diff mbox

[02/18] drm/i915: Semaphore MBOX update generalization

Message ID 1352219142-1395-3-git-send-email-ben@bwidawsk.net (mailing list archive)
State New, archived
Headers show

Commit Message

Ben Widawsky Nov. 6, 2012, 4:25 p.m. UTC 
This replaces the existing MBOX update code with a more generalized
calculation for emitting mbox updates. We also create a sentinel for
doing the updates so we can more abstractly deal with the rings.

When doing MBOX updates the code must be aware of the /other/ rings.
Until now the platforms which supported semaphores had a fixed number of
rings and so it made sense for the code to be very specialized
(hardcoded).

The patch does contain a functional change, but should have no
behavioral changes.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_reg.h         |  1 +
 drivers/gpu/drm/i915/intel_ringbuffer.c | 40 ++++++++++++++++++++-------------
 drivers/gpu/drm/i915/intel_ringbuffer.h |  2 +-
 3 files changed, 27 insertions(+), 16 deletions(-)

Comments

Jani Nikula Nov. 7, 2012, 2 p.m. UTC | #1 
On Tue, 06 Nov 2012, Ben Widawsky <ben@bwidawsk.net> wrote:
> This replaces the existing MBOX update code with a more generalized
> calculation for emitting mbox updates. We also create a sentinel for
> doing the updates so we can more abstractly deal with the rings.
>
> When doing MBOX updates the code must be aware of the /other/ rings.
> Until now the platforms which supported semaphores had a fixed number of
> rings and so it made sense for the code to be very specialized
> (hardcoded).
>
> The patch does contain a functional change, but should have no
> behavioral changes.
>
> Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> ---
>  drivers/gpu/drm/i915/i915_reg.h         |  1 +
>  drivers/gpu/drm/i915/intel_ringbuffer.c | 40 ++++++++++++++++++++-------------
>  drivers/gpu/drm/i915/intel_ringbuffer.h |  2 +-
>  3 files changed, 27 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index f82755e..d220410 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -438,6 +438,7 @@
>  #define GEN6_VRSYNC (RING_SYNC_1(GEN6_BSD_RING_BASE))
>  #define GEN6_VBSYNC (RING_SYNC_0(GEN6_BSD_RING_BASE))
>  #define GEN6_BRSYNC (RING_SYNC_0(BLT_RING_BASE))
> +#define GEN6_NOSYNC 0
>  #define GEN6_BVSYNC (RING_SYNC_1(BLT_RING_BASE))
>  #define RING_MAX_IDLE(base)	((base)+0x54)
>  #define RING_HWS_PGA(base)	((base)+0x80)
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index 423948f..ace1176 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -558,12 +558,14 @@ update_mboxes(struct intel_ring_buffer *ring,
>  	    u32 seqno,
>  	    u32 mmio_offset)
>  {
> +#define MBOX_UPDATE_DWORDS 4
>  	intel_ring_emit(ring, MI_SEMAPHORE_MBOX |
>  			      MI_SEMAPHORE_GLOBAL_GTT |
>  			      MI_SEMAPHORE_REGISTER |
>  			      MI_SEMAPHORE_UPDATE);
>  	intel_ring_emit(ring, seqno);
>  	intel_ring_emit(ring, mmio_offset);
> +	intel_ring_emit(ring, MI_NOOP);

I take it this is the functional change you refer to in the commit
message, but the reason why is missing.

>  }
>  
>  /**
> @@ -579,21 +581,26 @@ static int
>  gen6_add_request(struct intel_ring_buffer *ring,
>  		 u32 *seqno)
>  {
> -	u32 mbox1_reg;
> -	u32 mbox2_reg;
> -	int ret;
> +	struct drm_device *dev = ring->dev;
> +	struct drm_i915_private *dev_priv = dev->dev_private;
> +	struct intel_ring_buffer *useless;
> +	int i, ret;
>  
> -	ret = intel_ring_begin(ring, 10);
> +	ret = intel_ring_begin(ring, ((I915_NUM_RINGS-1) *
> +				      MBOX_UPDATE_DWORDS) +
> +				      4);

My only (possibly unwarranted) worry about this patch is that this and
the for_each_ring below implicitly expect each ring->signal_mbox to have
*exactly* one GEN6_NOSYNC, and there are no comments or checks about
it. How does it blow up if that is not the case?

