diff mbox

[v9,12/12] PCI: Introduce pci_remap_iospace() for remapping PCI I/O bus resources into CPU space

Message ID 1407860725-25202-13-git-send-email-Liviu.Dudau@arm.com (mailing list archive)
State New, archived
Delegated to: Bjorn Helgaas
Headers show

Commit Message

Liviu Dudau Aug. 12, 2014, 4:25 p.m. UTC
Introduce a default implementation for remapping PCI bus I/O resources
onto the CPU address space. Architectures with special needs may
provide their own version, but most should be able to use this one.

Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
---
 drivers/pci/pci.c   | 33 +++++++++++++++++++++++++++++++++
 include/linux/pci.h |  3 +++
 2 files changed, 36 insertions(+)

Comments

Catalin Marinas Aug. 13, 2014, 10:01 a.m. UTC | #1
On Tue, Aug 12, 2014 at 05:25:25PM +0100, Liviu Dudau wrote:
> Introduce a default implementation for remapping PCI bus I/O resources
> onto the CPU address space. Architectures with special needs may
> provide their own version, but most should be able to use this one.
> 
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Rob Herring <robh+dt@kernel.org>
> Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>

I guess you could have added the generic pgprot_device definition to
this patch and the arm64 specific one in the separate arm64 PCIe support
(and one less patch in total). But not a big issue either way.
Liviu Dudau Aug. 13, 2014, 10:33 a.m. UTC | #2
On Wed, Aug 13, 2014 at 11:01:18AM +0100, Catalin Marinas wrote:
> On Tue, Aug 12, 2014 at 05:25:25PM +0100, Liviu Dudau wrote:
> > Introduce a default implementation for remapping PCI bus I/O resources
> > onto the CPU address space. Architectures with special needs may
> > provide their own version, but most should be able to use this one.
> > 
> > Cc: Bjorn Helgaas <bhelgaas@google.com>
> > Cc: Arnd Bergmann <arnd@arndb.de>
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
> 
> I guess you could have added the generic pgprot_device definition to
> this patch and the arm64 specific one in the separate arm64 PCIe support
> (and one less patch in total). But not a big issue either way.

I went by the established history on that file, where a new interface gets
introduced together with its use. I guess it makes backing out the change
much easier?

Best regards,
Liviu

> 
> -- 
> Catalin
Catalin Marinas Aug. 13, 2014, 10:53 a.m. UTC | #3
On Wed, Aug 13, 2014 at 11:33:11AM +0100, Liviu Dudau wrote:
> On Wed, Aug 13, 2014 at 11:01:18AM +0100, Catalin Marinas wrote:
> > On Tue, Aug 12, 2014 at 05:25:25PM +0100, Liviu Dudau wrote:
> > > Introduce a default implementation for remapping PCI bus I/O resources
> > > onto the CPU address space. Architectures with special needs may
> > > provide their own version, but most should be able to use this one.
> > > 
> > > Cc: Bjorn Helgaas <bhelgaas@google.com>
> > > Cc: Arnd Bergmann <arnd@arndb.de>
> > > Cc: Rob Herring <robh+dt@kernel.org>
> > > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
> > 
> > I guess you could have added the generic pgprot_device definition to
> > this patch and the arm64 specific one in the separate arm64 PCIe support
> > (and one less patch in total). But not a big issue either way.
> 
> I went by the established history on that file, where a new interface gets
> introduced together with its use. I guess it makes backing out the change
> much easier?

The point is that the only user of pgprot_device is pci_remap_iospace()
currently, so it makes sense to introduce the generic definition
together with this patch.
Rob Herring Aug. 22, 2014, 4:16 a.m. UTC | #4
On Tue, Aug 12, 2014 at 11:25 AM, Liviu Dudau <Liviu.Dudau@arm.com> wrote:
> Introduce a default implementation for remapping PCI bus I/O resources
> onto the CPU address space. Architectures with special needs may
> provide their own version, but most should be able to use this one.
>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Rob Herring <robh+dt@kernel.org>
> Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>

Reviewed-by: Rob Herring <robh@kernel.org>

However, I would like to see ARM pci_ioremap_io converted over to this function.

