All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jani Nikula <jani.nikula@linux.intel.com>
To: intel-gfx@lists.freedesktop.org
Cc: Ben Widawsky <ben@bwidawsk.net>
Subject: Re: [PATCH 02/18] drm/i915: Semaphore MBOX update generalization
Date: Wed, 07 Nov 2012 16:00:49 +0200	[thread overview]
Message-ID: <87vcdhldgu.fsf@intel.com> (raw)
In-Reply-To: <1352219142-1395-3-git-send-email-ben@bwidawsk.net>

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

  reply	other threads:[~2012-11-07 13:55 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-11-06 16:25 [PATCH 00/18] [RFC] Introduce the Haswell VECS Ben Widawsky
2012-11-06 16:25 ` [PATCH 01/18] drm/i915: Comments for semaphore clarification Ben Widawsky
2012-11-07 13:30   ` Jani Nikula
2012-11-06 16:25 ` [PATCH 02/18] drm/i915: Semaphore MBOX update generalization Ben Widawsky
2012-11-07 14:00   ` Jani Nikula [this message]
2012-11-06 16:25 ` [PATCH 03/18] drm/i915: Introduce VECS: the 4th ring Ben Widawsky
2012-11-06 16:25 ` [PATCH 04/18] drm/i915: Add VECS semaphore bits Ben Widawsky
2012-11-06 16:25 ` [PATCH 05/18] drm/i915: Rename ring flush functions Ben Widawsky
2012-11-07 14:47   ` Jani Nikula
2012-11-06 16:25 ` [PATCH 06/18] drm/i915: add HAS_VEBOX Ben Widawsky
2012-11-07 14:59   ` Jani Nikula
2012-11-06 16:25 ` [PATCH 07/18] drm/i915: Vebox ringbuffer init Ben Widawsky
2012-11-06 16:25 ` [PATCH 08/18] drm/i915: Create a more generic pm handler for hsw+ Ben Widawsky
2012-11-06 16:25 ` [PATCH 09/18] drm/i915: make PM interrupt writes non-destructive Ben Widawsky
2012-11-07 10:17   ` Chris Wilson
2012-11-07 11:53     ` Ben Widawsky
2012-11-12 19:11   ` [PATCH 09/18 v3] " Ben Widawsky
2012-11-12 19:39     ` [PATCH 09/18 v4] " Ben Widawsky
2012-11-06 16:25 ` [PATCH 10/18] drm/i915: Create an ivybridge_irq_preinstall Ben Widawsky
2012-11-06 16:25 ` [PATCH 11/18] drm/i915: Add PM regs to pre install Ben Widawsky
2012-11-06 16:25 ` [PATCH 12/18] drm/i915: Convert irq_refounct to struct Ben Widawsky
2012-11-06 16:25 ` [PATCH 13/18] drm/i915: consolidate interrupt naming scheme Ben Widawsky
2012-11-06 16:25 ` [PATCH 14/18] drm/i915: vebox interrupt get/put Ben Widawsky
2013-02-13 19:28   ` Daniel Vetter
2012-11-06 16:25 ` [PATCH 15/18] drm/i915: Enable vebox interrupts Ben Widawsky
2012-11-06 16:25 ` [PATCH 16/18] drm/i915: add VEBOX into debugfs Ben Widawsky
2012-11-06 16:25 ` [PATCH 17/18] drm/i915: add I915_EXEC_VEBOX to i915_gem_do_execbuffer() Ben Widawsky
2012-11-06 16:25 ` [PATCH 18/18] drm/i915: add I915_PARAM_HAS_VEBOX to i915_getparam Ben Widawsky
2012-11-07 12:03 ` [PATCH 00/18] [RFC] Introduce the Haswell VECS Ben Widawsky
  -- strict thread matches above, loose matches on Subject: below --
2013-04-28  0:59 [PATCH 00/18] " Ben Widawsky
2013-04-28  0:59 ` [PATCH 02/18] drm/i915: Semaphore MBOX update generalization Ben Widawsky
2013-05-07 15:34   ` Damien Lespiau
2013-05-08  5:17     ` Ben Widawsky
2013-05-29  2:22 ` [PATCH 00/18] Introduce the Haswell VECS v2 Ben Widawsky
2013-05-29  2:22   ` [PATCH 02/18] drm/i915: Semaphore MBOX update generalization Ben Widawsky
2013-05-29 16:05     ` Damien Lespiau

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87vcdhldgu.fsf@intel.com \
    --to=jani.nikula@linux.intel.com \
    --cc=ben@bwidawsk.net \
    --cc=intel-gfx@lists.freedesktop.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.