Message-ID: <1433167169.13900.140.camel@linux.intel.com>
Subject: Re: [PATCH 5/5] pcmcia: add a new resource manager for non ISA
 systems
From: Alan Cox <alan@linux.intel.com>
To: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: linux-kernel@vger.kernel.org, linux-pcmica@lists.infradead.org
Date: Mon, 01 Jun 2015 14:59:29 +0100
In-Reply-To: <20150530144055.GA10043@light.dominikbrodowski.net>
References: <20141204213108.1351.2478.stgit@localhost.localdomain>
	 <20150530144055.GA10043@light.dominikbrodowski.net>
Organization: Intel Corporation
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On Sat, 2015-05-30 at 16:40 +0200, Dominik Brodowski wrote:
> Alan,
> 
> On Thu, Dec 04, 2014 at 09:31:22PM +0000, Alan Cox wrote:
> > On a pure PCI platform we don't actually need all the complexity of the
> > rsrc_nonstatic manager, in fact we can just work directly with the pci
> > allocators and avoid all the complexity (and code bloat).
> 
> I know you're re-working this thing by now, but still:

It's on the todo list to finish debugging

> Can we be certain that BIOS, ACPI etc. properly report all io resources
> which must not be utilized by other devices? Does this really depend on ISA

No you can't. However there appears to be a convention that for mmio the
windows are aligned on largish boundaries and vendors only hide hardware
so that it's next to existing resources on an alignment such that it
won't get allocated.

I've no idea if it's in a spec anywhere or that's just a "Hey it works
in Windows" bit of history.

> being set in Kconfig? Should this also be enabled for CardBus bridges on the
> root PCI bus? And: could doing a check for X86 like in rsrc_nonstatic.c
> ( avoid anything < 0x100 for ioports ) help to avoid some of the possible
> fallout?

Probably yes.

Added to the TODO list for it.

Alan


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