From mboxrd@z Thu Jan  1 00:00:00 1970
From: hanjun.guo@linaro.org (Hanjun Guo)
Date: Fri, 02 Jan 2015 17:28:11 +0800
Subject: [PATCH v5 18/18] Documentation: ACPI for ARM64
In-Reply-To: <20150101200424.GB12770@xora-haswell.xora.org.uk>
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 <20150101200424.GB12770@xora-haswell.xora.org.uk>
Message-ID: <54A664AB.3030101@linaro.org>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Hi Graeme,

On 2015?01?02? 04:04, Graeme Gregory wrote:
> On Wed, Dec 31, 2014 at 04:34:46PM +0800, Hanjun Guo wrote:
>> On 2014?12?31? 04:13, ashwinc at codeaurora.org wrote:
>>> Hi Hanjun,
>>>
>>> Overall the document looks good to us. Some minor clarifications below.
>>>
>>>> ---------- Forwarded message ----------
>>>> From: Graeme Gregory <graeme.gregory@linaro.org>
>>>>
>>>> Add documentation for the guidelines of how to use ACPI
>>>> on ARM64.
>>>>
>>>> Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
>>>> Signed-off-by: Al Stone <al.stone@linaro.org>
>>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
>>>> ---
>>>>   Documentation/arm64/arm-acpi.txt |  323
>>>> ++++++++++++++++++++++++++++++++++++++
>>>>   1 file changed, 323 insertions(+)
>>>>   create mode 100644 Documentation/arm64/arm-acpi.txt
>>>>
>>>
>>> [..]
>>>
>>>> +Relationship with Device Tree
>>>> +-----------------------------
>>>
>>> [..]
>>>
>>>> +When booting using ACPI tables, the /chosen node in DT will still be
>>>> parsed
>>>> +to extract the kernel command line and initrd path.  No other section of
>>>> the
>>>> +DT will be used.
>>>
>>> Is this still true?
>>
>> No, we can booting the ACPI system in EFI stub without dtb. Catalin
>> also pointed out this issue, I will remove this paragraph.
>>
>
> The paragraph is still correct, the /chosen node is always present even
> if nothing else is.

Sorry for the confusing, I mean no dtb needed for the command line if
ACPI tables are available.

efi will create a empty dtb if no dtb found, and add the cmd line into
the new created dtb, I'm just wondering, can we remove the limitation
for passing the cmd line in /chosen node in the future?

Thanks
Hanjun