4.14-stable review patch. If anyone has any objections, please let me know.
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From: Chris Wilson chris@chris-wilson.co.uk
commit c5ba5b24657e473b1c64b0a614b168a635a2c935 upstream.
We also see the delayed GTT write issue on i915g/i915gm, so let's presume that it is a universal problem for all !llc machines, and that we just haven't yet noticed on g33, gen4 and gen5 machines.
v2: Use a register that exists on all platforms
Testcase: igt/gem_mmap_gtt/coherency # i915gm References: https://bugs.freedesktop.org/show_bug.cgi?id=102577 Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Ville Syrjälä ville.syrjala@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20170907184520.5032-1-chris@ch... Reviewed-by: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Sudip Mukherjee sudipm.mukherjee@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/i915_gem.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -687,10 +687,10 @@ flush_write_domain(struct drm_i915_gem_o
switch (obj->base.write_domain) { case I915_GEM_DOMAIN_GTT: - if (INTEL_GEN(dev_priv) >= 6 && !HAS_LLC(dev_priv)) { + if (!HAS_LLC(dev_priv)) { intel_runtime_pm_get(dev_priv); spin_lock_irq(&dev_priv->uncore.lock); - POSTING_READ_FW(RING_ACTHD(dev_priv->engine[RCS]->mmio_base)); + POSTING_READ_FW(RING_HEAD(dev_priv->engine[RCS]->mmio_base)); spin_unlock_irq(&dev_priv->uncore.lock); intel_runtime_pm_put(dev_priv); }