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, 1 insertions, 3 deletions

diff --git a/sys/dev/asr/asr.c b/sys/dev/asr/asr.c
index 549ca1a..8909d0c 100644
--- a/sys/dev/asr/asr.c
+++ b/sys/dev/asr/asr.c
@@ -2428,9 +2428,7 @@ asr_attach(device_t dev)
 		return(ENXIO);
 	}
 	/* Enable if not formerly enabled */
-	pci_write_config(dev, PCIR_COMMAND,
-	    pci_read_config(dev, PCIR_COMMAND, sizeof(char)) |
-	    PCIM_CMD_MEMEN | PCIM_CMD_BUSMASTEREN, sizeof(char));
+	pci_enable_busmaster(dev);
 
 	sc->ha_pciBusNum = pci_get_bus(dev);
 	sc->ha_pciDeviceNum = (pci_get_slot(dev) << 3) | pci_get_function(dev);