From patchwork Fri Jun 13 20:06:05 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julius Werner X-Patchwork-Id: 359672 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id D53E51400AB for ; Sat, 14 Jun 2014 06:06:27 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753047AbaFMUG0 (ORCPT ); Fri, 13 Jun 2014 16:06:26 -0400 Received: from mail-pa0-f53.google.com ([209.85.220.53]:56225 "EHLO mail-pa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751836AbaFMUG0 (ORCPT ); Fri, 13 Jun 2014 16:06:26 -0400 Received: by mail-pa0-f53.google.com with SMTP id kx10so2474964pab.12 for ; Fri, 13 Jun 2014 13:06:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id; bh=FnQMHRV2Bqqw3S8UDl8NxB76oIxKqy92ORUbikf3Kkg=; b=dcKyDP7miuMWIJCq0jUWbVfJbFK5HwZtNlR2dqvVyfoGShLjjSdkUwjl0WuabQgSTj JdtckWRNgfkXkb6V+5HdO1+WHA5u9E5mVw22OCfax8yV89djye4FEv1AeNHYcJ0xeRVJ 2ozVtnqbJ7Ze8KWiWa/GU3Uvjl4bbX1a4+Yh8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=FnQMHRV2Bqqw3S8UDl8NxB76oIxKqy92ORUbikf3Kkg=; b=P2c1TWXd07zcEB7/M7xibenJXc5OL75iXkWk86xCvVDpttflnTxwMUd7tic4gMCRrO Wv9dDZxjHJYx3WTRmbigOZAJ4aHSAYCuskxDA3OpIVoJve4oy4Vw2Anh8vqxL8nGxDGI ecdhLRqqjZOTWEF1cDTfyGqic4w86hkB4tOUL1L5eW9xR7ZQu+emKiGZEzqPDskbUhzL SF8ZXPkIHEm30rlnGNwqTctnx+6PcFrPGpKlJHjSLK/Q7fCdJ3Rck3WJwA1tUUe1hSMg MZxiuxc7CKhgISakRjAtbFEddrCrhnOB669lrhGxK8i+tEBxeq4lAKIU8gPK6bbdQzwf 4qww== X-Gm-Message-State: ALoCoQkftF9M2naXbIc9y5N587X9N2qH0FvWg8/NPUWmW3p5abfUkvqRMHwNxjQj+JmWuCObtvsQ X-Received: by 10.66.150.169 with SMTP id uj9mr5884078pab.148.1402689985431; Fri, 13 Jun 2014 13:06:25 -0700 (PDT) Received: from jwerner-linux.mtv.corp.google.com (jwerner-linux.mtv.corp.google.com [172.22.72.75]) by mx.google.com with ESMTPSA id op3sm5103623pbc.40.2014.06.13.13.06.24 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 13 Jun 2014 13:06:24 -0700 (PDT) From: Julius Werner To: Rob Herring Cc: Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Stephen Warren , Doug Anderson , Olof Johansson , Stefan Reinauer , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Julius Werner Subject: [PATCH] firmware: Add device tree binding for coreboot Date: Fri, 13 Jun 2014 13:06:05 -0700 Message-Id: <1402689965-19397-1-git-send-email-jwerner@chromium.org> X-Mailer: git-send-email 2.0.0.526.g5318336 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org This patch adds documentation describing a device tree binding for the coreboot firmware project (www.coreboot.org). It is meant to be dynamically added during boot and contains address definitions for the coreboot table (a list of variable-sized descriptors providing information about various compile- and run-time generated firmware parameters) and the CBMEM area (the structure containing most run-time resident memory regions set up by coreboot). These definitions allow kernel drivers to easily access data contained in and pointed to by these regions (such as coreboot's in-memory log). (An example implementation can be seen at http://crosreview.com/203371, which will be submitted at a later point.) Signed-off-by: Julius Werner --- .../devicetree/bindings/firmware/coreboot.txt | 28 ++++++++++++++++++++++ 1 file changed, 28 insertions(+) create mode 100644 Documentation/devicetree/bindings/firmware/coreboot.txt diff --git a/Documentation/devicetree/bindings/firmware/coreboot.txt b/Documentation/devicetree/bindings/firmware/coreboot.txt new file mode 100644 index 0000000..89d7bf3 --- /dev/null +++ b/Documentation/devicetree/bindings/firmware/coreboot.txt @@ -0,0 +1,28 @@ +COREBOOT firmware information + +The device tree node to communicate the location of coreboot's memory-resident +bookkeeping structures to the kernel. Since coreboot itself cannot boot a +device-tree-based kernel (yet), this node needs to be inserted by a +second-stage bootloader (a coreboot "payload"). + +Required properties: + - compatible: Should be "coreboot" + - reg: Address and length of the following two memory regions, in order: + 1.) The coreboot table. This is a list of variable-sized descriptors + that contain various compile- and run-time generated firmware + parameters. It is identified by the magic string "LBIO" in its first + four bytes. See coreboot's src/include/boot/coreboot_tables.h for + details. + 2.) The CBMEM area. This is a downward-growing memory region used by + coreboot to dynamically allocate data structures that remain resident. + It may or may not include the coreboot table as one of its members. It + is identified by a root node descriptor with the magic number + 0xc0389479 that resides in the topmost 8 bytes of the area. See + coreboot's src/lib/dynamic_cbmem.c for details. + +Example: + firmware { + compatible = "coreboot"; + reg = <0xfdfea000 0x264>, + <0xfdfea000 0x16000>; + };