[src/trunk]: src/sys/dev/pci Explicitly enable bus masterling in case BIOS, U...

[msaitoh <msaitoh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/fb38a4ef3523
branches:  trunk
changeset: 838706:fb38a4ef3523
user:      msaitoh <msaitoh%NetBSD.org@localhost>
date:      Mon Jan 28 04:09:51 2019 +0000

description:
Explicitly enable bus masterling in case BIOS, UEFI or firmware don't enable
it. Might fix PR kern/53811.

diffstat:

 sys/dev/pci/ppb.c |  9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

diffs (30 lines):

diff -r 3a4cc2755262 -r fb38a4ef3523 sys/dev/pci/ppb.c
--- a/sys/dev/pci/ppb.c Mon Jan 28 03:37:52 2019 +0000
+++ b/sys/dev/pci/ppb.c Mon Jan 28 04:09:51 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ppb.c,v 1.65 2019/01/27 02:08:42 pgoyette Exp $        */
+/*     $NetBSD: ppb.c,v 1.66 2019/01/28 04:09:51 msaitoh Exp $ */
 
 /*
  * Copyright (c) 1996, 1998 Christopher G. Demetriou.  All rights reserved.
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ppb.c,v 1.65 2019/01/27 02:08:42 pgoyette Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ppb.c,v 1.66 2019/01/28 04:09:51 msaitoh Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_ppb.h"
@@ -358,6 +358,11 @@
        }
 #endif /* PPB_USEINTR */
 
+       /* Enable bus master. */
+       reg = pci_conf_read(pc, pa->pa_tag, PCI_COMMAND_STATUS_REG);
+       pci_conf_write(pc, pa->pa_tag, PCI_COMMAND_STATUS_REG,
+           reg | PCI_COMMAND_MASTER_ENABLE);
+
        if (!pmf_device_register(self, ppb_suspend, ppb_resume))
                aprint_error_dev(self, "couldn't establish power handler\n");