Re: [PATCH v11 08/10] OF: PCI: Add support for parsing PCI host bridge resources from DT

From: Robert Richter
Date: Mon Sep 22 2014 - 08:16:03 EST


On 22.09.14 12:43:17, Liviu Dudau wrote:
> On Mon, Sep 22, 2014 at 10:32:28AM +0100, Robert Richter wrote:
> > On 18.09.14 02:30:23, Liviu Dudau wrote:
> > > +int of_pci_get_host_bridge_resources(struct device_node *dev,
> > > + unsigned char busno, unsigned char bus_max,
> > > + struct list_head *resources, resource_size_t *io_base)
> > > +{
> > > + struct resource *res;
> > > + struct resource *bus_range;
> > > + struct of_pci_range range;
> > > + struct of_pci_range_parser parser;
> > > + char range_type[4];
> > > + int err;
> > > +
> > > + if (!io_base)
> > > + return -EINVAL;
> > > + *io_base = OF_BAD_ADDR;
> >
>
> Hi Robert,
>
> > This breaks for mem-mapped pci host controllers. The patch below fixes
> > this.
>
> I think you mean PCI host controller that have only memory mapped ranges,
> am I right? Initially I've read your reply as to mean that the host
> controller is accessed through some memory mapped area, which I believe is
> the case for all host controllers.

Right, that's meant here. Sorry for the misleading comment.

>
> >
> > This series was tested with the fix on top for Cavium Thunder.
> >
> > Tested-by: Robert Richter <rrichter@xxxxxxxxxx>
>
> Thanks for that!
>
> >
> > -Robert
> >
> >
> >
> > From e798af4fc2f664d1aff7e863489b8298f90e716e Mon Sep 17 00:00:00 2001
> > From: Robert Richter <rrichter@xxxxxxxxxx>
> > Date: Mon, 22 Sep 2014 10:46:01 +0200
> > Subject: [PATCH] OF: PCI: Fix creation of mem-mapped pci host bridges
> >
> > The pci host bridge was not created if io_base was not set when
> > calling of_pci_get_host_bridge_resources(). This is esp. the case for
> > mem-mapped io (IORESOURCE_MEM). This patch fixes this. Function
> > parameter io_base is optional now.
>
> I think the message is misleading. What you want to do is make io_base
> optional for the case where the PCI host bridge only expects to have only
> IORESOURCE_MEM ranges and doesn't care about IORESOURCE_IO ones.
>
> As I'm going to touch this area again to address a comment from Bjorn,
> do you mind if I roll this patch into mine with your Signed-off-by and
> the mention that you have made io_base optional?

Sure, fine with me.

Thanks,

-Robert


>
> Best regards,
> Liviu
>
> >
> > Signed-off-by: Robert Richter <rrichter@xxxxxxxxxx>
> > ---
> > drivers/of/of_pci.c | 7 +++----
> > 1 file changed, 3 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
> > index ffdb45ed8682..1f0e7c2505ee 100644
> > --- a/drivers/of/of_pci.c
> > +++ b/drivers/of/of_pci.c
> > @@ -182,9 +182,8 @@ int of_pci_get_host_bridge_resources(struct device_node *dev,
> > char range_type[4];
> > int err;
> >
> > - if (!io_base)
> > - return -EINVAL;
> > - *io_base = OF_BAD_ADDR;
> > + if (io_base)
> > + *io_base = OF_BAD_ADDR;
> >
> > bus_range = kzalloc(sizeof(*bus_range), GFP_KERNEL);
> > if (!bus_range)
> > @@ -242,7 +241,7 @@ int of_pci_get_host_bridge_resources(struct device_node *dev,
> > goto parse_failed;
> > }
> >
> > - if (resource_type(res) == IORESOURCE_IO) {
> > + if (io_base && resource_type(res) == IORESOURCE_IO) {
> > if (*io_base != OF_BAD_ADDR)
> > pr_warn("More than one I/O resource converted. CPU offset for old range lost!\n");
> > *io_base = range.cpu_addr;
> > --
> > 2.1.0
> >
> > --
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> >
>
> --
> ====================
> | I would like to |
> | fix the world, |
> | but they're not |
> | giving me the |
> \ source code! /
> ---------------
> Â\_(ã)_/Â
>
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