Other than the comments above,

Reviewed-by: Jani Nikula <jani.nikula@intel.com>

>  	if (ret)
>  		return ret;
> -
> -	mbox1_reg = ring->signal_mbox[0];
> -	mbox2_reg = ring->signal_mbox[1];
> +#undef MBOX_UPDATE_DWORDS
>  
>  	*seqno = i915_gem_next_request_seqno(ring);
>  
> -	update_mboxes(ring, *seqno, mbox1_reg);
> -	update_mboxes(ring, *seqno, mbox2_reg);
> +	for_each_ring(useless, dev_priv, i) {
> +		u32 mbox_reg = ring->signal_mbox[i];
> +		if (mbox_reg != GEN6_NOSYNC)
> +			update_mboxes(ring, *seqno, mbox_reg);
> +	}
> +
>  	intel_ring_emit(ring, MI_STORE_DWORD_INDEX);
>  	intel_ring_emit(ring, I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT);
>  	intel_ring_emit(ring, *seqno);
> @@ -1506,8 +1513,9 @@ int intel_init_render_ring_buffer(struct drm_device *dev)
>  		ring->semaphore_register[RCS] = MI_SEMAPHORE_SYNC_INVALID;
>  		ring->semaphore_register[VCS] = MI_SEMAPHORE_SYNC_RV;
>  		ring->semaphore_register[BCS] = MI_SEMAPHORE_SYNC_RB;
> -		ring->signal_mbox[0] = GEN6_VRSYNC;
> -		ring->signal_mbox[1] = GEN6_BRSYNC;
> +		ring->signal_mbox[RCS] = GEN6_NOSYNC;
> +		ring->signal_mbox[VCS] = GEN6_VRSYNC;
> +		ring->signal_mbox[BCS] = GEN6_BRSYNC;
>  	} else if (IS_GEN5(dev)) {
>  		ring->add_request = pc_render_add_request;
>  		ring->flush = gen4_render_ring_flush;
> @@ -1642,8 +1650,9 @@ int intel_init_bsd_ring_buffer(struct drm_device *dev)
>  		ring->semaphore_register[RCS] = MI_SEMAPHORE_SYNC_VR;
>  		ring->semaphore_register[VCS] = MI_SEMAPHORE_SYNC_INVALID;
>  		ring->semaphore_register[BCS] = MI_SEMAPHORE_SYNC_VB;
> -		ring->signal_mbox[0] = GEN6_RVSYNC;
> -		ring->signal_mbox[1] = GEN6_BVSYNC;
> +		ring->signal_mbox[RCS] = GEN6_RVSYNC;
> +		ring->signal_mbox[VCS] = GEN6_NOSYNC;
> +		ring->signal_mbox[BCS] = GEN6_BVSYNC;
>  	} else {
>  		ring->mmio_base = BSD_RING_BASE;
>  		ring->flush = bsd_ring_flush;
> @@ -1687,8 +1696,9 @@ int intel_init_blt_ring_buffer(struct drm_device *dev)
>  	ring->semaphore_register[RCS] = MI_SEMAPHORE_SYNC_BR;
>  	ring->semaphore_register[VCS] = MI_SEMAPHORE_SYNC_BV;
>  	ring->semaphore_register[BCS] = MI_SEMAPHORE_SYNC_INVALID;
> -	ring->signal_mbox[0] = GEN6_RBSYNC;
> -	ring->signal_mbox[1] = GEN6_VBSYNC;
> +	ring->signal_mbox[RCS] = GEN6_RBSYNC;
> +	ring->signal_mbox[VCS] = GEN6_VBSYNC;
> +	ring->signal_mbox[BCS] = GEN6_NOSYNC;
>  	ring->init = init_ring_common;
>  
>  	return intel_init_ring_buffer(dev, ring);
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
> index df1a0a2..d8eecb1 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.h
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
> @@ -90,7 +90,7 @@ struct  intel_ring_buffer {
>  				   u32 seqno);
>  
>  	u32		semaphore_register[I915_NUM_RINGS]; /*our mbox written by others */
> -	u32		signal_mbox[2]; /* mboxes this ring signals to */
> +	u32		signal_mbox[I915_NUM_RINGS]; /* mboxes this ring signals to */
>  	/**
>  	 * List of objects currently involved in rendering from the
>  	 * ringbuffer.
> -- 
> 1.8.0
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index f82755e..d220410 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -438,6 +438,7 @@ 
 #define GEN6_VRSYNC (RING_SYNC_1(GEN6_BSD_RING_BASE))
 #define GEN6_VBSYNC (RING_SYNC_0(GEN6_BSD_RING_BASE))
 #define GEN6_BRSYNC (RING_SYNC_0(BLT_RING_BASE))
+#define GEN6_NOSYNC 0
 #define GEN6_BVSYNC (RING_SYNC_1(BLT_RING_BASE))
 #define RING_MAX_IDLE(base)	((base)+0x54)
 #define RING_HWS_PGA(base)	((base)+0x80)
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 423948f..ace1176 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -558,12 +558,14 @@  update_mboxes(struct intel_ring_buffer *ring,
 	    u32 seqno,
 	    u32 mmio_offset)
 {
+#define MBOX_UPDATE_DWORDS 4
 	intel_ring_emit(ring, MI_SEMAPHORE_MBOX |
 			      MI_SEMAPHORE_GLOBAL_GTT |
 			      MI_SEMAPHORE_REGISTER |
 			      MI_SEMAPHORE_UPDATE);
 	intel_ring_emit(ring, seqno);
 	intel_ring_emit(ring, mmio_offset);
+	intel_ring_emit(ring, MI_NOOP);
 }
 
