Hi, On 08/10/2014 11:00 PM, Karsten Merker wrote: > Hello, > > in the following email you can find a patch to populate the > default environment for sunxi-based systems about which I would > apprechiate your opinion. > > With the current progress in mainlining sunxi platform support, > mainline u-boot will probably soon be able to replace > u-boot-sunxi (https://github.com/linux-sunxi/u-boot-sunxi) for > many use cases. Currently the default environment in mainline > u-boot for sunxi-based systems is rather bare; the only > predefined variable is bootm_size (which is required for proper > initrd- and dtb-relocation). U-boot-sunxi predefines a set of > environment variables which are commonly used by existing boot > scripts and also offers a predefined bootcmd for automatic search > and execution of bootscripts. I think that to facilitate using > mainline u-boot as a drop-in replacement for u-boot-sunxi, > mainline u-boot should provide similar defaults. > > The original environment in u-boot-sunxi was written for an older > u-boot release and does not make use of modern u-boot features > (e.g. it uses hardcoded filesystem-specific load commands), so > just copying the environment 1:1 to mainline u-boot does not make > sense IMHO. My patch tries to implement the minimum required for > autobooting existing boot scripts with more modern u-boot functions. > > In addition to that, the patch defines some standard environment > variables which are commonly defined on other u-boot platforms, > but which have not been defined by u-boot-sunxi, in particular > kernel_addr_r, ramdisk_addr_r and fdt_addr_r. Debian supports a > wide range of armhf system and tries to unify support for the > different platforms as good as possible. Having the same > predefined variables with (platform-specific) load addresses on > all platforms would help us a lot with regard to generic boot > scripts and simplified user documentation. > > Regarding the actual values for the various load addresses I am > not in all cases perfectly sure about the best variant. > Following is the reasoning for my choices: > > - fdt_addr_r > > U-boot-sunxi loads the FEX binary (Allwinner's proprietary > hardware description format for their android kernels, i.e. > a file functionally roughly equivalent to a dtb) to address > 0x43000000, so I guess using the same for the dtb makes > sense. > > - scriptaddr > > has historically been expected to be 0x44000000; some old boot > scripts assume this address. > > - kernel_addr_r and ramdisk_addr_r > > Allwinner has historically loaded their kernels to 0x48000000 > (system specific kernels with all drivers compiled in, no initrd). > > Debian has been using 0x46000000 for the kernel and 0x48000000 > for the initrd. These values work well in practice, so I have > used them in the patch, but if there are reasons to change them, > I am happy to do so. > > Comments welcome :-).
Thanks for this patch, but this does the same as a series I've already pending, see: https://github.com/jwrdegoede/u-boot-sunxi/commits/next I've not yet send a pull-request for this because it uses the new generic $bootcmd support: https://github.com/jwrdegoede/u-boot-sunxi/commit/34e421a155c83c52f6e6edb2594458af27ef7517 This commit has just been merged by Tom Rini, so right now these patches are good to go. I'll send a pull-request for them soon. Let me know if somehow these patches won't work for Debian. One of the goals of the generic $bootcmd support is that distributions can just drop an extlinux.conf in the boot partition, and then u-boot will automatically find it and do the right thing. Regards, Hans _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
