diff mbox

[v6,2/6] drm/i915/gen8: Re-order init pipe_control in lrc mode

Message ID 1434735435-14728-3-git-send-email-arun.siluvery@linux.intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

arun.siluvery@linux.intel.com June 19, 2015, 5:37 p.m. UTC 
Some of the WA applied using WA batch buffers perform writes to scratch page.
In the current flow WA are initialized before scratch obj is allocated.
This patch reorders intel_init_pipe_control() to have a valid scratch obj
before we initialize WA.

v2: Check for valid scratch page before initializing WA as some of them
perform writes to it.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
---
 drivers/gpu/drm/i915/intel_lrc.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

Comments

Chris Wilson June 19, 2015, 5:58 p.m. UTC | #1 
On Fri, Jun 19, 2015 at 06:37:11PM +0100, Arun Siluvery wrote:
> Some of the WA applied using WA batch buffers perform writes to scratch page.
> In the current flow WA are initialized before scratch obj is allocated.
> This patch reorders intel_init_pipe_control() to have a valid scratch obj
> before we initialize WA.
> 
> v2: Check for valid scratch page before initializing WA as some of them
> perform writes to it.
> 
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Dave Gordon <david.s.gordon@intel.com>
> Signed-off-by: Michel Thierry <michel.thierry@intel.com>
> Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>

Ok, I'm not completely happy with the sequence of this, but it works.

logical_ring_init() is the beast that initialises the intel_engine_cs,
and it looks dubious to be setting fields (like dev and scratch_obj)
before we do the main initialisation. I don't have a pretty solution
(thinking of passing around the scratch object, or reordering everything
still further with resulting code duplication for the other rings).

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index c9255fc..0d350f6 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -1223,6 +1223,12 @@  static int intel_init_workaround_bb(struct intel_engine_cs *ring)
 
 	WARN_ON(ring->id != RCS);
 
+	/* some WA perform writes to scratch page, ensure it is valid */
+	if (ring->scratch.obj == NULL) {
+		DRM_ERROR("scratch page not allocated for %s\n", ring->name);
+		return -EINVAL;
+	}
+
 	ret = lrc_setup_wa_ctx_obj(ring, PAGE_SIZE);
 	if (ret) {
 		DRM_DEBUG_DRIVER("Failed to setup context WA page: %d\n", ret);
@@ -1657,7 +1663,8 @@  static int logical_render_ring_init(struct drm_device *dev)
 	ring->emit_bb_start = gen8_emit_bb_start;
 
 	ring->dev = dev;
-	ret = logical_ring_init(dev, ring);
+
+	ret = intel_init_pipe_control(ring);
 	if (ret)
 		return ret;
 
@@ -1672,9 +1679,10 @@  static int logical_render_ring_init(struct drm_device *dev)
 			  ret);
 	}
 
-	ret = intel_init_pipe_control(ring);
-	if (ret)
+	ret = logical_ring_init(dev, ring);
+	if (ret) {
 		lrc_destroy_wa_ctx_obj(ring);
+	}
 
 	return ret;
 }