Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751466AbaG1S22 (ORCPT ); Mon, 28 Jul 2014 14:28:28 -0400 Received: from service87.mimecast.com ([91.220.42.44]:37986 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750933AbaG1S20 convert rfc822-to-8bit (ORCPT ); Mon, 28 Jul 2014 14:28:26 -0400 Message-ID: <53D69665.5090709@arm.com> Date: Mon, 28 Jul 2014 19:28:53 +0100 From: Sudeep Holla User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Hanjun Guo , Catalin Marinas , "Rafael J. Wysocki" , Mark Rutland CC: Sudeep Holla , "graeme.gregory@linaro.org" , Arnd Bergmann , "grant.likely@linaro.org" , Will Deacon , Jason Cooper , Marc Zyngier , Bjorn Helgaas , Daniel Lezcano , Mark Brown , Robert Richter , Lv Zheng , Robert Moore , Lorenzo Pieralisi , Liviu Dudau , Randy Dunlap , Charles Garcia-Tobin , "linux-acpi@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 03/19] ARM64 / ACPI: Introduce lowlevel suspend function References: <1406206825-15590-1-git-send-email-hanjun.guo@linaro.org> <1406206825-15590-4-git-send-email-hanjun.guo@linaro.org> In-Reply-To: <1406206825-15590-4-git-send-email-hanjun.guo@linaro.org> X-OriginalArrivalTime: 28 Jul 2014 18:28:22.0503 (UTC) FILETIME=[B6736770:01CFAA91] X-MC-Unique: 114072819282301501 Content-Type: text/plain; charset=WINDOWS-1252; format=flowed Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 24/07/14 14:00, Hanjun Guo wrote: > From: Graeme Gregory > > acpi_wakeup_address is used on x86 as the address bios jumps into > when machine wakes up from suspend. As arm64 does not have such a > bios this mechanism will be provided by other means. But the define > is still required inside the acpi core. > > Introduce a null stub for acpi_suspend_lowlevel as this is also > required by core. This will be filled in when standards are > defined for arm64 ACPI global power states. > > Reviewed-by: Grant Likely > Signed-off-by: Graeme Gregory > Signed-off-by: Hanjun Guo > --- > arch/arm64/include/asm/acpi.h | 12 ++++++++++++ > arch/arm64/kernel/acpi.c | 7 +++++++ > 2 files changed, 19 insertions(+) > > diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h > index e8581ea..44b617f 100644 > --- a/arch/arm64/include/asm/acpi.h > +++ b/arch/arm64/include/asm/acpi.h > @@ -36,6 +36,18 @@ static inline bool acpi_has_cpu_in_madt(void) > return 1; > } > > +/* Low-level suspend routine. > + * > + * ACPI S-states for ARM64 have to be defined > + * and approved before doing anything else, maybe > + * we need update the ACPI spec, here we > + * just introduce function and macro needed by > + * ACPI core as IA64 did, and revisit them when > + * the spec is ready. > + */ > +extern int (*acpi_suspend_lowlevel)(void); > +#define acpi_wakeup_address 0 > + While I understand that this is temporary solution, but will this be sufficient to make sure we don't enter acpi_suspend_enter ? A brief look at acpi_suspend_enter showed access to write to ACPI_BITREG_SCI_ENABLE which might just explode. But if you are sure that it will not be executed, then it should be fine for now. Regards, Sudeep -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/