[v12,09/12] OF: PCI: Add support for parsing PCI host bridge resources from DT

Commit Message

Liviu Dudau Sept. 24, 2014, 4:43 p.m. UTC

Provide a function to parse the PCI DT ranges that can be used to
create a pci_host_bridge structure together with its associated
bus.

Cc: Bjorn Helgaas <[e-mail]>
Cc: Arnd Bergmann <[e-mail]>
Cc: Grant Likely <[e-mail]>
Cc: Rob Herring <[e-mail]>
Cc: Catalin Marinas <[e-mail]>
Signed-off-by: Liviu Dudau <[e-mail]>
[make io_base parameter optional]
Signed-off-by: Robert Richter <[e-mail]>
---
Hi Bjorn,

I have fixed the compilation error that this patch was triggering. I
have validated that the patch applies to your pci/host-generic branch
as well as to my series.

Best regards,
Liviu


 drivers/of/of_pci.c    | 117 +++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/of_pci.h |   6 +++
 2 files changed, 123 insertions(+)

Comments

Bjorn Helgaas Sept. 24, 2014, 5:31 p.m. UTC | #1

On Wed, Sep 24, 2014 at 05:43:04PM +0100, Liviu Dudau wrote:
> Provide a function to parse the PCI DT ranges that can be used to
> create a pci_host_bridge structure together with its associated
> bus.
> 
> Cc: Bjorn Helgaas <[e-mail]>
> Cc: Arnd Bergmann <[e-mail]>
> Cc: Grant Likely <[e-mail]>
> Cc: Rob Herring <[e-mail]>
> Cc: Catalin Marinas <[e-mail]>
> Signed-off-by: Liviu Dudau <[e-mail]>
> [make io_base parameter optional]
> Signed-off-by: Robert Richter <[e-mail]>
> ---
> Hi Bjorn,
> 
> I have fixed the compilation error that this patch was triggering. I
> have validated that the patch applies to your pci/host-generic branch
> as well as to my series.

I applied this to pci/host-generic along with the following patches and
pushed the branch, thanks!

