From: Jani Nikula <jani.nikula@linux.intel.com>
To: Uma Shankar <uma.shankar@intel.com>, intel-gfx@lists.freedesktop.org
Subject: Re: [Intel-gfx] [PATCH] drm/i915/display: Add a vblank wait for FBC activation within same frame
Date: Thu, 10 Sep 2020 16:33:53 +0300 [thread overview]
Message-ID: <878sdh21tq.fsf@intel.com> (raw)
In-Reply-To: <20200910121153.6749-1-uma.shankar@intel.com>
On Thu, 10 Sep 2020, Uma Shankar <uma.shankar@intel.com> wrote:
> Add a vblank wait when fbc activation request comes for the
> same frame on TGL. This helps fix underrun related to fbc.
>
> Signed-off-by: Uma Shankar <uma.shankar@intel.com>
> ---
> drivers/gpu/drm/i915/display/intel_fbc.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> index 135f5e8a4d70..3e1d715e4a4e 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> @@ -1055,6 +1055,7 @@ static void __intel_fbc_post_update(struct intel_crtc *crtc)
> {
> struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> struct intel_fbc *fbc = &dev_priv->fbc;
> + static u32 old_frame_cnt, new_frame_cnt;
In the strongest terms, do not add static data. These would be shared
across devices, which is certainly a bug.
BR,
Jani.
>
> drm_WARN_ON(&dev_priv->drm, !mutex_is_locked(&fbc->lock));
>
> @@ -1075,10 +1076,18 @@ static void __intel_fbc_post_update(struct intel_crtc *crtc)
> if (!intel_fbc_can_activate(crtc))
> return;
>
> - if (!fbc->busy_bits)
> + old_frame_cnt = new_frame_cnt;
> + new_frame_cnt = intel_crtc_get_vblank_counter(crtc);
> + if (!fbc->busy_bits) {
> + if (IS_TIGERLAKE(dev_priv) &&
> + old_frame_cnt == new_frame_cnt) {
> + drm_dbg_kms(&dev_priv->drm, "Wait for vblank before Activating FBC");
> + intel_wait_for_vblank_if_active(dev_priv, crtc->pipe);
> + }
> intel_fbc_hw_activate(dev_priv);
> - else
> + } else {
> intel_fbc_deactivate(dev_priv, "frontbuffer write");
> + }
> }
>
> void intel_fbc_post_update(struct intel_atomic_state *state,
--
Jani Nikula, Intel Open Source Graphics Center
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
next prev parent reply other threads:[~2020-09-10 13:33 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-10 12:11 [Intel-gfx] [PATCH] drm/i915/display: Add a vblank wait for FBC activation within same frame Uma Shankar
2020-09-10 13:28 ` [Intel-gfx] ✓ Fi.CI.BAT: success for " Patchwork
2020-09-10 13:33 ` Jani Nikula [this message]
2020-09-10 13:42 ` [Intel-gfx] [PATCH] " Shankar, Uma
2020-09-10 13:52 ` Ville Syrjälä
2020-09-10 13:59 ` Shankar, Uma
2020-09-10 15:31 ` [Intel-gfx] ✗ Fi.CI.IGT: failure for " Patchwork
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=878sdh21tq.fsf@intel.com \
--to=jani.nikula@linux.intel.com \
--cc=intel-gfx@lists.freedesktop.org \
--cc=uma.shankar@intel.com \
/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.