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, 7 deletions

diff --git a/sys/dev/aacraid/aacraid_pci.c b/sys/dev/aacraid/aacraid_pci.c
index 6204fdf..0b91f2d 100644
--- a/sys/dev/aacraid/aacraid_pci.c
+++ b/sys/dev/aacraid/aacraid_pci.c
@@ -169,18 +169,12 @@ aacraid_pci_attach(device_t dev)
 	/* 
 	 * Verify that the adapter is correctly set up in PCI space.
 	 */
-	command = pci_read_config(sc->aac_dev, PCIR_COMMAND, 2);
-	command |= PCIM_CMD_BUSMASTEREN;
-	pci_write_config(dev, PCIR_COMMAND, command, 2);
+	pci_enable_busmaster(dev);
 	command = pci_read_config(sc->aac_dev, PCIR_COMMAND, 2);
 	if (!(command & PCIM_CMD_BUSMASTEREN)) {
 		device_printf(sc->aac_dev, "can't enable bus-master feature\n");
 		goto out;
 	}
-	if ((command & PCIM_CMD_MEMEN) == 0) {
-		device_printf(sc->aac_dev, "memory window not available\n");
-		goto out;
-	}
 
 	/* 
 	 * Detect the hardware interface version, set up the bus interface