From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [RFC 1/2] ACPI: activate&export acpi_os_get_physical_address Date: Fri, 01 May 2015 03:45:52 +0200 Message-ID: <2766179.6BuP3vhKAH@vostro.rjw.lan> References: <20150430181025.GC40200@fury.dvhart.com> <4189370.scsJsnLdx0@vostro.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7Bit Return-path: Received: from v094114.home.net.pl ([79.96.170.134]:54820 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753179AbbEABU6 (ORCPT ); Thu, 30 Apr 2015 21:20:58 -0400 In-Reply-To: <4189370.scsJsnLdx0@vostro.rjw.lan> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Darren Hart , Matthew Garrett Cc: Kast Bernd , corentin.chary@gmail.com, lenb@kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, acpi4asus-user@lists.sourceforge.net, platform-driver-x86@vger.kernel.org On Friday, May 01, 2015 03:32:29 AM Rafael J. Wysocki wrote: > On Thursday, April 30, 2015 11:10:25 AM Darren Hart wrote: > > On Wed, Apr 22, 2015 at 04:12:24PM +0200, Kast Bernd wrote: > > > acpi_os_get_physical_address will be needed by an acpi driver (asus-wmi.c). > > > Additionally it could be used by dell-laptop.c instead of directly calling virt_to_phys. > > > > > > acpi_os_get_physical_address gets exported and ACPI_FUTURE_USAGE is removed > > > > > > > Hrm, well... this doesn't get rid of virt_to_phys, it just wraps it really. I'm > > not sure that makes this any more acceptable than the original from Felipe - but > > that's not my call. > > Use virt_to_phys() if you need to. > > This one is in case ACPICA needs to get the virtual-to-physical mapping (hence > ACPI_FUTURE_USAGE). More to the point, the reason why virt_to_phys() needs to be used in patch [2/2] seems to be a nasty hack in the ASUS AML that pretty much expects us to provide the physical address as an argument. And I don't really understand the Matthew's comment regarding limiting operation regions to system memory. This is about a specific operation region (which BTW only seems to be used as a means to access system memory at the location pointed to by the arg) in that particular method. Matthew? -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.