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, 5 insertions, 7 deletions

diff --git a/sys/dev/isp/isp_pci.c b/sys/dev/isp/isp_pci.c
index 795f432..782178c 100644
--- a/sys/dev/isp/isp_pci.c
+++ b/sys/dev/isp/isp_pci.c
@@ -706,13 +706,10 @@ isp_pci_attach(device_t dev)
 	pcs->irq = pcs->regs = NULL;
 	pcs->rgd = pcs->rtp = pcs->iqd = 0;
 
-	cmd = pci_read_config(dev, PCIR_COMMAND, 2);
-	if (cmd & m1) {
-		pcs->rtp = (m1 == PCIM_CMD_MEMEN)? SYS_RES_MEMORY : SYS_RES_IOPORT;
-		pcs->rgd = (m1 == PCIM_CMD_MEMEN)? MEM_MAP_REG : IO_MAP_REG;
-		pcs->regs = bus_alloc_resource_any(dev, pcs->rtp, &pcs->rgd, RF_ACTIVE);
-	}
-	if (pcs->regs == NULL && (cmd & m2)) {
+	pcs->rtp = (m1 == PCIM_CMD_MEMEN)? SYS_RES_MEMORY : SYS_RES_IOPORT;
+	pcs->rgd = (m1 == PCIM_CMD_MEMEN)? MEM_MAP_REG : IO_MAP_REG;
+	pcs->regs = bus_alloc_resource_any(dev, pcs->rtp, &pcs->rgd, RF_ACTIVE);
+	if (pcs->regs == NULL) {
 		pcs->rtp = (m2 == PCIM_CMD_MEMEN)? SYS_RES_MEMORY : SYS_RES_IOPORT;
 		pcs->rgd = (m2 == PCIM_CMD_MEMEN)? MEM_MAP_REG : IO_MAP_REG;
 		pcs->regs = bus_alloc_resource_any(dev, pcs->rtp, &pcs->rgd, RF_ACTIVE);
@@ -891,6 +888,7 @@ isp_pci_attach(device_t dev)
 	/*
 	 * Make sure that SERR, PERR, WRITE INVALIDATE and BUSMASTER are set.
 	 */
+	cmd = pci_read_config(dev, PCIR_COMMAND, 2);
 	cmd |= PCIM_CMD_SEREN | PCIM_CMD_PERRESPEN | PCIM_CMD_BUSMASTEREN | PCIM_CMD_INVEN;
 	if (IS_2300(isp)) {	/* per QLogic errata */
 		cmd &= ~PCIM_CMD_INVEN;