On Mon, Nov 18, 2013 at 10:36 PM, Guo Chao <yan@xxxxxxxxxxxxxxxxxx> wrote:
> In resource assignment code, limits are exerted to restrict allocated
> resource range. However these limits are PCI address but compared to
> CPU address in the end. Translated them before comparing.
>
> We can't just use pcibios_bus_to_resource because the limits may not
> included in the host bridge window. Introduce a help function to
> do this translation, if address missed, return an approximate one.
>
> Signed-off-by: Guo Chao <yan@xxxxxxxxxxxxxxxxxx>
> ---
> drivers/pci/bus.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 63 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
> index fc1b740..532c0a4 100644
> --- a/drivers/pci/bus.c
> +++ b/drivers/pci/bus.c
> @@ -99,6 +99,64 @@ void pci_bus_remove_resources(struct pci_bus *bus)
> }
>
> /**
> + * pci_bus_to_resource
> + *
> + * Much like pcibios_bus_to_resource() except it takes a single address
> + * and returns an approximate one if target address is not included
> + * in the bridge window. The approximate address is smaller than required
> + * one is 'bound' is 1, larger than required one if 'bound' is 0.
> + */
> +static resource_size_t pci_bus_to_resource(struct pci_bus *bus, int flags,
> + int mask, resource_size_t addr, int bound)
> +{
> + struct pci_host_bridge *bridge;
> + struct pci_host_bridge_window *window, *match = NULL;
> + resource_size_t max = 0, min = -1;
> + resource_size_t offset = -1, start, end;
> +
> + while (bus->parent)
> + bus = bus->parent;
> +
> + bridge = to_pci_host_bridge(bus->bridge);
> +
> + list_for_each_entry(window, &bridge->windows, list) {
> + if ((flags ^ window->res->flags) & mask)
> + continue;
> +
> + start = window->res->start - window->offset;
> + end = window->res->end - window->offset;
> +
> + if (addr >= start && addr <= end) {
> + offset = window->offset;
> + break;
> + }
> +
> + if (bound && addr > end && end > max) {
> + max = end;
> + match = window;
> + } else if (!bound && addr < start && start < min) {
> + min = start;
> + match = window;
> + }
> + }
> +
> + if (offset == -1) {
> + /*
> + * Not even found the matched type. This may happen,
> + * for example, if try to translate IO address in a HB
> + * without IO window. Just return the original address,
> + * it will fail later anyway.
> + */
> + if (match == NULL)
> + return addr;
> +
> + return (bound ? max : min) + match->offset;
> + }
> +
> + return addr + offset;
> +}
that is confusing.
Can we use http://lkml.indiana.edu/hypermail/linux/kernel/1206.0/00437/pcibus_addr_converting_bus.patch
instead?
or as attached:
Subject: [PATCH] PCI: pcibus address to resource converting take bus directly
For allocating resource under bus path, we do have dev pass along, and we
could just use bus instead.
Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
---
drivers/pci/host-bridge.c | 34 +++++++++++++++++++++-------------
include/linux/pci.h | 3 +++
2 files changed, 24 insertions(+), 13 deletions(-)
Index: linux-2.6/drivers/pci/host-bridge.c
===================================================================
--- linux-2.6.orig/drivers/pci/host-bridge.c
+++ linux-2.6/drivers/pci/host-bridge.c
@@ -9,22 +9,19 @@
#include "pci.h"
-static struct pci_bus *find_pci_root_bus(struct pci_dev *dev)
+static struct pci_bus *find_pci_root_bus(struct pci_bus *bus)
{
- struct pci_bus *bus;
-
- bus = dev->bus;
while (bus->parent)
bus = bus->parent;
return bus;
}
-static struct pci_host_bridge *find_pci_host_bridge(struct pci_dev *dev)
+static struct pci_host_bridge *find_pci_host_bridge(struct pci_bus *bus)
{
- struct pci_bus *bus = find_pci_root_bus(dev);
+ struct pci_bus *root_bus = find_pci_root_bus(bus);
- return to_pci_host_bridge(bus->bridge);
+ return to_pci_host_bridge(root_bus->bridge);
}
void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
@@ -40,10 +37,11 @@ static bool resource_contains(struct res
return res1->start <= res2->start && res1->end >= res2->end;
}
-void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
- struct resource *res)
+void __pcibios_resource_to_bus(struct pci_bus *bus,
+ struct pci_bus_region *region,
+ struct resource *res)
{
- struct pci_host_bridge *bridge = find_pci_host_bridge(dev);
+ struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
struct pci_host_bridge_window *window;
resource_size_t offset = 0;
@@ -60,6 +58,11 @@ void pcibios_resource_to_bus(struct pci_
region->start = res->start - offset;
region->end = res->end - offset;
}
+void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
+ struct resource *res)
+{
+ __pcibios_resource_to_bus(dev->bus, region, res);
+}
EXPORT_SYMBOL(pcibios_resource_to_bus);
static bool region_contains(struct pci_bus_region *region1,
@@ -68,10 +71,10 @@ static bool region_contains(struct pci_b
return region1->start <= region2->start && region1->end >= region2->end;
}
-void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
- struct pci_bus_region *region)
+static void __pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
+ struct pci_bus_region *region)
{
- struct pci_host_bridge *bridge = find_pci_host_bridge(dev);
+ struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
struct pci_host_bridge_window *window;
resource_size_t offset = 0;
@@ -93,4 +96,9 @@ void pcibios_bus_to_resource(struct pci_
res->start = region->start + offset;
res->end = region->end + offset;
}
+void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
+ struct pci_bus_region *region)
+{
+ __pcibios_bus_to_resource(dev->bus, res, region);
+}
EXPORT_SYMBOL(pcibios_bus_to_resource);
Index: linux-2.6/include/linux/pci.h
===================================================================
--- linux-2.6.orig/include/linux/pci.h
+++ linux-2.6/include/linux/pci.h
@@ -792,6 +792,9 @@ void pci_fixup_cardbus(struct pci_bus *)
/* Generic PCI functions used internally */
+void __pcibios_resource_to_bus(struct pci_bus *bus,
+ struct pci_bus_region *region,
+ struct resource *res);
void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
struct resource *res);
void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
Subject: [PATCH] PCI: Add pcibios_bus_addr_to_res()
it takes addr and return converted address only.
Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
---
drivers/pci/host-bridge.c | 14 ++++++++++++++
include/linux/pci.h | 2 ++
2 files changed, 16 insertions(+)
Index: linux-2.6/drivers/pci/host-bridge.c
===================================================================
--- linux-2.6.orig/drivers/pci/host-bridge.c
+++ linux-2.6/drivers/pci/host-bridge.c
@@ -102,3 +102,17 @@ void pcibios_bus_to_resource(struct pci_
__pcibios_bus_to_resource(dev->bus, res, region);
}
EXPORT_SYMBOL(pcibios_bus_to_resource);
+
+resource_size_t pcibios_bus_addr_to_res(struct pci_bus *bus, int flags,
+ resource_size_t addr)
+{
+ struct pci_bus_region region;
+ struct resource r;
+
+ r.flags = flags;
+ region.start = addr;
+ region.end = addr;
+ __pcibios_bus_to_resource(bus, &r, ®ion);
+
+ return r.end;
+}
Index: linux-2.6/include/linux/pci.h
===================================================================
--- linux-2.6.orig/include/linux/pci.h
+++ linux-2.6/include/linux/pci.h
@@ -799,6 +799,8 @@ void pcibios_resource_to_bus(struct pci_
struct resource *res);
void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
struct pci_bus_region *region);
+resource_size_t pcibios_bus_addr_to_res(struct pci_bus *bus, int flags,
+ resource_size_t addr);
void pcibios_scan_specific_bus(int busn);
struct pci_bus *pci_find_bus(int domain, int busnr);
void pci_bus_add_devices(const struct pci_bus *bus);
