2013-04-16 10:19:57

by Andrew Murray

[permalink] [raw]
Subject: [PATCH v7 0/3] of/pci: Provide common support for PCI DT parsing

This patchset factors out duplicated code associated with parsing PCI
DT "ranges" properties across the architectures and introduces a
"ranges" parser. This parser "of_pci_range_parser" can be used directly
by ARM host bridge drivers enabling them to obtain ranges from device
trees.

I've included the Reviewed-by and Tested-by's received from v5/v6 in this
patchset, earlier versions of this patchset (v3) have been tested-by:

Thierry Reding <[email protected]>
Jingoo Han <[email protected]>

I've tested that this patchset builds and runs on ARM and that it builds on
PowerPC and x86_64.

Compared to the v6 sent by Andrew Murray, the following changes have
been made in response to build errors/warnings:

* Inclusion of linux/of_address.h in of_pci.c as suggested by Michal
Simek to prevent compilation failures on Microblaze (and others) and his
ack.

* Use of externs, static inlines and a typo in linux/of_address.h in response
to linker errors (multiple defination) on x86_64 as spotted by a kbuild test
robot on (jcooper/linux.git mvebu/drivers)

* Add EXPORT_SYMBOL_GPL to of_pci_range_parser function to be consistent
with of_pci_process_ranges function

Compared to the v5 sent by Andrew Murray, the following changes have
been made:

* Use of CONFIG_64BIT instead of CONFIG_[a32bitarch] as suggested by
Rob Herring in drivers/of/of_pci.c

* Added forward declaration of struct pci_controller in linux/of_pci.h
to prevent compiler warning as suggested by Thomas Petazzoni

* Improved error checking (!range check), removal of unnecessary be32_to_cpup
call, improved formatting of struct of_pci_range_parser layout and
replacement of macro with a static inline. All suggested by Rob Herring.

Compared to the v4 (incorrectly labelled v3) sent by Andrew Murray,
the following changes have been made:

* Split the patch as suggested by Rob Herring

Compared to the v3 sent by Andrew Murray, the following changes have
been made:

* Unify and move duplicate pci_process_bridge_OF_ranges functions to
drivers/of/of_pci.c as suggested by Rob Herring

* Fix potential build errors with Microblaze/MIPS

Compared to "[PATCH v5 01/17] of/pci: Provide support for parsing PCI DT
ranges property", the following changes have been made:

* Correct use of IORESOURCE_* as suggested by Russell King

* Improved interface and naming as suggested by Thierry Reding

Compared to the v2 sent by Andrew Murray, Thomas Petazzoni did:

* Add a memset() on the struct of_pci_range_iter when starting the
for loop in for_each_pci_range(). Otherwise, with an uninitialized
of_pci_range_iter, of_pci_process_ranges() may crash.

* Add parenthesis around 'res', 'np' and 'iter' in the
for_each_of_pci_range macro definitions. Otherwise, passing
something like &foobar as 'res' didn't work.

* Rebased on top of 3.9-rc2, which required fixing a few conflicts in
the Microblaze code.

v2:
This follows on from suggestions made by Grant Likely
(marc.info/?l=linux-kernel&m=136079602806328)

Andrew Murray (3):
of/pci: Unify pci_process_bridge_OF_ranges from Microblaze and
PowerPC
of/pci: Provide support for parsing PCI DT ranges property
of/pci: mips: convert to common of_pci_range_parser

arch/microblaze/include/asm/pci-bridge.h | 5 +-
arch/microblaze/pci/pci-common.c | 192 ------------------------------
arch/mips/pci/pci.c | 50 +++------
arch/powerpc/include/asm/pci-bridge.h | 5 +-
arch/powerpc/kernel/pci-common.c | 192 ------------------------------
drivers/of/address.c | 67 +++++++++++
drivers/of/of_pci.c | 169 ++++++++++++++++++++++++++
include/linux/of_address.h | 46 +++++++
include/linux/of_pci.h | 4 +
9 files changed, 304 insertions(+), 426 deletions(-)


2013-04-16 10:19:59

by Andrew Murray

[permalink] [raw]
Subject: [PATCH v7 2/3] of/pci: Provide support for parsing PCI DT ranges property

This patch factors out common implementation patterns to reduce overall kernel
code and provide a means for host bridge drivers to directly obtain struct
resources from the DT's ranges property without relying on architecture specific
DT handling. This will make it easier to write archiecture independent host bridge
drivers and mitigate against further duplication of DT parsing code.

This patch can be used in the following way:

struct of_pci_range_parser parser;
struct of_pci_range range;

if (of_pci_range_parser(&parser, np))
; //no ranges property

for_each_of_pci_range(&parser, &range) {

/*
directly access properties of the address range, e.g.:
range.pci_space, range.pci_addr, range.cpu_addr,
range.size, range.flags

alternatively obtain a struct resource, e.g.:
struct resource res;
of_pci_range_to_resource(&range, np, &res);
*/
}

Additionally the implementation takes care of adjacent ranges and merges them
into a single range (as was the case with powerpc and microblaze).

Signed-off-by: Andrew Murray <[email protected]>
Signed-off-by: Liviu Dudau <[email protected]>
Signed-off-by: Thomas Petazzoni <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
Tested-by: Thomas Petazzoni <[email protected]>
Tested-by: Linus Walleij <[email protected]>
---
drivers/of/address.c | 67 ++++++++++++++++++++++++++
drivers/of/of_pci.c | 113 ++++++++++++++++----------------------------
include/linux/of_address.h | 46 ++++++++++++++++++
3 files changed, 154 insertions(+), 72 deletions(-)

diff --git a/drivers/of/address.c b/drivers/of/address.c
index 04da786..6eec70c 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -227,6 +227,73 @@ int of_pci_address_to_resource(struct device_node *dev, int bar,
return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
}
EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
+
+int of_pci_range_parser(struct of_pci_range_parser *parser,
+ struct device_node *node)
+{
+ const int na = 3, ns = 2;
+ int rlen;
+
+ parser->node = node;
+ parser->pna = of_n_addr_cells(node);
+ parser->np = parser->pna + na + ns;
+
+ parser->range = of_get_property(node, "ranges", &rlen);
+ if (parser->range == NULL)
+ return -ENOENT;
+
+ parser->end = parser->range + rlen / sizeof(__be32);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_pci_range_parser);
+
+struct of_pci_range *of_pci_process_ranges(struct of_pci_range_parser *parser,
+ struct of_pci_range *range)
+{
+ const int na = 3, ns = 2;
+
+ if (!range)
+ return NULL;
+
+ if (!parser->range || parser->range + parser->np > parser->end)
+ return NULL;
+
+ range->pci_space = parser->range[0];
+ range->flags = of_bus_pci_get_flags(parser->range);
+ range->pci_addr = of_read_number(parser->range + 1, ns);
+ range->cpu_addr = of_translate_address(parser->node,
+ parser->range + na);
+ range->size = of_read_number(parser->range + parser->pna + na, ns);
+
+ parser->range += parser->np;
+
+ /* Now consume following elements while they are contiguous */
+ while (parser->range + parser->np <= parser->end) {
+ u32 flags, pci_space;
+ u64 pci_addr, cpu_addr, size;
+
+ pci_space = be32_to_cpup(parser->range);
+ flags = of_bus_pci_get_flags(parser->range);
+ pci_addr = of_read_number(parser->range + 1, ns);
+ cpu_addr = of_translate_address(parser->node,
+ parser->range + na);
+ size = of_read_number(parser->range + parser->pna + na, ns);
+
+ if (flags != range->flags)
+ break;
+ if (pci_addr != range->pci_addr + range->size ||
+ cpu_addr != range->cpu_addr + range->size)
+ break;
+
+ range->size += size;
+ parser->range += parser->np;
+ }
+
+ return range;
+}
+EXPORT_SYMBOL_GPL(of_pci_process_ranges);
+
#endif /* CONFIG_PCI */

