KernelTree

The Petitboot kernel is currently based on the 4.2 series.

Submitting a patch

If you require a patch added to the firmware, follow these steps:

1. Submit your patch upstream. It doesn't need to be upstream, but it should be on it's way
2. Send a pull request or a git format-patch formatted patch series to [email protected]

Bug fixes

Whenever a stable release is tagged in https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/, we will rebase our patches on top of that and create a new release.

Versioning

Versions are the upstream version number, followed by -openpowerN, where N is the revision that counts up from 1 for the given upstream version number. These versions will be present as tags in the git repository hosted at https://github.com/open-power/linux.

Tree and patches

The kernel tree hosted at https://github.com/open-power/linux contains the current release plus a set of patches that we carry. Ideally there would be no patches carried, as everything should be upstream.

We take the commits in this tree between the upstream tag and the openpower tag and generate a series of patches that are imported into the op-build Buildroot overlay, and placed in op-build/openpower/linux. op-build then fetches the upstream tarball and applies these patches. This way we don't have to clone an entire tree when doing an op-build build.

Patches in the tree

The following patches are remaining after rebasing on 4.2.

Patches we carry

xhci: Use xhci_pci_remove for xhci device shutdown
Revert "powerpc: Reject binutils 2.24 when building little endian"

Upstream in 4.3

powerpc/kexec: Reset HILE before kexec_sequence
powerpc/kexec: Reset secondary cpu endianess before kexec
xhci: do not halt the secondary HCD (a v4.2.4 stable backport removed the need for this patch)

Upstream in 4.4

aacraid: Update driver version
aacraid: Use pci_enable_msix_range()
aacraid: Reset irq affinity hints
aacraid: IOCTL fix
aacraid: Enable 64bit write to controller register
aacraid: Tune response path if IsFastPath bit set
aacraid: Change interrupt mode to MSI for Series 6
aacraid: Add Power Management support
aacraid: Fix for LD name and UID not exposed to OS

Dropped patches

drm/ast: Default to 8bpp on big endian (we are now LE, and upstream don't want this as-is)