Bjorn

>  drivers/of/of_pci.c    | 117 +++++++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/of_pci.h |   6 +++
>  2 files changed, 123 insertions(+)
> 
> diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
> index 82d172f..3cad1af 100644
> --- a/drivers/of/of_pci.c
> +++ b/drivers/of/of_pci.c
> @@ -1,7 +1,9 @@
>  #include <linux/kernel.h>
>  #include <linux/export.h>
>  #include <linux/of.h>
> +#include <linux/of_address.h>
>  #include <linux/of_pci.h>
> +#include <linux/slab.h>
>  
>  static inline int __of_pci_pci_compare(struct device_node *node,
>  				       unsigned int data)
> @@ -114,6 +116,121 @@ int of_get_pci_domain_nr(struct device_node *node)
>  }
>  EXPORT_SYMBOL_GPL(of_get_pci_domain_nr);
>  
> +#if defined(CONFIG_OF_ADDRESS)
> +/**
> + * of_pci_get_host_bridge_resources - Parse PCI host bridge resources from DT
> + * @dev: device node of the host bridge having the range property
> + * @busno: bus number associated with the bridge root bus
> + * @bus_max: maximum number of busses for this bridge
> + * @resources: list where the range of resources will be added after DT parsing
> + * @io_base: pointer to a variable that will contain on return the physical
> + * address for the start of the I/O range. Can be NULL if the caller doesn't
> + * expect IO ranges to be present in the device tree.
> + *
> + * It is the callers job to free the @resources list.
> + *
> + * This function will parse the "ranges" property of a PCI host bridge device
> + * node and setup the resource mapping based on its content. It is expected
> + * that the property conforms with the Power ePAPR document.
> + *
> + * It returns zero if the range parsing has been successful or a standard error
> + * value if it failed.
> + */
> +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)
> +		*io_base = (resource_size_t)OF_BAD_ADDR;
> +
> +	bus_range = kzalloc(sizeof(*bus_range), GFP_KERNEL);
> +	if (!bus_range)
> +		return -ENOMEM;
> +
> +	pr_info("PCI host bridge %s ranges:\n", dev->full_name);
> +
> +	err = of_pci_parse_bus_range(dev, bus_range);
> +	if (err) {
> +		bus_range->start = busno;
> +		bus_range->end = bus_max;
> +		bus_range->flags = IORESOURCE_BUS;
> +		pr_info("  No bus range found for %s, using %pR\n",
> +			dev->full_name, bus_range);
> +	} else {
> +		if (bus_range->end > bus_range->start + bus_max)
> +			bus_range->end = bus_range->start + bus_max;
> +	}
> +	pci_add_resource(resources, bus_range);
> +
> +	/* Check for ranges property */
> +	err = of_pci_range_parser_init(&parser, dev);
> +	if (err)
> +		goto parse_failed;
> +
> +	pr_debug("Parsing ranges property...\n");
> +	for_each_of_pci_range(&parser, &range) {
> +		/* Read next ranges element */
> +		if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_IO)
> +			snprintf(range_type, 4, " IO");
> +		else if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM)
> +			snprintf(range_type, 4, "MEM");
> +		else
> +			snprintf(range_type, 4, "err");
> +		pr_info("  %s %#010llx..%#010llx -> %#010llx\n", range_type,
> +			range.cpu_addr, range.cpu_addr + range.size - 1,
> +			range.pci_addr);
> +
> +		/*
> +		 * If we failed translation or got a zero-sized region
> +		 * then skip this range
> +		 */
> +		if (range.cpu_addr == OF_BAD_ADDR || range.size == 0)
> +			continue;
> +
> +		res = kzalloc(sizeof(struct resource), GFP_KERNEL);
> +		if (!res) {
> +			err = -ENOMEM;
> +			goto parse_failed;
> +		}
> +
> +		err = of_pci_range_to_resource(&range, dev, res);
> +		if (err)
> +			goto conversion_failed;
> +
> +		if (resource_type(res) == IORESOURCE_IO) {
> +			if (!io_base) {
> +				pr_err("I/O range found for %s. Please provide an io_base pointer to save CPU base address\n",
> +					dev->full_name);
> +				err = -EINVAL;
> +				goto conversion_failed;
> +			}
> +			if (*io_base != (resource_size_t)OF_BAD_ADDR)
> +				pr_warn("More than one I/O resource converted for %s. CPU base address for old range lost!\n",
> +					dev->full_name);
> +			*io_base = range.cpu_addr;
> +		}
> +
> +		pci_add_resource_offset(resources, res,	res->start - range.pci_addr);
> +	}
> +
> +	return 0;
> +
> +conversion_failed:
> +	kfree(res);
> +parse_failed:
> +	pci_free_resource_list(resources);
> +	return err;
> +}
> +EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources);
> +#endif /* CONFIG_OF_ADDRESS */
> +
>  #ifdef CONFIG_PCI_MSI
>  
>  static LIST_HEAD(of_pci_msi_chip_list);
> diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
> index 71062e9..1fd207e 100644
> --- a/include/linux/of_pci.h
> +++ b/include/linux/of_pci.h
> @@ -52,6 +52,12 @@ of_get_pci_domain_nr(struct device_node *node)
>  }
>  #endif
>  
> +#if defined(CONFIG_OF_ADDRESS)
> +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);
> +#endif
> +
>  #if defined(CONFIG_OF) && defined(CONFIG_PCI_MSI)
>  int of_pci_msi_chip_add(struct msi_chip *chip);
>  void of_pci_msi_chip_remove(struct msi_chip *chip);
> -- 
> 2.1.0
> 
> 
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Liviu Dudau Sept. 24, 2014, 5:53 p.m. UTC | #2

On Wed, Sep 24, 2014 at 06:31:09PM +0100, Bjorn Helgaas wrote:
> On Wed, Sep 24, 2014 at 05:43:04PM +0100, Liviu Dudau wrote:
> > Provide a function to parse the PCI DT ranges that can be used to
> > create a pci_host_bridge structure together with its associated
> > bus.
> > 
> > Cc: Bjorn Helgaas <[e-mail]>
> > Cc: Arnd Bergmann <[e-mail]>
> > Cc: Grant Likely <[e-mail]>
> > Cc: Rob Herring <[e-mail]>
> > Cc: Catalin Marinas <[e-mail]>
> > Signed-off-by: Liviu Dudau <[e-mail]>
> > [make io_base parameter optional]
> > Signed-off-by: Robert Richter <[e-mail]>
> > ---
> > Hi Bjorn,
> > 
> > I have fixed the compilation error that this patch was triggering. I
> > have validated that the patch applies to your pci/host-generic branch
> > as well as to my series.
> 
> I applied this to pci/host-generic along with the following patches and
> pushed the branch, thanks!

