Date: Tue, 22 Dec 2015 04:48:55 +0100 From: Sylvain Garrigues <sylgar@gmail.com> To: freebsd-arm@freebsd.org Subject: Booting the ELF kernel without ubldr on Raspberry Pi Message-ID: <C6819C94-DF61-447F-AC61-FD3E061A6F76@gmail.com>
next in thread | raw e-mail | index | archive | help
Hello, I’d like to boot FreeBSD directly with u-boot, without ubldr, using an image provided by the u-boot mkimage tool. The reason is simple: mkimage can deal with compressed kernels and will therefore speed my boot time. And I want to try it anyway, as it seems possible reading http://bsdcan.org/2008/schedule/attachments/49_2008_uboot_freebsd.pdf <http://bsdcan.org/2008/schedule/attachments/49_2008_uboot_freebsd.pdf>; and various other Before going there and using an mkimage, I’d like to boot the kernel image just with the same bootelf version provided by the sysutils/u-boot-rpi2 port. It doesn’t display anything and crashes (I think I can see « illegal instruction » just before the board reboots). I don’t understand why, and this is my first question. Then I looked at the mkimage utility, although we can specify and freebsd kernel type through the -O flag, the bootm command only understands linux and NetBSD. I guess I should use linux there? Thanks for your help, Sylvain PS: FYI, below is: 1/ info about my kernel (I can see the entry point is at 0xc0100100), copied into the fat partition # readelf -h /root/crochet/work/obj/arm.armv6/root/crochet/src/sys/RPI2/kernel ELF Header: Magic: 7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00 Class: ELF32 Data: 2's complement, little endian Version: 1 (current) OS/ABI: UNIX - System V ABI Version: 0 Type: EXEC (Executable file) Machine: ARM Version: 0x1 Entry point address: 0xc0100100 Start of program headers: 52 (bytes into file) Start of section headers: 6235080 (bytes into file) Flags: 0x5000202, has entry point, Version5 EABI, <unknown> Size of this header: 52 (bytes) Size of program headers: 32 (bytes) Number of program headers: 6 Size of section headers: 40 (bytes) Number of section headers: 38 Section header string table index: 35 [root@clad /usr/ports/sysutils/u-boot-rpi2]# 2/ the interesting part of my include/configs/rpi-common.h from u-boot: #define CONFIG_EXTRA_ENV_SETTINGS \ ENV_DEVICE_SETTINGS \ "loadaddr=0x02000000\0" \ "Fatboot=" \ "env exists loaderdev || env set loaderdev ${fatdev}; " \ "echo Booting from: ${fatdev} ${bootfile}; " \ "fatload ${fatdev} ${loadaddr} ${bootfile} && bootelf ${loadaddr}; " \ "\0" \ "preboot=" \ "fdt addr 0x100; " \ "env set bootfile kernel; " \ "env set fatdev 'mmc 0'; " \ "\0" #undef CONFIG_BOOTCOMMAND #define CONFIG_BOOTCOMMAND "run Fatboot" #undef CONFIG_PREBOOT #define CONFIG_PREBOOT "run preboot"
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?C6819C94-DF61-447F-AC61-FD3E061A6F76>