[PATCH v3 00/17] Introduce ACPI for ARM64 based on ACPI 5.1

[Jon Masters]

On 09/11/2014 09:49 AM, Will Deacon wrote:
> Hi Grant,
> 
> On Thu, Sep 11, 2014 at 02:29:34PM +0100, Grant Likely wrote:
>> On Mon,  1 Sep 2014 22:57:38 +0800, Hanjun Guo <hanjun.guo at linaro.org> wrote:
>>> ACPI 5.1 has been released and now be freely available for
>>> download [1]. It fixed some major gaps to run ACPI on ARM,
>>> this patch just follow the ACPI 5.1 spec and prepare the
>>> code to run ACPI on ARM64.
>>>
>>> ACPI 5.1 has some major changes for the following tables and
>>> method which are essential for ARM platforms:
>>> 1) MADT table updates.
>>> 2) FADT updates for PSCI
>>> 3) GTDT
>>>
>>> This patch set is the ARM64 ACPI core patches covered MADT, FADT
>>> and GTDT, platform board specific drivers are not covered by this
>>> patch set, but we provide drivers for Juno to boot with ACPI only
>>> in the follwing patch set for review purpose.
> 
> [...]
> 
>> I've read through this entire series now. In my mind, aside from a few
>> comments that I know you're addressing, this is ready.  The hooks into
>> arm64 core code are not terribly invasive, it is nicely organized and
>> manageable. Get the next version out ASAP, but I would also like to see
>> the diffs from this version to the next so I don't need to review the
>> entire series again.
>>
>> Regarding the requests to refactor ACPICA to work better for ARM. I
>> completely agree that it should be done, but I do not think it should be
>> a prerequisite to getting this core support merged. That kind of
>> refactoring is far easier to justify when it has immediate improvement
>> on the mainline codebase, and it gives us a working baseline to test
>> against. Doing it the other way around just makes things harder.
>>
>> I would really like to see the next version of this series go into
>> linux-next. I think this is ready for some wider exposure. Have you got
>> a branch being pulled into Fengguang's autobuilder yet?
> 
> Apart from build testing, what does this wider exposure achieve? Is there a
> platform available that would be able to boot Linux (to a meaingful state)
> with this patch series alone?

With this patch series, plus a couple of minor device patches (to add
the necessary OF->ACPI probe conversion, which is needed in any case) it
is possible to boot both an AMD Seattle and an APM Mustang system[0] to
a prompt. Both sets of hardware should be represented at Connect next
week. In addition, AMD will be following up with an example (similar to
the Juno one) for booting Seattle with the current patchset.

Jon.

[0] A replacement UEFI firmware is available for APM Mustang that
contains updated ACPI tables known to work with this patch series.
Mustang systems will transition over to this firmware over time. In the
case of Seattle, systems ship today with the correct UEFI/ACPI combo.