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Subject: Re: [PATCH] arm64: defconfig: enable EFI_ARMSTUB_DTB_LOADER
To:     Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc:     Grant Likely <grant.likely@secretlab.ca>,
        Olof Johansson <olof@lixom.net>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Arnd Bergmann <arnd@arndb.de>,
        BCM Kernel Feedback <bcm-kernel-feedback-list@broadcom.com>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Leif Lindholm <leif.lindholm@linaro.org>,
        Alexander Graf <agraf@suse.de>
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From:   Scott Branden <scott.branden@broadcom.com>
Message-ID: <1f8095f1-1f0c-0791-31c4-c7b986c4ce1f@broadcom.com>
Date:   Wed, 5 Sep 2018 10:27:55 -0700
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On 18-09-05 02:40 AM, Ard Biesheuvel wrote:
> On 4 September 2018 at 19:19, Scott Branden <scott.branden@broadcom.com> wrote:
>> Rather than introduce EFI_ARMSTUB_DTB_LOADER, why not have
>> the efistub use CONFIG_OF to determine whether it supports dtb= or not?
>>
>> That way ACPI-only distros disable devicetree support entirely.
>>
> Unfortunately, CONFIG_OF cannot be disabled on arm64 even on ACPI-only builds.
OF shouldn't be automatically selected in the arm64/Kconfig.  It should 
have a config
parmaeter like other archs as mips and arm.  I can submit a patch so it 
functions the
same way as other archs so it is not always selected.  It will be good 
to add a USE_OF
config options like the other archs (or simply remove the select from 
the Kconfig and choose OF directly in the defconfig.
This will have the added benefit of doing away with OF support when its 
not needed on an ARM64 platform.  ACPI is already not automatically 
selected for all ARM64 platforms, nor should devicetree.