Thanks again and sorry for lack of thorough testing. I still haven't managed
to get a cross compiler for sparc and as I don't run Ubuntu or debian the
make.cross script doesn't work for me.

Best regards,
Liviu

> 
> Bjorn
> 
> >  drivers/of/of_pci.c    | 117 +++++++++++++++++++++++++++++++++++++++++++++++++
> >  include/linux/of_pci.h |   6 +++
> >  2 files changed, 123 insertions(+)
> > 
> > diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
> > index 82d172f..3cad1af 100644
> > --- a/drivers/of/of_pci.c
> > +++ b/drivers/of/of_pci.c
> > @@ -1,7 +1,9 @@
> >  #include <linux/kernel.h>
> >  #include <linux/export.h>
> >  #include <linux/of.h>
> > +#include <linux/of_address.h>
> >  #include <linux/of_pci.h>
> > +#include <linux/slab.h>
> >  
> >  static inline int __of_pci_pci_compare(struct device_node *node,
> >  				       unsigned int data)
> > @@ -114,6 +116,121 @@ int of_get_pci_domain_nr(struct device_node *node)
> >  }
> >  EXPORT_SYMBOL_GPL(of_get_pci_domain_nr);
> >  
> > +#if defined(CONFIG_OF_ADDRESS)
> > +/**
> > + * of_pci_get_host_bridge_resources - Parse PCI host bridge resources from DT
> > + * @dev: device node of the host bridge having the range property
> > + * @busno: bus number associated with the bridge root bus
> > + * @bus_max: maximum number of busses for this bridge
> > + * @resources: list where the range of resources will be added after DT parsing
> > + * @io_base: pointer to a variable that will contain on return the physical
> > + * address for the start of the I/O range. Can be NULL if the caller doesn't
> > + * expect IO ranges to be present in the device tree.
> > + *
> > + * It is the callers job to free the @resources list.
> > + *
> > + * This function will parse the "ranges" property of a PCI host bridge device
> > + * node and setup the resource mapping based on its content. It is expected
> > + * that the property conforms with the Power ePAPR document.
> > + *
> > + * It returns zero if the range parsing has been successful or a standard error
> > + * value if it failed.
> > + */
> > +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)
> > +		*io_base = (resource_size_t)OF_BAD_ADDR;
> > +
> > +	bus_range = kzalloc(sizeof(*bus_range), GFP_KERNEL);
> > +	if (!bus_range)
> > +		return -ENOMEM;
> > +
> > +	pr_info("PCI host bridge %s ranges:\n", dev->full_name);
> > +
> > +	err = of_pci_parse_bus_range(dev, bus_range);
> > +	if (err) {
> > +		bus_range->start = busno;
> > +		bus_range->end = bus_max;
> > +		bus_range->flags = IORESOURCE_BUS;
> > +		pr_info("  No bus range found for %s, using %pR\n",
> > +			dev->full_name, bus_range);
> > +	} else {
> > +		if (bus_range->end > bus_range->start + bus_max)
> > +			bus_range->end = bus_range->start + bus_max;
> > +	}
> > +	pci_add_resource(resources, bus_range);
> > +
> > +	/* Check for ranges property */
> > +	err = of_pci_range_parser_init(&parser, dev);
> > +	if (err)
> > +		goto parse_failed;
> > +
> > +	pr_debug("Parsing ranges property...\n");
> > +	for_each_of_pci_range(&parser, &range) {
> > +		/* Read next ranges element */
> > +		if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_IO)
> > +			snprintf(range_type, 4, " IO");
> > +		else if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM)
> > +			snprintf(range_type, 4, "MEM");
> > +		else
> > +			snprintf(range_type, 4, "err");
> > +		pr_info("  %s %#010llx..%#010llx -> %#010llx\n", range_type,
> > +			range.cpu_addr, range.cpu_addr + range.size - 1,
> > +			range.pci_addr);
> > +
> > +		/*
> > +		 * If we failed translation or got a zero-sized region
> > +		 * then skip this range
> > +		 */
> > +		if (range.cpu_addr == OF_BAD_ADDR || range.size == 0)
> > +			continue;
> > +
> > +		res = kzalloc(sizeof(struct resource), GFP_KERNEL);
> > +		if (!res) {
> > +			err = -ENOMEM;
> > +			goto parse_failed;
> > +		}
> > +
> > +		err = of_pci_range_to_resource(&range, dev, res);
> > +		if (err)
> > +			goto conversion_failed;
> > +
> > +		if (resource_type(res) == IORESOURCE_IO) {
> > +			if (!io_base) {
> > +				pr_err("I/O range found for %s. Please provide an io_base pointer to save CPU base address\n",
> > +					dev->full_name);
> > +				err = -EINVAL;
> > +				goto conversion_failed;
> > +			}
> > +			if (*io_base != (resource_size_t)OF_BAD_ADDR)
> > +				pr_warn("More than one I/O resource converted for %s. CPU base address for old range lost!\n",
> > +					dev->full_name);
> > +			*io_base = range.cpu_addr;
> > +		}
> > +
> > +		pci_add_resource_offset(resources, res,	res->start - range.pci_addr);
> > +	}
> > +
> > +	return 0;
> > +
> > +conversion_failed:
> > +	kfree(res);
> > +parse_failed:
> > +	pci_free_resource_list(resources);
> > +	return err;
> > +}
> > +EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources);
> > +#endif /* CONFIG_OF_ADDRESS */
> > +
> >  #ifdef CONFIG_PCI_MSI
> >  
> >  static LIST_HEAD(of_pci_msi_chip_list);
> > diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
> > index 71062e9..1fd207e 100644
> > --- a/include/linux/of_pci.h
> > +++ b/include/linux/of_pci.h
> > @@ -52,6 +52,12 @@ of_get_pci_domain_nr(struct device_node *node)
> >  }
> >  #endif
> >  
> > +#if defined(CONFIG_OF_ADDRESS)
> > +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);
> > +#endif
> > +
> >  #if defined(CONFIG_OF) && defined(CONFIG_PCI_MSI)
> >  int of_pci_msi_chip_add(struct msi_chip *chip);
> >  void of_pci_msi_chip_remove(struct msi_chip *chip);
> > -- 
> > 2.1.0
> > 
> > 
>

