From patchwork Thu Dec 12 16:33:43 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Danilo Krummrich X-Patchwork-Id: 13905623 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0F61923A1B3; Thu, 12 Dec 2024 16:36:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734021381; cv=none; b=KJfmn31NLvK5KFooCSDky2kSOCrHdnUOCcEuk9bMk7ZjO/cJHn30iKgRVSI41kbPkPijG/zInkqwCn/pyPNz1u5f+CZi9PKje1bt2wXVW6z0rdYPX+TE1eiV4qmCZB1DTykE4StmOo5GRV2ZsuGhuNe8cNT6TTX+vLAqzdqQmnY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734021381; c=relaxed/simple; bh=amaguJCYxDUqc57XLu1S9GMe5x6nv8/1Wsg07UQE+kU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YyV0mTRjCAU0Obb5LtnwiXp+RNx03jjwN9ng4qBPGryeCD4W3VEynhpEepolDrjd72LrB+SmlA57nP32Fyoz93v9Kj3c5pedhJum+oJILHuRzTLZBtr0RaeQzkpW9FduWiJ3HE0Dz9hVdXwX+cVHhe2BIp/Hq1Lu0dNFoyj8oZQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=M1GkefJu; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="M1GkefJu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 090FFC4CEDD; Thu, 12 Dec 2024 16:36:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1734021379; bh=amaguJCYxDUqc57XLu1S9GMe5x6nv8/1Wsg07UQE+kU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M1GkefJuk7Ct1CdGtlsu17N1+i71nTnZJJu/GBTZEokplAlia3fRZJ5ayGWRvI9qy x87t+jxrgSgu0YMpv0obquQ/Tso8MssrxOSW0fCc6yCtBIgOlCxFsjScT+uFr7WtsR EckspMjrgQBJM4IuNL0L1DRW0BJ1DvOe+Vlw3/BxREFNatz79w1kVocCom5hFM/cBU FfGQc9RIC1z+yHGb4i3+ZoTXwJLHuayPRdDftyVUrIQgsRAsbltURvwz22F/v8B8t/ UtiP7pZ+kmtsy5FIVgaDE/BNfmlzITYVS42dfuJZrBfcRfZueEVyoQH8cs5LWGfwQZ 5lWfeTcZmlBsg== From: Danilo Krummrich To: gregkh@linuxfoundation.org, rafael@kernel.org, bhelgaas@google.com, ojeda@kernel.org, alex.gaynor@gmail.com, boqun.feng@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com, benno.lossin@proton.me, tmgross@umich.edu, a.hindborg@samsung.com, aliceryhl@google.com, airlied@gmail.com, fujita.tomonori@gmail.com, lina@asahilina.net, pstanner@redhat.com, ajanulgu@redhat.com, lyude@redhat.com, robh@kernel.org, daniel.almeida@collabora.com, saravanak@google.com, dirk.behme@de.bosch.com, j@jannau.net, fabien.parent@linaro.org, chrisi.schrefl@gmail.com, paulmck@kernel.org Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, devicetree@vger.kernel.org, rcu@vger.kernel.org, Danilo Krummrich Subject: [PATCH v6 12/16] rust: of: add `of::DeviceId` abstraction Date: Thu, 12 Dec 2024 17:33:43 +0100 Message-ID: <20241212163357.35934-13-dakr@kernel.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241212163357.35934-1-dakr@kernel.org> References: <20241212163357.35934-1-dakr@kernel.org> Precedence: bulk X-Mailing-List: rcu@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 `of::DeviceId` is an abstraction around `struct of_device_id`. This is used by subsequent patches, in particular the platform bus abstractions, to create OF device ID tables. Reviewed-by: Rob Herring (Arm) Signed-off-by: Danilo Krummrich --- MAINTAINERS | 1 + rust/kernel/lib.rs | 1 + rust/kernel/of.rs | 60 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 62 insertions(+) create mode 100644 rust/kernel/of.rs diff --git a/MAINTAINERS b/MAINTAINERS index b15eb7c6b23f..025a279ac8ca 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17502,6 +17502,7 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git F: Documentation/ABI/testing/sysfs-firmware-ofw F: drivers/of/ F: include/linux/of*.h +F: rust/kernel/of.rs F: scripts/dtc/ F: tools/testing/selftests/dt/ K: of_overlay_notifier_ diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs index 1dc7eda6b480..27f914b0769b 100644 --- a/rust/kernel/lib.rs +++ b/rust/kernel/lib.rs @@ -56,6 +56,7 @@ pub mod miscdevice; #[cfg(CONFIG_NET)] pub mod net; +pub mod of; pub mod page; pub mod pid_namespace; pub mod prelude; diff --git a/rust/kernel/of.rs b/rust/kernel/of.rs new file mode 100644 index 000000000000..04f2d8ef29cb --- /dev/null +++ b/rust/kernel/of.rs @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Device Tree / Open Firmware abstractions. + +use crate::{bindings, device_id::RawDeviceId, prelude::*}; + +/// IdTable type for OF drivers. +pub type IdTable = &'static dyn kernel::device_id::IdTable; + +/// An open firmware device id. +#[repr(transparent)] +#[derive(Clone, Copy)] +pub struct DeviceId(bindings::of_device_id); + +// SAFETY: +// * `DeviceId` is a `#[repr(transparent)` wrapper of `struct of_device_id` and does not add +// additional invariants, so it's safe to transmute to `RawType`. +// * `DRIVER_DATA_OFFSET` is the offset to the `data` field. +unsafe impl RawDeviceId for DeviceId { + type RawType = bindings::of_device_id; + + const DRIVER_DATA_OFFSET: usize = core::mem::offset_of!(bindings::of_device_id, data); + + fn index(&self) -> usize { + self.0.data as _ + } +} + +impl DeviceId { + /// Create a new device id from an OF 'compatible' string. + pub const fn new(compatible: &'static CStr) -> Self { + let src = compatible.as_bytes_with_nul(); + // Replace with `bindings::of_device_id::default()` once stabilized for `const`. + // SAFETY: FFI type is valid to be zero-initialized. + let mut of: bindings::of_device_id = unsafe { core::mem::zeroed() }; + + // TODO: Use `clone_from_slice` once the corresponding types do match. + let mut i = 0; + while i < src.len() { + of.compatible[i] = src[i] as _; + i += 1; + } + + Self(of) + } +} + +/// Create an OF `IdTable` with an "alias" for modpost. +#[macro_export] +macro_rules! of_device_table { + ($table_name:ident, $module_table_name:ident, $id_info_type: ty, $table_data: expr) => { + const $table_name: $crate::device_id::IdArray< + $crate::of::DeviceId, + $id_info_type, + { $table_data.len() }, + > = $crate::device_id::IdArray::new($table_data); + + $crate::module_device_table!("of", $module_table_name, $table_name); + }; +}