 /**
@@ -579,21 +581,26 @@  static int
 gen6_add_request(struct intel_ring_buffer *ring,
 		 u32 *seqno)
 {
-	u32 mbox1_reg;
-	u32 mbox2_reg;
-	int ret;
+	struct drm_device *dev = ring->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_ring_buffer *useless;
+	int i, ret;
 
-	ret = intel_ring_begin(ring, 10);
+	ret = intel_ring_begin(ring, ((I915_NUM_RINGS-1) *
+				      MBOX_UPDATE_DWORDS) +
+				      4);
 	if (ret)
 		return ret;
-
-	mbox1_reg = ring->signal_mbox[0];
-	mbox2_reg = ring->signal_mbox[1];
+#undef MBOX_UPDATE_DWORDS
 
 	*seqno = i915_gem_next_request_seqno(ring);
 
-	update_mboxes(ring, *seqno, mbox1_reg);
-	update_mboxes(ring, *seqno, mbox2_reg);
+	for_each_ring(useless, dev_priv, i) {
+		u32 mbox_reg = ring->signal_mbox[i];
+		if (mbox_reg != GEN6_NOSYNC)
+			update_mboxes(ring, *seqno, mbox_reg);
+	}
+
 	intel_ring_emit(ring, MI_STORE_DWORD_INDEX);
 	intel_ring_emit(ring, I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT);
 	intel_ring_emit(ring, *seqno);
@@ -1506,8 +1513,9 @@  int intel_init_render_ring_buffer(struct drm_device *dev)
 		ring->semaphore_register[RCS] = MI_SEMAPHORE_SYNC_INVALID;
 		ring->semaphore_register[VCS] = MI_SEMAPHORE_SYNC_RV;
 		ring->semaphore_register[BCS] = MI_SEMAPHORE_SYNC_RB;
-		ring->signal_mbox[0] = GEN6_VRSYNC;
-		ring->signal_mbox[1] = GEN6_BRSYNC;
+		ring->signal_mbox[RCS] = GEN6_NOSYNC;
+		ring->signal_mbox[VCS] = GEN6_VRSYNC;
+		ring->signal_mbox[BCS] = GEN6_BRSYNC;
 	} else if (IS_GEN5(dev)) {
 		ring->add_request = pc_render_add_request;
 		ring->flush = gen4_render_ring_flush;
@@ -1642,8 +1650,9 @@  int intel_init_bsd_ring_buffer(struct drm_device *dev)
 		ring->semaphore_register[RCS] = MI_SEMAPHORE_SYNC_VR;
 		ring->semaphore_register[VCS] = MI_SEMAPHORE_SYNC_INVALID;
 		ring->semaphore_register[BCS] = MI_SEMAPHORE_SYNC_VB;
-		ring->signal_mbox[0] = GEN6_RVSYNC;
-		ring->signal_mbox[1] = GEN6_BVSYNC;
+		ring->signal_mbox[RCS] = GEN6_RVSYNC;
+		ring->signal_mbox[VCS] = GEN6_NOSYNC;
+		ring->signal_mbox[BCS] = GEN6_BVSYNC;
 	} else {
 		ring->mmio_base = BSD_RING_BASE;
 		ring->flush = bsd_ring_flush;
@@ -1687,8 +1696,9 @@  int intel_init_blt_ring_buffer(struct drm_device *dev)
 	ring->semaphore_register[RCS] = MI_SEMAPHORE_SYNC_BR;
 	ring->semaphore_register[VCS] = MI_SEMAPHORE_SYNC_BV;
 	ring->semaphore_register[BCS] = MI_SEMAPHORE_SYNC_INVALID;
-	ring->signal_mbox[0] = GEN6_RBSYNC;
-	ring->signal_mbox[1] = GEN6_VBSYNC;
+	ring->signal_mbox[RCS] = GEN6_RBSYNC;
+	ring->signal_mbox[VCS] = GEN6_VBSYNC;
+	ring->signal_mbox[BCS] = GEN6_NOSYNC;
 	ring->init = init_ring_common;
 
 	return intel_init_ring_buffer(dev, ring);
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index df1a0a2..d8eecb1 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -90,7 +90,7 @@  struct  intel_ring_buffer {
 				   u32 seqno);
 
 	u32		semaphore_register[I915_NUM_RINGS]; /*our mbox written by others */
-	u32		signal_mbox[2]; /* mboxes this ring signals to */
+	u32		signal_mbox[I915_NUM_RINGS]; /* mboxes this ring signals to */
 	/**
 	 * List of objects currently involved in rendering from the
 	 * ringbuffer.