| Message ID | 1420471690-13541-13-git-send-email-bmeng.cn@gmail.com |
|---|---|
| State | Superseded |
| Delegated to: | Simon Glass |
| Headers | show |
Hi Bin, On 5 January 2015 at 08:28, Bin Meng <bmeng.cn@gmail.com> wrote: > Update README.x86 to include new build instructions for U-Boot as > the coreboot payload and testing considerations with coreboot. > > Signed-off-by: Bin Meng <bmeng.cn@gmail.com> > > --- > > Changes in v2: > - New patch to update REAME.x86 for coreboot support > > doc/README.x86 | 35 +++++++++++++++++++++++++++++++++++ > 1 file changed, 35 insertions(+) Looks good. Acked-by: Simon Glass <sjg@chromium.org> What method are you using to boot a kernel? I'm wondering how we document use cases like booting Ubuntu, booting from different boot devices, etc. Mostly this is zImage but we could link to x86-fit-boot.txt also. There is a syslinux approach used by many ARM boards now - e.g. see rpi.h which includes config_distro_defaults.h. Should we enable this for x86 too? Regards, Simon
Hi Simon, On Tue, Jan 6, 2015 at 9:50 AM, Simon Glass <sjg@chromium.org> wrote: > Hi Bin, > > On 5 January 2015 at 08:28, Bin Meng <bmeng.cn@gmail.com> wrote: >> Update README.x86 to include new build instructions for U-Boot as >> the coreboot payload and testing considerations with coreboot. >> >> Signed-off-by: Bin Meng <bmeng.cn@gmail.com> >> >> --- >> >> Changes in v2: >> - New patch to update REAME.x86 for coreboot support >> >> doc/README.x86 | 35 +++++++++++++++++++++++++++++++++++ >> 1 file changed, 35 insertions(+) > > Looks good. > > Acked-by: Simon Glass <sjg@chromium.org> Thanks for the fast response as always! Sorry, but I have to respin this patch due to I've found 3 typos (REAME.x86, aginst, u-boot-dtb.in) myself this morning. I must have had my brain cells tired last night :-< > What method are you using to boot a kernel? I'm wondering how we > document use cases like booting Ubuntu, booting from different boot > devices, etc. Mostly this is zImage but we could link to > x86-fit-boot.txt also. I am using zboot to boot a kernel bzImage with initramfs and nfs mounted as root. I have not tried to boot any distro out there. > There is a syslinux approach used by many ARM boards now - e.g. see > rpi.h which includes config_distro_defaults.h. Should we enable this > for x86 too? I will have a look. If we consider supporting syslinux, how about other bootloaders like grub? Regards, Bin
Hi Bin, On 5 January 2015 at 19:31, Bin Meng <bmeng.cn@gmail.com> wrote: > Hi Simon, > > On Tue, Jan 6, 2015 at 9:50 AM, Simon Glass <sjg@chromium.org> wrote: >> Hi Bin, >> >> On 5 January 2015 at 08:28, Bin Meng <bmeng.cn@gmail.com> wrote: >>> Update README.x86 to include new build instructions for U-Boot as >>> the coreboot payload and testing considerations with coreboot. >>> >>> Signed-off-by: Bin Meng <bmeng.cn@gmail.com> >>> >>> --- >>> >>> Changes in v2: >>> - New patch to update REAME.x86 for coreboot support >>> >>> doc/README.x86 | 35 +++++++++++++++++++++++++++++++++++ >>> 1 file changed, 35 insertions(+) >> >> Looks good. >> >> Acked-by: Simon Glass <sjg@chromium.org> > > Thanks for the fast response as always! Sorry, but I have to respin > this patch due to I've found 3 typos (REAME.x86, aginst, > u-boot-dtb.in) myself this morning. I must have had my brain cells > tired last night :-< > >> What method are you using to boot a kernel? I'm wondering how we >> document use cases like booting Ubuntu, booting from different boot >> devices, etc. Mostly this is zImage but we could link to >> x86-fit-boot.txt also. > > I am using zboot to boot a kernel bzImage with initramfs and nfs > mounted as root. I have not tried to boot any distro out there. > >> There is a syslinux approach used by many ARM boards now - e.g. see >> rpi.h which includes config_distro_defaults.h. Should we enable this >> for x86 too? > > I will have a look. If we consider supporting syslinux, how about > other bootloaders like grub? Could do, I'm not sure how to run it, but I suppose it's not that hard. Regards, Simon
diff --git a/doc/README.x86 b/doc/README.x86 index 5fab044..da0c712 100644 --- a/doc/README.x86 +++ b/doc/README.x86 @@ -32,6 +32,21 @@ on other architectures, like below: $ make coreboot-x86_defconfig $ make all +Note this default configuration will build a U-Boot payload for the Link board. +To build a coreboot payload aginst another board, you can change the build +configuration during the 'make menuconfig' process. + +x86 architecture ---> + ... + (chromebook_link) Board configuration file + (chromebook_link) Board Device Tree Source (dts) file + (0x19200000) Board specific Cache-As-RAM (CAR) address + (0x4000) Board specific Cache-As-RAM (CAR) size + +Change the 'Board configuration file' and 'Board Device Tree Source (dts) file' +to point to a new board. You can also change the Cache-As-RAM (CAR) related +settings here if the default values do not fit your new board. + Building ROM version of U-Boot (hereafter referred to as u-boot.rom) is a little bit tricky, as generally it requires several binary blobs which are not shipped in the U-Boot source tree. Due to this reason, the u-boot.rom build is @@ -93,6 +108,26 @@ Now you can build U-Boot and obtaim u-boot.rom $ make crownbay_defconfig $ make all +Test with coreboot +------------------ +For testing U-Boot as the coreboot payload, there are things that need be paid +attention to. coreboot supports loading an ELF executable and a 32-bit plain +binary, as well as other supported payloads. With the default configuration, +U-Boot is set up to use a separate Device Tree Blob (dtb). As of today, the +generated u-boot-dtb.in needs to be packaged by the cbfstool utility (a tool +provided by coreboot) manually as coreboot's 'make menuconfig' does not provide +this capability yet. The command is as follows: + +# in the coreboot root directory +$ ./build/util/cbfstool/cbfstool build/coreboot.rom add-flat-binary \ + -f u-boot-dtb.bin -n fallback/payload -c lzma -l 0x1110000 -e 0x1110015 + +Make sure 0x1110000 matches CONFIG_SYS_TEXT_BASE and 0x1110015 matches the +symbol address of _start (in arch/x86/cpu/start.S). + +If you want to use ELF as the coreboot payload, change U-Boot configuration to +use CONFIG_OF_EMBED. + CPU Microcode ------------- Modern CPU usually requires a special bit stream called microcode [5] to be
Update README.x86 to include new build instructions for U-Boot as the coreboot payload and testing considerations with coreboot. Signed-off-by: Bin Meng <bmeng.cn@gmail.com> --- Changes in v2: - New patch to update REAME.x86 for coreboot support doc/README.x86 | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+)