From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hanjun Guo Subject: Re: [PATCH] ACPICA / hwreg: Use acpi_gbl_reduced_hardware to prevent accessing PM registers Date: Wed, 18 Sep 2013 17:28:25 +0800 Message-ID: <52397239.9080606@linaro.org> References: <1379066741-23689-1-git-send-email-hanjun.guo@linaro.org> <94F2FBAB4432B54E8AACC7DFDE6C92E36FEEBC6A@ORSMSX103.amr.corp.intel.com> <94F2FBAB4432B54E8AACC7DFDE6C92E36FEEC15B@ORSMSX103.amr.corp.intel.com> <52366F91.30204@linaro.org> <94F2FBAB4432B54E8AACC7DFDE6C92E36FEEC56A@ORSMSX103.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pd0-f174.google.com ([209.85.192.174]:63469 "EHLO mail-pd0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751615Ab3IRJbk (ORCPT ); Wed, 18 Sep 2013 05:31:40 -0400 Received: by mail-pd0-f174.google.com with SMTP id y13so6798282pdi.19 for ; Wed, 18 Sep 2013 02:31:40 -0700 (PDT) In-Reply-To: <94F2FBAB4432B54E8AACC7DFDE6C92E36FEEC56A@ORSMSX103.amr.corp.intel.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Moore, Robert" Cc: "'Rafael J. Wysocki'" , 'Len Brown' , "Box, David E" , "Zheng, Lv" , "'linux-acpi@vger.kernel.org'" , "'patches@linaro.org'" , "'linaro-kernel@lists.linaro.org'" , "'linaro-acpi@lists.linaro.org'" On 2013-9-17 1:26, Moore, Robert wrote: > + #define ACPI_REDUCED_HARDWARE TRUE > > The intent of this feature is of course, to remove all code that is not needed -- specifically for hardware-reduced machines where the size of the kernel is important. Ok, how about this patch below, is it reasonable to you? >>From b10bc1d2f9a3ff09abfb6990412aa1cf62d56937 Mon Sep 17 00:00:00 2001 From: Hanjun Guo Date: Wed, 18 Sep 2013 17:19:23 +0800 Subject: [PATCH] ACPI: Introduce CONFIG_ACPI_REDUCED_HARDWARE to enable reduced hardware If we want to enable reduced hardware ACPI on some platform (such as ARM), we need to modify the kernel code and set ACPI_REDUCED_HARDWARE to TRUE. This is not reasonable, so introduce a kernel config to enable it, and no need for kernel modification when we use hardware-reduced ACPI. Signed-off-by: Hanjun Guo --- drivers/acpi/Kconfig | 8 ++++++++ include/acpi/acconfig.h | 4 ++++ 2 files changed, 12 insertions(+) diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 0d7f6eb..1232a7b 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -413,6 +413,14 @@ config ACPI_BGRT data from the firmware boot splash. It will appear under /sys/firmware/acpi/bgrt/ . +config ACPI_REDUCED_HARDWARE + bool "Hardware-reduced ACPI support" + depends on ARM || ARM64 + help + This config adds support for Hardware-reduced ACPI. When this option + is selected, will generate a specialized version of ACPICA that ONLY + supports the ACPI 5.0 "reduced hardware". + source "drivers/acpi/apei/Kconfig" endif # ACPI diff --git a/include/acpi/acconfig.h b/include/acpi/acconfig.h index 1c16f82..15254f5 100644 --- a/include/acpi/acconfig.h +++ b/include/acpi/acconfig.h @@ -100,7 +100,11 @@ * ACPI PM timer * FACS table (Waking vectors and Global Lock) */ +#ifdef CONFIG_ACPI_REDUCED_HARDWARE +#define ACPI_REDUCED_HARDWARE TRUE +#else #define ACPI_REDUCED_HARDWARE FALSE +#endif /* CONFIG_ACPI_REDUCED_HARDWARE */ /****************************************************************************** * -- 1.7.9.5