[PATCH v9 03/12] PCI: Introduce helper functions to deal with PCI I/O ranges.

Catalin Marinas catalin.marinas at arm.com
Mon Aug 18 07:26:04 PDT 2014


On Tue, Aug 12, 2014 at 05:25:16PM +0100, Liviu Dudau wrote:
> Some architectures do not have a simple view of the PCI I/O space
> and instead use a range of CPU addresses that map to bus addresses.
> For some architectures these ranges will be expressed by OF bindings
> in a device tree file.
> 
> This patch introduces a pci_register_io_range() helper function with
> a generic implementation that can be used by such architectures to
> keep track of the I/O ranges described by the PCI bindings. If the
> PCI_IOBASE macro is not defined that signals lack of support for PCI
> and we return an error.
> 
> In order to retrieve the CPU address associated with an I/O port, a
> new helper function pci_pio_to_address() is introduced. This will
> search in the list of ranges registered with pci_register_io_range()
> and return the CPU address that corresponds to the given port.
> 
> Cc: Grant Likely <grant.likely at linaro.org>
> Cc: Rob Herring <robh+dt at kernel.org>
> Cc: Arnd Bergmann <arnd at arndb.de>
> Signed-off-by: Liviu Dudau <Liviu.Dudau at arm.com>
> ---
>  drivers/of/address.c       | 95 ++++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/of_address.h |  2 +
>  2 files changed, 97 insertions(+)

Actually, I think we moved too much code into drivers/of/. Is there
anything OF specific about this code to live here (apart from
OF_BAD_ADDR)? I think driver/pci/ more appropriate?

Otherwise it looks fine to me.

-- 
Catalin



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