From patchwork Mon Sep 30 23:10:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lyude Paul X-Patchwork-Id: 13817285 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 BBF3ECEB2CB for ; Mon, 30 Sep 2024 23:41:39 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4940110E5AB; Mon, 30 Sep 2024 23:41:39 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="PTowA6Wa"; 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 0482E10E5AB for ; Mon, 30 Sep 2024 23:41:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1727739697; 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=7t/iPh52Or/uRW+fztwWU5+XnAVyTy6rcl2tUGiZv4A=; b=PTowA6Wav4fccU0ARyTItRjaNdPNH+N4nqzl1oHcMunuidCbuK0kVWlIN80EqrDr36OIEP 0Syr+eLak5VshFODQYpl95zoFqybvduUvBi0XMKKwZ0BbEOdLV+YN6H2ZwJbde3E3C8dqd MfH5WqPa6qlHbmjnHpDSNBsKnr11yzU= Received: from mx-prod-mc-03.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-3-OWGYhbbOPTi0_jOaBzYfLg-1; Mon, 30 Sep 2024 19:41:35 -0400 X-MC-Unique: OWGYhbbOPTi0_jOaBzYfLg-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-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 3A46919192AC; Mon, 30 Sep 2024 23:41:27 +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 E539D3003DEC; Mon, 30 Sep 2024 23:41:22 +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 32/35] rust: drm/kms: Add Device::num_crtcs() Date: Mon, 30 Sep 2024 19:10:15 -0400 Message-ID: <20240930233257.1189730-33-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 binding for checking drm_device.num_crtcs. We'll need this in a moment for vblank support, since setting it up requires knowing the number of CRTCs that a driver has initialized. Signed-off-by: Lyude Paul --- rust/kernel/drm/kms.rs | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-) diff --git a/rust/kernel/drm/kms.rs b/rust/kernel/drm/kms.rs index 3edd90bc0025a..d0745b44ba9b6 100644 --- a/rust/kernel/drm/kms.rs +++ b/rust/kernel/drm/kms.rs @@ -253,10 +253,27 @@ pub fn mode_config_lock(&self) -> ModeConfigGuard<'_, T> { /// Return the number of registered [`Plane`](plane::Plane) objects on this [`Device`]. #[inline] - pub fn num_plane(&self) -> i32 { - // SAFETY: The only context which this could change is before registration, which must be - // single-threaded anyway - so it's safe to just read this value - unsafe { (*self.as_raw()).mode_config.num_total_plane } + pub fn num_plane(&self) -> u32 { + // SAFETY: + // * This can only be modified during the single-threaded context before registration, so + // this is safe + // * num_total_plane could be >= 0, but no less - so casting to u32 is fine (and better to + // prevent errors) + unsafe { (*self.as_raw()).mode_config.num_total_plane as u32 } + } + + /// Return the number of registered CRTCs + /// TODO: while `num_crtc` is of i32, that type actually makes literally no sense here and just + /// causes problems and unecessary casts. Same for num_plane(). So, fix that at some point (we + /// will never get n < 0 anyway) + #[inline] + pub fn num_crtcs(&self) -> u32 { + // SAFETY: + // * This can only be modified during the single-threaded context before registration, so + // this is safe + // * num_crtc could be >= 0, but no less - so casting to u32 is fine (and better to prevent + // errors) + unsafe { (*self.as_raw()).mode_config.num_crtc as u32 } } }