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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 7BF36FE51FF for ; Fri, 24 Apr 2026 10:19:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=lrLpElpQfj3uy5+voJ0Sluen68qgiUnjoK6buk2WaM8=; b=SdSxz3oFDb2MbeWg3H/gZCNOl+ VE2DlxawlnyOK/GRDabGN2F+d8bPGNELMV8avXHIXs7qgFF0tFFwWtSbGi+Rb8XkP+f97UdJBMHKs LKy3pZ006XJxPCzyov6/NGqQNlBY30KCofRsiVqEoFibB+gu486IMnI9+m6JdiiWBAZ7isPcxbgUj XfD4VreLL9AZQtDDdRt+OkH6YVPDP8MePB/hl4cquBNEuOblLvfZrLyK1wWRkPg8B4uNNtSFTmBAn UN78c0g4KNzc5YOGeiPuVNriasCBfjsv+J7j+muYj6X0Ec2kuXoD5h0ziDcz29rzvHYsUT4czFzFI RAObOF/Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wGDdP-0000000D0yC-22vm; Fri, 24 Apr 2026 10:19:43 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wGDdH-0000000D0oQ-2yIb for linux-arm-kernel@lists.infradead.org; Fri, 24 Apr 2026 10:19:37 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 19BF044709; Fri, 24 Apr 2026 10:19:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 658CEC2BCF7; Fri, 24 Apr 2026 10:19:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777025974; bh=ADrjMl7mpDtwIFQps9vB928G+b6i67xO6MVoZtVVknc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=ZZ5QKNetkN/X5ZxdvMG2nnWbXdIB4LS2VJo4FixXx9lAukRoQy1FeWH85SHS9v3LB 9ZhDsw0eimOgz6qVs91Comnxd5s3hTah0fwKt2wlZf0VjXTmtBRbOWJa1AdOq/orx2 9Y9VpSQ7SphCtzMgJimeJPKZsT3w9Gw0le2MESJqm26DJkJmXZ+nlkF9RE7mrcVqcq zwcJeUukDFHg0ixPZbrzimLUUe3+B6BZhhis/N5dYDd/MJxrpcgE6EJejYSs2yISdu AoV1lUq2LD/ailu1wHXTS/gDz4dWWjTV9x9C5gn3Ua31h6q3cfGXk6XtvhX8OR5fjm iRPBAFAMI8vwA== From: Maxime Ripard Date: Fri, 24 Apr 2026 12:18:52 +0200 Subject: [PATCH v3 12/20] drm/crtc: Add new atomic_create_state callback MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260424-drm-mode-config-init-v3-12-8b68d9db0d8b@kernel.org> References: <20260424-drm-mode-config-init-v3-0-8b68d9db0d8b@kernel.org> In-Reply-To: <20260424-drm-mode-config-init-v3-0-8b68d9db0d8b@kernel.org> To: Maarten Lankhorst , Thomas Zimmermann , David Airlie , Simona Vetter , Jonathan Corbet , Shuah Khan , Dmitry Baryshkov , Jyri Sarha , Tomi Valkeinen , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Simon Ser , Harry Wentland , Melissa Wen , Sebastian Wick , Alex Hung , Jani Nikula , Rodrigo Vivi , Joonas Lahtinen , Tvrtko Ursulin , Chen-Yu Tsai , Samuel Holland , Dave Stevenson , =?utf-8?q?Ma=C3=ADra_Canal?= , Raspberry Pi Kernel Maintenance Cc: dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Daniel Stone , intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev, Maxime Ripard X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=7554; i=mripard@kernel.org; h=from:subject:message-id; bh=ADrjMl7mpDtwIFQps9vB928G+b6i67xO6MVoZtVVknc=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDJmvnXtdlJsub7zl3tot7Xxqyvv03ztvyWQs8PR6WVvMX mA2ZerEjqksDMKcDLJiiixPZMJOL29fXOVgv/IHzBxWJpAhDFycAjCRm5WM9f5/v3gcKQnyYP7w /KTQ89pj9p3Sk2wSe0PjeWU67HZ81Dt8/Neiaxn+MywnzF9Wrb5uF2ND99wJr6fz7PhoMJ+R82/ UZYeVd5h/9yqZXLL+f/p+bNakhftlq2YG1D675SZ8PCtvgYUaAA== X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260424_031935_835761_171C1DF9 X-CRM114-Status: GOOD ( 23.30 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Commit 47b5ac7daa46 ("drm/atomic: Add new atomic_create_state callback to drm_private_obj") introduced a new pattern for allocating drm object states. Instead of relying on the reset() callback, it