RE: [RFC][PATCH]ACPI,APEI,ERST, back end driver for NVRAM

From: Huang Ying
Date: Sun Nov 20 2011 - 19:44:40 EST


On Sat, 2011-11-19 at 07:04 +0800, Seiji Aguchi wrote:
> Hi,
>
> >According to ACPI 4.0a spec:
> >
> >"""
> >17.5.2.4.1 Error Log Address Range Resides in NVRAM
> >
>
> Thank you for giving me the information.
> Let me clarify one thing.
>
> If the busy bit can be cleared immediately, we don't need to
> check busy bit with CHECK_BUSY_STATUS.
> So, we should simply execute OSPM operations as follows.
>
> - Writing
> 1. BEGIN_WRITE
> 2. SET_RECORD_OFFSET
> 3. EXECUTE_OPERATION
> 4. END
>
> - Reading
> 1. BEGIN_READ
> 2. SET_RECORD_OFFSET
> 3. SET_RECORD_ID
> 4. EXECUTE_OPERATION
> (END operation is not needed because OSPM requires no platform
> support to read.)
>
> - Clearing
> 1. BEGIN_CLEAR
> 2. SET_RECORD_ID
> 3. EXECUTE_OPERATION
> (END operation is not needed because OSPM requires no platform
> support to clear.)
>
> Is this what you expected?

No. I have different understanding.

Because error log address range resides in NVRAM, the contents will be
reserved even after reboot. So we do not need read/clear operations at
all, and should place all records in error log address range.

Best Regards,
Huang Ying


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