/*
diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 1626172..e5ab604 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -2,6 +2,7 @@
#include <linux/export.h>
#include <linux/of.h>
#include <linux/of_pci.h>
+#include <linux/of_address.h>
#include <asm/prom.h>

#if defined(CONFIG_PPC32) || defined(CONFIG_PPC64) || defined(CONFIG_MICROBLAZE)
@@ -82,67 +83,43 @@ EXPORT_SYMBOL_GPL(of_pci_find_child_device);
void pci_process_bridge_OF_ranges(struct pci_controller *hose,
struct device_node *dev, int primary)
{
- const u32 *ranges;
- int rlen;
- int pna = of_n_addr_cells(dev);
- int np = pna + 5;
int memno = 0, isa_hole = -1;
- u32 pci_space;
- unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
unsigned long long isa_mb = 0;
struct resource *res;
+ struct of_pci_range range;
+ struct of_pci_range_parser parser;
+ u32 res_type;

pr_info("PCI host bridge %s %s ranges:\n",
dev->full_name, primary ? "(primary)" : "");

- /* Get ranges property */
- ranges = of_get_property(dev, "ranges", &rlen);
- if (ranges == NULL)
+ /* Check for ranges property */
+ if (of_pci_range_parser(&parser, dev))
return;

- /* Parse it */
pr_debug("Parsing ranges property...\n");
- while ((rlen -= np * 4) >= 0) {
+ for_each_of_pci_range(&parser, &range) {
/* Read next ranges element */
- pci_space = ranges[0];
- pci_addr = of_read_number(ranges + 1, 2);
- cpu_addr = of_translate_address(dev, ranges + 3);
- size = of_read_number(ranges + pna + 3, 2);
-
- pr_debug("pci_space: 0x%08x pci_addr:0x%016llx ",
- pci_space, pci_addr);
- pr_debug("cpu_addr:0x%016llx size:0x%016llx\n",
- cpu_addr, size);
-
- ranges += np;
+ pr_debug("pci_space: 0x%08x pci_addr: 0x%016llx ",
+ range.pci_space, range.pci_addr);
+ pr_debug("cpu_addr: 0x%016llx size: 0x%016llx\n",
+ range.cpu_addr, range.size);

/* If we failed translation or got a zero-sized region
* (some FW try to feed us with non sensical zero sized regions
* such as power3 which look like some kind of attempt
* at exposing the VGA memory hole)
*/
- if (cpu_addr == OF_BAD_ADDR || size == 0)
+ if (range.cpu_addr == OF_BAD_ADDR || range.size == 0)
continue;

- /* Now consume following elements while they are contiguous */
- for (; rlen >= np * sizeof(u32);
- ranges += np, rlen -= np * 4) {
- if (ranges[0] != pci_space)
- break;
- pci_next = of_read_number(ranges + 1, 2);
- cpu_next = of_translate_address(dev, ranges + 3);
- if (pci_next != pci_addr + size ||
- cpu_next != cpu_addr + size)
- break;
- size += of_read_number(ranges + pna + 3, 2);
- }
-
/* Act based on address space type */
res = NULL;
- switch ((pci_space >> 24) & 0x3) {
- case 1: /* PCI IO space */
+ res_type = range.flags & IORESOURCE_TYPE_BITS;
+ if (res_type == IORESOURCE_IO) {
pr_info(" IO 0x%016llx..0x%016llx -> 0x%016llx\n",
- cpu_addr, cpu_addr + size - 1, pci_addr);
+ range.cpu_addr, range.cpu_addr + range.size - 1,
+ range.pci_addr);

/* We support only one IO range */
if (hose->pci_io_size) {
@@ -151,11 +128,12 @@ void pci_process_bridge_OF_ranges(struct pci_controller *hose,
}
#if (!IS_ENABLED(CONFIG_64BIT))
/* On 32 bits, limit I/O space to 16MB */
- if (size > 0x01000000)
- size = 0x01000000;
+ if (range.size > 0x01000000)
+ range.size = 0x01000000;

/* 32 bits needs to map IOs here */
- hose->io_base_virt = ioremap(cpu_addr, size);
+ hose->io_base_virt = ioremap(range.cpu_addr,
+ range.size);

/* Expect trouble if pci_addr is not 0 */
if (primary)
@@ -165,19 +143,18 @@ void pci_process_bridge_OF_ranges(struct pci_controller *hose,
/* pci_io_size and io_base_phys always represent IO
* space starting at 0 so we factor in pci_addr
*/
- hose->pci_io_size = pci_addr + size;
- hose->io_base_phys = cpu_addr - pci_addr;
+ hose->pci_io_size = range.pci_addr + range.size;
+ hose->io_base_phys = range.cpu_addr - range.pci_addr;

/* Build resource */
res = &hose->io_resource;
- res->flags = IORESOURCE_IO;
- res->start = pci_addr;
- break;
- case 2: /* PCI Memory space */
- case 3: /* PCI 64 bits Memory space */
+ range.cpu_addr = range.pci_addr;
+ } else if (res_type == IORESOURCE_MEM) {
pr_info(" MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
- cpu_addr, cpu_addr + size - 1, pci_addr,
- (pci_space & 0x40000000) ? "Prefetch" : "");
+ range.cpu_addr, range.cpu_addr + range.size - 1,
+ range.pci_addr,
+ (range.pci_space & 0x40000000) ?
+ "Prefetch" : "");

/* We support only 3 memory ranges */
if (memno >= 3) {
@@ -185,13 +162,13 @@ void pci_process_bridge_OF_ranges(struct pci_controller *hose,
continue;
}
/* Handles ISA memory hole space here */
- if (pci_addr == 0) {
- isa_mb = cpu_addr;
+ if (range.pci_addr == 0) {
+ isa_mb = range.cpu_addr;
isa_hole = memno;
if (primary || isa_mem_base == 0)
- isa_mem_base = cpu_addr;
- hose->isa_mem_phys = cpu_addr;
- hose->isa_mem_size = size;
+ isa_mem_base = range.cpu_addr;
+ hose->isa_mem_phys = range.cpu_addr;
+ hose->isa_mem_size = range.size;
}

