From patchwork Wed Mar 5 22:59:36 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lyude Paul X-Patchwork-Id: 14003648 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 D78D3C282EC for ; Wed, 5 Mar 2025 23:07:54 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 17D0E10E858; Wed, 5 Mar 2025 23:07:54 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="NQJBGNbc"; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id CF10B10E85A for ; Wed, 5 Mar 2025 23:07:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1741216072; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3Sa15p0zk9/0E89lqNYU9Y3htAIogxJ6GNdp/TIXh9E=; b=NQJBGNbc73lSIyX37/g2VGF00ucTURTVWRRUkj4tiVot30r7Fz3X3WeTbjMMM9XkQVqv6C jP620sto5tzwFt9QdrSNuFZta88rMcQUHmM+OjhMI5LUxQUTMMeouxoLQNTiOZXM+LwhE/ eVXi+CQZtR89gk3mEDK5qqw9bYxkm4M= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-590-gMt0t3KrPU-Esgh-380sOA-1; Wed, 05 Mar 2025 18:07:36 -0500 X-MC-Unique: gMt0t3KrPU-Esgh-380sOA-1 X-Mimecast-MFC-AGG-ID: gMt0t3KrPU-Esgh-380sOA_1741216054 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E452E18001D0; Wed, 5 Mar 2025 23:07:33 +0000 (UTC) Received: from chopper.redhat.com (unknown [10.22.88.81]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 802F5300019E; Wed, 5 Mar 2025 23:07:30 +0000 (UTC) From: Lyude Paul To: dri-devel@lists.freedesktop.org, rust-for-linux@vger.kernel.org Cc: Danilo Krummrich , mcanal@igalia.com, Alice Ryhl , Maxime Ripard , Simona Vetter , Daniel Almeida , Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , =?utf-8?q?B?= =?utf-8?q?j=C3=B6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Trevor Gross , linux-kernel@vger.kernel.org (open list) Subject: [RFC v3 20/33] rust: drm/kms: Add DriverPlane::atomic_update() Date: Wed, 5 Mar 2025 17:59:36 -0500 Message-ID: <20250305230406.567126-21-lyude@redhat.com> In-Reply-To: <20250305230406.567126-1-lyude@redhat.com> References: <20250305230406.567126-1-lyude@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" A mandatory trait method used for implementing DRM's atomic plane update callback. Signed-off-by: Lyude Paul --- rust/kernel/drm/kms/plane.rs | 45 +++++++++++++++++++++++++++++++++++- 1 file changed, 44 insertions(+), 1 deletion(-) diff --git a/rust/kernel/drm/kms/plane.rs b/rust/kernel/drm/kms/plane.rs index 4e73c2966ca22..b090aebc35649 100644 --- a/rust/kernel/drm/kms/plane.rs +++ b/rust/kernel/drm/kms/plane.rs @@ -70,7 +70,11 @@ pub trait DriverPlane: Send + Sync + Sized { begin_fb_access: None, end_fb_access: None, atomic_check: None, - atomic_update: None, + atomic_update: if Self::HAS_ATOMIC_UPDATE { + Some(atomic_update_callback::) + } else { + None + }, atomic_enable: None, atomic_disable: None, atomic_async_check: None, @@ -98,6 +102,21 @@ pub trait DriverPlane: Send + Sync + Sized { /// /// Drivers may use this to instantiate their [`DriverPlane`] object. fn new(device: &Device, args: Self::Args) -> impl PinInit; + + /// The optional [`drm_plane_helper_funcs.atomic_update`] hook for this plane. + /// + /// Drivers may use this to customize the atomic update phase of their [`Plane`] objects. If not + /// specified, this function is a no-op. + /// + /// [`drm_plane_helper_funcs.atomic_update`]: srctree/include/drm/drm_modeset_helper_vtables.h + fn atomic_update( + _plane: &Plane, + _new_state: PlaneStateMutator<'_, PlaneState>, + _old_state: &PlaneState, + _state: &AtomicStateMutator, + ) { + build_error::build_error("This should not be reachable") + } } /// The generated C vtable for a [`DriverPlane`]. @@ -931,3 +950,27 @@ fn (PlaneStateMutator<'a, OpaquePlaneState>) -> Self // - The cast to `drm_plane_state` is safe via `PlaneState`s type invariants. unsafe { bindings::__drm_atomic_helper_plane_reset(plane, KBox::into_raw(new).cast()) }; } + +unsafe extern "C" fn atomic_update_callback( + plane: *mut bindings::drm_plane, + state: *mut bindings::drm_atomic_state, +) { + // SAFETY: + // - We're guaranteed `plane` is of type `Plane` via type invariants. + // - We're guaranteed by DRM that `plane` is pointing to a valid initialized state. + let plane = unsafe { Plane::from_raw(plane) }; + + // SAFETY: DRM guarantees `state` points to a valid `drm_atomic_state` + let state = unsafe { AtomicStateMutator::new(NonNull::new_unchecked(state)) }; + + // SAFETY: Since we are in the atomic update callback, we're guaranteed by DRM that both the old + // and new atomic state are present within `state` + let (old_state, new_state) = unsafe { + ( + state.get_old_plane_state(plane).unwrap_unchecked(), + state.get_new_plane_state(plane).unwrap_unchecked(), + ) + }; + + T::atomic_update(plane, new_state, old_state, &state); +}