Update PCI drivers to no longer look at the MEMIO-enabled bit in the PCI

command register.  The lazy BAR allocation code in FreeBSD sometimes
disables this bit when it detects a range conflict, and will re-enable
it on demand when a driver allocates the BAR.  Thus, the bit is no longer
a reliable indication of capability, and should not be checked.  This
results in the elimination of a lot of code from drivers, and also gives
the opportunity to simplify a lot of drivers to use a helper API to set
the busmaster enable bit.

This changes fixes some recent reports of disk controllers and their
associated drives/enclosures disappearing during boot.

Submitted by:	jhb
Reviewed by:	jfv, marius, achadd, achim
MFC after:	1 day

1 files changed, 2 insertions, 2 deletions

diff --git a/sys/pci/ncr.c b/sys/pci/ncr.c
index 2dfba6128c3d..d13769cc6313 100644
--- a/sys/pci/ncr.c
+++ b/sys/pci/ncr.c
@@ -3622,8 +3622,8 @@ ncr_attach (device_t dev)
 			pci_write_config(dev, PCIR_CACHELNSZ, cachelnsz, 1);
 		}
 
-		if (!(command & (1<<4))) {
-			command |= (1<<4);
+		if (!(command & PCIM_CMD_MWRICEN)) {
+			command |= PCIM_CMD_MWRICEN;
 			printf("%s: setting PCI command write and invalidate.\n",
 				ncr_name(np));
 			pci_write_config(dev, PCIR_COMMAND, command, 2);