/* We get the PCI/Mem offset from the first range or
@@ -199,30 +176,22 @@ void pci_process_bridge_OF_ranges(struct pci_controller *hose,
* hole. If they don't match, bugger.
*/
if (memno == 0 ||
- (isa_hole >= 0 && pci_addr != 0 &&
+ (isa_hole >= 0 && range.pci_addr != 0 &&
hose->pci_mem_offset == isa_mb))
- hose->pci_mem_offset = cpu_addr - pci_addr;
- else if (pci_addr != 0 &&
- hose->pci_mem_offset != cpu_addr - pci_addr) {
+ hose->pci_mem_offset = range.cpu_addr -
+ range.pci_addr;
+ else if (range.pci_addr != 0 &&
+ hose->pci_mem_offset != range.cpu_addr -
+ range.pci_addr) {
pr_info(" \\--> Skipped (offset mismatch) !\n");
continue;
}

/* Build resource */
res = &hose->mem_resources[memno++];
- res->flags = IORESOURCE_MEM;
- if (pci_space & 0x40000000)
- res->flags |= IORESOURCE_PREFETCH;
- res->start = cpu_addr;
- break;
- }
- if (res != NULL) {
- res->name = dev->full_name;
- res->end = res->start + size - 1;
- res->parent = NULL;
- res->sibling = NULL;
- res->child = NULL;
}
+ if (res != NULL)
+ of_pci_range_to_resource(&range, dev, res);
}

/* If there's an ISA hole and the pci_mem_offset is -not- matching
diff --git a/include/linux/of_address.h b/include/linux/of_address.h
index 0506eb5..1cfb779 100644
--- a/include/linux/of_address.h
+++ b/include/linux/of_address.h
@@ -4,6 +4,36 @@
#include <linux/errno.h>
#include <linux/of.h>

+struct of_pci_range_parser {
+ struct device_node *node;
+ const __be32 *range;
+ const __be32 *end;
+ int np;
+ int pna;
+};
+
+struct of_pci_range {
+ u32 pci_space;
+ u64 pci_addr;
+ u64 cpu_addr;
+ u64 size;
+ u32 flags;
+};
+
+#define for_each_of_pci_range(parser, range) \
+ for (; of_pci_process_ranges(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;
+}
+
#ifdef CONFIG_OF_ADDRESS
extern u64 of_translate_address(struct device_node *np, const __be32 *addr);
extern bool of_can_translate_address(struct device_node *dev);
@@ -27,6 +57,10 @@ static inline unsigned long pci_address_to_pio(phys_addr_t addr) { return -1; }
#define pci_address_to_pio pci_address_to_pio
#endif

+extern int of_pci_range_parser(struct of_pci_range_parser *parser,
+ struct device_node *node);
+extern struct of_pci_range *of_pci_process_ranges(struct of_pci_range_parser *parser,
+ struct of_pci_range *range);
#else /* CONFIG_OF_ADDRESS */
#ifndef of_address_to_resource
static inline int of_address_to_resource(struct device_node *dev, int index,
@@ -53,6 +87,18 @@ static inline const __be32 *of_get_address(struct device_node *dev, int index,
{
return NULL;
}
+
+static inline int of_pci_range_parser(struct of_pci_range_parser *parser,
+ struct device_node *node)
+{
+ return -1;
+}
+
+static inline struct of_pci_range *of_pci_process_ranges(struct of_pci_range_parser *parser,
+ struct of_pci_range *range)
+{
+ return NULL;
+}
#endif /* CONFIG_OF_ADDRESS */


--
1.7.0.4

2013-04-16 10:19:58

by Andrew Murray

[permalink] [raw]
Subject: [PATCH v7 3/3] of/pci: mips: convert to common of_pci_range_parser

This patch converts the pci_load_of_ranges function to use the new common
of_pci_range_parser.

Signed-off-by: Andrew Murray <[email protected]>
Signed-off-by: Liviu Dudau <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
---
arch/mips/pci/pci.c | 50 ++++++++++++++++----------------------------------
1 files changed, 16 insertions(+), 34 deletions(-)

diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c
index 0872f12..bee49a4 100644
--- a/arch/mips/pci/pci.c
+++ b/arch/mips/pci/pci.c
@@ -122,51 +122,33 @@ static void pcibios_scanbus(struct pci_controller *hose)
#ifdef CONFIG_OF
void pci_load_of_ranges(struct pci_controller *hose, struct device_node *node)
{
- const __be32 *ranges;
- int rlen;
- int pna = of_n_addr_cells(node);
- int np = pna + 5;
+ struct of_pci_range_range range;
+ struct of_pci_range_parser parser;
+ u32 res_type;

pr_info("PCI host bridge %s ranges:\n", node->full_name);
- ranges = of_get_property(node, "ranges", &rlen);
- if (ranges == NULL)
- return;
hose->of_node = node;

- while ((rlen -= np * 4) >= 0) {
- u32 pci_space;
+ if (of_pci_range_parser(&parser, node))
+ return;
+
+ for_each_of_pci_range(&parser, &range) {
struct resource *res = NULL;
- u64 addr, size;
-
- pci_space = be32_to_cpup(&ranges[0]);
- addr = of_translate_address(node, ranges + 3);
- size = of_read_number(ranges + pna + 3, 2);
- ranges += np;
- switch ((pci_space >> 24) & 0x3) {
- case 1: /* PCI IO space */
+
+ res_type = range.flags & IORESOURCE_TYPE_BITS;
+ if (res_type == IORESOURCE_IO) {
pr_info(" IO 0x%016llx..0x%016llx\n",
- addr, addr + size - 1);
+ range.addr, range.addr + range.size - 1);
hose->io_map_base =
- (unsigned long)ioremap(addr, size);
+ (unsigned long)ioremap(range.addr, range.size);
res = hose->io_resource;
- res->flags = IORESOURCE_IO;
- break;
- case 2: /* PCI Memory space */
- case 3: /* PCI 64 bits Memory space */
+ } else if (res_type == IORESOURCE_MEM) {
pr_info(" MEM 0x%016llx..0x%016llx\n",
- addr, addr + size - 1);
+ range.addr, range.addr + range.size - 1);
res = hose->mem_resource;
- res->flags = IORESOURCE_MEM;
- break;
- }
- if (res != NULL) {
- res->start = addr;
- res->name = node->full_name;
- res->end = res->start + size - 1;
- res->parent = NULL;
- res->sibling = NULL;
- res->child = NULL;
}
+ if (res != NULL)
+ of_pci_range_to_resource(&range, node, res);
}
}
#endif
--
1.7.0.4

2013-04-16 10:21:14

by Andrew Murray

[permalink] [raw]
Subject: [PATCH v7 1/3] of/pci: Unify pci_process_bridge_OF_ranges from Microblaze and PowerPC

The pci_process_bridge_OF_ranges function, used to parse the "ranges"
property of a PCI host device, is found in both Microblaze and PowerPC
architectures. These implementations are nearly identical. This patch
moves this common code to a common place.

