r400.md 2.4 KB
title: ThinkPad R400 x-toc-enable: true ...
It is believed that all or most R400 laptops are compatible. See notes about CPU compatibility for potential incompatibilities.
There are two possible flash chip sizes for the R400: 4MiB (32Mbit) or 8MiB (64Mbit). This can be identified by the type of flash chip below the palmrest: 4MiB is SOIC-8, 8MiB is SOIC-16.
The R400 laptops come with the ME (and sometimes AMT in addition) before flashing libreboot. Libreboot disables and removes it by using a modified descriptor: see ../install/ich9utils.md (contains notes, plus instructions)
Flashing instructions can be found at ../install/#flashrom
EC update {#ecupdate}
It is recommended that you update to the latest EC firmware version. The EC firmware is separate from libreboot, so we don't actually provide that, but if you still have Lenovo BIOS then you can just run the Lenovo BIOS update utility, which will update both the BIOS and EC version. See:
NOTE: this can only be done when you are using Lenovo BIOS. How to update the EC firmware while running libreboot is unknown. Libreboot only replaces the BIOS firmware, not EC.
Updated EC firmware has several advantages e.g. bettery battery handling.
Compatibility (without blobs) {#compatibility_noblobs}
Hardware virtualization (vt-x) {#hwvirt}
The R400, when run without CPU microcode updates in coreboot, currently kernel panics if running QEMU with vt-x enabled on 2 cores for the guest. With a single core enabled for the guest, the guest panics (but the host is fine). Working around this in QEMU might be possible; if not, software virtualization should work fine (it's just slower).
On GM45 hardware (with libreboot), make sure that the kvm and kvm_intel kernel modules are not loaded, when using QEMU.
The following errata datasheet from Intel might help with investigation: http://download.intel.com/design/mobile/specupdt/320121.pdf
The R400 is almost identical to the X200, code-wise. See x200.md.
TODO: put hardware register logs here like on the X200 and T400 page.