Re: [PATCH v12 05/12] PCI: OF: Fix the conversion of IO ranges into IO resources.

[Bjorn Helgaas <bhelgaas@google.com>]

On Tue, Sep 23, 2014 at 7:12 PM, Liviu Dudau <liviu@dudau.co.uk> wrote:
> On Tue, Sep 23, 2014 at 06:22:53PM -0600, Bjorn Helgaas wrote:
>> [+cc Andrew]
>>
>> On Tue, Sep 23, 2014 at 08:01:07PM +0100, Liviu Dudau wrote:
>> > The ranges property for a host bridge controller in DT describes
>> > the mapping between the PCI bus address and the CPU physical address.
>> > The resources framework however expects that the IO resources start
>> > at a pseudo "port" address 0 (zero) and have a maximum size of IO_SPACE_LIMIT.
>> > The conversion from pci ranges to resources failed to take that into account,
>> > returning a CPU physical address instead of a port number.
>> >
>> > Also fix all the drivers that depend on the old behaviour by fetching
>> > the CPU physical address based on the port number where it is being needed.
>> >
>> > Cc: Grant Likely <grant.likely@linaro.org>
>> > Cc: Rob Herring <robh+dt@kernel.org>
>> > Cc: Arnd Bergmann <arnd@arndb.de>
>> > Acked-by: Linus Walleij <linus.walleij@linaro.org>
>> > Cc: Thierry Reding <thierry.reding@gmail.com>
>> > Cc: Simon Horman <horms@verge.net.au>
>> > Cc: Catalin Marinas <catalin.marinas@arm.com>
>> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
>> > ---
>> >  arch/arm/mach-integrator/pci_v3.c | 23 ++++++++++----------
>> >  drivers/of/address.c              | 44 +++++++++++++++++++++++++++++++++++----
>> >  drivers/pci/host/pci-tegra.c      | 10 ++++++---
>> >  drivers/pci/host/pcie-rcar.c      | 21 +++++++++++++------
>> >  include/linux/of_address.h        | 15 ++++++-------
>> >  5 files changed, 82 insertions(+), 31 deletions(-)
>> > ...
>>
>> The of_pci_range_to_resource() implementation in drivers/of/address.c is
>> always compiled when CONFIG_OF_ADDRESS=y, but when CONFIG_OF_ADDRESS=y and
>> CONFIG_PCI is not set, we get the static inline version from
>> include/linux/of_address.h as well, causing a redefinition error.
>>
>> > diff --git a/drivers/of/address.c b/drivers/of/address.c
>> > @@ -957,12 +957,48 @@ bool of_dma_is_coherent(struct device_node *np)
>> > ...
>> > +int of_pci_range_to_resource(struct of_pci_range *range,
>> > +   struct device_node *np, struct resource *res)
>>
>> > diff --git a/include/linux/of_address.h b/include/linux/of_address.h
>> > ...
>> >  #else /* CONFIG_OF_ADDRESS && CONFIG_PCI */
>> >  static inline int of_pci_address_to_resource(struct device_node *dev, int bar,
>> >                                          struct resource *r)
>> > @@ -144,6 +139,12 @@ static inline int of_pci_address_to_resource(struct device_node *dev, int bar,
>> >     return -ENOSYS;
>> >  }
>> >
>> > +static inline int of_pci_range_to_resource(struct of_pci_range *range,
>> > +           struct device_node *np, struct resource *res)
>> > +{
>> > +   return -ENOSYS;
>> > +}
>>
>> My proposal to fix it is the following three patches.  The first moves the
>> inline version of of_pci_range_to_resource() into the existing "#if
>> defined(CONFIG_OF_ADDRESS) && defined(CONFIG_PCI)" block.
>>
>> Andrew added it (and some other PCI-related things) with 29b635c00f3e
>> ("of/pci: Provide support for parsing PCI DT ranges property") to
>> of_address.h outside of any ifdefs, so it's always available.  Maybe
>> there's a reason that's needed in the non-CONFIG_PCI case, but I didn't see
>> it with a quick look.
>>
>> The second moves of_pci_range_to_resource() to address.c, still inside the
>> "#ifdef CONFIG_PCI" block.
>
> Hi Bjorn,
>
> Looks good to me. Sorry for messing this up, I've tested a combination of
> CONFIG_PCI=y and CONFIG_PCI=n but it looks like I've only tested
> CONFIG_OF_ADDRESS=CONFIG_PCI (both enabled or both disabled).

You probably saw the subsequent [pci:pci/host-generic 10/13]
drivers/of/of_pci.c:202:3: error: implicit declaration of function
'of_pci_range_to_resource' error.

I looked at that a bit, but gave up.  Apparently drivers/of/of_pci.c
can be compiled with CONFIG_PCI=y but CONFIG_OF_ADDRESS not set..

Bjorn