From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751913AbaIJHb7 (ORCPT ); Wed, 10 Sep 2014 03:31:59 -0400 Received: from szxga01-in.huawei.com ([119.145.14.64]:37101 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751038AbaIJHb4 (ORCPT ); Wed, 10 Sep 2014 03:31:56 -0400 Message-ID: <540FFE0B.7070400@huawei.com> Date: Wed, 10 Sep 2014 15:30:19 +0800 From: Hanjun Guo User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.0.1 MIME-Version: 1.0 To: Catalin Marinas , "hanjun.guo@linaro.org" CC: "Rafael J. Wysocki" , Mark Rutland , Olof Johansson , "grant.likely@linaro.org" , "graeme.gregory@linaro.org" , Arnd Bergmann , Sudeep Holla , Will Deacon , Jason Cooper , Marc Zyngier , Bjorn Helgaas , Daniel Lezcano , Mark Brown , Rob Herring , 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" , "linaro-acpi@lists.linaro.org" , Al Stone , "Tomasz Nowicki" Subject: Re: [PATCH v3 02/17] ARM64 / ACPI: Get RSDP and ACPI boot-time tables References: <1409583475-6978-1-git-send-email-hanjun.guo@linaro.org> <1409583475-6978-3-git-send-email-hanjun.guo@linaro.org> <20140909162648.GE2910@arm.com> In-Reply-To: <20140909162648.GE2910@arm.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.17.188] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014/9/10 0:26, Catalin Marinas wrote: > On Mon, Sep 01, 2014 at 03:57:40PM +0100, Hanjun Guo wrote: >> diff --git a/arch/arm64/include/asm/acenv.h b/arch/arm64/include/asm/acenv.h >> new file mode 100644 >> index 0000000..3899ee6 >> --- /dev/null >> +++ b/arch/arm64/include/asm/acenv.h >> @@ -0,0 +1,18 @@ >> +/* >> + * ARM64 specific ACPICA environments and implementation >> + * >> + * Copyright (C) 2014, Linaro Ltd. >> + * Author: Hanjun Guo >> + * Author: Graeme Gregory >> + * >> + * This program is free software; you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License version 2 as >> + * published by the Free Software Foundation. >> + */ >> + >> +#ifndef _ASM_ACENV_H >> +#define _ASM_ACENV_H >> + >> +#define ACPI_FLUSH_CPU_CACHE() WARN_ONCE(1, "Not currently supported on ARM64") > > Does this mean that it will be supported at some point? Looking at the > places where this function is called, I don't really see how this would > ever work on ARM. Which means that we add such macro just to be able to > compile code that would never be used on arm64. I would rather see the > relevant ACPI files only compiled on x86/IA-64 rather than arm64. > >> diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c >> new file mode 100644 >> index 0000000..9252f72 >> --- /dev/null >> +++ b/arch/arm64/kernel/acpi.c > > [...] > >> +/* >> + * acpi_boot_table_init() called from setup_arch(), always. >> + * 1. find RSDP and get its address, and then find XSDT >> + * 2. extract all tables and checksums them all >> + * >> + * We can parse ACPI boot-time tables such as MADT after >> + * this function is called. >> + */ >> +void __init acpi_boot_table_init(void) >> +{ >> + /* If acpi_disabled, bail out */ >> + if (acpi_disabled) >> + return; > > So at this point, there wouldn't be anything yet to set acpi_disabled to > 1, unless !CONFIG_ACPI. > >> + >> + /* Initialize the ACPI boot-time table parser. */ >> + if (acpi_table_init()) >> + disable_acpi(); > > Do you need anything more to add to this function later? Otherwise, just > call it in setup_arch() directly (maybe dependent on > IS_ENABLED(CONFIG_ACPI) or just create an equivalent dummy > acpi_table_init() when not configured). We add FADT parse function to this function later. > >> diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c >> index c96172a..fb7cc0e 100644 >> --- a/arch/arm64/kernel/setup.c >> +++ b/arch/arm64/kernel/setup.c >> @@ -43,6 +43,7 @@ >> #include >> #include >> #include >> +#include >> >> #include >> #include >> @@ -385,6 +386,9 @@ void __init setup_arch(char **cmdline_p) >> efi_init(); >> arm64_memblock_init(); >> >> + /* Parse the ACPI tables for possible boot-time configuration */ >> + acpi_boot_table_init(); > > Is there any dummy acpi_boot_table_init() when !CONFIG_ACPI? I couldn't > see one in this patch, so I don't see how this would compile when ACPI > is disabled. There is a stub function in linux/acpi.h when ACPI is disabled. Thanks Hanjun