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, 0 insertions, 14 deletions

diff --git a/sys/dev/an/if_an_pci.c b/sys/dev/an/if_an_pci.c
index fe3467d..1c3032c 100644
--- a/sys/dev/an/if_an_pci.c
+++ b/sys/dev/an/if_an_pci.c
@@ -141,7 +141,6 @@ static int
 an_attach_pci(dev)
 	device_t		dev;
 {
-	u_int32_t		command;
 	struct an_softc		*sc;
 	int 			flags, error = 0;
 
@@ -153,19 +152,6 @@ an_attach_pci(dev)
 		sc->mpi350 = 1;
 		sc->port_rid = PCIR_BAR(0);
 	} else {
-		/*
-		 * Map control/status registers.
-	 	 */
-		command = pci_read_config(dev, PCIR_COMMAND, 4);
-		command |= PCIM_CMD_PORTEN;
-		pci_write_config(dev, PCIR_COMMAND, command, 4);
-		command = pci_read_config(dev, PCIR_COMMAND, 4);
-
-		if (!(command & PCIM_CMD_PORTEN)) {
-			device_printf(dev, "failed to enable I/O ports!\n");
-			error = ENXIO;
-			goto fail;
-		}
 		sc->port_rid = AN_PCI_LOIO;
 	}
 	error = an_alloc_port(dev, sc->port_rid, 1);