PCI: break out primary/secondary/subordinate for readability

No functional change; just add names for the primary/secondary/subordinate
bus numbers read from config space rather than repeatedly masking/shifting.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Bjorn Helgaas 2010-03-16 15:52:58 -06:00 committed by Jesse Barnes
parent 966f3a7570
commit 99ddd552fe

View File

@ -673,16 +673,20 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
u32 buses, i, j = 0;
u16 bctl;
u8 primary, secondary, subordinate;
int broken = 0;
pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
primary = buses & 0xFF;
secondary = (buses >> 8) & 0xFF;
subordinate = (buses >> 16) & 0xFF;
dev_dbg(&dev->dev, "scanning behind bridge, config %06x, pass %d\n",
buses & 0xffffff, pass);
dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
secondary, subordinate, pass);
/* Check if setup is sensible at all */
if (!pass &&
((buses & 0xff) != bus->number || ((buses >> 8) & 0xff) <= bus->number)) {
(primary != bus->number || secondary <= bus->number)) {
dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
broken = 1;
}
@ -693,15 +697,15 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
if ((buses & 0xffff00) && !pcibios_assign_all_busses() && !is_cardbus && !broken) {
unsigned int cmax, busnr;
if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
!is_cardbus && !broken) {
unsigned int cmax;
/*
* Bus already configured by firmware, process it in the first
* pass and just note the configuration.
*/
if (pass)
goto out;
busnr = (buses >> 8) & 0xFF;
/*
* If we already got to this bus through a different bridge,
@ -710,13 +714,13 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
* However, we continue to descend down the hierarchy and
* scan remaining child buses.
*/
child = pci_find_bus(pci_domain_nr(bus), busnr);
child = pci_find_bus(pci_domain_nr(bus), secondary);
if (!child) {
child = pci_add_new_bus(bus, dev, busnr);
child = pci_add_new_bus(bus, dev, secondary);
if (!child)
goto out;
child->primary = buses & 0xFF;
child->subordinate = (buses >> 16) & 0xFF;
child->primary = primary;
child->subordinate = subordinate;
child->bridge_ctl = bctl;
}