summaryrefslogtreecommitdiffstats
path: root/drivers/pci/bus.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/pci/bus.c')
-rw-r--r--drivers/pci/bus.c81
1 files changed, 5 insertions, 76 deletions
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 003170ea2e39..69546e9213dd 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -64,77 +64,6 @@ void pci_bus_remove_resources(struct pci_bus *bus)
}
}
-static bool pci_bus_resource_better(struct resource *res1, bool pos1,
- struct resource *res2, bool pos2)
-{
- /* If exactly one is positive decode, always prefer that one */
- if (pos1 != pos2)
- return pos1 ? true : false;
-
- /* Prefer the one that contains the highest address */
- if (res1->end != res2->end)
- return (res1->end > res2->end) ? true : false;
-
- /* Otherwise, prefer the one with highest "center of gravity" */
- if (res1->start != res2->start)
- return (res1->start > res2->start) ? true : false;
-
- /* Otherwise, choose one arbitrarily (but consistently) */
- return (res1 > res2) ? true : false;
-}
-
-static bool pci_bus_resource_positive(struct pci_bus *bus, struct resource *res)
-{
- struct pci_bus_resource *bus_res;
-
- /*
- * This relies on the fact that pci_bus.resource[] refers to P2P or
- * CardBus bridge base/limit registers, which are always positively
- * decoded. The pci_bus.resources list contains host bridge or
- * subtractively decoded resources.
- */
- list_for_each_entry(bus_res, &bus->resources, list) {
- if (bus_res->res == res)
- return (bus_res->flags & PCI_SUBTRACTIVE_DECODE) ?
- false : true;
- }
- return true;
-}
-
-/*
- * Find the next-best bus resource after the cursor "res". If the cursor is
- * NULL, return the best resource. "Best" means that we prefer positive
- * decode regions over subtractive decode, then those at higher addresses.
- */
-static struct resource *pci_bus_find_resource_prev(struct pci_bus *bus,
- unsigned int type,
- struct resource *res)
-{
- bool res_pos, r_pos, prev_pos = false;
- struct resource *r, *prev = NULL;
- int i;
-
- res_pos = pci_bus_resource_positive(bus, res);
- pci_bus_for_each_resource(bus, r, i) {
- if (!r)
- continue;
-
- if ((r->flags & IORESOURCE_TYPE_BITS) != type)
- continue;
-
- r_pos = pci_bus_resource_positive(bus, r);
- if (!res || pci_bus_resource_better(res, res_pos, r, r_pos)) {
- if (!prev || pci_bus_resource_better(r, r_pos,
- prev, prev_pos)) {
- prev = r;
- prev_pos = r_pos;
- }
- }
- }
-
- return prev;
-}
-
/**
* pci_bus_alloc_resource - allocate a resource from a parent bus
* @bus: PCI bus
@@ -160,10 +89,9 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
resource_size_t),
void *alignf_data)
{
- int ret = -ENOMEM;
+ int i, ret = -ENOMEM;
struct resource *r;
resource_size_t max = -1;
- unsigned int type = res->flags & IORESOURCE_TYPE_BITS;
type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
@@ -171,9 +99,10 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
if (!(res->flags & IORESOURCE_MEM_64))
max = PCIBIOS_MAX_MEM_32;
- /* Look for space at highest addresses first */
- r = pci_bus_find_resource_prev(bus, type, NULL);
- for ( ; r; r = pci_bus_find_resource_prev(bus, type, r)) {
+ pci_bus_for_each_resource(bus, r, i) {
+ if (!r)
+ continue;
+
/* type_mask must match */
if ((res->flags ^ r->flags) & type_mask)
continue;
OpenPOWER on IntegriCloud