[PATCH] pci: only call pci_restore_bars at boot

Certain (SGI?) ia64 boxes object to having their PCI BARs
restored unless absolutely necessary. This patch restricts calling
pci_restore_bars from pci_set_power_state unless the current state
is PCI_UNKNOWN, the actual (i.e. physical) state of the device is
PCI_D3hot, and the device indicates that it will lose its configuration
when transitioning to PCI_D0.

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
John W. Linville 2005-09-14 09:52:42 -04:00 committed by Linus Torvalds
parent 186051d704
commit 32a3658533

View file

@ -309,17 +309,25 @@ pci_set_power_state(struct pci_dev *dev, pci_power_t state)
pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
/* If we're in D3, force entire word to 0.
/* If we're (effectively) in D3, force entire word to 0.
* This doesn't affect PME_Status, disables PME_En, and
* sets PowerState to 0.
*/
if (dev->current_state >= PCI_D3hot) {
if (!(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
switch (dev->current_state) {
case PCI_UNKNOWN: /* Boot-up */
if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
&& !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
need_restore = 1;
/* Fall-through: force to D0 */
case PCI_D3hot:
case PCI_D3cold:
case PCI_POWER_ERROR:
pmcsr = 0;
} else {
break;
default:
pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
pmcsr |= state;
break;
}
/* enter specified state */