From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BE9A8C54795 for ; Mon, 19 May 2025 21:21:56 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BBF8510E3F2; Mon, 19 May 2025 21:21:54 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="WFn9euy1"; dkim-atps=neutral Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by gabe.freedesktop.org (Postfix) with ESMTPS id 035E610E3E9; Mon, 19 May 2025 21:21:52 +0000 (UTC) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id A86C05C05CD; Mon, 19 May 2025 21:19:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D127DC4CEE4; Mon, 19 May 2025 21:21:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1747689707; bh=H23H+mpcL8SHm2I4A3L8pf8bltvgAwtxp/DyOc76IU4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WFn9euy1Xux7tU6/4R2PJ3V0uR7Bq1eGZXthwOd1hwAM9PTtMdSLE9yb5uS9loWRP rmEikdPc/ZpwZx1LPTPbX6PJT5sRvjx3wn6WR2x837JmYzMGmEG+aFyg/JS6vIt2G6 4kxwU2XeWGyOAVEHC+MwwOrZwvrQBt4lli3shCbPKRNtkZL/BOrBobnSANsysU/7m3 fJOKEP0vpSlqAovN3EVj3/UB92rtpoIGKwATGvcAYXilQpzm5CJ+Ati5VF0NKoMreR Oki+obGN8Wq7qQx30iPnb7aQ58HJGUJAUp3BewAqYKpKsz47pCO4zSZ1zivdCBzkA1 nyFhJSvUrhy8Q== From: Sasha Levin To: patches@lists.linux.dev, stable@vger.kernel.org Cc: George Shen , Wenjing Liu , Ray Wu , Daniel Wheeler , Alex Deucher , Sasha Levin , harry.wentland@amd.com, sunpeng.li@amd.com, christian.koenig@amd.com, David1.Zhou@amd.com, airlied@linux.ie, daniel@ffwll.ch, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH AUTOSEL 6.14 10/23] drm/amd/display: fix link_set_dpms_off multi-display MST corner case Date: Mon, 19 May 2025 17:21:17 -0400 Message-Id: <20250519212131.1985647-10-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250519212131.1985647-1-sashal@kernel.org> References: <20250519212131.1985647-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.14.7 Content-Transfer-Encoding: 8bit X-BeenThere: amd-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussion list for AMD gfx List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: amd-gfx-bounces@lists.freedesktop.org Sender: "amd-gfx" From: George Shen [ Upstream commit 3c1a467372e0c356b1d3c59f6d199ed5a6612dd1 ] [Why & How] When MST config is unplugged/replugged too quickly, it can potentially result in a scenario where previous DC state has not been reset before the HPD link detection sequence begins. In this case, driver will disable the streams/link prior to re-enabling the link for link training. There is a bug in the current logic that does not account for the fact that current_state can be released and cleared prior to swapping to a new state (resulting in the pipe_ctx stream pointers to be cleared) in between disabling streams. To resolve this, cache the original streams prior to committing any stream updates. Reviewed-by: Wenjing Liu Signed-off-by: George Shen Signed-off-by: Ray Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 1561782686ccc36af844d55d31b44c938dd412dc) Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/display/dc/link/link_dpms.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/link/link_dpms.c b/drivers/gpu/drm/amd/display/dc/link/link_dpms.c index ec7de9c01fab0..e95ec72b4096c 100644 --- a/drivers/gpu/drm/amd/display/dc/link/link_dpms.c +++ b/drivers/gpu/drm/amd/display/dc/link/link_dpms.c @@ -148,6 +148,7 @@ void link_blank_dp_stream(struct dc_link *link, bool hw_init) void link_set_all_streams_dpms_off_for_link(struct dc_link *link) { struct pipe_ctx *pipes[MAX_PIPES]; + struct dc_stream_state *streams[MAX_PIPES]; struct dc_state *state = link->dc->current_state; uint8_t count; int i; @@ -160,10 +161,18 @@ void link_set_all_streams_dpms_off_for_link(struct dc_link *link) link_get_master_pipes_with_dpms_on(link, state, &count, pipes); + /* The subsequent call to dc_commit_updates_for_stream for a full update + * will release the current state and swap to a new state. Releasing the + * current state results in the stream pointers in the pipe_ctx structs + * to be zero'd. Hence, cache all streams prior to dc_commit_updates_for_stream. + */ + for (i = 0; i < count; i++) + streams[i] = pipes[i]->stream; + for (i = 0; i < count; i++) { - stream_update.stream = pipes[i]->stream; + stream_update.stream = streams[i]; dc_commit_updates_for_stream(link->ctx->dc, NULL, 0, - pipes[i]->stream, &stream_update, + streams[i], &stream_update, state); } -- 2.39.5