Signed-off-by: Andrew Murray <[email protected]>
Signed-off-by: Liviu Dudau <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
Tested-by: Thomas Petazzoni <[email protected]>
Tested-by: Linus Walleij <[email protected]>
Acked-by: Michal Simek <[email protected]>
---
arch/microblaze/include/asm/pci-bridge.h | 5 +-
arch/microblaze/pci/pci-common.c | 192 ----------------------------
arch/powerpc/include/asm/pci-bridge.h | 5 +-
arch/powerpc/kernel/pci-common.c | 192 ----------------------------
drivers/of/of_pci.c | 200 ++++++++++++++++++++++++++++++
include/linux/of_pci.h | 4 +
6 files changed, 206 insertions(+), 392 deletions(-)

diff --git a/arch/microblaze/include/asm/pci-bridge.h b/arch/microblaze/include/asm/pci-bridge.h
index cb5d397..5783cd6 100644
--- a/arch/microblaze/include/asm/pci-bridge.h
+++ b/arch/microblaze/include/asm/pci-bridge.h
@@ -10,6 +10,7 @@
#include <linux/pci.h>
#include <linux/list.h>
#include <linux/ioport.h>
+#include <linux/of_pci.h>

struct device_node;

@@ -132,10 +133,6 @@ extern void setup_indirect_pci(struct pci_controller *hose,
extern struct pci_controller *pci_find_hose_for_OF_device(
struct device_node *node);

-/* Fill up host controller resources from the OF node */
-extern void pci_process_bridge_OF_ranges(struct pci_controller *hose,
- struct device_node *dev, int primary);
-
/* Allocate & free a PCI host bridge structure */
extern struct pci_controller *pcibios_alloc_controller(struct device_node *dev);
extern void pcibios_free_controller(struct pci_controller *phb);
diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
index 9ea521e..2735ad9 100644
--- a/arch/microblaze/pci/pci-common.c
+++ b/arch/microblaze/pci/pci-common.c
@@ -622,198 +622,6 @@ void pci_resource_to_user(const struct pci_dev *dev, int bar,
*end = rsrc->end - offset;
}

-/**
- * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
- * @hose: newly allocated pci_controller to be setup
- * @dev: device node of the host bridge
- * @primary: set if primary bus (32 bits only, soon to be deprecated)
- *
- * This function will parse the "ranges" property of a PCI host bridge device
- * node and setup the resource mapping of a pci controller based on its
- * content.
- *
- * Life would be boring if it wasn't for a few issues that we have to deal
- * with here:
- *
- * - We can only cope with one IO space range and up to 3 Memory space
- * ranges. However, some machines (thanks Apple !) tend to split their
- * space into lots of small contiguous ranges. So we have to coalesce.
- *
- * - We can only cope with all memory ranges having the same offset
- * between CPU addresses and PCI addresses. Unfortunately, some bridges
- * are setup for a large 1:1 mapping along with a small "window" which
- * maps PCI address 0 to some arbitrary high address of the CPU space in
- * order to give access to the ISA memory hole.
- * The way out of here that I've chosen for now is to always set the
- * offset based on the first resource found, then override it if we
- * have a different offset and the previous was set by an ISA hole.
- *
- * - Some busses have IO space not starting at 0, which causes trouble with
- * the way we do our IO resource renumbering. The code somewhat deals with
- * it for 64 bits but I would expect problems on 32 bits.
- *
- * - Some 32 bits platforms such as 4xx can have physical space larger than
- * 32 bits so we need to use 64 bits values for the parsing
- */
-void pci_process_bridge_OF_ranges(struct pci_controller *hose,
- struct device_node *dev, int primary)
-{
- const u32 *ranges;
- int rlen;
- int pna = of_n_addr_cells(dev);
- int np = pna + 5;
- int memno = 0, isa_hole = -1;
- u32 pci_space;
- unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
- unsigned long long isa_mb = 0;
- struct resource *res;
-
- pr_info("PCI host bridge %s %s ranges:\n",
- dev->full_name, primary ? "(primary)" : "");
-
- /* Get ranges property */
- ranges = of_get_property(dev, "ranges", &rlen);
- if (ranges == NULL)
- return;
-
- /* Parse it */
- pr_debug("Parsing ranges property...\n");
- while ((rlen -= np * 4) >= 0) {
- /* Read next ranges element */
- pci_space = ranges[0];
- pci_addr = of_read_number(ranges + 1, 2);
- cpu_addr = of_translate_address(dev, ranges + 3);
- size = of_read_number(ranges + pna + 3, 2);
-
- pr_debug("pci_space: 0x%08x pci_addr:0x%016llx ",
- pci_space, pci_addr);
- pr_debug("cpu_addr:0x%016llx size:0x%016llx\n",
- cpu_addr, size);
-
- ranges += np;
-
- /* If we failed translation or got a zero-sized region
- * (some FW try to feed us with non sensical zero sized regions
- * such as power3 which look like some kind of attempt
- * at exposing the VGA memory hole)
- */
- if (cpu_addr == OF_BAD_ADDR || size == 0)
- continue;
-
- /* Now consume following elements while they are contiguous */
- for (; rlen >= np * sizeof(u32);
- ranges += np, rlen -= np * 4) {
- if (ranges[0] != pci_space)
- break;
- pci_next = of_read_number(ranges + 1, 2);
- cpu_next = of_translate_address(dev, ranges + 3);
- if (pci_next != pci_addr + size ||
- cpu_next != cpu_addr + size)
- break;
- size += of_read_number(ranges + pna + 3, 2);
- }
-
- /* Act based on address space type */
- res = NULL;
- switch ((pci_space >> 24) & 0x3) {
- case 1: /* PCI IO space */
- pr_info(" IO 0x%016llx..0x%016llx -> 0x%016llx\n",
- cpu_addr, cpu_addr + size - 1, pci_addr);
-
- /* We support only one IO range */
- if (hose->pci_io_size) {
- pr_info(" \\--> Skipped (too many) !\n");
- continue;
- }
- /* On 32 bits, limit I/O space to 16MB */
- if (size > 0x01000000)
- size = 0x01000000;
-
- /* 32 bits needs to map IOs here */
- hose->io_base_virt = ioremap(cpu_addr, size);
-
- /* Expect trouble if pci_addr is not 0 */
- if (primary)
- isa_io_base =
- (unsigned long)hose->io_base_virt;
- /* pci_io_size and io_base_phys always represent IO
- * space starting at 0 so we factor in pci_addr
- */
- hose->pci_io_size = pci_addr + size;
- hose->io_base_phys = cpu_addr - pci_addr;
-
- /* Build resource */
- res = &hose->io_resource;
- res->flags = IORESOURCE_IO;
- res->start = pci_addr;
- break;
- case 2: /* PCI Memory space */
- case 3: /* PCI 64 bits Memory space */
- pr_info(" MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
- cpu_addr, cpu_addr + size - 1, pci_addr,
- (pci_space & 0x40000000) ? "Prefetch" : "");
-
- /* We support only 3 memory ranges */
- if (memno >= 3) {
- pr_info(" \\--> Skipped (too many) !\n");
- continue;
- }
- /* Handles ISA memory hole space here */
- if (pci_addr == 0) {
- isa_mb = cpu_addr;
- isa_hole = memno;
- if (primary || isa_mem_base == 0)
- isa_mem_base = cpu_addr;
- hose->isa_mem_phys = cpu_addr;
- hose->isa_mem_size = size;
- }
-
- /* We get the PCI/Mem offset from the first range or
- * the, current one if the offset came from an ISA
- * hole. If they don't match, bugger.
- */
- if (memno == 0 ||
- (isa_hole >= 0 && pci_addr != 0 &&
- hose->pci_mem_offset == isa_mb))
- hose->pci_mem_offset = cpu_addr - pci_addr;
- else if (pci_addr != 0 &&
- hose->pci_mem_offset != cpu_addr - pci_addr) {
- pr_info(" \\--> Skipped (offset mismatch) !\n");
- continue;
- }
-
- /* Build resource */
- res = &hose->mem_resources[memno++];
- res->flags = IORESOURCE_MEM;
- if (pci_space & 0x40000000)
- res->flags |= IORESOURCE_PREFETCH;
- res->start = cpu_addr;
- break;
- }
- if (res != NULL) {
- res->name = dev->full_name;
- res->end = res->start + size - 1;
- res->parent = NULL;
- res->sibling = NULL;
- res->child = NULL;
- }
- }
-
- /* If there's an ISA hole and the pci_mem_offset is -not- matching
- * the ISA hole offset, then we need to remove the ISA hole from
- * the resource list for that brige
- */
- if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
- unsigned int next = isa_hole + 1;
- pr_info(" Removing ISA hole at 0x%016llx\n", isa_mb);
- if (next < memno)
- memmove(&hose->mem_resources[isa_hole],
- &hose->mem_resources[next],
- sizeof(struct resource) * (memno - next));
- hose->mem_resources[--memno].flags = 0;
- }
-}
-
/* Decide whether to display the domain number in /proc */
int pci_proc_domain(struct pci_bus *bus)
{
diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
index 025a130..205bfba 100644
--- a/arch/powerpc/include/asm/pci-bridge.h
+++ b/arch/powerpc/include/asm/pci-bridge.h
@@ -10,6 +10,7 @@
#include <linux/pci.h>
#include <linux/list.h>
#include <linux/ioport.h>
+#include <linux/of_pci.h>
#include <asm-generic/pci-bridge.h>

