drm/i915/gt: Flush before changing register state

commit d5109f739c9f14a3bda249cb48b16de1065932f0 upstream.

Flush; invalidate; change registers; invalidate; flush.

Will this finally work on every device? Or will Baytrail complain again?

On the positive side, we immediately see the benefit of having hsw-gt1 in
CI.

Fixes: ace44e13e577 ("drm/i915/gt: Clear CACHE_MODE prior to clearing residuals")
Testcase: igt/gem_render_tiled_blits # hsw-gt1
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Akeem G Abodunrin <akeem.g.abodunrin@intel.com>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210125220247.31701-1-chris@chris-wilson.co.uk
(cherry picked from commit d30bbd62b1bfd9e0a33c3583c5a9e5d66f60cbd7)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Diego Calleja <diegocg@gmail.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/i915/gt/gen7_renderclear.c b/drivers/gpu/drm/i915/gt/gen7_renderclear.c
index c50b18d..e53b409 100644 (file)
--- a/drivers/gpu/drm/i915/gt/gen7_renderclear.c
+++ b/drivers/gpu/drm/i915/gt/gen7_renderclear.c
@@ -393,6 +393,7 @@ static void emit_batch(struct i915_vma * const vma,
                                                     desc_count);
 
        /* Reset inherited context registers */
+       gen7_emit_pipeline_flush(&cmds);
        gen7_emit_pipeline_invalidate(&cmds);
        batch_add(&cmds, MI_LOAD_REGISTER_IMM(2));
        batch_add(&cmds, i915_mmio_reg_offset(CACHE_MODE_0_GEN7));