[PATCH v7 2/6] pci: OF: Fix the conversion of IO ranges into IO resources.

Liviu Dudau
2014-03-14T17:19:22Z

On Fri, Mar 14, 2014 at 05:05:28PM +0000, Arnd Bergmann wrote:
> On Friday 14 March 2014, Liviu Dudau wrote:
> > +int of_pci_range_to_resource(struct of_pci_range *range,
> > + struct device_node *np, struct resource *res)
> > +{
> > + res->flags = range->flags;
> > + if (res->flags & IORESOURCE_IO) {
> > + unsigned long port = -1;
> > + int err = pci_register_io_range(range->cpu_addr, range->size);
> > + if (err)
> > + return err;
> > + port = pci_address_to_pio(range->cpu_addr);
> > + if (port == (unsigned long)-1) {
> > + res->start = (resource_size_t)OF_BAD_ADDR;
> > + res->end = (resource_size_t)OF_BAD_ADDR;
> > + return -EINVAL;
> > + }
>
> The error handling is inconsistent here: in one case you set the resource
> to OF_BAD_ADDR, in the other one you don't.
>
> Arnd
>

You are right, that was lazy of me. What about this version?

8<----------------------------------------------------

>From acfd63b5c48b4a9066ab0b373633c5bb4feaadf5 Mon Sep 17 00:00:00 2001
From: Liviu Dudau <Liviu.Dudau@arm.com>
Date: Fri, 28 Feb 2014 12:40:46 +0000
Subject: [PATCH v7 2/6] pci: OF: Fix the conversion of IO ranges into IO
resources.

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.

In the process move the function into drivers/of/address.c as it now
depends on pci_address_to_pio() code and make it return an error message.

Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Tested-by: Tanmay Inamdar <tinamdar@apm.com>
---
drivers/of/address.c | 45 ++++++++++++++++++++++++++++++++++++
include/linux/of_address.h | 13 ++---------
2 files changed, 47 insertions(+), 11 deletions(-)

diff --git a/drivers/of/address.c b/drivers/of/address.c
index be958ed..673c050 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -728,3 +728,48 @@ void __iomem *of_iomap(struct device_node *np, int index)
return ioremap(res.start, resource_size(&res));
}
EXPORT_SYMBOL(of_iomap);
+
+/**
+ * of_pci_range_to_resource - Create a resource from an of_pci_range
+ * @range: the PCI range that describes the resource
+ * @np: device node where the range belongs to
+ * @res: pointer to a valid resource that will be updated to
+ * reflect the values contained in the range.
+ *
+ * Returns EINVAL if the range cannot be converted to resource.
+ *
+ * Note that if the range is an IO range, the resource will be converted
+ * using pci_address_to_pio() which can fail if it is called too early or
+ * if the range cannot be matched to any host bridge IO space (our case here).
+ * To guard against that we try to register the IO range first.
+ * If that fails we know that pci_address_to_pio() will do too.
+ */
+int of_pci_range_to_resource(struct of_pci_range *range,
+ struct device_node *np, struct resource *res)
+{
+ res->flags = range->flags;
+ res->parent = res->child = res->sibling = NULL;
+ res->name = np->full_name;
+
+ if (res->flags & IORESOURCE_IO) {
+ unsigned long port = -1;
+ int err = pci_register_io_range(range->cpu_addr, range->size);
+ if (err)
+ goto invalid_range;
+ port = pci_address_to_pio(range->cpu_addr);
+ if (port == (unsigned long)-1) {
+ err = -EINVAL;
+ goto invalid_range;
+ }
+ res->start = port;
+ } else {
+ res->start = range->cpu_addr;
+ }
+ res->end = res->start + range->size - 1;
+ return 0;
+
+invalid_range:
+ res->start = (resource_size_t)OF_BAD_ADDR;
+ res->end = (resource_size_t)OF_BAD_ADDR;
+ return err;
+}
diff --git a/include/linux/of_address.h b/include/linux/of_address.h
index 40c418d..a4b400d 100644
--- a/include/linux/of_address.h
+++ b/include/linux/of_address.h
@@ -23,17 +23,8 @@ struct of_pci_range {
#define for_each_of_pci_range(parser, range) \
for (; of_pci_range_parser_one(parser, range);)

-static inline void of_pci_range_to_resource(struct of_pci_range *range,
- struct device_node *np,
- struct resource *res)
-{
- res->flags = range->flags;
- res->start = range->cpu_addr;
- res->end = range->cpu_addr + range->size - 1;
- res->parent = res->child = res->sibling = NULL;
- res->name = np->full_name;
-}
-
+extern int of_pci_range_to_resource(struct of_pci_range *range,
+ struct device_node *np, struct resource *res);
/* Translate a DMA address from device space to CPU space */
extern u64 of_translate_dma_address(struct device_node *dev,
const __be32 *in_addr);
--
1.9.0

>8--------------------------------------------------------

Best regards,
Liviu

--
====================
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| but they're not |
| giving me the |
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