From mboxrd@z Thu Jan 1 00:00:00 1970 From: Catalin Marinas Subject: Re: [Linaro-acpi] [PATCH v7 04/17] ARM64 / ACPI: Introduce early_param for "acpi" and pass acpi=force to enable ACPI Date: Wed, 28 Jan 2015 18:14:53 +0000 Message-ID: <20150128181453.GG31752@e104818-lin.cambridge.arm.com> References: <1421247905-3749-1-git-send-email-hanjun.guo@linaro.org> <1421247905-3749-5-git-send-email-hanjun.guo@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Timur Tabi Cc: Mark Rutland , Rob Herring , "phoenix.liyi@huawei.com" , Robert Richter , "linux-acpi@vger.kernel.org" , Arnd Bergmann , "linaro-acpi@lists.linaro.org" , Marc Zyngier , Will Deacon , Randy Dunlap , "Rafael J. Wysocki" , lkml , "grant.likely@linaro.org" , "wangyijing@huawei.com" , Mark Brown , "hanjun.guo@linaro.org" , "jcm@redhat.com" , Olof Johansson , Bjorn Helgaas , "linux-arm-kernel@lists.infradead.org" , Jason Cooper List-Id: linux-acpi@vger.kernel.org On Wed, Jan 28, 2015 at 06:08:24PM +0000, Timur Tabi wrote: > On Wed, Jan 28, 2015 at 11:58 AM, Timur Tabi wrote: > > What is the reason to assume that DT is preferred over ACPI? I would > > have thought that if ACPI is present, then it means we're on an ARM64 > > server platform, and therefore it should be used. It seems silly to > > require acpi=force on every ARM64 server platform. > > So it looks like there's a whole conversation about this already in > this thread that I didn't notice. However, reading through all of it, > I still don't understand sure why the presence of ACPI tables is > insufficient to enable ACPI. Because ACPI on arm64 is still experimental, no matter how many people claim that it is production ready in their private setups. > In what situation would we want to ignore ACPI tables that are > present? When DT tables are also present (and for the first platforms, that's highly recommended, though not easily enforceable at the kernel level). -- Catalin