Hello,
Am Freitag, 19. Oktober 2018, 08:53:15 CEST schrieb Wolfgang Denk:
In message 2092760.TlMJupW03t@ada you wrote:
I played with the extlinux.conf format snippets from the U-Boot docs. Upstream extlinux docs are not really helpful, especially not for options regarding dtb> files. And I tried a config based on the Boot Loader Spec: Scanning mmc 2:1... Found /boot/extlinux/extlinux.conf Retrieving file: /boot/extlinux/extlinux.conf 366 bytes read in 268 ms (1000 Bytes/s) Ignoring unknown command: title Ignoring unknown command: version Ignoring unknown command: options Ignoring unknown command: linux Ignoring unknown command: devicetree
Am I right, U-Boot does not support that spec at all? Files are in different positions, and the keywords are all different? If so, then the U-Boot documentation is misleading (and people will be frustrated to follow the hints given in there).
It would definitely help if you tell us which actual command (sequence) you used to get this output, and what the exact content of this extlinux.conf was.
Okay first the content of /boot/extlinux/extlinux.conf from the root filesystem, which does not work (of course without additional linebreaks from my mail client):
title PTXdist version 4.9.133 options mtdparts=gpmi-nand:8M(fcb),7M(reserved)ro,512k(env1), 512k(env2),-(fs) ubi.mtd=fs console=ttymxc0,115200 rootwait rw root=/dev/ mmcblk0p1 linux /boot/zImage devicetree /boot/imx6dl-ttcore.dtb
As you might guess, I use ptxdist for building the BSP for an i.MX6 based platform. Currently everything is on a SD-Card and the system can boot from that card, if I load kernel image and dtb manually in U-Boot (or use another extlinux.conf).
Without such information, we cannot even guess what you did.
I was basically following the instructions from doc/README.distro so I read http://www.freedesktop.org/wiki/Specifications/BootLoaderSpec/ as mentioned in section "Boot Configuration Files" and set CONFIG_DISTRO_DEFAULTS=y and added the following to the board configuration header file in include/configs/
/* PHYS_ADDR is 0x10000000 for i.MX6S, * Kernel doc recommends to put dtb at 128 MiB, zImage above 32 MiB, * but below 128 MiB. So we put them there and scriptaddr after dtb. * We don't strictly need ramdisk_addr_r, but just set it to some * reasonable value according to doc/README.distro … * This should not collide with U-Boot which places itself at the * lowest 8k and something around 8 MB at the top of the memory, the * board currently has 512 MiB. */ #define MEM_LAYOUT_ENV_SETTINGS \ "kernel_addr_r=0x12000000\0" \ "fdt_addr_r=0x18000000\0" \ "scriptaddr=0x18100000\0" \ "pxefile_addr_r=0x18200000\0" \ "ramdisk_addr_r=0x18300000\0"
#define BOOT_TARGET_DEVICES(func) \ func(MMC, mmc, 0) \ func(MMC, mmc, 1) \ func(MMC, mmc, 2) \ func(UBIFS, ubifs, 0) \ func(USB, usb, 0)
#ifndef CONFIG_SPL_BUILD #include <config_distro_defaults.h> #include <config_distro_bootcmd.h> #endif
So in U-Boot env the following is set (this is populated by U-Boot itself by default, I removed non interesting lines and added some linebreaks):
boot_a_script=load ${devtype} ${devnum}:${distro_bootpart} ${scriptaddr} $ {prefix}${script}; source ${scriptaddr}
boot_extlinux=sysboot ${devtype} ${devnum}:${distro_bootpart} any $ {scriptaddr} ${prefix}extlinux/extlinux.conf
boot_net_usb_start=usb start boot_prefixes=/ /boot/ boot_script_dhcp=boot.scr.uimg boot_scripts=boot.scr.uimg boot.scr boot_targets=mmc0 mmc1 mmc2 ubifs0 usb0 bootcmd=run distro_bootcmd bootcmd_mmc0=setenv devnum 0; run mmc_boot bootcmd_mmc1=setenv devnum 1; run mmc_boot bootcmd_mmc2=setenv devnum 2; run mmc_boot bootcmd_ubifs0=setenv devnum 0; run ubifs_boot bootcmd_usb0=setenv devnum 0; run usb_boot distro_bootcmd=for target in ${boot_targets}; do run bootcmd_${target}; done mmc_boot=if mmc dev ${devnum}; then setenv devtype mmc; run scan_dev_for_boot_part; fi pxefile_addr_r=0x18200000 scan_dev_for_boot=echo Scanning ${devtype} ${devnum}:${distro_bootpart}...; for prefix in ${boot_prefixes}; do run scan_dev_for_extlinux; run scan_dev_for_scripts; done;
scan_dev_for_boot_part=part list ${devtype} ${devnum} -bootable devplist; env exists devplist || setenv devplist 1; for distro_bootpart in ${devplist}; do if fstype ${devtype} ${devnum}:${distro_bootpart} bootfstype; then run scan_dev_for_boot; fi; done
scan_dev_for_extlinux=if test -e ${devtype} ${devnum}:${distro_bootpart} $ {prefix}extlinux/extlinux.conf; then echo Found ${prefix}extlinux/ extlinux.conf; run boot_extlinux; echo SCRIPT FAILED: continuing...; fi
scan_dev_for_scripts=for script in ${boot_scripts}; do if test -e ${devtype} $ {devnum}:${distro_bootpart} ${prefix}${script}; then echo Found U-Boot script ${prefix}${script}; run boot_a_script; echo SCRIPT FAILED: continuing...; fi; done
What happens is what I wrote in the first mail. extlinux.conf is found and 'sysboot' fails because it ignores all the keywords.
What actually works is using an extlinux.conf similar to the examples in doc/ README.distro, but there are two things to mention:
1) keywords are used which are not mentioned in the upstream extlinux documentation 2) keywords from the bootloader spec don't work at all
So, although the idea to have a config file in the Linux filesystem an let the distribution set things in it, might be the same as in the Boot Loader Specification, my impression is, U-Boot does not follow the specification. Neither does it support multiple files (just /boot/extlinux/extlinux.conf works) nor the keywords specified?
An extlinux.conf that works is this:
label PTXdist kernel /boot/zImage fdtdir /boot append mtdparts=gpmi-nand:8M(fcb),7M(reserved)ro,512k(env1),512k(env2),- (UBI) ubi.mtd=UBI console=ttymxc0,115200 rootwait rw root=/dev/mmcblk0p1
I have to add, I currently still use U-Boot 2016.09, but I did a thorough research in master and the responsible code in cmd/pxe.c did not change from a functional point of view since 2016.09.
Greets Alex