diff mbox

[3.8,45/67] VME: Correct read/write alignment algorithm

Message ID 1393872955-28810-46-git-send-email-kamal@canonical.com
State New
Headers show

Commit Message

Kamal Mostafa March 3, 2014, 6:55 p.m. UTC 
3.8.13.19 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Martyn Welch <martyn.welch@ge.com>

commit f0342e66b397947ed8c3eef8c37b5ca2d5b1bb50 upstream.

In order to ensure the correct width cycles on the VME bus, the VME bridge
drivers implement an algorithm to utilise the largest possible width reads and
writes whilst maintaining natural alignment constraints. The algorithm
currently looks at the start address rather than the current read/write address
when determining whether a 16-bit width cycle is required to get to 32-bit
alignment.  This results in incorrect alignment,

Reported-by: Jim Strouth <james.strouth@ge.com>
Tested-by: Jim Strouth <james.strouth@ge.com>
Signed-off-by: Martyn Welch <martyn.welch@ge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 drivers/vme/bridges/vme_ca91cx42.c | 4 ++--
 drivers/vme/bridges/vme_tsi148.c   | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)
diff mbox

Patch

diff --git a/drivers/vme/bridges/vme_ca91cx42.c b/drivers/vme/bridges/vme_ca91cx42.c
index 64bfea3..8ca1030 100644
--- a/drivers/vme/bridges/vme_ca91cx42.c
+++ b/drivers/vme/bridges/vme_ca91cx42.c
@@ -880,7 +880,7 @@  static ssize_t ca91cx42_master_read(struct vme_master_resource *image,
 		if (done == count)
 			goto out;
 	}
-	if ((uintptr_t)addr & 0x2) {
+	if ((uintptr_t)(addr + done) & 0x2) {
 		if ((count - done) < 2) {
 			*(u8 *)(buf + done) = ioread8(addr + done);
 			done += 1;
@@ -934,7 +934,7 @@  static ssize_t ca91cx42_master_write(struct vme_master_resource *image,
 		if (done == count)
 			goto out;
 	}
-	if ((uintptr_t)addr & 0x2) {
+	if ((uintptr_t)(addr + done) & 0x2) {
 		if ((count - done) < 2) {
 			iowrite8(*(u8 *)(buf + done), addr + done);
 			done += 1;
diff --git a/drivers/vme/bridges/vme_tsi148.c b/drivers/vme/bridges/vme_tsi148.c
index 9c1aa4d..6342406 100644
--- a/drivers/vme/bridges/vme_tsi148.c
+++ b/drivers/vme/bridges/vme_tsi148.c
@@ -1283,7 +1283,7 @@  static ssize_t tsi148_master_read(struct vme_master_resource *image, void *buf,
 		if (done == count)
 			goto out;
 	}
-	if ((uintptr_t)addr & 0x2) {
+	if ((uintptr_t)(addr + done) & 0x2) {
 		if ((count - done) < 2) {
 			*(u8 *)(buf + done) = ioread8(addr + done);
 			done += 1;
@@ -1365,7 +1365,7 @@  static ssize_t tsi148_master_write(struct vme_master_resource *image, void *buf,
 		if (done == count)
 			goto out;
 	}
-	if ((uintptr_t)addr & 0x2) {
+	if ((uintptr_t)(addr + done) & 0x2) {
 		if ((count - done) < 2) {
 			iowrite8(*(u8 *)(buf + done), addr + done);
 			done += 1;