• Sourab Gupta's avatar
    drm/i915: Replaced Blitter ring based flips with MMIO flips · 84c33a64
    Sourab Gupta authored
    This patch enables the framework for using MMIO based flip calls,
    in contrast with the CS based flip calls which are being used currently.
    
    MMIO based flip calls can be enabled on architectures where
    Render and Blitter engines reside in different power wells. The
    decision to use MMIO flips can be made based on workloads to give
    100% residency for Media power well.
    
    v2: The MMIO flips now use the interrupt driven mechanism for issuing the
    flips when target seqno is reached. (Incorporating Ville's idea)
    
    v3: Rebasing on latest code. Code restructuring after incorporating
    Damien's comments
    
    v4: Addressing Ville's review comments
        -general cleanup
        -updating only base addr instead of calling update_primary_plane
        -extending patch for gen5+ platforms
    
    v5: Addressed Ville's review comments
        -Making mmio flip vs cs flip selection based on module parameter
        -Adding check for DRIVER_MODESET feature in notify_ring before calling
         notify mmio flip.
        -Other changes mostly in function arguments
    
    v6: -Having a seperate function to check condition for using mmio flips (Ville)
        -propogating error code from i915_gem_check_olr (Ville)
    
    v7: -Adding __must_check with i915_gem_check_olr (Chris)
        -Renaming mmio_flip_data to mmio_flip (Chris)
        -Rebasing on latest nightly
    
    v8: -Rebasing on latest code
        -squash 3rd patch in series(mmio setbase vs page flip race) with this patch
        -Added new tiling mode update in intel_do_mmio_flip (Chris)
    
    v9: -check for obj->last_write_seqno being 0 instead of obj->ring being NULL in
    intel_postpone_flip, as this is a more restrictive condition (Chris)
    
    v10: -Applied Chris's suggestions for squashing patches 2,3 into this patch.
    These patches make the selection of CS vs MMIO flip at the page flip time, and
    make the module parameter for using mmio flips as tristate, the states being
    'force CS flips', 'force mmio flips', 'driver discretion'.
    Changed the logic for driver discretion (Chris)
    
    v11: Minor code cleanup(better readability, fixing whitespace errors, using
    lockdep to check mutex locked status in postpone_flip, removal of __must_check
    in function definition) (Chris)
    Reviewed-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
    Signed-off-by: default avatarSourab Gupta <sourab.gupta@intel.com>
    Signed-off-by: default avatarAkash Goel <akash.goel@intel.com>
    Tested-by: Chris Wilson <chris@chris-wilson.co.uk> # snb, ivb
    [danvet: Fix up parameter alignement checkpatch spotted.]
    Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
    84c33a64
intel_drv.h 33.1 KB