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path: root/drivers/vme/bridges/vme_tsi148.c
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Diffstat (limited to 'drivers/vme/bridges/vme_tsi148.c')
-rw-r--r--drivers/vme/bridges/vme_tsi148.c85
1 files changed, 83 insertions, 2 deletions
diff --git a/drivers/vme/bridges/vme_tsi148.c b/drivers/vme/bridges/vme_tsi148.c
index f6385f7a66d9..880d9242e349 100644
--- a/drivers/vme/bridges/vme_tsi148.c
+++ b/drivers/vme/bridges/vme_tsi148.c
@@ -1263,12 +1263,55 @@ static ssize_t tsi148_master_read(struct vme_master_resource *image, void *buf,
u32 aspace, cycle, dwidth;
struct vme_bus_error *vme_err = NULL;
struct vme_bridge *tsi148_bridge;
+ void *addr = image->kern_base + offset;
+ unsigned int done = 0;
+ unsigned int count32;
tsi148_bridge = image->parent;
spin_lock(&image->lock);
- memcpy_fromio(buf, image->kern_base + offset, (unsigned int)count);
+ /* The following code handles VME address alignment. We cannot use
+ * memcpy_xxx directly here because it may cut small data transfers in
+ * to 8-bit cycles, thus making D16 cycle impossible.
+ * On the other hand, the bridge itself assures that the maximum data
+ * cycle configured for the transfer is used and splits it
+ * automatically for non-aligned addresses, so we don't want the
+ * overhead of needlessly forcing small transfers for the entire cycle.
+ */
+ if ((uintptr_t)addr & 0x1) {
+ *(u8 *)buf = ioread8(addr);
+ done += 1;
+ if (done == count)
+ goto out;
+ }
+ if ((uintptr_t)addr & 0x2) {
+ if ((count - done) < 2) {
+ *(u8 *)(buf + done) = ioread8(addr + done);
+ done += 1;
+ goto out;
+ } else {
+ *(u16 *)(buf + done) = ioread16(addr + done);
+ done += 2;
+ }
+ }
+
+ count32 = (count - done) & ~0x3;
+ if (count32 > 0) {
+ memcpy_fromio(buf + done, addr + done, count32);
+ done += count32;
+ }
+
+ if ((count - done) & 0x2) {
+ *(u16 *)(buf + done) = ioread16(addr + done);
+ done += 2;
+ }
+ if ((count - done) & 0x1) {
+ *(u8 *)(buf + done) = ioread8(addr + done);
+ done += 1;
+ }
+
+out:
retval = count;
if (!err_chk)
@@ -1301,6 +1344,9 @@ static ssize_t tsi148_master_write(struct vme_master_resource *image, void *buf,
int retval = 0, enabled;
unsigned long long vme_base, size;
u32 aspace, cycle, dwidth;
+ void *addr = image->kern_base + offset;
+ unsigned int done = 0;
+ unsigned int count32;
struct vme_bus_error *vme_err = NULL;
struct vme_bridge *tsi148_bridge;
@@ -1312,7 +1358,42 @@ static ssize_t tsi148_master_write(struct vme_master_resource *image, void *buf,
spin_lock(&image->lock);
- memcpy_toio(image->kern_base + offset, buf, (unsigned int)count);
+ /* Here we apply for the same strategy we do in master_read
+ * function in order to assure D16 cycle when required.
+ */
+ if ((uintptr_t)addr & 0x1) {
+ iowrite8(*(u8 *)buf, addr);
+ done += 1;
+ if (done == count)
+ goto out;
+ }
+ if ((uintptr_t)addr & 0x2) {
+ if ((count - done) < 2) {
+ iowrite8(*(u8 *)(buf + done), addr + done);
+ done += 1;
+ goto out;
+ } else {
+ iowrite16(*(u16 *)(buf + done), addr + done);
+ done += 2;
+ }
+ }
+
+ count32 = (count - done) & ~0x3;
+ if (count32 > 0) {
+ memcpy_toio(addr + done, buf + done, count32);
+ done += count32;
+ }
+
+ if ((count - done) & 0x2) {
+ iowrite16(*(u16 *)(buf + done), addr + done);
+ done += 2;
+ }
+ if ((count - done) & 0x1) {
+ iowrite8(*(u8 *)(buf + done), addr + done);
+ done += 1;
+ }
+
+out:
retval = count;
/*