struct device_node;
@@ -231,10 +232,6 @@ extern int pcibios_map_io_space(struct pci_bus *bus);
extern struct pci_controller *pci_find_hose_for_OF_device(
struct device_node* node);

-/* Fill up host controller resources from the OF node */
-extern void pci_process_bridge_OF_ranges(struct pci_controller *hose,
- struct device_node *dev, int primary);
-
/* Allocate & free a PCI host bridge structure */
extern struct pci_controller *pcibios_alloc_controller(struct device_node *dev);
extern void pcibios_free_controller(struct pci_controller *phb);
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index fa12ae4..6edf396 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -640,198 +640,6 @@ void pci_resource_to_user(const struct pci_dev *dev, int bar,
*end = rsrc->end - offset;
}

-/**
- * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
- * @hose: newly allocated pci_controller to be setup
- * @dev: device node of the host bridge
- * @primary: set if primary bus (32 bits only, soon to be deprecated)
- *
- * This function will parse the "ranges" property of a PCI host bridge device
- * node and setup the resource mapping of a pci controller based on its
- * content.
- *
- * Life would be boring if it wasn't for a few issues that we have to deal
- * with here:
- *
- * - We can only cope with one IO space range and up to 3 Memory space
- * ranges. However, some machines (thanks Apple !) tend to split their
- * space into lots of small contiguous ranges. So we have to coalesce.
- *
- * - We can only cope with all memory ranges having the same offset
- * between CPU addresses and PCI addresses. Unfortunately, some bridges
- * are setup for a large 1:1 mapping along with a small "window" which
- * maps PCI address 0 to some arbitrary high address of the CPU space in
- * order to give access to the ISA memory hole.
- * The way out of here that I've chosen for now is to always set the
- * offset based on the first resource found, then override it if we
- * have a different offset and the previous was set by an ISA hole.
- *
- * - Some busses have IO space not starting at 0, which causes trouble with
- * the way we do our IO resource renumbering. The code somewhat deals with
- * it for 64 bits but I would expect problems on 32 bits.
- *
- * - Some 32 bits platforms such as 4xx can have physical space larger than
- * 32 bits so we need to use 64 bits values for the parsing
- */
-void pci_process_bridge_OF_ranges(struct pci_controller *hose,
- struct device_node *dev, int primary)
-{
- const u32 *ranges;
- int rlen;
- int pna = of_n_addr_cells(dev);
- int np = pna + 5;
- int memno = 0, isa_hole = -1;
- u32 pci_space;
- unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
- unsigned long long isa_mb = 0;
- struct resource *res;
-
- printk(KERN_INFO "PCI host bridge %s %s ranges:\n",
- dev->full_name, primary ? "(primary)" : "");
-
- /* Get ranges property */
- ranges = of_get_property(dev, "ranges", &rlen);
- if (ranges == NULL)
- return;
-
- /* Parse it */
- while ((rlen -= np * 4) >= 0) {
- /* Read next ranges element */
- pci_space = ranges[0];
- pci_addr = of_read_number(ranges + 1, 2);
- cpu_addr = of_translate_address(dev, ranges + 3);
- size = of_read_number(ranges + pna + 3, 2);
- ranges += np;
-
- /* If we failed translation or got a zero-sized region
- * (some FW try to feed us with non sensical zero sized regions
- * such as power3 which look like some kind of attempt at exposing
- * the VGA memory hole)
- */
- if (cpu_addr == OF_BAD_ADDR || size == 0)
- continue;
-
- /* Now consume following elements while they are contiguous */
- for (; rlen >= np * sizeof(u32);
- ranges += np, rlen -= np * 4) {
- if (ranges[0] != pci_space)
- break;
- pci_next = of_read_number(ranges + 1, 2);
- cpu_next = of_translate_address(dev, ranges + 3);
- if (pci_next != pci_addr + size ||
- cpu_next != cpu_addr + size)
- break;
- size += of_read_number(ranges + pna + 3, 2);
- }
-
- /* Act based on address space type */
- res = NULL;
- switch ((pci_space >> 24) & 0x3) {
- case 1: /* PCI IO space */
- printk(KERN_INFO
- " IO 0x%016llx..0x%016llx -> 0x%016llx\n",
- cpu_addr, cpu_addr + size - 1, pci_addr);
-
- /* We support only one IO range */
- if (hose->pci_io_size) {
- printk(KERN_INFO
- " \\--> Skipped (too many) !\n");
- continue;
- }
-#ifdef CONFIG_PPC32
- /* On 32 bits, limit I/O space to 16MB */
- if (size > 0x01000000)
- size = 0x01000000;
-
- /* 32 bits needs to map IOs here */
- hose->io_base_virt = ioremap(cpu_addr, size);
-
- /* Expect trouble if pci_addr is not 0 */
- if (primary)
- isa_io_base =
- (unsigned long)hose->io_base_virt;
-#endif /* CONFIG_PPC32 */
- /* pci_io_size and io_base_phys always represent IO
- * space starting at 0 so we factor in pci_addr
- */
- hose->pci_io_size = pci_addr + size;
- hose->io_base_phys = cpu_addr - pci_addr;
-
- /* Build resource */
- res = &hose->io_resource;
- res->flags = IORESOURCE_IO;
- res->start = pci_addr;
- break;
- case 2: /* PCI Memory space */
- case 3: /* PCI 64 bits Memory space */
- printk(KERN_INFO
- " MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
- cpu_addr, cpu_addr + size - 1, pci_addr,
- (pci_space & 0x40000000) ? "Prefetch" : "");
-
- /* We support only 3 memory ranges */
- if (memno >= 3) {
- printk(KERN_INFO
- " \\--> Skipped (too many) !\n");
- continue;
- }
- /* Handles ISA memory hole space here */
- if (pci_addr == 0) {
- isa_mb = cpu_addr;
- isa_hole = memno;
- if (primary || isa_mem_base == 0)
- isa_mem_base = cpu_addr;
- hose->isa_mem_phys = cpu_addr;
- hose->isa_mem_size = size;
- }
-
- /* We get the PCI/Mem offset from the first range or
- * the, current one if the offset came from an ISA
- * hole. If they don't match, bugger.
- */
- if (memno == 0 ||
- (isa_hole >= 0 && pci_addr != 0 &&
- hose->pci_mem_offset == isa_mb))
- hose->pci_mem_offset = cpu_addr - pci_addr;
- else if (pci_addr != 0 &&
- hose->pci_mem_offset != cpu_addr - pci_addr) {
- printk(KERN_INFO
- " \\--> Skipped (offset mismatch) !\n");
- continue;
- }
-
- /* Build resource */
- res = &hose->mem_resources[memno++];
- res->flags = IORESOURCE_MEM;
- if (pci_space & 0x40000000)
- res->flags |= IORESOURCE_PREFETCH;
- res->start = cpu_addr;
- break;
- }
- if (res != NULL) {
- res->name = dev->full_name;
- res->end = res->start + size - 1;
- res->parent = NULL;
- res->sibling = NULL;
- res->child = NULL;
- }
- }
-
- /* If there's an ISA hole and the pci_mem_offset is -not- matching
- * the ISA hole offset, then we need to remove the ISA hole from
- * the resource list for that brige
- */
- if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
- unsigned int next = isa_hole + 1;
- printk(KERN_INFO " Removing ISA hole at 0x%016llx\n", isa_mb);
- if (next < memno)
- memmove(&hose->mem_resources[isa_hole],
- &hose->mem_resources[next],
- sizeof(struct resource) * (memno - next));
- hose->mem_resources[--memno].flags = 0;
- }
-}
-
/* Decide whether to display the domain number in /proc */
int pci_proc_domain(struct pci_bus *bus)
{
diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 13e37e2..1626172 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -4,6 +4,10 @@
#include <linux/of_pci.h>
#include <asm/prom.h>

