From patchwork Mon Sep 30 23:10:05 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lyude Paul X-Patchwork-Id: 13817275 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 26199CEB2CD for ; Mon, 30 Sep 2024 23:40:22 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A4BA210E5A1; Mon, 30 Sep 2024 23:40:21 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="KUOh7f6k"; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id AE84310E5A1 for ; Mon, 30 Sep 2024 23:40:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1727739618; 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=HfyGQAtdmrvZOPwaMinkiOwAP5GbXOwQ1SJfQzgrIws=; b=KUOh7f6k8VnT+SPLmdngOee9Obg9pNI8LThDnKS0hSsw2f7QmxEczfZaYLVFWjhhEn9hbR aj1pkhzpHoks6Ys+cQSPgdbp6heOTwqF2U4KPo/C0g4FnvIerJ2VUYGihvDJ9I5iSV3md1 bjADv6fg83BneDPCxey+3Y/07t4I4n4= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-491-xZpGV_G_OmSZbwHMYykISQ-1; Mon, 30 Sep 2024 19:40:15 -0400 X-MC-Unique: xZpGV_G_OmSZbwHMYykISQ-1 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (unknown [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-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 071AE19560B7; Mon, 30 Sep 2024 23:40:13 +0000 (UTC) Received: from chopper.redhat.com (unknown [10.22.32.36]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id DD4DA3003DEC; Mon, 30 Sep 2024 23:40:08 +0000 (UTC) From: Lyude Paul To: dri-devel@lists.freedesktop.org, rust-for-linux@vger.kernel.org Cc: Asahi Lina , Danilo Krummrich , mcanal@igalia.com, airlied@redhat.com, zhiw@nvidia.com, cjia@nvidia.com, jhubbard@nvidia.com, Miguel Ojeda , Alex Gaynor , Wedson Almeida Filho , Boqun Feng , Gary Guo , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , linux-kernel@vger.kernel.org (open list) Subject: [WIP RFC v2 22/35] rust: drm/kms: Add DriverPlane::atomic_update() Date: Mon, 30 Sep 2024 19:10:05 -0400 Message-ID: <20240930233257.1189730-23-lyude@redhat.com> In-Reply-To: <20240930233257.1189730-1-lyude@redhat.com> References: <20240930233257.1189730-1-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 | 39 +++++++++++++++++++++++++++++++++++- 1 file changed, 38 insertions(+), 1 deletion(-) diff --git a/rust/kernel/drm/kms/plane.rs b/rust/kernel/drm/kms/plane.rs index d6e11a65cc101..506ed5ced1270 100644 --- a/rust/kernel/drm/kms/plane.rs +++ b/rust/kernel/drm/kms/plane.rs @@ -75,7 +75,7 @@ pub trait DriverPlane: Send + Sync + Sized { begin_fb_access: None, // TODO: someday? end_fb_access: None, // TODO: someday? atomic_check: None, - atomic_update: None, + atomic_update: if Self::HAS_ATOMIC_UPDATE { Some(atomic_update_callback::) } else { None }, atomic_enable: None, // TODO atomic_disable: None, // TODO atomic_async_check: None, // TODO @@ -103,6 +103,21 @@ 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: BorrowedPlaneState<'_, PlaneState>, + old_state: &PlaneState, + state: &AtomicStateMutator + ) { + build_error::build_error("This should not be reachable") + } } /// The generated C vtable for a [`DriverPlane`]. @@ -757,3 +772,25 @@ fn deref_mut(&mut self) -> &mut Self::Target { // - The cast to `drm_plane_state` is safe via `PlaneState`s type invariants. unsafe { bindings::__drm_atomic_helper_plane_reset(plane, Box::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); +}