Will Deacon Sept. 24, 2014, 6:01 p.m. UTC | #3

On Wed, Sep 24, 2014 at 06:53:31PM +0100, Liviu Dudau wrote:
> On Wed, Sep 24, 2014 at 06:31:09PM +0100, Bjorn Helgaas wrote:
> > On Wed, Sep 24, 2014 at 05:43:04PM +0100, Liviu Dudau wrote:
> > > Provide a function to parse the PCI DT ranges that can be used to
> > > create a pci_host_bridge structure together with its associated
> > > bus.
> > > 
> > > Cc: Bjorn Helgaas <[e-mail]>
> > > Cc: Arnd Bergmann <[e-mail]>
> > > Cc: Grant Likely <[e-mail]>
> > > Cc: Rob Herring <[e-mail]>
> > > Cc: Catalin Marinas <[e-mail]>
> > > Signed-off-by: Liviu Dudau <[e-mail]>
> > > [make io_base parameter optional]
> > > Signed-off-by: Robert Richter <[e-mail]>
> > > ---
> > > Hi Bjorn,
> > > 
> > > I have fixed the compilation error that this patch was triggering. I
> > > have validated that the patch applies to your pci/host-generic branch
> > > as well as to my series.
> > 
> > I applied this to pci/host-generic along with the following patches and
> > pushed the branch, thanks!
> 
> Thanks again and sorry for lack of thorough testing. I still haven't managed
> to get a cross compiler for sparc and as I don't run Ubuntu or debian the
> make.cross script doesn't work for me.

  https://www.kernel.org/pub/tools/crosstool/

No libc, but good enough for building the kernel. I've asked for an aarch64
compiler there for a while, but it didn't materialise for some reason.