Rob

> ---
>  drivers/pci/pci.c   | 33 +++++++++++++++++++++++++++++++++
>  include/linux/pci.h |  3 +++
>  2 files changed, 36 insertions(+)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 29d1775..76d21b6 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -2707,6 +2707,39 @@ int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
>  }
>  EXPORT_SYMBOL(pci_request_regions_exclusive);
>
> +/**
> + *     pci_remap_iospace - Remap the memory mapped I/O space
> + *     @res: Resource describing the I/O space
> + *     @phys_addr: physical address where the range will be mapped.
> + *
> + *     Remap the memory mapped I/O space described by the @res
> + *     into the CPU physical address space. Only architectures
> + *     that have memory mapped IO defined (and hence PCI_IOBASE)
> + *     should call this function.
> + */
> +int __weak pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
> +{
> +       int err = -ENODEV;
> +
> +#ifdef PCI_IOBASE
> +       if (!(res->flags & IORESOURCE_IO))
> +               return -EINVAL;
> +
> +       if (res->end > IO_SPACE_LIMIT)
> +               return -EINVAL;
> +
> +       err = ioremap_page_range(res->start + (unsigned long)PCI_IOBASE,
> +                               res->end + 1 + (unsigned long)PCI_IOBASE,
> +                               phys_addr, pgprot_device(PAGE_KERNEL));
> +#else
> +       /* this architecture does not have memory mapped I/O space,
> +          so this function should never be called */
> +       WARN_ON(1);
> +#endif
> +
> +       return err;
> +}
> +
>  static void __pci_set_master(struct pci_dev *dev, bool enable)
>  {
>         u16 old_cmd, cmd;
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index e1e0d80..988c2f5 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1098,6 +1098,9 @@ int __must_check pci_bus_alloc_resource(struct pci_bus *bus,
>                                                   resource_size_t),
>                         void *alignf_data);
>
> +
> +int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);
> +
>  static inline dma_addr_t pci_bus_address(struct pci_dev *pdev, int bar)
>  {
>         struct pci_bus_region region;
> --
> 2.0.4
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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Liviu Dudau Aug. 22, 2014, 12:43 p.m. UTC | #5
On Thu, Aug 21, 2014 at 11:16:16PM -0500, Rob Herring wrote:
> On Tue, Aug 12, 2014 at 11:25 AM, Liviu Dudau <Liviu.Dudau@arm.com> wrote:
> > Introduce a default implementation for remapping PCI bus I/O resources
> > onto the CPU address space. Architectures with special needs may
> > provide their own version, but most should be able to use this one.
> >
> > Cc: Bjorn Helgaas <bhelgaas@google.com>
> > Cc: Arnd Bergmann <arnd@arndb.de>
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
> 
> Reviewed-by: Rob Herring <robh@kernel.org>

Thanks, Rob, much appreciated!

> 
> However, I would like to see ARM pci_ioremap_io converted over to this function.

Do you care if this is done as a separate patch?

