[PATCH v2] powerpc: fsl_pci: Add forced PCI Agent enumeration
asierra at xes-inc.com
Wed Aug 27 07:12:58 EST 2014
----- Original Message -----
> From: "Scott Wood" <scottwood at freescale.com>
> Sent: Tuesday, August 26, 2014 3:52:56 PM
> On Mon, 2014-08-25 at 18:54 -0500, Aaron Sierra wrote:
> > The following commit prevents the MPC8548E on the XPedite5200 PrPMC
> > module from enumerating its PCI/PCI-X bus:
> > powerpc/fsl-pci: use 'Header Type' to identify PCIE mode
> > The previous patch prevents any Freescale PCI-X bridge from enumerating
> > the bus, if it is hardware strapped into Agent mode.
> > In PCI-X, the Host is responsible for driving the PCI-X initialization
> > pattern to devices on the bus, so that they know whether to operate in
> > conventional PCI or PCI-X mode as well as what the bus timing will be.
> > For a PCI-X PrPMC, the pattern is driven by the mezzanine carrier it is
> > installed onto. Therefore, PrPMCs are PCI-X Agents, but one per system
> > may still enumerate the bus.
> > This patch causes the device node of any PCI/PCI-X bridge strapped into
> > Agent mode to be checked for the fsl,pci-agent-force-enum property. If
> > the property is present in the node, the bridge will be allowed to
> > enumerate the bus.
> > Cc: Minghuan Lian <Minghuan.Lian at freescale.com>
> > Signed-off-by: Aaron Sierra <asierra at xes-inc.com>
> > ---
> > .../bindings/pci/fsl,pci-agent-force-enum.txt | 27
> > ++++++++++++++++++++++
> > arch/powerpc/sysdev/fsl_pci.c | 3 ++-
> > 2 files changed, 29 insertions(+), 1 deletion(-)
> > create mode 100644
> > Documentation/devicetree/bindings/pci/fsl,pci-agent-force-enum.txt
> > diff --git
> > a/Documentation/devicetree/bindings/pci/fsl,pci-agent-force-enum.txt
> > b/Documentation/devicetree/bindings/pci/fsl,pci-agent-force-enum.txt
> > new file mode 100644
> > index 0000000..d8ac4a7
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/pci/fsl,pci-agent-force-enum.txt
> This ought to be part of a general fsl,pci binding, rather than its own
> file. Unfortunately there isn't such a binding yet, but let's call this
> something like "fsl,pci.txt" anyway so that there's a place to add the
> rest of the binding to.
Ok, no problem.
> Also, CC devicetree at vger.kernel.org on all device tree patches.
> Otherwise it looks OK.
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