From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 247CDC433FE for ; Tue, 4 Oct 2022 21:14:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229651AbiJDVOm (ORCPT ); Tue, 4 Oct 2022 17:14:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229630AbiJDVOk (ORCPT ); Tue, 4 Oct 2022 17:14:40 -0400 Received: from ciao.gmane.io (ciao.gmane.io [116.202.254.214]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 70D9A190 for ; Tue, 4 Oct 2022 14:14:34 -0700 (PDT) Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1ofpFI-000847-Me for linux-serial@vger.kernel.org; Tue, 04 Oct 2022 23:14:32 +0200 X-Injected-Via-Gmane: http://gmane.org/ To: linux-serial@vger.kernel.org From: Grant Edwards Subject: Re: kernel 5.19.8: "Oxford Semiconductor Ltd OXPCIe952 Dual Native 950 UART" gets wrong baudrate (PCI ID 1415:c158) Date: Tue, 4 Oct 2022 21:14:28 -0000 (UTC) Message-ID: References: User-Agent: slrn/1.0.3 (Linux) Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On 2022-10-04, Grant Edwards wrote: > I just ran into what I think is the same problem when upgrading from > 5.10.76 to 5.15.68 (sorry I don't have any intermediate kernel > versions to test with). This is an oxford quad 950 board that has > worked flawlessly for many years. Now the baud rates are all wrong. > > [...] After reading through the thread a third time, I tried enabling CONFIG_SERIAL_8250_16550A_VARIANTS in my 6.15.69 kernel, and my quad Oxford board works again. The first two times I read through the thread I misunderstood the statement Can you please confirm that you have the CONFIG_SERIAL_8250_16550A_VARIANTS option disabled (default to "off" for x86 only)? as meaning that you should disable that option as a prerequisite to making it work. So I checked to make sure it was disabled (it was). Yes, it's obvious now what was meant was that having it disabled explains the previous observations. -- Grant