images {
                           kernel@1 {
                                           description = "Vanilla Linux kernel";
                                           data = /incbin/("./zImage");
                                           type = "kernel";
                                           arch = "arm";
                                           os = "linux";
                                           compression = "none";
                                           load = <0x81008000>;
                                           entry = <0x81008000>;
                                           hash@1 {
                                                           algo = "crc32";
                                           };
                                           hash@2 {
                                                           algo = "sha1";
                                           };
                           };
                           fdt@1 {
                                           description = "Flattened Device Tree blob";
                                           data = /incbin/("./tegra124-pm375.dtb");
                                           type = "flat_dt";
                                           arch = "arm";
                                           compression = "none";
                                           hash@1 {
                                                           algo = "crc32";
                                           };
                                           hash@2 {
                                                           algo = "sha1";
                                           };
                           };
            };

            configurations {
                           default = "conf@1";
                           conf@1 {
                                           description = "Boot Linux kernel with FDT blob";
                                           kernel = "kernel@1";
                                           fdt = "fdt@1";
                           };
            };
};

U-Boot Output:

Tegra124 (Jetson TK1) # fatload mmc 1 0x90000000 /kernel_fdt.itb
reading /kernel_fdt.itb
5946200 bytes read in 497 ms (11.4 MiB/s)
Tegra124 (Jetson TK1) # bootm 0x90000000
## Loading kernel from FIT Image at 90000000 ...
   Using 'conf@1' configuration
   Verifying Hash Integrity ... OK
   Trying 'kernel@1' kernel subimage
     Description:  Vanilla Linux kernel
     Type:         Kernel Image
     Compression:  uncompressed
     Data Start:   0x900000ec
     Data Size:    5910168 Bytes = 5.6 MiB
     Architecture: ARM
     OS:           Linux
     Load Address: 0x00000000
     Entry Point:  0x00000000

This looks odd - I guess host you created itb might have an issue. Check itb on host itself once you create through mkimage tool

$ mkimage -l kernel_fdt.itb

     Hash algo:    crc32
     Hash value:   c5b4b377
     Hash algo:    sha1
     Hash value:   f001007efe83f563425bfe0659186a32395c946c
   Verifying Hash Integrity ... crc32+ sha1+ OK
## Loading fdt from FIT Image at 90000000 ...
   Using 'conf@1' configuration
   Trying 'fdt@1' fdt subimage
     Description:  Flattened Device Tree blob
     Type:         Flat Device Tree
     Compression:  uncompressed
     Data Start:   0x905a30ac
     Data Size:    34678 Bytes = 33.9 KiB
     Architecture: ARM
     Hash algo:    crc32
     Hash value:   e466b23e
     Hash algo:    sha1
     Hash value:   ec909ae16e62233d0ed1e1f4c909085abc9b5879
   Verifying Hash Integrity ... crc32+ sha1+ OK
   Booting using the fdt blob at 0x905a30ac
   Loading Kernel Image ... OK
   Using Device Tree in place at 905a30ac, end 905ae821

Starting kernel ...

thanks!