+#if defined(CONFIG_PPC32) || defined(CONFIG_PPC64) || defined(CONFIG_MICROBLAZE)
+#include <asm/pci-bridge.h>
+#endif
+
static inline int __of_pci_pci_compare(struct device_node *node,
unsigned int devfn)
{
@@ -40,3 +44,199 @@ struct device_node *of_pci_find_child_device(struct device_node *parent,
return NULL;
}
EXPORT_SYMBOL_GPL(of_pci_find_child_device);
+
+/**
+ * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
+ * @hose: newly allocated pci_controller to be setup
+ * @dev: device node of the host bridge
+ * @primary: set if primary bus (32 bits only, soon to be deprecated)
+ *
+ * This function will parse the "ranges" property of a PCI host bridge device
+ * node and setup the resource mapping of a pci controller based on its
+ * content.
+ *
+ * Life would be boring if it wasn't for a few issues that we have to deal
+ * with here:
+ *
+ * - We can only cope with one IO space range and up to 3 Memory space
+ * ranges. However, some machines (thanks Apple !) tend to split their
+ * space into lots of small contiguous ranges. So we have to coalesce.
+ *
+ * - We can only cope with all memory ranges having the same offset
+ * between CPU addresses and PCI addresses. Unfortunately, some bridges
+ * are setup for a large 1:1 mapping along with a small "window" which
+ * maps PCI address 0 to some arbitrary high address of the CPU space in
+ * order to give access to the ISA memory hole.
+ * The way out of here that I've chosen for now is to always set the
+ * offset based on the first resource found, then override it if we
+ * have a different offset and the previous was set by an ISA hole.
+ *
+ * - Some busses have IO space not starting at 0, which causes trouble with
+ * the way we do our IO resource renumbering. The code somewhat deals with
+ * it for 64 bits but I would expect problems on 32 bits.
+ *
+ * - Some 32 bits platforms such as 4xx can have physical space larger than
+ * 32 bits so we need to use 64 bits values for the parsing
+ */
+#if defined(CONFIG_PPC32) || defined(CONFIG_PPC64) || defined(CONFIG_MICROBLAZE)
+void pci_process_bridge_OF_ranges(struct pci_controller *hose,
+ struct device_node *dev, int primary)
+{
+ const u32 *ranges;
+ int rlen;
+ int pna = of_n_addr_cells(dev);
+ int np = pna + 5;
+ int memno = 0, isa_hole = -1;
+ u32 pci_space;
+ unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
+ unsigned long long isa_mb = 0;
+ struct resource *res;
+
+ pr_info("PCI host bridge %s %s ranges:\n",
+ dev->full_name, primary ? "(primary)" : "");
+
+ /* Get ranges property */
+ ranges = of_get_property(dev, "ranges", &rlen);
+ if (ranges == NULL)
+ return;
+
+ /* Parse it */
+ pr_debug("Parsing ranges property...\n");
+ while ((rlen -= np * 4) >= 0) {
+ /* Read next ranges element */
+ pci_space = ranges[0];
+ pci_addr = of_read_number(ranges + 1, 2);
+ cpu_addr = of_translate_address(dev, ranges + 3);
+ size = of_read_number(ranges + pna + 3, 2);
+
+ pr_debug("pci_space: 0x%08x pci_addr:0x%016llx ",
+ pci_space, pci_addr);
+ pr_debug("cpu_addr:0x%016llx size:0x%016llx\n",
+ cpu_addr, size);
+
+ ranges += np;
+
+ /* If we failed translation or got a zero-sized region
+ * (some FW try to feed us with non sensical zero sized regions
+ * such as power3 which look like some kind of attempt
+ * at exposing the VGA memory hole)
+ */
+ if (cpu_addr == OF_BAD_ADDR || size == 0)
+ continue;
+
+ /* Now consume following elements while they are contiguous */
+ for (; rlen >= np * sizeof(u32);
+ ranges += np, rlen -= np * 4) {
+ if (ranges[0] != pci_space)
+ break;
+ pci_next = of_read_number(ranges + 1, 2);
+ cpu_next = of_translate_address(dev, ranges + 3);
+ if (pci_next != pci_addr + size ||
+ cpu_next != cpu_addr + size)
+ break;
+ size += of_read_number(ranges + pna + 3, 2);
+ }
+
+ /* Act based on address space type */
+ res = NULL;
+ switch ((pci_space >> 24) & 0x3) {
+ case 1: /* PCI IO space */
+ pr_info(" IO 0x%016llx..0x%016llx -> 0x%016llx\n",
+ cpu_addr, cpu_addr + size - 1, pci_addr);
+
+ /* We support only one IO range */
+ if (hose->pci_io_size) {
+ pr_info(" \\--> Skipped (too many) !\n");
+ continue;
+ }
+#if (!IS_ENABLED(CONFIG_64BIT))
+ /* On 32 bits, limit I/O space to 16MB */
+ if (size > 0x01000000)
+ size = 0x01000000;
+
+ /* 32 bits needs to map IOs here */
+ hose->io_base_virt = ioremap(cpu_addr, size);
+
+ /* Expect trouble if pci_addr is not 0 */
+ if (primary)
+ isa_io_base =
+ (unsigned long)hose->io_base_virt;
+#endif /* !CONFIG_64BIT */
+ /* pci_io_size and io_base_phys always represent IO
+ * space starting at 0 so we factor in pci_addr
+ */
+ hose->pci_io_size = pci_addr + size;
+ hose->io_base_phys = cpu_addr - pci_addr;
+
+ /* Build resource */
+ res = &hose->io_resource;
+ res->flags = IORESOURCE_IO;
+ res->start = pci_addr;
+ break;
+ case 2: /* PCI Memory space */
+ case 3: /* PCI 64 bits Memory space */
+ pr_info(" MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
+ cpu_addr, cpu_addr + size - 1, pci_addr,
+ (pci_space & 0x40000000) ? "Prefetch" : "");
+
+ /* We support only 3 memory ranges */
+ if (memno >= 3) {
+ pr_info(" \\--> Skipped (too many) !\n");
+ continue;
+ }
+ /* Handles ISA memory hole space here */
+ if (pci_addr == 0) {
+ isa_mb = cpu_addr;
+ isa_hole = memno;
+ if (primary || isa_mem_base == 0)
+ isa_mem_base = cpu_addr;
+ hose->isa_mem_phys = cpu_addr;
+ hose->isa_mem_size = size;
+ }
+
+ /* We get the PCI/Mem offset from the first range or
+ * the, current one if the offset came from an ISA
+ * hole. If they don't match, bugger.
+ */
+ if (memno == 0 ||
+ (isa_hole >= 0 && pci_addr != 0 &&
+ hose->pci_mem_offset == isa_mb))
+ hose->pci_mem_offset = cpu_addr - pci_addr;
+ else if (pci_addr != 0 &&
+ hose->pci_mem_offset != cpu_addr - pci_addr) {
+ pr_info(" \\--> Skipped (offset mismatch) !\n");
+ continue;
+ }
+
+ /* Build resource */
+ res = &hose->mem_resources[memno++];
+ res->flags = IORESOURCE_MEM;
+ if (pci_space & 0x40000000)
+ res->flags |= IORESOURCE_PREFETCH;
+ res->start = cpu_addr;
+ break;
+ }
+ if (res != NULL) {
+ res->name = dev->full_name;
+ res->end = res->start + size - 1;
+ res->parent = NULL;
+ res->sibling = NULL;
+ res->child = NULL;
+ }
+ }
+
+ /* If there's an ISA hole and the pci_mem_offset is -not- matching
+ * the ISA hole offset, then we need to remove the ISA hole from
+ * the resource list for that brige
+ */
+ if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
+ unsigned int next = isa_hole + 1;
+ pr_info(" Removing ISA hole at 0x%016llx\n", isa_mb);
+ if (next < memno)
+ memmove(&hose->mem_resources[isa_hole],
+ &hose->mem_resources[next],
+ sizeof(struct resource) * (memno - next));
+ hose->mem_resources[--memno].flags = 0;
+ }
+}
+#endif
diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
index bb115de..33e8ead 100644
--- a/include/linux/of_pci.h
+++ b/include/linux/of_pci.h
@@ -11,4 +11,8 @@ struct device_node;
struct device_node *of_pci_find_child_device(struct device_node *parent,
unsigned int devfn);

