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Message-ID: <1519812442.10722.248.camel@linux.intel.com>
Subject: Re: [PATCH] arm64/acpi: make ACPI boot preference configurable
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Bhupesh Sharma <bhsharma@redhat.com>,
        Jonathan Toppins <jtoppins@redhat.com>
Cc:     linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        astone@redhat.com, Jonathan Masters <jcm@redhat.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>, rafael.j.wysocki@intel.com,
        Ingo Molnar <mingo@kernel.org>,
        Prarit Bhargava <prarit@redhat.com>,
        James Morse <james.morse@arm.com>, linux-kernel@vger.kernel.org
Date:   Wed, 28 Feb 2018 12:07:22 +0200
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On Wed, 2018-02-28 at 00:29 +0530, Bhupesh Sharma wrote:
> On Tue, Feb 27, 2018 at 8:14 PM, Jonathan Toppins <jtoppins@redhat.com
> > wrote:
> > On 02/27/2018 07:40 AM, Bhupesh Sharma wrote:
> > > 

> > For arm64 DT is suppose to *not* be the preferred method, yet still
> > DT
> > is preferred if the firmware provides both tables to the kernel.

> However several arm64 products in embedded applications are still not
> SBSA/SBBR compliant (and I have worked on a couple of such
> implementations earlier) and still use bootloaders like u-boot (and
> also closed-source implementations) which have no support for ACPI
> currently and still rely on a DT to pass the system hardware
> information to the kernel.

> So far only open source implementation of a ACPI compliant firmware is
> EDK2/UEFI which supports ACPI as the preferred boot method

You mean for non-x86?

>  and I am
> not sure if all u-boot/in-house firmware implementations are planned
> to be ported over to EDK2/UEFI for embedded applications.

Why do you need that? ACPI (if you are talking about ACPI only, w/o EFI)
is supported in U-Boot for few x86 SoCs/platforms. Moreover, one of them
had never been shipped with ACPI/EFI complaint services in firmware and
ACPI layer is purely done in U-Boot.

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy