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| author | Leah Rowe <leah@libreboot.org> | 2024-03-02 22:55:29 +0000 |
|---|---|---|
| committer | Leah Rowe <leah@libreboot.org> | 2024-03-02 23:12:54 +0000 |
| commit | 944cafa2306c1cd519c1599d249ae81b237fdfda (patch) | |
| tree | 33995569111ea5f6a7078f5187420ff6e5ca0105 /config/coreboot/default/patches/0004-lenovo-t60-make-64MiB-VRAM-the-default-in-cmos.defau.patch | |
| parent | db074b785ccbca67bf3de54ac4414fb72f1cdf8f (diff) | |
coreboot/haswell: make IOMMU a runtime option
It is now possible to disable the IOMMU on Haswell
boards, by doing this on your ROM image:
./nvramtool -C libreboot.rom -w iommu=Disable
To enable it again, do this:
./nvramtool -C libreboot.rom -w iommu=Enable
If not specified, the default behaviour is *on*.
A follow-up patch will turn IOMMU *off* by default,
on Dell OptiPlex 9020 SFF/MT, by setting it as such
in cmos.default. This is to make graphics cards work
properly to work around a bug when it's turned on.
Leaving the IOMMU enabled is recommended, if it works.
It works in most cases, including on 9020 SFF/MT when
using the Intel GPU without a graphics card inserted.
Signed-off-by: Leah Rowe <leah@libreboot.org>
Diffstat (limited to 'config/coreboot/default/patches/0004-lenovo-t60-make-64MiB-VRAM-the-default-in-cmos.defau.patch')
0 files changed, 0 insertions, 0 deletions