Best regards,
Liviu

> 
> Rob
> 
> > ---
> >  drivers/pci/pci.c   | 33 +++++++++++++++++++++++++++++++++
> >  include/linux/pci.h |  3 +++
> >  2 files changed, 36 insertions(+)
> >
> > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> > index 29d1775..76d21b6 100644
> > --- a/drivers/pci/pci.c
> > +++ b/drivers/pci/pci.c
> > @@ -2707,6 +2707,39 @@ int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
> >  }
> >  EXPORT_SYMBOL(pci_request_regions_exclusive);
> >
> > +/**
> > + *     pci_remap_iospace - Remap the memory mapped I/O space
> > + *     @res: Resource describing the I/O space
> > + *     @phys_addr: physical address where the range will be mapped.
> > + *
> > + *     Remap the memory mapped I/O space described by the @res
> > + *     into the CPU physical address space. Only architectures
> > + *     that have memory mapped IO defined (and hence PCI_IOBASE)
> > + *     should call this function.
> > + */
> > +int __weak pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
> > +{
> > +       int err = -ENODEV;
> > +
> > +#ifdef PCI_IOBASE
> > +       if (!(res->flags & IORESOURCE_IO))
> > +               return -EINVAL;
> > +
> > +       if (res->end > IO_SPACE_LIMIT)
> > +               return -EINVAL;
> > +
> > +       err = ioremap_page_range(res->start + (unsigned long)PCI_IOBASE,
> > +                               res->end + 1 + (unsigned long)PCI_IOBASE,
> > +                               phys_addr, pgprot_device(PAGE_KERNEL));
> > +#else
> > +       /* this architecture does not have memory mapped I/O space,
> > +          so this function should never be called */
> > +       WARN_ON(1);
> > +#endif
> > +
> > +       return err;
> > +}
> > +
> >  static void __pci_set_master(struct pci_dev *dev, bool enable)
> >  {
> >         u16 old_cmd, cmd;
> > diff --git a/include/linux/pci.h b/include/linux/pci.h
> > index e1e0d80..988c2f5 100644
> > --- a/include/linux/pci.h
> > +++ b/include/linux/pci.h
> > @@ -1098,6 +1098,9 @@ int __must_check pci_bus_alloc_resource(struct pci_bus *bus,
> >                                                   resource_size_t),
> >                         void *alignf_data);
> >
> > +
> > +int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);
> > +
> >  static inline dma_addr_t pci_bus_address(struct pci_dev *pdev, int bar)
> >  {
> >         struct pci_bus_region region;
> > --
> > 2.0.4
> >
> >
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> --
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>
Rob Herring Aug. 23, 2014, 4:57 p.m. UTC | #6
On Fri, Aug 22, 2014 at 7:43 AM, Liviu Dudau <liviu@dudau.co.uk> wrote:
> On Thu, Aug 21, 2014 at 11:16:16PM -0500, Rob Herring wrote:
>> On Tue, Aug 12, 2014 at 11:25 AM, Liviu Dudau <Liviu.Dudau@arm.com> wrote:
>> > Introduce a default implementation for remapping PCI bus I/O resources
>> > onto the CPU address space. Architectures with special needs may
>> > provide their own version, but most should be able to use this one.
>> >
>> > Cc: Bjorn Helgaas <bhelgaas@google.com>
>> > Cc: Arnd Bergmann <arnd@arndb.de>
>> > Cc: Rob Herring <robh+dt@kernel.org>
>> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
>>
>> Reviewed-by: Rob Herring <robh@kernel.org>
>
> Thanks, Rob, much appreciated!
>
>>
>> However, I would like to see ARM pci_ioremap_io converted over to this function.
>
> Do you care if this is done as a separate patch?

Yes, that's fine hence the reviewed-by.

Rob
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diff mbox

Patch

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 29d1775..76d21b6 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2707,6 +2707,39 @@  int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
 }
 EXPORT_SYMBOL(pci_request_regions_exclusive);
 
+/**
+ *	pci_remap_iospace - Remap the memory mapped I/O space
+ *	@res: Resource describing the I/O space
+ *	@phys_addr: physical address where the range will be mapped.
+ *
+ *	Remap the memory mapped I/O space described by the @res
+ *	into the CPU physical address space. Only architectures
+ *	that have memory mapped IO defined (and hence PCI_IOBASE)
+ *	should call this function.
+ */
+int __weak pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
+{
+	int err = -ENODEV;
+
+#ifdef PCI_IOBASE
+	if (!(res->flags & IORESOURCE_IO))
+		return -EINVAL;
+
+	if (res->end > IO_SPACE_LIMIT)
+		return -EINVAL;
+
+	err = ioremap_page_range(res->start + (unsigned long)PCI_IOBASE,
+				res->end + 1 + (unsigned long)PCI_IOBASE,
+				phys_addr, pgprot_device(PAGE_KERNEL));
+#else
+	/* this architecture does not have memory mapped I/O space,
+	   so this function should never be called */
+	WARN_ON(1);
+#endif
+
+	return err;
+}
+
 static void __pci_set_master(struct pci_dev *dev, bool enable)
 {
 	u16 old_cmd, cmd;
diff --git a/include/linux/pci.h b/include/linux/pci.h
index e1e0d80..988c2f5 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1098,6 +1098,9 @@  int __must_check pci_bus_alloc_resource(struct pci_bus *bus,
 						  resource_size_t),
 			void *alignf_data);
 
+
+int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);
+
 static inline dma_addr_t pci_bus_address(struct pci_dev *pdev, int bar)
 {
 	struct pci_bus_region region;