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Diffstat (limited to 'board/a3m071/README')
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diff --git a/board/a3m071/README b/board/a3m071/README deleted file mode 100644 index 112c47b60d..0000000000 --- a/board/a3m071/README +++ /dev/null @@ -1,80 +0,0 @@ ------------------------------------------------------------------------- -A3M071 board support ------------------------------------------------------------------------- - - -SPL NOR flash support: ----------------------- -To boot fast into the OS (Linux), this board port integrates the SPL -framework. This means, that a special, stripped-down version of -U-Boot runs in the beginning. In the case of the A3M071 board, this -SPL U-Boot version is less than 16 KiB big. This SPL U-Boot can either -boot the OS (Linux) or a "real", full-blown U-Boot. This detection -on whether to boot Linux or U-Boot is done by using the "boot_os" -environment variable. If "boot_os" is set to "yes", Linux will be -loaded and booted from the SPL U-Boot version. Otherwise, the -full-blown U-Boot version will be loaded and run. - -Enabling Linux booting: ------------------------ -From U-Boot: -=> setenv boot_os yes -=> saveenv - -From Linux: -$ fw_setenv boot_os yes - -Enabling U-Boot booting: ------------------------- -From U-Boot: -=> setenv boot_os no -=> saveenv - -From Linux: -$ fw_setenv boot_os no - - -Preparing Linux image(s) for booting from SPL U-Boot: ------------------------------------------------------ -To boot the Linux kernel from the SPL, the DT blob (fdt) needs to get -prepard/patched first. U-Boot usually inserts some dynamic values into -the DT binary (blob), e.g. autodetected memory size, MAC addresses, -clocks speeds etc. To generate this patched DT blob, you can use -the following command: - -1. Load fdt blob to SDRAM: -=> tftp 1800000 a3m071/a3m071.dtb - -2. Set bootargs as desired for Linux booting (e.g. flash_mtd): -=> run mtdargs addip2 addtty - -3. Use "fdt" commands to patch the DT blob: -=> fdt addr 1800000 -=> fdt boardsetup -=> fdt chosen - -4. Display patched DT blob (optional): -=> fdt print - -5. Save fdt to NOR flash: -=> erase fc180000 fc07ffff -=> cp.b 1800000 fc180000 10000 - -All this can be integrated into an environment command: -=> setenv upd_fdt 'tftp 1800000 a3m071/a3m071.dtb;run mtdargs addip addtty; \ - fdt addr 1800000;fdt boardsetup;fdt chosen;erase fc180000 fc07ffff; \ - cp.b 1800000 fc180000 10000' -=> saveenv - -After this, only "run upd_fdt" needs to get called to load, patch -and save the DT blob into NOR flash. - -Additionally, the Linux kernel image has to be saved uncompressed in -its uImage file (and not gzip compressed). This can be done with this -command: - -$ mkimage -A ppc -O linux -T kernel -C none -a 0 -e 0 \ - -n "Linux Kernel Image" -d vmlinux.bin uImage.uncompressed - ------------------------------------------------------------------------- -Stefan Roese, 2012-08-23 |