From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933189AbeCSK5R (ORCPT ); Mon, 19 Mar 2018 06:57:17 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:59975 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932296AbeCSK5Q (ORCPT ); Mon, 19 Mar 2018 06:57:16 -0400 Date: Mon, 19 Mar 2018 11:57:04 +0100 (CET) From: Thomas Gleixner To: Anshuman Gupta cc: Rajneesh Bhardwaj , x86@kernel.org, mingo@redhat.com, hpa@zytor.com, rjw@rjwysocki.net, andriy.shevchenko@linux.intel.com, linux-kernel@vger.kernel.org, Alan Cox Subject: Re: [PATCH v2] x86: i8237: Register based on FADT legacy boot flag In-Reply-To: <20180319104627.GA2959@anshuman.gupta@intel.com> Message-ID: References: <1521004627-30329-1-git-send-email-rajneesh.bhardwaj@intel.com> <20180319104627.GA2959@anshuman.gupta@intel.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 19 Mar 2018, Anshuman Gupta wrote: > On Wed, Mar 14, 2018 at 04:07:43PM +0100, Thomas Gleixner wrote: > > On Wed, 14 Mar 2018, Rajneesh Bhardwaj wrote: > > > + * support 8237 DMA or bus mastering from LPC. Platform firmware > > > + * must announce the support for such legacy devices via > > > + * ACPI_FADT_LEGACY_DEVICES field in FADT table. > > > + */ > > > + if (!x86_platform.legacy.devices.pnpbios && dmi_get_bios_year() >= 2017) > > > > Please use arch_pnpbios_disabled() and explain why you need that year > arch_pnpbios_disabled is defined only when CONFIG_PNPBIOS is set, which may > not be true for all configurations. The please create a helper function x86_pnpbios_disabled() and use that one in arch_pnp_bios_disabled() and in your new code. > > check. If there is no pnpbios then why is the year interesting and why > > would anyone trust something which comes from BIOS? > > Modern bios fsp have started using to use ACPI_FADT_LEGACY_DEVICES field in > FADT table, that is the reason we require a year check for BIOS. > https://review.coreboot.org/#/c/coreboot/+/23833/ > https://review.coreboot.org/#/c/coreboot/+/23835/ Sorry, this gerrit stuff is unreadable. Please explain it in your own words. You have to do that anyway as that information wants to be in a comment or at least in the change log. Thanks, tglx