From patchwork Wed Mar 5 22:59:44 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lyude Paul X-Patchwork-Id: 14003656 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 6AC84C19F32 for ; Wed, 5 Mar 2025 23:09:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CC82310E863; Wed, 5 Mar 2025 23:09:01 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="SxLQxawg"; 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 B4DA810E863 for ; Wed, 5 Mar 2025 23:08:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1741216138; 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=0oBqLHoJsFA0rDr7+FKi6nHZ+YcDKW3Lfid1N4qEKas=; b=SxLQxawg8YNaO1Z9LIcJqkTI4rNIBh4VdDT8BdDmkP5KmGadUymu6pG0rmbH8IW9th8vOf /9Hi/I8vUl9V0ZPa9HCqzqWVhjBfcywf+lMT9fmOmN8LgVr8jExkoFw/E/a+3n+SnuqZrI 8TQlpvL0kjU+k2G353qGgMBScZsb3Mw= 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-287-OiC-7E2VMbeGGViGqm6hkg-1; Wed, 05 Mar 2025 18:08:45 -0500 X-MC-Unique: OiC-7E2VMbeGGViGqm6hkg-1 X-Mimecast-MFC-AGG-ID: OiC-7E2VMbeGGViGqm6hkg_1741216119 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 94E071800257; Wed, 5 Mar 2025 23:08:39 +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 3944D300019E; Wed, 5 Mar 2025 23:08:35 +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 28/33] rust: drm/kms: Add DriverCrtc::atomic_enable() and atomic_disable() Date: Wed, 5 Mar 2025 17:59:44 -0500 Message-ID: <20250305230406.567126-29-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" Optional trait methods for implementing the atomic_enable and atomic_disable callbacks of a CRTC. Signed-off-by: Lyude Paul --- rust/kernel/drm/kms/crtc.rs | 88 ++++++++++++++++++++++++++++++++++++- 1 file changed, 86 insertions(+), 2 deletions(-) diff --git a/rust/kernel/drm/kms/crtc.rs b/rust/kernel/drm/kms/crtc.rs index 131d10505ba07..9026d0911aa86 100644 --- a/rust/kernel/drm/kms/crtc.rs +++ b/rust/kernel/drm/kms/crtc.rs @@ -76,8 +76,16 @@ pub trait DriverCrtc: Send + Sync + Sized { }, helper_funcs: bindings::drm_crtc_helper_funcs { - atomic_disable: None, - atomic_enable: None, + atomic_disable: if Self::HAS_ATOMIC_DISABLE { + Some(atomic_disable_callback::) + } else { + None + }, + atomic_enable: if Self::HAS_ATOMIC_ENABLE { + Some(atomic_enable_callback::) + } else { + None + }, atomic_check: if Self::HAS_ATOMIC_CHECK { Some(atomic_check_callback::) } else { @@ -170,6 +178,34 @@ fn atomic_flush( ) { build_error::build_error("This should never be reachable") } + + /// The optional [`drm_crtc_helper_funcs.atomic_enable`] hook. + /// + /// This hook will be called before enabling a [`Crtc`] in an atomic commit. + /// + /// [`drm_crtc_helper_funcs.atomic_enable`]: srctree/include/drm/drm_modeset_helper_vtables.h + fn atomic_enable( + _crtc: &Crtc, + _old_state: &CrtcState, + _new_state: CrtcStateMutator<'_, CrtcState>, + _state: &AtomicStateMutator, + ) { + build_error::build_error("This should never be reachable") + } + + /// The optional [`drm_crtc_helper_funcs.atomic_disable`] hook. + /// + /// This hook will be called before disabling a [`Crtc`] in an atomic commit. + /// + /// [`drm_crtc_helper_funcs.atomic_disable`]: srctree/include/drm/drm_modeset_helper_vtables.h + fn atomic_disable( + _crtc: &Crtc, + _old_state: &CrtcState, + _new_state: CrtcStateMutator<'_, CrtcState>, + _state: &AtomicStateMutator, + ) { + build_error::build_error("This should never be reachable") + } } /// The generated C vtable for a [`DriverCrtc`]. @@ -1004,3 +1040,51 @@ fn vtable(&self) -> *const Self::Vtable { T::atomic_flush(crtc, old_state, new_state, &state); } + +unsafe extern "C" fn atomic_enable_callback( + crtc: *mut bindings::drm_crtc, + state: *mut bindings::drm_atomic_state, +) { + // SAFETY: + // - We're guaranteed `crtc` is of type `Crtc` via type invariants. + // - We're guaranteed by DRM that `crtc` is pointing to a valid initialized state. + let crtc = unsafe { Crtc::from_raw(crtc) }; + + // SAFETY: DRM never passes an invalid ptr for `state` + let state = unsafe { AtomicStateMutator::new(NonNull::new_unchecked(state)) }; + + // SAFETY: We're in an atomic enable callback, so we know that both the new and old state are + // present + let (old_state, new_state) = unsafe { + ( + state.get_old_crtc_state(crtc).unwrap_unchecked(), + state.get_new_crtc_state(crtc).unwrap_unchecked(), + ) + }; + + T::atomic_enable(crtc, old_state, new_state, &state); +} + +unsafe extern "C" fn atomic_disable_callback( + crtc: *mut bindings::drm_crtc, + state: *mut bindings::drm_atomic_state, +) { + // SAFETY: + // - We're guaranteed `crtc` points to a valid instance of `drm_crtc` + // - We're guaranteed that `crtc` is of type `Plane` by `DriverPlane`s type invariants. + let crtc = unsafe { Crtc::from_raw(crtc) }; + + // SAFETY: We're guaranteed that `state` points to a valid `drm_crtc_state` by DRM + let state = unsafe { AtomicStateMutator::new(NonNull::new_unchecked(state)) }; + + // SAFETY: We're in an atomic commit callback, so we know that both the new and old state are + // present + let (old_state, new_state) = unsafe { + ( + state.get_old_crtc_state(crtc).unwrap_unchecked(), + state.get_new_crtc_state(crtc).unwrap_unchecked(), + ) + }; + + T::atomic_disable(crtc, old_state, new_state, &state); +}