On 29.05.2016 20:38, Daniel Gimpelevich wrote: > On Sun, 2016-05-29 at 12:53 +0200, Jonas Gorski wrote: >> This will break/won't compile for ZBOOT_APPENDED_DTB as __appended_dtb >> is >> part of the wrapping decompressor, and the kernel has no knowledge of >> this >> this symbol. > > If this were true, it wouldn't compile with the code you added to > compressed/head.S, either. You're referencing it as an external symbol, > which is exactly the same thing I'm doing here. There are two different __appended_dtb definitions: the one for the (uncompressed) kernel appended one that is visible to the kernel (in kernel/vmlinux.lds.S), and one in boot/compressed/ld.script that is visible only to the wrapping decompressor. Since the wrapping decompressor is built *after* the kernel was compiled and compressed, there is no way to tell the kernel where __appended_dtb is relative to the decompressor, so for ZBOOT_APPENDED_DTB you cannot reference __appended_dtb from kernel code. Your proposed > alternatives are functionally almost equivalent to your earlier rejected > patches: These weren't rejected, just deemed insufficient (mostly by me myself). And only to this one is similar: > https://patchwork.linux-mips.org/patch/7274/ But in contrast to this one, it doesn't populate initial_boot_params auto- matically, but instead still requires the mach to do that (by calling __dt_setup_arch()). I dropped that because IIRC at that time I read that initial_boot_params isn't supposed to be directly accessed. Also not populating initial_boot_params is IMHO better as just because a0 says -2 it doesn't mean a1 references a dtb - that should still be up to the mach to say that it expects a dtb to be passed. > https://patchwork.linux-mips.org/patch/7313/ This one was only missing alignment for the !SMP case but is otherwise equivalent to what is in the kernel now. Jonas
