Backport more recent driver for Skylake and Cherryview graphics hardware

[Timo Aaltonen]

We need to support Skylake (SKL) and Cherryview (CHV) graphics in vivid, but the kernel driver is not fresh enough for proper support.

For the kernel the plan is to provide a separate driver module (i915_bpo) like for Haswell in quantal and Broadwell in trusty. The i915 driver in 3.19 is buggy and lacking features for SKL/CHV, so pulling the driver from current drm-intel-next branch would provide what'll end up in 4.1. The i915 drivers will be modified so that only i915_bpo loads on SKL machines, and only there. The driver will get further updates along the way, and possibly also rebased to a later kernel release.

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 3.19.0-12.12

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linux (3.19.0-12.12) vivid; urgency=low

  [ Andy Whitcroft ]

  * [Packaging] do_common_tools should always be on
  * [Packaging] Provides: virtualbox-guest-modules when appropriate
    - LP: #1434579

  [ Chris J Arges ]

  * Revert "SAUCE: ext4: disable ext4_punch_hole for indirect filesystems"
    - LP: #1292234

  [ Leann Ogasawara ]

  * Release Tracking Bug
    - LP: #1439803

  [ Timo Aaltonen ]

  * SAUCE: i915_bpo: Provide a backport driver for Skylake & Cherryview
    graphics
    - LP: #1420774
  * SAUCE: i915_bpo: Update intel_ips.h file location
    - LP: #1420774
  * SAUCE: i915_bpo: Only support Skylake and Cherryview with the backport
    driver
    - LP: #1420774
  * SAUCE: i915_bpo: Rename the backport driver to i915_bpo
    - LP: #1420774
  * i915_bpo: [Config] Enable CONFIG_DRM_I915_BPO=m
    - LP: #1420774
  * SAUCE: i915_bpo: Add i915_bpo_*() calls for ubuntu/i915
    - LP: #1420774
  * SAUCE: i915_bpo: Revert "drm/i915: remove unused
    power_well/get_cdclk_freq api"
    - LP: #1420774
  * SAUCE: i915_bpo: Add i915_bpo specific power well calls
    - LP: #1420774
  * SAUCE: Backport I915_PARAM_MMAP_VERSION and I915_MMAP_WC
    - LP: #1420774
  * SAUCE: Partial backport of drm/i915: Add ioctl to set per-context
    parameters
    - LP: #1420774
  * SAUCE: drm/i915: Specify bsd rings through exec flag
    - LP: #1420774
  * SAUCE: drm/i915: add I915_PARAM_HAS_BSD2 to i915_getparam
    - LP: #1420774
  * SAUCE: drm/i915: add component support
    - LP: #1420774
  * SAUCE: drm/i915: Add tiled framebuffer modifiers
    - LP: #1420774
  * SAUCE: Backport new displayable tiling formats
    - LP: #1420774
  * SAUCE: Backport drm_crtc_vblank_reset() helper
    - LP: #1420774
  * SAUCE: drm/i915: Add I915_PARAM_REVISION
    - LP: #1420774
  * SAUCE: drm/i915: Export total subslice and EU counts
    - LP: #1420774
  * SAUCE: i915_bpo: Revert drm/mm: Support 4 GiB and larger ranges
    - LP: #1420774

  [ Upstream Kernel Changes ]

  * drm/i915/skl: Split the SKL PCI ids by GT
    - LP: #1420774
  * drm: Reorganize probed mode validation
    - LP: #1420774
  * drm: Perform basic sanity checks on probed modes
    - LP: #1420774
  * drm: Do basic sanity checks for user modes
    - LP: #1420774
  * drm/atomic-helper: Export both plane and modeset check helpers
    - LP: #1420774
  * drm/atomic-helper: Again check modeset *before* plane states
    - LP: #1420774
  * drm/atomic: Introduce state->obj backpointers
    - LP: #1420774
  * drm: allow property validation for refcnted props
    - LP: #1420774
  * drm: store property instead of id in obj attachment
    - LP: #1420774
  * drm: get rid of direct property value access
    - LP: #1420774
  * drm: add atomic_set_property wrappers
    - LP: #1420774
  * drm: tweak getconnector locking
    - LP: #1420774
  * drm: add atomic_get_property
    - LP: #1420774
  * drm: Remove unneeded braces for single statement blocks
    - LP: #1420774
  * drm: refactor getproperties/getconnector
    - LP: #1420774
  * drm: add atomic properties
    - LP: #1420774
  * drm/atomic: atomic_check functions
    - LP: #1420774
  * drm: s...