Dear Branden,
Am 26.05.21 um 04:25 schrieb Branden Waldner:
On 5/25/21, Paul Menzel wrote:
Am 22.05.21 um 20:03 schrieb Branden Waldner:
On 5/21/21, Arthur Heymans arthur@aheymans.xyz wrote:
Thanks for sharing your findings. The flash is 256K big, which is quite small these days. When building coreboot with default settings but without a payload I find that there is 69K empty space left for payloads.
Some future developments I have been working on might give a bit more breathing space.
- I want to make romstage optional and include the sources in the
bootblock: That should shave off roughly 10K of romstage.
- I have compressing postcar working (maybe you can also disable the
postcar console to reduce size). That's also 2-3k size gains at likely the const of a tiny bit of boot performance on this platform.
- I also have some WIP code to merge postcar into ramstage which would
save 15k.
Maybe on coreboot release 4.15 you will have a better time building a fully working image with the default configuration.
I didn't realize there was development going on to save rom space, that's good to know.
I just built the asus/p2b from commit d981c490 (mb/google/mancomb: Enable some PCIe power saving features) with the Debian sid/unstable toolchain (gcc (Debian 10.2.1-6) 10.2.1 20210110).
There, wasn’t enough space to add SeaBIOS’ configuration file to CBFS. Not setting `INCLUDE_CONFIG_FILE`, there wasn’t any error, the coreboot image built fine.
FMAP REGION: COREBOOT Name Offset Type Size Comp cbfs master header 0x0 cbfs header 32 none fallback/romstage 0x80 stage 17336 none cpu_microcode_blob.bin 0x44c0 microcode 83968 none fallback/ramstage 0x18d00 stage 53376 LZMA (112168 decompressed) build_info 0x25e00 raw 89 none fallback/dsdt.aml 0x25e80 raw 5514 none cmos_layout.bin 0x27440 cmos_layout 704 none fallback/postcar 0x27740 stage 16888 none fallback/payload 0x2b980 simple elf 69886 none (empty) 0x3cac0 null 1956 none bootblock 0x3d280 bootblock 11088 noneBuilding with Jacob’s link time optimization changes [1], which he thankfully rebased, saved 13 kB, so the configuration file would fit in too.
FMAP REGION: COREBOOT Name Offset Type Size Comp cbfs master header 0x0 cbfs header 32 none fallback/romstage 0x80 stage 14752 none cpu_microcode_blob.bin 0x3ac0 microcode 83968 none fallback/ramstage 0x18300 stage 46277 LZMA (95496 decompressed) build_info 0x23840 raw 89 none fallback/dsdt.aml 0x238c0 raw 5514 none cmos_layout.bin 0x24e80 cmos_layout 704 none fallback/postcar 0x25180 stage 14872 none fallback/payload 0x28c00 simple elf 69886 none (empty) 0x39d40 null 15012 none bootblock 0x3d800 bootblock 9664 none(If you have a recovery option and some spare time, it’d be great if you tested the LTO patches.)
I could probably test them out, though I'm not sure I'll get around to it right away.
No hurry.
Does the patch set require anything special? It looks like it just uses a Kconfig to add the choice to use the LTO compiler options.
Sorry, I only noted “(whole series)” below at the reference. You need the changes listed on the right side in Gerrit. Gerrit’s download options allow you to fetch those with one command.
Does it work with the coreboot crossgcc or should I try using the system compiler on the build machine like you did (Debian sid x86_64), or maybe it would be best to try both?
More tests are always welcome, but coreboot’s crossgcc should work.
My recovery method isn't very good right now though. If I've got a boot failure I change the rom to a known good one and hot swap back to the chip with the bad rom to reflash it. It's pretty annoying, but I haven't messed up yet.
Speaking from experience, three chips would be better. ;-) But, I used the same method for years, and there are worse methods (if no socket is there).
I did try to get some (cheap) zif adapter sockets, but they didn't work out for me - not enough space and they don't seat in a socket, they seem to be meant to be soldered to a board, not used in a socket.
Sorry, I do not know anything about that.
I haven't had much luck in finding options for recovery. Ideally I'd like something like the dual switched bios in the old wiki but toggle-able electronically ie. gpio pin from spare router w/ Openwrt. That sounds like a lot of work though and I never managed to find much online as examples.
Yes, it probably depends on the board. I just remember Alexandru Gagniuc’ VultureProg [2].
Kind regards,
Paul
(whole series)[2]:
https://blogs.coreboot.org/blog/2013/07/25/vultureprog-equipped-for-galactic...