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Re: [Xen-devel] [PATCH v2 3/4] xen:arm: arm64: Add correct MPIDR_HWID_MASK value for ARM64

On 27 May 2016 at 18:50, Julien Grall <julien.grall@xxxxxxx> wrote:
> Hi Wei,
> On 26/05/16 08:58, Wei Chen wrote:
>> Currently, MPIDR_HWID_MASK is using the bit definition of AArch32 MPIDR.
>>  From ARMv8 ARM we can see there are 4 levels of affinity on AArch64
>> whilst AArch32 has only 3. So, this value is not correct when Xen is
>> running on AArch64.
>> Now, we use the value 0xff00ffffff for this macro on AArch64. But neither
>> of this value and its bitwise invert value can be used in mov instruction
>> with the encoding of {imm16:shift} or {imms:immr}. So we have to use ldr
>> to load the bitwise invert value to register.
>> The details of mov immediate encoding are listed in ARMv8 ARM C4.2.5.
> The section numbering may change between two versions of the spec. I would
> mention the version (e.g DDI 0487A.i, I guess?).

Sure, I would do it in v3.

> Regards,
> --
> Julien Grall

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