+struct pci_controller;
+void pci_process_bridge_OF_ranges(struct pci_controller *hose,
+ struct device_node *dev, int primary);
+
#endif
--
1.7.0.4

2013-04-16 15:06:13

by Jason Cooper

[permalink] [raw]
Subject: Re: [PATCH v7 0/3] of/pci: Provide common support for PCI DT parsing

On Tue, Apr 16, 2013 at 11:18:25AM +0100, Andrew Murray wrote:
> This patchset factors out duplicated code associated with parsing PCI
> DT "ranges" properties across the architectures and introduces a
> "ranges" parser. This parser "of_pci_range_parser" can be used directly
> by ARM host bridge drivers enabling them to obtain ranges from device
> trees.
>
> I've included the Reviewed-by and Tested-by's received from v5/v6 in this
> patchset, earlier versions of this patchset (v3) have been tested-by:
>
> Thierry Reding <[email protected]>
> Jingoo Han <[email protected]>
>
> I've tested that this patchset builds and runs on ARM and that it builds on
> PowerPC and x86_64.

Series replaces v6 in mvebu/drivers

thx,

Jason.

>
> Compared to the v6 sent by Andrew Murray, the following changes have
> been made in response to build errors/warnings:
>
> * Inclusion of linux/of_address.h in of_pci.c as suggested by Michal
> Simek to prevent compilation failures on Microblaze (and others) and his
> ack.
>
> * Use of externs, static inlines and a typo in linux/of_address.h in response
> to linker errors (multiple defination) on x86_64 as spotted by a kbuild test
> robot on (jcooper/linux.git mvebu/drivers)
>
> * Add EXPORT_SYMBOL_GPL to of_pci_range_parser function to be consistent
> with of_pci_process_ranges function

2013-04-18 13:44:10

by Grant Likely

[permalink] [raw]
Subject: Re: [PATCH v7 2/3] of/pci: Provide support for parsing PCI DT ranges property

On Tue, 16 Apr 2013 11:18:27 +0100, Andrew Murray <[email protected]> wrote:
> This patch factors out common implementation patterns to reduce overall kernel
> code and provide a means for host bridge drivers to directly obtain struct
> resources from the DT's ranges property without relying on architecture specific
> DT handling. This will make it easier to write archiecture independent host bridge
> drivers and mitigate against further duplication of DT parsing code.
>
> This patch can be used in the following way:
>
> struct of_pci_range_parser parser;
> struct of_pci_range range;
>
> if (of_pci_range_parser(&parser, np))
> ; //no ranges property
>
> for_each_of_pci_range(&parser, &range) {
>
> /*
> directly access properties of the address range, e.g.:
> range.pci_space, range.pci_addr, range.cpu_addr,
> range.size, range.flags
>
> alternatively obtain a struct resource, e.g.:
> struct resource res;
> of_pci_range_to_resource(&range, np, &res);
> */
> }
>
> Additionally the implementation takes care of adjacent ranges and merges them
> into a single range (as was the case with powerpc and microblaze).
>
> Signed-off-by: Andrew Murray <[email protected]>
> Signed-off-by: Liviu Dudau <[email protected]>
> Signed-off-by: Thomas Petazzoni <[email protected]>
> Reviewed-by: Rob Herring <[email protected]>
> Tested-by: Thomas Petazzoni <[email protected]>
> Tested-by: Linus Walleij <[email protected]>

Acked-by: Grant Likely <[email protected]>

But comments below...

