From mboxrd@z Thu Jan 1 00:00:00 1970 From: timur@codeaurora.org (Timur Tabi) Date: Wed, 28 Jan 2015 12:18:44 -0600 Subject: [Linaro-acpi] [PATCH v7 04/17] ARM64 / ACPI: Introduce early_param for "acpi" and pass acpi=force to enable ACPI In-Reply-To: <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> <20150128181453.GG31752@e104818-lin.cambridge.arm.com> Message-ID: <54C92804.5090806@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 01/28/2015 12:14 PM, Catalin Marinas wrote: >> >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. Fair enough. Does this mean that passing "acpi=force" on the kernel command line is a requirement for ARM64 servers? >> >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). My understanding is that the EFI stub creates a device tree (and it contains some important information), so I don't understand how we can ever have an ACPI-only platform on ARM64 servers. -- Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.