From patchwork Fri Jul 28 09:06:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Maxime Ripard X-Patchwork-Id: 13331518 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 8556AC001E0 for ; Fri, 28 Jul 2023 09:07:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E172A10E6B3; Fri, 28 Jul 2023 09:07:01 +0000 (UTC) Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2F4C410E6B0 for ; Fri, 28 Jul 2023 09:06:55 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A39F262080; Fri, 28 Jul 2023 09:06:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B09DBC433C7; Fri, 28 Jul 2023 09:06:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690535214; bh=gKdr5wVwnd5iV/T89XpwfyfOVoDtad9S9jijN97ZC8k=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=NvZe7XxAeMFcwVssgJ6Po1uWqAX+sCgVKij7qFhyIci/SGs3vgp2Q/BBOKi3Z0ZPe NkgrnodZv5N0SBw8D7CAAzyPAHPP88HjYKeXBFavyf7p73bCBtOf7E7Ug9hvCB03DR 09ogUjHXuauDqtkIDqVxy3o1vkhX+Fg8BWAlawzxbByn4BspGM3VeceaBf+JFmfJD6 bQBmClPX88tkzD98Qw6jWrzTlQXV2p+N6NwnFujlwsliJGQ5Nb6pYzZymcIBR9ZPqx RB5trmT8o6wLu9h21Dx8XOp14gwDK0ZZx7EKbgu6NIzJXpkCrJVoeVAhGuhxsrbvLc qIBALymEZ1nsw== From: Maxime Ripard Date: Fri, 28 Jul 2023 11:06:24 +0200 Subject: [PATCH v3 11/11] drm/vc4: tests: pv-muxing: Document test scenario MIME-Version: 1.0 Message-Id: <20230728-kms-kunit-actions-rework-v3-11-952565ccccfe@kernel.org> References: <20230728-kms-kunit-actions-rework-v3-0-952565ccccfe@kernel.org> In-Reply-To: <20230728-kms-kunit-actions-rework-v3-0-952565ccccfe@kernel.org> To: David Airlie , Daniel Vetter , Maarten Lankhorst , Thomas Zimmermann , Emma Anholt X-Mailer: b4 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=2113; i=mripard@kernel.org; h=from:subject:message-id; bh=gKdr5wVwnd5iV/T89XpwfyfOVoDtad9S9jijN97ZC8k=; b=owGbwMvMwCX2+D1vfrpE4FHG02pJDCmHW7k4XCezyX63vvt+s8yL0lWbVvzor5xkd3rR+y22+ b9YIk3tO0pZGMS4GGTFFFlihM2XxJ2a9bqTjW8ezBxWJpAhDFycAjCRVV4M/xMMTAy0V6zyXh2u lv1N3fX8svR6Ye164d+s73TV2FW3vWBkOBb/NFzo31S1xf+vlFx9EODwu2Zio2P+vlalVS9OTPo qzAQA X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kselftest@vger.kernel.org, Brendan Higgins , Javier Martinez Canillas , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, =?utf-8?q?Ma?= =?utf-8?q?=C3=ADra_Canal?= , Maxime Ripard , David Gow , kunit-dev@googlegroups.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" We've had a couple of tests that weren't really obvious, nor did they document what they were supposed to test. Document that to make it hopefully more obvious. Reviewed-by: Javier Martinez Canillas Reviewed-by: Maíra Canal Signed-off-by: Maxime Ripard --- drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c b/drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c index 5f9f5626329d..61622e951031 100644 --- a/drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c +++ b/drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c @@ -845,6 +845,13 @@ static void drm_test_vc5_pv_muxing_bugs_subsequent_crtc_enable(struct kunit *tes KUNIT_EXPECT_NE(test, hdmi0_channel, hdmi1_channel); } +/* + * This test makes sure that we never change the FIFO of an active HVS + * channel if we disable a FIFO with a lower index. + * + * Doing so would result in a FIFO stall and would disrupt an output + * supposed to be unaffected by the commit. + */ static void drm_test_vc5_pv_muxing_bugs_stable_fifo(struct kunit *test) { struct drm_modeset_acquire_ctx *ctx; @@ -924,6 +931,21 @@ static void drm_test_vc5_pv_muxing_bugs_stable_fifo(struct kunit *test) } } +/* + * Test that if we affect a single output, only the CRTC state of that + * output will be pulled in the global atomic state. + * + * This is relevant for two things: + * + * - If we don't have that state at all, we are unlikely to affect the + * FIFO muxing. This is somewhat redundant with + * drm_test_vc5_pv_muxing_bugs_stable_fifo() + * + * - KMS waits for page flips to occur on all the CRTC found in the + * CRTC state. Since the CRTC is unaffected, we would over-wait, but + * most importantly run into corner cases like waiting on an + * inactive CRTC that never completes. + */ static void drm_test_vc5_pv_muxing_bugs_subsequent_crtc_enable_too_many_crtc_state(struct kunit *test) {