ARM bigendian cpuhotplug

ARM bigendian cpuhotplug

[Hemanth Kumar]

>Are you referring to ARM Vexpress platform with TC2/CA15_A7 card ?
>If yes, idle doesn't work with CONFIG_MTD_CFI irrespective of
>endianness, it's platform limitation.

>Regards,
>Sudeep


Thanks for the reply what is the hardware limitation for this card (VE
CA-15_A7) when we enable CONFIG_MTD_CFI

Reagards,
Hemanth

ARM bigendian cpuhotplug

[Sudeep Holla]

On 10/09/14 13:59, Hemanth Kumar wrote:
>> Are you referring to ARM Vexpress platform with TC2/CA15_A7 card ?
>> If yes, idle doesn't work with CONFIG_MTD_CFI irrespective of
>> endianness, it's platform limitation.
>
>> Regards,
>> Sudeep
>
>
> Thanks for the reply what is the hardware limitation for this card (VE
> CA-15_A7) when we enable CONFIG_MTD_CFI
>

The cpu resume path should ideal be on some sram or on-chip memory, but
on TC2 we use the NOR flash @0x0. When you enable NOR flash in Linux,
you can't expect it to be in read-mode always as other cpus might put
the NOR device is any mode based on its interaction. As a result when a
suspended cpu resumes it might not find the resume code if NOR was not
in read mode resulting in unpredicted behaviour. As I said before it's
purely a platform firmware limitation.

Regards,
Sudeep