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 X-Spam-Level: X-Spam-Status: No, score=-7.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A8256C4338F for ; Wed, 18 Aug 2021 11:43:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7975361075 for ; Wed, 18 Aug 2021 11:43:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236046AbhHRLoa (ORCPT ); Wed, 18 Aug 2021 07:44:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235738AbhHRLo3 (ORCPT ); Wed, 18 Aug 2021 07:44:29 -0400 X-Greylist: delayed 523 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Wed, 18 Aug 2021 04:43:55 PDT Received: from mail.marcansoft.com (marcansoft.com [IPv6:2a01:298:fe:f::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0651BC0613CF for ; Wed, 18 Aug 2021 04:43:54 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) (Authenticated sender: marcan@marcan.st) by mail.marcansoft.com (Postfix) with ESMTPSA id 5889A41F72; Wed, 18 Aug 2021 11:43:50 +0000 (UTC) Subject: Re: [RFC PATCH 2/2] PCI: apple: Add driver for the Apple M1 To: Sven Peter , Marc Zyngier , Alyssa Rosenzweig Cc: linux-pci@vger.kernel.org, Bjorn Helgaas , Rob Herring , Lorenzo Pieralisi , =?UTF-8?Q?Krzysztof_Wilczy=c5=84ski?= , Stan Skowronek , Mark Kettenis , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <20210815042525.36878-1-alyssa@rosenzweig.io> <20210815042525.36878-3-alyssa@rosenzweig.io> <87a6lj17d1.wl-maz@kernel.org> <8650c850-2642-4582-ae97-a95134bda3e2@www.fastmail.com> From: Hector Martin Message-ID: <092a2de3-6760-6398-e4de-2b24d30ac856@marcan.st> Date: Wed, 18 Aug 2021 20:43:48 +0900 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 MIME-Version: 1.0 In-Reply-To: <8650c850-2642-4582-ae97-a95134bda3e2@www.fastmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: es-ES Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 15/08/2021 21.33, Sven Peter wrote: > The magic comes from the original Corellium driver. It first masks everything > except for the interrupts in the next line, then acks the interrupts it keeps > enabled and then probably wants to wait for PORT_INT_LINK_UP (or any of the > other interrupts which seem to indicate various error conditions) to fire but > instead polls for PORT_LINKSTS_UP. Let's not take any magic numbers from their drivers (or what macOS does, for that matter) without making an attempt to understand what they do, unless it becomes clear it's incomprehensible. This has already bit us in the past (the SError disable thing). -- Hector Martin (marcan@marcan.st) Public Key: https://mrcn.st/pub