9.3 KiB
Qubes requires IOMMU to be turned on. Please now read the next section. Qubes WILL work, if you configure Libreboot as directed below, but otherwise it will fail by default. This is because Libreboot disables the IOMMU by default, on this board.
Graphics cards and IOMMU
IOMMU is buggy for some reason (we don't know why yet), when you plug in a graphics card. The graphics card simply won't work. On some of them, you can use the console but as soon as you start xorg, it will just b0rk.
Current Libreboot revisions disable IOMMU by default, on this board. The coreboot code for initialising IOMMU was modified by the Libreboot project, to make it a toggle. IOMMU works fine if you use only Intel graphics.
The way coreboot works is this: if vt-d is present on the CPU, it enables an
IOMMU, and only if vt-d is present. This is still the behaviour in Libreboot,
but Libreboot adds an additional check: if iommu is not set in nvram, it
defaults to on, but if it's set to disabled, then IOMMU is not initialised.
On all other Haswell boards, LIbreboot enables IOMMU by default. To enable it on the 9020, do this on your ROM:
nvramtool -C libreboot.rom -w iommu=Enable
Then flash the ROM image. You can find nvram
under src/coreboot/default/util/nvramtool. Do this in lbmk if you don't
already havse src/coreboot/default/:
./update trees -f coreboot default
Then do this:
make -C src/coreboot/default/util/nvramtool
The binary nvramtool will then live in that directory. More information
available in Libreboot build instructions. Information about
dumping/flashing the ROM can be found
in Libreboot flashing instructions
and Libreboot external flashing instructions.
NOTE: If IOMMU is enabled, you can still use a graphics card, but you must
pass this on the Linux cmdline paramaters: iommu=off
NOTE2: Libreboot uses a static option table on all boards that have nvram,
which is why you must use the -C option on your ROM, to change the static
table that is baked into it.
On current lbmk master, graphics cards do work. The option to hide PEG devices from MRC was disabled. Now when you insert a graphics card, the onboard Intel GPU is disabled and the graphics card is used instead.
Here is an example of the type of errors we got when testing graphics cards with IOMMU enabled:
https://av.vimuser.org/error.jpg
We believe the native MRC replacement may work better on graphics card with IOMMU turned on. This will be enabled in a future Libreboot release, if not already supported.
7020 compatibility
7020/9020 MT each have the same motherboard. Flash the 9020 ROM from Libreboot on your 7020, and it will work.
Ditto 7020/9020 SFF, it's the same motherboard. However, Libreboot provides separate targets for MT and SFF.
Build ROM image from source
For the MT variant (7020 MT and 9020 SFF):
./build roms dell9020mt_12mb
For the SFF variant (7020 MT and 7020 SFF):
./build roms dell9020sff_12mb
It is important that you choose the right one. The MT variant is the full MTX tower.
Installation
Insert binary files
If you're using a release ROM, please ensure that you've inserted extra firmware required refer to the guide for that. (failure to adhere to this advice will result in a bricked machine)
Libreboot's build system automatically downloads and processes these files if you build Libreboot from source, but the same logic that it uses must be re-run if you're using a release image.
Set MAC address
This platform uses an Intel Flash Descriptor, and defines an Intel GbE NVM region. As such, release/build ROMs will contain the same MAC address. To change the MAC address, please read nvmutil documentation.
Flash a ROM image (software)
If you're already running Libreboot, and you don't have flash protection turned on, internal flashing is possible.
Flash a ROM image (hardware)
REMOVE all power sources and connectors from the machine, before doing this. This is to prevent short circuiting and power surges while flashing.
For general information, please refer to 25xx NOR flash instructions - that page refers to use of socketed flash.
There are two SOIC-8 chips. You can split up your 12MB ROM image like so:
dd if=libreboot.rom of=4mb.rom bs=1M skip=8
dd if=libreboot.rom of=8mb.rom bs=1M count=8
The side cover comes off easily, and you can find the flash ICs next to the RAM.
Here's the SOIC8 ICs being flashed:
Enjoy!