AMD-GFX Archive on lore.kernel.org
 help / color / Atom feed
From: "Li, Roman" <Roman.Li@amd.com>
To: "Kazlauskas, Nicholas" <Nicholas.Kazlauskas@amd.com>,
	"amd-gfx@lists.freedesktop.org" <amd-gfx@lists.freedesktop.org>
Cc: "Wu, Hersen" <hersenxs.wu@amd.com>,
	"Siqueira, Rodrigo" <Rodrigo.Siqueira@amd.com>,
	"Lakha, Bhawanpreet" <Bhawanpreet.Lakha@amd.com>,
	"Kazlauskas,  Nicholas" <Nicholas.Kazlauskas@amd.com>
Subject: RE: [PATCH] drm/amd/display: Only revalidate bandwidth on medium and fast updates
Date: Tue, 30 Jun 2020 15:26:35 +0000
Message-ID: <BN7PR12MB280144B4E496EDE39FBD3E19896F0@BN7PR12MB2801.namprd12.prod.outlook.com> (raw)
In-Reply-To: <20200629204924.13426-1-nicholas.kazlauskas@amd.com>

[AMD Public Use]

Reviewed-by: Roman Li <Roman.Li@amd.com>

-----Original Message-----
From: amd-gfx <amd-gfx-bounces@lists.freedesktop.org> On Behalf Of Nicholas Kazlauskas
Sent: Monday, June 29, 2020 4:49 PM
To: amd-gfx@lists.freedesktop.org
Cc: Lakha, Bhawanpreet <Bhawanpreet.Lakha@amd.com>; Siqueira, Rodrigo <Rodrigo.Siqueira@amd.com>; Wu, Hersen <hersenxs.wu@amd.com>; Kazlauskas, Nicholas <Nicholas.Kazlauskas@amd.com>
Subject: [PATCH] drm/amd/display: Only revalidate bandwidth on medium and fast updates

[Why]
Changes that are fast don't require updating DLG parameters making this call unnecessary. Considering this is an expensive call it should not be done on every flip.

DML touches clocks, p-state support, DLG params and a few other DC internal flags and these aren't expected during fast. A hang has been reported with this change when called on every flip which suggests that modifying these fields is not recommended behavior on fast updates.

[How]
Guard the validation to only happen if update type isn't FAST.

Bug: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitlab.freedesktop.org%2Fdrm%2Famd%2F-%2Fissues%2F1191&amp;data=02%7C01%7Croman.li%40amd.com%7Cc98c2d3c363643a4fef208d81c6dfa68%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637290606647861029&amp;sdata=%2B3rZlvLgef1c2FOYTKx37U%2Fbr%2BWOxI9GXVI2K7HjH3E%3D&amp;reserved=0
Fixes: e1995f0909e3 ("drm/amd/display: Revalidate bandwidth before commiting DC updates")
Cc: Hersen Wu <hersenxs.wu@amd.com>
Cc: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index 67402d75e67e..942ceb0f6383 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -2607,10 +2607,12 @@ void dc_commit_updates_for_stream(struct dc *dc,
 
 	copy_stream_update_to_stream(dc, context, stream, stream_update);
 
-	if (!dc->res_pool->funcs->validate_bandwidth(dc, context, false)) {
-		DC_ERROR("Mode validation failed for stream update!\n");
-		dc_release_state(context);
-		return;
+	if (update_type > UPDATE_TYPE_FAST) {
+		if (!dc->res_pool->funcs->validate_bandwidth(dc, context, false)) {
+			DC_ERROR("Mode validation failed for stream update!\n");
+			dc_release_state(context);
+			return;
+		}
 	}
 
 	commit_planes_for_stream(
--
2.25.1

_______________________________________________
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Famd-gfx&amp;data=02%7C01%7Croman.li%40amd.com%7Cc98c2d3c363643a4fef208d81c6dfa68%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637290606647861029&amp;sdata=EPY6DwDOG88a944QieZj%2F8NSeBJTot2z1WLghTM2Iuw%3D&amp;reserved=0
_______________________________________________
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx

      parent reply index

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-29 20:49 Nicholas Kazlauskas
2020-06-29 21:58 ` Alex Deucher
2020-06-30 15:26 ` Li, Roman [this message]

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=BN7PR12MB280144B4E496EDE39FBD3E19896F0@BN7PR12MB2801.namprd12.prod.outlook.com \
    --to=roman.li@amd.com \
    --cc=Bhawanpreet.Lakha@amd.com \
    --cc=Nicholas.Kazlauskas@amd.com \
    --cc=Rodrigo.Siqueira@amd.com \
    --cc=amd-gfx@lists.freedesktop.org \
    --cc=hersenxs.wu@amd.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

AMD-GFX Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/amd-gfx/0 amd-gfx/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 amd-gfx amd-gfx/ https://lore.kernel.org/amd-gfx \
		amd-gfx@lists.freedesktop.org
	public-inbox-index amd-gfx

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.freedesktop.lists.amd-gfx


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git