RE: [RFC PATCH v3 3/3] PCI/ACPI: hisi: Add ACPI support for HiSilicon SoCs Host Controllers

[Gabriele Paoloni <gabriele.paoloni@huawei.com>]

> -----Original Message-----
> From: linux-kernel-owner@vger.kernel.org [mailto:linux-kernel-
> owner@vger.kernel.org] On Behalf Of Mark Rutland
> Sent: 10 February 2016 11:13
> To: Gabriele Paoloni
> Cc: Guohanjun (Hanjun Guo); Wangzhou (B); liudongdong (C); Linuxarm;
> qiujiang; bhelgaas@google.com; arnd@arndb.de;
> Lorenzo.Pieralisi@arm.com; tn@semihalf.com; linux-pci@vger.kernel.org;
> linux-kernel@vger.kernel.org; xuwei (O); linux-acpi@vger.kernel.org;
> jcm@redhat.com; zhangjukuo; Liguozhu (Kenneth); linux-arm-
> kernel@lists.infradead.org
> Subject: Re: [RFC PATCH v3 3/3] PCI/ACPI: hisi: Add ACPI support for
> HiSilicon SoCs Host Controllers
> 
> On Wed, Feb 10, 2016 at 09:52:36AM +0000, Gabriele Paoloni wrote:
> > Hi Mark
> >
> > > On Tue, Feb 09, 2016 at 05:34:20PM +0000, Gabriele Paoloni wrote:
> > > > From: gabriele paoloni <gabriele.paoloni@huawei.com>
> > > > +/*
> > > > + * Retrieve rc_dbi base and size from _DSD
> > > > + * Name (_DSD, Package () {
> > > > + *	ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
> > > > + *	Package () {
> > > > + *	Package () {"rc-dbi", Package () { 0x0, 0xb0080000, 0x0,
> 0x10000
> > > }},
> > > > + *	}
> > > > + *	})
> > > > + */
> > >
> > > As above, this does not look right. ACPI has standard mechanisms
> for
> > > describing addresses. Making something up like this is not a good
> idea.
> >
> > I am quite new to ACPI, may I ask you to explain a bit?
> 
> ACPI has standard mechanisms for describing certain resources, and
> these
> should not be described in _DSD. Memory or IO address regions are such
> resources (in _CRS, IIRC), and should not be described in _DSD.

Hi Mark,

In my case I think in need to look into the MCFG object as the problem
I have is RC using a different range than the rest of the hierarchy.

I'll investigate this and try to come with a solution in v4

Many Thanks

Gab 

> 
> Thanks,
> Mark.