From: David van Moolenbroek <david@minix3.org>
Date: Mon, 17 Nov 2014 19:19:36 +0000 (+0000)
Subject: rtl8139: enable bus mastering if needed
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/zpipe.c?a=commitdiff_plain;h=refs%2Fchanges%2F93%2F2893%2F1;p=minix.git

rtl8139: enable bus mastering if needed

This resolves #2.

Change-Id: Ie6736f0d5a713025f09c18de7042ba44fbb1b2f8
---

diff --git a/minix/drivers/net/rtl8139/rtl8139.c b/minix/drivers/net/rtl8139/rtl8139.c
index a71f46090..6318d2fd9 100644
--- a/minix/drivers/net/rtl8139/rtl8139.c
+++ b/minix/drivers/net/rtl8139/rtl8139.c
@@ -411,7 +411,7 @@ re_t *rep;
 int skip;
 {
 	int r, devind;
-	u16_t vid, did;
+	u16_t cr, vid, did;
 	u32_t bar;
 	u8_t ilr;
 #if VERBOSE
@@ -437,7 +437,13 @@ int skip;
 	printf("%s (%x/%x) at %s\n", dname, vid, did, pci_slot_name(devind));
 #endif
 	pci_reserve(devind);
-	/* printf("cr = 0x%x\n", pci_attr_r16(devind, PCI_CR)); */
+
+	/* Enable bus mastering if necessary. */
+	cr = pci_attr_r16(devind, PCI_CR);
+	/* printf("cr = 0x%x\n", cr); */
+	if (!(cr & PCI_CR_MAST_EN))
+		pci_attr_w16(devind, PCI_CR, cr | PCI_CR_MAST_EN);
+
 	bar= pci_attr_r32(devind, PCI_BAR) & 0xffffffe0;
 	if (bar < 0x400) {
 		panic("base address is not properly configured");