[RFC PATCH 06/16] PCI: Use u32 type to combine PCI domain and bus number

Yijing Wang
2014-11-17T09:45:19Z

Currently, we use int type for bus number in
pci_create_root_bus() and pci_scan_root_bus().
Because bus number is <= 255, so we could
change the bus number argument type to u32,
and combine PCI domain and bus number, we will
save the domain number in pci_host_bridge in
later patch, and eliminate the arch specific
pci_domain_nr().

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
---
drivers/pci/probe.c | 11 ++++++-----
include/linux/pci.h | 4 ++--
include/uapi/linux/pci.h | 3 +++
3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 623bfff..adf4d09 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1895,7 +1895,7 @@ void __weak pcibios_remove_bus(struct pci_bus *bus)
{
}

-struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
+struct pci_bus *pci_create_root_bus(struct device *parent, u32 db,
struct pci_ops *ops, void *sysdata, struct list_head *resources)
{
int error;
@@ -1906,6 +1906,7 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
resource_size_t offset;
char bus_addr[64];
char *fmt;
+ u8 bus = PCI_BUSNUM(db);

b = pci_alloc_bus(NULL);
if (!b)
@@ -2063,7 +2064,7 @@ void pci_bus_release_busn_res(struct pci_bus *b)
res, ret ? "can not be" : "is");
}

-struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
+struct pci_bus *pci_scan_root_bus(struct device *parent, u32 db,
struct pci_ops *ops, void *sysdata, struct list_head *resources)
{
struct pci_host_bridge_window *window;
@@ -2084,7 +2085,7 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
}
}

- b = pci_create_root_bus(parent, bus, ops, sysdata,
+ b = pci_create_root_bus(parent, db, ops, sysdata,
resources ? resources : &default_res);
if (!b)
return NULL;
@@ -2092,8 +2093,8 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
if (!found) {
dev_info(&b->dev,
"No busn resource found for root bus, will use [bus %02x-ff]\n",
- bus);
- pci_bus_insert_busn_res(b, bus, 255);
+ PCI_BUSNUM(db));
+ pci_bus_insert_busn_res(b, PCI_BUSNUM(db), 255);
}

max = pci_scan_child_bus(b);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 4daef65..8b11b38 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -767,13 +767,13 @@ void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
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);
-struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
+struct pci_bus *pci_create_root_bus(struct device *parent, u32 bus,
struct pci_ops *ops, void *sysdata,
struct list_head *resources);
int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int busmax);
int pci_bus_update_busn_res_end(struct pci_bus *b, int busmax);
void pci_bus_release_busn_res(struct pci_bus *b);
-struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
+struct pci_bus *pci_scan_root_bus(struct device *parent, u32 bus,
struct pci_ops *ops, void *sysdata,
struct list_head *resources);
struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
diff --git a/include/uapi/linux/pci.h b/include/uapi/linux/pci.h
index 3c292bc..89c6f15 100644
--- a/include/uapi/linux/pci.h
+++ b/include/uapi/linux/pci.h
@@ -30,6 +30,9 @@
#define PCI_DEVFN(slot, func) ((((slot) & 0x1f) << 3) | ((func) & 0x07))
#define PCI_SLOT(devfn) (((devfn) >> 3) & 0x1f)
#define PCI_FUNC(devfn) ((devfn) & 0x07)
+#define PCI_DOMAIN(db) ((db) >> 16)
+#define PCI_BUSNUM(db) ((db) & 0xffff)
+#define PCI_DOMBUS(domain, bus) (((domain) << 16) | (bus))

/* Ioctls for /proc/bus/pci/X/Y nodes. */
#define PCIIOC_BASE ('P' << 24 | 'C' << 16 | 'I' << 8)
--
1.7.1