> ---
> drivers/of/address.c | 67 ++++++++++++++++++++++++++
> drivers/of/of_pci.c | 113 ++++++++++++++++----------------------------
> include/linux/of_address.h | 46 ++++++++++++++++++
> 3 files changed, 154 insertions(+), 72 deletions(-)
>
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index 04da786..6eec70c 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -227,6 +227,73 @@ int of_pci_address_to_resource(struct device_node *dev, int bar,
> return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
> }
> EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
> +
> +int of_pci_range_parser(struct of_pci_range_parser *parser,
> + struct device_node *node)
> +{
> + const int na = 3, ns = 2;
> + int rlen;
> +
> + parser->node = node;
> + parser->pna = of_n_addr_cells(node);
> + parser->np = parser->pna + na + ns;
> +
> + parser->range = of_get_property(node, "ranges", &rlen);
> + if (parser->range == NULL)
> + return -ENOENT;
> +
> + parser->end = parser->range + rlen / sizeof(__be32);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(of_pci_range_parser);

"of_pci_range_parser_init" would be a clearer name

> +struct of_pci_range *of_pci_process_ranges(struct of_pci_range_parser *parser,
> + struct of_pci_range *range)

Similarly, "of_pci_range_parser_one" would be more consistent.

> +{
> + const int na = 3, ns = 2;
> +
> + if (!range)
> + return NULL;
> +
> + if (!parser->range || parser->range + parser->np > parser->end)
> + return NULL;
> +
> + range->pci_space = parser->range[0];
> + range->flags = of_bus_pci_get_flags(parser->range);
> + range->pci_addr = of_read_number(parser->range + 1, ns);
> + range->cpu_addr = of_translate_address(parser->node,
> + parser->range + na);
> + range->size = of_read_number(parser->range + parser->pna + na, ns);
> +
> + parser->range += parser->np;
> +
> + /* Now consume following elements while they are contiguous */
> + while (parser->range + parser->np <= parser->end) {
> + u32 flags, pci_space;
> + u64 pci_addr, cpu_addr, size;
> +
> + pci_space = be32_to_cpup(parser->range);
> + flags = of_bus_pci_get_flags(parser->range);
> + pci_addr = of_read_number(parser->range + 1, ns);
> + cpu_addr = of_translate_address(parser->node,
> + parser->range + na);
> + size = of_read_number(parser->range + parser->pna + na, ns);
> +
> + if (flags != range->flags)
> + break;
> + if (pci_addr != range->pci_addr + range->size ||
> + cpu_addr != range->cpu_addr + range->size)
> + break;
> +
> + range->size += size;
> + parser->range += parser->np;
> + }
> +
> + return range;
> +}
> +EXPORT_SYMBOL_GPL(of_pci_process_ranges);
> +
> #endif /* CONFIG_PCI */
>
> /*
> diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
> index 1626172..e5ab604 100644
> --- a/drivers/of/of_pci.c
> +++ b/drivers/of/of_pci.c
> @@ -2,6 +2,7 @@
> #include <linux/export.h>
> #include <linux/of.h>
> #include <linux/of_pci.h>
> +#include <linux/of_address.h>
> #include <asm/prom.h>
>
> #if defined(CONFIG_PPC32) || defined(CONFIG_PPC64) || defined(CONFIG_MICROBLAZE)
> @@ -82,67 +83,43 @@ EXPORT_SYMBOL_GPL(of_pci_find_child_device);
> void pci_process_bridge_OF_ranges(struct pci_controller *hose,
> struct device_node *dev, int primary)
> {
> - const u32 *ranges;
> - int rlen;
> - int pna = of_n_addr_cells(dev);
> - int np = pna + 5;
> int memno = 0, isa_hole = -1;
> - u32 pci_space;
> - unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
> unsigned long long isa_mb = 0;
> struct resource *res;
> + struct of_pci_range range;
> + struct of_pci_range_parser parser;
> + u32 res_type;
>
> pr_info("PCI host bridge %s %s ranges:\n",
> dev->full_name, primary ? "(primary)" : "");
>
> - /* Get ranges property */
> - ranges = of_get_property(dev, "ranges", &rlen);
> - if (ranges == NULL)
> + /* Check for ranges property */
> + if (of_pci_range_parser(&parser, dev))
> return;
>
> - /* Parse it */
> pr_debug("Parsing ranges property...\n");
> - while ((rlen -= np * 4) >= 0) {
> + for_each_of_pci_range(&parser, &range) {
> /* Read next ranges element */
> - pci_space = ranges[0];
> - pci_addr = of_read_number(ranges + 1, 2);
> - cpu_addr = of_translate_address(dev, ranges + 3);
> - size = of_read_number(ranges + pna + 3, 2);

Tip: the diff on this function would be a whole lot simpler if the
above locals were kept, but updated from the ranges structure. Not at
all a big problem, but it is something that makes changes like this
easier to review. The removal of the locals could also be split into a
separate patch to end up with the same result.

> -
> - pr_debug("pci_space: 0x%08x pci_addr:0x%016llx ",
> - pci_space, pci_addr);
> - pr_debug("cpu_addr:0x%016llx size:0x%016llx\n",
> - cpu_addr, size);
> -
> - ranges += np;
> + pr_debug("pci_space: 0x%08x pci_addr: 0x%016llx ",
> + range.pci_space, range.pci_addr);
> + pr_debug("cpu_addr: 0x%016llx size: 0x%016llx\n",
> + range.cpu_addr, range.size);

Nit: the patch changed whitespace on the pr_debug() statements, so even
though the first line of each is identical, they look different in the
patch.

>
> /* If we failed translation or got a zero-sized region
> * (some FW try to feed us with non sensical zero sized regions
> * such as power3 which look like some kind of attempt
> * at exposing the VGA memory hole)
> */
> - if (cpu_addr == OF_BAD_ADDR || size == 0)
> + if (range.cpu_addr == OF_BAD_ADDR || range.size == 0)
> continue;

Can this also be rolled into the parsing iterator?

>
> - /* Now consume following elements while they are contiguous */
> - for (; rlen >= np * sizeof(u32);
> - ranges += np, rlen -= np * 4) {
> - if (ranges[0] != pci_space)
> - break;
> - pci_next = of_read_number(ranges + 1, 2);
> - cpu_next = of_translate_address(dev, ranges + 3);
> - if (pci_next != pci_addr + size ||
> - cpu_next != cpu_addr + size)
> - break;
> - size += of_read_number(ranges + pna + 3, 2);
> - }
> -
> /* Act based on address space type */
> res = NULL;
> - switch ((pci_space >> 24) & 0x3) {
> - case 1: /* PCI IO space */
> + res_type = range.flags & IORESOURCE_TYPE_BITS;
> + if (res_type == IORESOURCE_IO) {

Why the change from switch() to an if/else if sequence?

But those are mostly nitpicks. If this is deferred to v3.10 then I would
suggest fixing them up and posting for another round of review.

g.

2013-04-18 13:45:44

by Grant Likely

[permalink] [raw]
Subject: Re: [PATCH v7 3/3] of/pci: mips: convert to common of_pci_range_parser

On Tue, 16 Apr 2013 11:18:28 +0100, Andrew Murray <[email protected]> wrote:
> This patch converts the pci_load_of_ranges function to use the new common
> of_pci_range_parser.
>
> Signed-off-by: Andrew Murray <[email protected]>
> Signed-off-by: Liviu Dudau <[email protected]>
> Reviewed-by: Rob Herring <[email protected]>

Looks okay to me, and thank you very much for doing the legwork to merge
the common code.

Reviewed-by: Grant Likely <[email protected]>