created a new atomic_create_state hook. This is helpful because reset is a bit overloaded: it's used to create the initial software state, reset it, but also reset the hardware. It can also be used either at probe time, to create the initial state and possibly reset the hardware to an expected default, but also during suspend/resume. Both these cases come with different expectations too: during the initialization, we want to initialize all states, but during suspend/resume, drm_private_states for example are expected to be kept around. reset() also isn't fallible, which makes it harder to handle initialization errors properly. This is only really relevant for some drivers though, since all the helpers for reset only create a new state, and don't touch the hardware at all. It was thus decided to create a new hook that would allocate and initialize a pristine state without any side effect: atomic_create_state to untangle a bit some of it, and to separate the initialization with the actual reset one might need during a suspend/resume. Continue the transition to the new pattern with CRTCs. Reviewed-by: Dmitry Baryshkov Signed-off-by: Maxime Ripard --- drivers/gpu/drm/drm_atomic_state_helper.c | 47 +++++++++++++++++++++++++++++++ drivers/gpu/drm/drm_mode_config.c | 21 +++++++++++++- include/drm/drm_atomic_state_helper.h | 4 +++ include/drm/drm_crtc.h | 16 +++++++++++ 4 files changed, 87 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c index 9cd8550cabb7..b7da134c8c50 100644 --- a/drivers/gpu/drm/drm_atomic_state_helper.c +++ b/drivers/gpu/drm/drm_atomic_state_helper.c @@ -103,10 +103,32 @@ __drm_atomic_helper_crtc_reset(struct drm_crtc *crtc, crtc->state = crtc_state; } EXPORT_SYMBOL(__drm_atomic_helper_crtc_reset); +/** + * __drm_atomic_helper_crtc_create_state - initializes crtc state + * @crtc: crtc object + * @state: new state to initialize + * + * Initializes the newly allocated @state, usually required when + * initializing the drivers. + * + * @state is assumed to be zeroed. + * + * This is useful for drivers that subclass @drm_crtc_state. + */ +void __drm_atomic_helper_crtc_create_state(struct drm_crtc *crtc, + struct drm_crtc_state *state) +{ + __drm_atomic_helper_crtc_state_init(state, crtc); + + if (drm_dev_has_vblank(crtc->dev)) + drm_crtc_vblank_reset(crtc); +} +EXPORT_SYMBOL(__drm_atomic_helper_crtc_create_state); + /** * drm_atomic_helper_crtc_reset - default &drm_crtc_funcs.reset hook for CRTCs * @crtc: drm CRTC * * Resets the atomic state for @crtc by freeing the state pointer (which might @@ -122,10 +144,35 @@ void drm_atomic_helper_crtc_reset(struct drm_crtc *crtc) __drm_atomic_helper_crtc_reset(crtc, crtc_state); } EXPORT_SYMBOL(drm_atomic_helper_crtc_reset); +/** + * drm_atomic_helper_crtc_create_state - default &drm_crtc_funcs.atomic_create_state hook for crtcs + * @crtc: crtc object + * + * Initializes a pristine @drm_crtc_state. + * + * This is useful for drivers that don't subclass @drm_crtc_state. + * + * RETURNS: + * Pointer to new crtc state, or ERR_PTR on failure. + */ +struct drm_crtc_state *drm_atomic_helper_crtc_create_state(struct drm_crtc *crtc) +{ + struct drm_crtc_state *state; + + state = kzalloc_obj(*state); + if (!state) + return ERR_PTR(-ENOMEM); + + __drm_atomic_helper_crtc_create_state(crtc, state); + + return