Will
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Liviu Dudau Sept. 25, 2014, 8:54 a.m. UTC | #4

On Wed, Sep 24, 2014 at 07:01:19PM +0100, Will Deacon wrote:
> On Wed, Sep 24, 2014 at 06:53:31PM +0100, Liviu Dudau wrote:
> > On Wed, Sep 24, 2014 at 06:31:09PM +0100, Bjorn Helgaas wrote:
> > > On Wed, Sep 24, 2014 at 05:43:04PM +0100, Liviu Dudau wrote:
> > > > Provide a function to parse the PCI DT ranges that can be used to
> > > > create a pci_host_bridge structure together with its associated
> > > > bus.
> > > > 
> > > > Cc: Bjorn Helgaas <[e-mail]>
> > > > Cc: Arnd Bergmann <[e-mail]>
> > > > Cc: Grant Likely <[e-mail]>
> > > > Cc: Rob Herring <[e-mail]>
> > > > Cc: Catalin Marinas <[e-mail]>
> > > > Signed-off-by: Liviu Dudau <[e-mail]>
> > > > [make io_base parameter optional]
> > > > Signed-off-by: Robert Richter <[e-mail]>
> > > > ---
> > > > Hi Bjorn,
> > > > 
> > > > I have fixed the compilation error that this patch was triggering. I
> > > > have validated that the patch applies to your pci/host-generic branch
> > > > as well as to my series.
> > > 
> > > I applied this to pci/host-generic along with the following patches and
> > > pushed the branch, thanks!
> > 
> > Thanks again and sorry for lack of thorough testing. I still haven't managed
> > to get a cross compiler for sparc and as I don't run Ubuntu or debian the
> > make.cross script doesn't work for me.
> 
>   https://www.kernel.org/pub/tools/crosstool/
> 
> No libc, but good enough for building the kernel. I've asked for an aarch64
> compiler there for a while, but it didn't materialise for some reason.

I'm familiar with crosstool and busybox uses a variant of crosstool-ng, but
it currently fails with "configure: error: cannot compute suffix of object files: cannot compile"
on the stage2 of the compilation.

Best regards,
Liviu

> 
> Will
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pci" in
> the body of a message to [e-mail]
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

Will Deacon Sept. 25, 2014, 9:04 a.m. UTC | #5

On Thu, Sep 25, 2014 at 09:54:32AM +0100, Liviu Dudau wrote:
> On Wed, Sep 24, 2014 at 07:01:19PM +0100, Will Deacon wrote:
> > On Wed, Sep 24, 2014 at 06:53:31PM +0100, Liviu Dudau wrote:
> > > Thanks again and sorry for lack of thorough testing. I still haven't managed
> > > to get a cross compiler for sparc and as I don't run Ubuntu or debian the
> > > make.cross script doesn't work for me.
> > 
> >   https://www.kernel.org/pub/tools/crosstool/
> > 
> > No libc, but good enough for building the kernel. I've asked for an aarch64
> > compiler there for a while, but it didn't materialise for some reason.
> 
> I'm familiar with crosstool and busybox uses a variant of crosstool-ng, but
> it currently fails with "configure: error: cannot compute suffix of object files: cannot compile"
> on the stage2 of the compilation.

Did you even follow the link? There are binary toolchains hosted there --
you don't have to build anything yourself if you don't want to.

Will
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Patch

diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 82d172f..3cad1af 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -1,7 +1,9 @@ 
 #include <linux/kernel.h>
 #include <linux/export.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
 #include <linux/of_pci.h>
+#include <linux/slab.h>
 
 static inline int __of_pci_pci_compare(struct device_node *node,
 				       unsigned int data)
@@ -114,6 +116,121 @@  int of_get_pci_domain_nr(struct device_node *node)
 }
 EXPORT_SYMBOL_GPL(of_get_pci_domain_nr);
 
