Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423345AbbD2Oml (ORCPT ); Wed, 29 Apr 2015 10:42:41 -0400 Received: from foss.arm.com ([217.140.101.70]:33386 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1423051AbbD2Omi (ORCPT ); Wed, 29 Apr 2015 10:42:38 -0400 Date: Wed, 29 Apr 2015 15:42:32 +0100 From: Catalin Marinas To: Suravee Suthikulpanit Cc: al.stone@linaro.org, arnd@arndb.de, linaro-acpi@lists.linaro.org, rjw@rjwysocki.net, will.deacon@arm.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, leo.duran@amd.com, hanjun.guo@linaro.org, msalter@redhat.com, grant.likely@linaro.org, Charles Garcia-Tobin , linux-arm-kernel@lists.infradead.org, lenb@kernel.org Subject: Re: [PATCH 1/2] arm/arm64: ACPI: Introduce CONFIG_ACPI_MUST_HAVE_CCA Message-ID: <20150429144232.GC18867@e104818-lin.cambridge.arm.com> References: <1430315049-4663-1-git-send-email-Suravee.Suthikulpanit@amd.com> <1430315049-4663-2-git-send-email-Suravee.Suthikulpanit@amd.com> <20150429140445.GA18867@e104818-lin.cambridge.arm.com> <5540EB27.8060507@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5540EB27.8060507@amd.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1948 Lines: 52 On Wed, Apr 29, 2015 at 09:31:03AM -0500, Suravee Suthikulpanit wrote: > > > On 04/29/2015 09:04 AM, Catalin Marinas wrote: > >On Wed, Apr 29, 2015 at 08:44:08AM -0500, Suravee Suthikulpanit wrote: > >> From ACPIv6 (http://www.uefi.org/sites/default/files/resources/ACPI_6.0.pdf), > >>section 6.2.17 _CCA states that ARM platforms require ACPI _CCA object to be > >>specified for DMA-cabpable devices. This patch introduces ACPI_MUST_HAVE_CCA > >>in arm and arm64 Kconfig to specify such requirement. > >> > >>Note that when _CCA is required, if it is missing in the DSDT. ACPI driver > >>will default to setting up devices as non-coherent. > >> > >>Signed-off-by: Mark Salter > >>Signed-off-by: Suravee Suthikulpanit > >>--- > >> arch/arm/Kconfig | 1 + > >> arch/arm64/Kconfig | 1 + > >> drivers/acpi/Kconfig | 3 +++ > >> 3 files changed, 5 insertions(+) > >> > >>diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > >>index 45df48b..2a0d036 100644 > >>--- a/arch/arm/Kconfig > >>+++ b/arch/arm/Kconfig > >>@@ -1,6 +1,7 @@ > >> config ARM > >> bool > >> default y > >>+ select ACPI_MUST_HAVE_CCA if ACPI > >> select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE > >> select ARCH_HAS_ELF_RANDOMIZE > >> select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST > > > >Any plans for ACPI on 32-bit ARM? > > Not that I am aware, but I could be totally wrong. The reason I am adding > this here for 32-bit ARM is because the ACPI spec mentioned this. > > If you think this is not necessary until we introduce ACPI for ARM32, it can > be removed. I think it should be removed (as long as ACPI cannot be selected on arm32). -- Catalin -- 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/