Re: [RFC PATCH] Exporting extra tables for machines without /dev/mem

Rafael J. Wysocki
2015-08-05T23:11:12Z

On Wednesday, August 05, 2015 02:25:06 PM Al Stone wrote:
> On 07/21/2015 07:31 AM, Graeme Gregory wrote:
> > Hi,
> >
> > I thought I would send this patch as an RFC. It is something I did when
> > another linaro engineer was modifying acpica-tools to not require /dev/mem.
> >
> > It exports the 3 tables that are not currenly exported in sysfs.
> >
> > Currently I do not think there is any user of this because acpica-tools can
> > can recover the information in the other tables without these three being
> > exported, fwts also works fine without the patch so the only use case I have
> > is the vague "might be useful for debug"
>
> Right -- and I personally would like to have that debug use case. AFAICT,
> the RSDP and RSDT/XSDT are recreated by acpidump; i.e., based on knowledge
> of the mapped tables, acpidump builds what it believes these tables should
> look like. But, the /dev/mem mappings would give me what ACPI is actually
> using (what was directly passed to the kernel). Should there be a bug in
> table mapping or ACPI startup, this info might help.

If my memory serves me right, Lv has been doing something in that area. Lv?