+#if defined(CONFIG_OF_ADDRESS)
+/**
+ * of_pci_get_host_bridge_resources - Parse PCI host bridge resources from DT
+ * @dev: device node of the host bridge having the range property
+ * @busno: bus number associated with the bridge root bus
+ * @bus_max: maximum number of busses for this bridge
+ * @resources: list where the range of resources will be added after DT parsing
+ * @io_base: pointer to a variable that will contain on return the physical
+ * address for the start of the I/O range. Can be NULL if the caller doesn't
+ * expect IO ranges to be present in the device tree.
+ *
+ * It is the callers job to free the @resources list.
+ *
+ * This function will parse the "ranges" property of a PCI host bridge device
+ * node and setup the resource mapping based on its content. It is expected
+ * that the property conforms with the Power ePAPR document.
+ *
+ * It returns zero if the range parsing has been successful or a standard error
+ * value if it failed.
+ */
+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)
+		*io_base = (resource_size_t)OF_BAD_ADDR;
+
+	bus_range = kzalloc(sizeof(*bus_range), GFP_KERNEL);
+	if (!bus_range)
+		return -ENOMEM;
+
+	pr_info("PCI host bridge %s ranges:\n", dev->full_name);
+
+	err = of_pci_parse_bus_range(dev, bus_range);
+	if (err) {
+		bus_range->start = busno;
+		bus_range->end = bus_max;
+		bus_range->flags = IORESOURCE_BUS;
+		pr_info("  No bus range found for %s, using %pR\n",
+			dev->full_name, bus_range);
+	} else {
+		if (bus_range->end > bus_range->start + bus_max)
+			bus_range->end = bus_range->start + bus_max;
+	}
+	pci_add_resource(resources, bus_range);
+
+	/* Check for ranges property */
+	err = of_pci_range_parser_init(&parser, dev);
+	if (err)
+		goto parse_failed;
+
+	pr_debug("Parsing ranges property...\n");
+	for_each_of_pci_range(&parser, &range) {
+		/* Read next ranges element */
+		if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_IO)
+			snprintf(range_type, 4, " IO");
+		else if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM)
+			snprintf(range_type, 4, "MEM");
+		else
+			snprintf(range_type, 4, "err");
+		pr_info("  %s %#010llx..%#010llx -> %#010llx\n", range_type,
+			range.cpu_addr, range.cpu_addr + range.size - 1,
+			range.pci_addr);
+
+		/*
+		 * If we failed translation or got a zero-sized region
+		 * then skip this range
+		 */
+		if (range.cpu_addr == OF_BAD_ADDR || range.size == 0)
+			continue;
+
+		res = kzalloc(sizeof(struct resource), GFP_KERNEL);
+		if (!res) {
+			err = -ENOMEM;
+			goto parse_failed;
+		}
+
+		err = of_pci_range_to_resource(&range, dev, res);
+		if (err)
+			goto conversion_failed;
+
+		if (resource_type(res) == IORESOURCE_IO) {
+			if (!io_base) {
+				pr_err("I/O range found for %s. Please provide an io_base pointer to save CPU base address\n",
+					dev->full_name);
+				err = -EINVAL;
+				goto conversion_failed;
+			}
+			if (*io_base != (resource_size_t)OF_BAD_ADDR)
+				pr_warn("More than one I/O resource converted for %s. CPU base address for old range lost!\n",
+					dev->full_name);
+			*io_base = range.cpu_addr;
+		}
+
+		pci_add_resource_offset(resources, res,	res->start - range.pci_addr);
+	}
+
+	return 0;
+
+conversion_failed:
+	kfree(res);
+parse_failed:
+	pci_free_resource_list(resources);
+	return err;
+}
+EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources);
+#endif /* CONFIG_OF_ADDRESS */
+
 #ifdef CONFIG_PCI_MSI
 
 static LIST_HEAD(of_pci_msi_chip_list);
diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
index 71062e9..1fd207e 100644
--- a/include/linux/of_pci.h
+++ b/include/linux/of_pci.h
@@ -52,6 +52,12 @@  of_get_pci_domain_nr(struct device_node *node)
 }
 #endif
 
+#if defined(CONFIG_OF_ADDRESS)
+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);
+#endif
+
 #if defined(CONFIG_OF) && defined(CONFIG_PCI_MSI)
 int of_pci_msi_chip_add(struct msi_chip *chip);
 void of_pci_msi_chip_remove(struct msi_chip *chip);