It never quite worked despite the numerous workarounds, yet I still see people trying to use this hardware and filing bug reports. As we no longer even try to implement the workarounds, since 6a233c78878 (drm/i915/ringbuffer: kill snb blt workaround), simply disable the ring. v2: Add a message to inform the user about the limited capabilities of their pre-production hardware. Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk> --- drivers/gpu/drm/i915/i915_gem.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 3afba9d..db438f0 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -3739,6 +3739,22 @@ void i915_gem_init_ppgtt(struct drm_device *dev) } } +static bool +intel_enable_blt(struct drm_device *dev) +{ + if (!HAS_BLT(dev)) + return false; + + /* The blitter was dysfunctional on early prototypes */ + if (IS_GEN6(dev) && dev->pdev->revision < 8) { + DRM_INFO("BLT not supported on this pre-production hardware;" + " graphics performance will be degraded.\n"); + return false; + } + + return true; +} + int i915_gem_init_hw(struct drm_device *dev) { @@ -3762,7 +3778,7 @@ i915_gem_init_hw(struct drm_device *dev) goto cleanup_render_ring; } - if (HAS_BLT(dev)) { + if (intel_enable_blt(dev)) { ret = intel_init_blt_ring_buffer(dev); if (ret) goto cleanup_bsd_ring; -- 1.7.10