From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751270AbeDQAnu (ORCPT ); Mon, 16 Apr 2018 20:43:50 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:56114 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751060AbeDQAns (ORCPT ); Mon, 16 Apr 2018 20:43:48 -0400 Subject: Re: [PATCH 2/3] ACPI: SPCR: Add support for AMD CT/SZ To: Daniel Kurtz Cc: adurbin@chromium.org, "Rafael J. Wysocki" , Len Brown , "open list:ACPI" , open list Newsgroups: gmane.linux.kernel,gmane.linux.acpi.devel References: <20180314003655.12141-1-djkurtz@chromium.org> <20180314003655.12141-3-djkurtz@chromium.org> From: Jon Masters Organization: World Organi{s,z}ation of Broken Dreams Message-ID: <01bc6f27-57aa-d8e9-934b-191a128543cf@jonmasters.org> Date: Mon, 16 Apr 2018 20:43:46 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180314003655.12141-3-djkurtz@chromium.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/13/2018 08:36 PM, Daniel Kurtz wrote: > AMD Carrizo / Stoneyridge use a DesignWare 8250 UART that uses a special > earlycon setup handler to configure its input clock in order to compute > baud rate divisor registers. > Detect them by examining the OEMID field in the SPCR header, and pass > then pass uart type amdcz to earlycon. FYI I spoke with Microsoft some time ago about standardizing the ability to convey non-standard baud rates in the SPCR. If you're interested in driving, I can put you in touch with the right person over there. Jon. -- Computer Architect