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@@ -36,7 +36,11 @@ To build this on Fedora Linux: * No rescue vmlinuz. * No secure boot possible for this ISO for now, as the platform used is `efi` and not `uefi`. * No GRUB auto hidden menu. Trying to have the menu hidden results in system restarting after trying to boot it. -* Hardware video encoding/decoding needs a firmware blob the image cannot ship. The `qcom/vpu/vpu30_p1_s7.mbn` that `linux-firmware` provides is signed with Qualcomm's SecTools *test* key chain, which a retail Surface's TrustZone rejects -- `qcom_scm_pas_init_image()` fails and the kernel logs `qcom-iris aa00000.video-codec: error -22 initializing firmware`. The production-signed build of the same firmware ships with Windows, so if you kept the Windows ARM64 partition, copy `qcvss8380_pa.mbn` out of `/path/to/mounted/windows/drive/Windows/System32/DriverStore/FileRepository/qcdx8380.inf_arm64_*/` into `/lib/firmware/qcom/x1p42100/Microsoft/Surface12/`. The kernel's device tree already points `iris` at that path. +* Hardware video encoding/decoding needs a firmware blob the image is not allowed to ship. The `qcom/vpu/vpu30_p1_s7.mbn` that `linux-firmware` provides is the same codec signed with Qualcomm's SecTools *test* key chain, which a retail Surface's TrustZone rejects -- `qcom_scm_pas_init_image()` fails and the kernel logs `qcom-iris aa00000.video-codec: error -22 initializing firmware`. The production-signed build exists only inside Microsoft's Surface driver package, which grants no redistribution right, so what ships here is the means and not the blob: + * If you kept the Windows ARM64 partition, `surface-video-firmware.service` finds it on the first boot after install and copies `qcvss8380_pa.mbn` out of its DriverStore. Nothing to do. + * If Windows is gone, download the [Surface Pro 12-inch driver pack](https://www.microsoft.com/en-us/download/details.aspx?id=108199) (~500 MB MSI) and run `sudo surface-video-firmware.sh -m /path/to/SurfacePro_12in_*.msi`. There is no automatic download: the Download Center hands out per-session links. + + The kernel's device tree already points `iris` at `/lib/firmware/qcom/x1p42100/Microsoft/Surface12/qcvss8380_pa.mbn`, so the driver picks it up as soon as it is there. * Suspend on Snapdragon X is still very unstable. No deep sleep is available, so `mem_sleep_default=s2idle` was set. Even that leads to compromises as suspending via GNOME results in hard freeze, so the default power button behavior was changed to `interactive` and should not be changed back to `suspend`. ## Image variants |