state; +} +EXPORT_SYMBOL(drm_atomic_helper_crtc_create_state); + /** * __drm_atomic_helper_crtc_duplicate_state - copy atomic CRTC state * @crtc: CRTC object * @state: atomic CRTC state * diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c index 10b7815cbe48..182d9a8104e7 100644 --- a/drivers/gpu/drm/drm_mode_config.c +++ b/drivers/gpu/drm/drm_mode_config.c @@ -196,10 +196,26 @@ static int drm_mode_config_plane_create_state(struct drm_plane *plane) plane->state = plane_state; return 0; } +static int drm_mode_config_crtc_create_state(struct drm_crtc *crtc) +{ + struct drm_crtc_state *crtc_state; + + if (!crtc->funcs->atomic_create_state) + return 0; + + crtc_state = crtc->funcs->atomic_create_state(crtc); + if (IS_ERR(crtc_state)) + return PTR_ERR(crtc_state); + + crtc->state = crtc_state; + + return 0; +} + /** * drm_mode_config_reset - call ->reset callbacks * @dev: drm device * * This functions calls all the crtc's, encoder's and connector's ->reset @@ -227,13 +243,16 @@ void drm_mode_config_reset(struct drm_device *dev) plane->funcs->reset(plane); else if (plane->funcs->atomic_create_state) drm_mode_config_plane_create_state(plane); } - drm_for_each_crtc(crtc, dev) + drm_for_each_crtc(crtc, dev) { if (crtc->funcs->reset) crtc->funcs->reset(crtc); + else if (crtc->funcs->atomic_create_state) + drm_mode_config_crtc_create_state(crtc); + } drm_for_each_encoder(encoder, dev) if (encoder->funcs && encoder->funcs->reset) encoder->funcs->reset(encoder); diff --git a/include/drm/drm_atomic_state_helper.h b/include/drm/drm_atomic_state_helper.h index e7fbbfdc5d69..129762b99de6 100644 --- a/include/drm/drm_atomic_state_helper.h +++ b/include/drm/drm_atomic_state_helper.h @@ -43,10 +43,14 @@ struct drm_device; void __drm_atomic_helper_crtc_state_init(struct drm_crtc_state *state, struct drm_crtc *crtc); void __drm_atomic_helper_crtc_reset(struct drm_crtc *crtc, struct drm_crtc_state *state); void drm_atomic_helper_crtc_reset(struct drm_crtc *crtc); +void __drm_atomic_helper_crtc_create_state(struct drm_crtc *crtc, + struct drm_crtc_state *state); +struct drm_crtc_state * +drm_atomic_helper_crtc_create_state(struct drm_crtc *crtc); void __drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc, struct drm_crtc_state *state); struct drm_crtc_state * drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc); void __drm_atomic_helper_crtc_destroy_state(struct drm_crtc_state *state); diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 312fc1e745d2..41ea6eadf36f 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -636,10 +636,26 @@ struct drm_crtc_funcs { * 0 on success or a negative error code on failure. */ int (*set_property)(struct drm_crtc *crtc, struct drm_property *property, uint64_t val); + /** + * @atomic_create_state: + * + * Allocates a pristine, initialized, state for the CRTC object + * and returns it. This callback must have no side effects: in + * particular, the returned state must not be assigned to the + * object's state pointer and it must not affect the hardware + * state. + * + * RETURNS: + * + * A new, pristine, CRTC state instance or an error pointer + * on failure. + */ + struct drm_crtc_state *(*atomic_create_state)(struct drm_crtc *crtc); + /** * @atomic_duplicate_state: * * Duplicate the current atomic state for this CRTC and return it. * The core and helpers guarantee that any atomic state duplicated with -- 2.53.0