[PATCH v7 07/17] ARM64 / ACPI: Disable ACPI if FADT revision is less than 5.1

Hanjun Guo hanjun.guo at linaro.org
Sat Jan 17 21:49:50 PST 2015


On 2015年01月16日 22:33, Lorenzo Pieralisi wrote:
> On Wed, Jan 14, 2015 at 03:04:55PM +0000, Hanjun Guo wrote:
>> FADT Major.Minor version was introduced in ACPI 5.1, it is the same
>> as ACPI version.
>>
>> In ACPI 5.1, some major gaps are fixed for ARM, such as updates in
>> MADT table for GIC and SMP init, without those updates, we can not
>> get the MPIDR for SMP init, and GICv2/3 related init information, so
>> we can't boot arm64 ACPI properly with table versions predating 5.1.
>>
>> If firmware provides ACPI tables with ACPI version less than 5.1,
>> OS will be messed up with those information and have no way to init
>
> Nit: "that information"
>
> or
>
> "...OS has no way to retrieve the configuration data that is necessary
> to init SMP boot protocol and the GIC properly, so.."
>
>> smp and GIC, so disable ACPI if we get an FADT table with version
>> less that 5.1.
>>
>
> Patch should be reordered in the series and must be sequenced before
> patch 5 for bisectability (that patch implements DT unflattening if ACPI
> is disabled), or squashed with previous patches.

OK, I will reorder this patch set and update the change log above.

Thanks
Hanjun



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