Date: Mon, 27 May 2019 22:46:13 -0600 From: Warner Losh <imp@bsdimp.com> To: Nathan Whitehorn <nwhitehorn@freebsd.org> Cc: Eric McCorkle <eric@metricspace.net>, FreeBSD Hackers <freebsd-hackers@freebsd.org>, FreeBSD Current <freebsd-current@freebsd.org>, =?UTF-8?Q?Edward_Tomasz_Napiera=C5=82a?= <trasz@freebsd.org> Subject: Re: FreeBSD and Coreboot Message-ID: <CANCZdfoTgyxOoKWqYBUh3ck_Jww3xf6SbKu6vC5a9erH4qOw0Q@mail.gmail.com> In-Reply-To: <79c249c0-e6b0-a584-ad23-c9a4f57ff3c1@freebsd.org> References: <4a6b0f1e-64ec-6b83-b43b-f9791ec8428f@metricspace.net> <CAFLM3-rMJmPs4OvRczDtiENtYaSpODRGQaFuONc%2BouxchJQDxw@mail.gmail.com> <1452db0c-1210-3230-c044-bc682e7e1745@metricspace.net> <3aa00c6b-2502-ffad-c915-a833292882bd@freebsd.org> <CANCZdfovLtbwN-mLHSZKNsFwcjX0NzK82TFZunuGJDyHVj709w@mail.gmail.com> <79c249c0-e6b0-a584-ad23-c9a4f57ff3c1@freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, May 27, 2019, 10:44 PM Nathan Whitehorn <nwhitehorn@freebsd.org> wrote: > > > On 2019-05-27 19:14, Warner Losh wrote: > > On Mon, May 27, 2019, 7:18 PM Nathan Whitehorn <nwhitehorn@freebsd.org> > > wrote: > > > >> > >> On 2019-05-27 15:50, Eric McCorkle wrote: > >>> On 5/27/19 5:53 PM, Edward Napierala wrote: > >>>> On Mon, 27 May 2019 at 16:14, Eric McCorkle <eric@metricspace.net> > >> wrote: > >>>> [..] > >>>> > >>>>> My plan is roughly this: > >>>>> > >>>>> * Refurbish the GRUB port, get it working again in QEMU (possibly on > >> one > >>>>> of my machines), also possibly push a patch to GRUB to use the > keybufs > >>>>> mechanism to pass in GELI keys. > >>>>> > >>>>> * Get coreboot with GRUB/Seabios booting FreeBSD in QEMU > >>>>> > >>>>> * Possibly create a coreboot port (uncertain how this would work, > since > >>>>> Coreboot has its own extensive config menu) > >>>>> > >>>>> * Hold my breath and test it out on real hardware (I have a Librem 13 > >> r1 > >>>>> for this purpose) > >>>>> > >>>>> * Possibly try getting the FreeBSD kernel to work as a coreboot > >> payload. > >>>> Out of curiosity - why the kernel and not loader(8)? > >>>> > >>> If I understand coreboot correctly, loader would have to directly > >>> manipulate devices _without a BIOS_. That is, it would have to have an > >>> entire device detection/interface layer, which I don't believe is the > >>> case today. > >>> > >>> At least in the EFI case, loader is talking through the system's EFI > >>> implementation, which takes care of all that for you. BIOS works in a > >>> similar way. My sense is getting loader to the point where it could be > >>> a coreboot (without Seabios/GRUB/Tianocore) would be quite an > >> undertaking. > >> On IBM PowerNV systems, which also don't provide interfaces to a > >> second-stage loader, we just abandoned loader(8). It's way too much > work. > >> > > How do you use tunables and loadable modules? > > > > Warner > > > > The firmware on PowerNV has a way to write tunables to the device-tree, > which we rehydrate into something that looks like it came from loader. > > We don't usefully support loadable modules at the moment. The firmware > can optionally load exactly one file from the boot filesystem and pass > it to the kernel (for Linux, the initrd). There are a couple of ways to > imagine exploiting this for kernel modules, but all of them are kind of > crummy. > Now that the loader supports a ram disk, we are almost to something useful... but yea, almost and crummy often go hand in hand. Warner >
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CANCZdfoTgyxOoKWqYBUh3ck_Jww3xf6SbKu6vC5a9erH4qOw0Q>