IB/ipath: Fix maximum MTU reporting
Although our chip supports 4K MTUs, our driver doesn't yet support
this feature, so limit the maximum MTU to 2K until we get support for
4K MTUs implemented.
Signed-off-by: Robert Walsh <robert.walsh@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/ipath/ipath_fs.c b/drivers/infiniband/hw/ipath/ipath_fs.c
index ebd5c7b..40cf1bc 100644
--- a/drivers/infiniband/hw/ipath/ipath_fs.c
+++ b/drivers/infiniband/hw/ipath/ipath_fs.c
@@ -257,9 +257,14 @@
/* Notimpl InitType (actually, an SMA decision) */
/* VLHighLimit is 0 (only one VL) */
; /* VLArbitrationHighCap is 0 (only one VL) */
+ /*
+ * Note: the chips support a maximum MTU of 4096, but the driver
+ * hasn't implemented this feature yet, so set the maximum
+ * to 2048.
+ */
portinfo[10] = /* VLArbitrationLowCap is 0 (only one VL) */
/* InitTypeReply is SMA decision */
- (5 << 16) /* MTUCap 4096 */
+ (4 << 16) /* MTUCap 2048 */
| (7 << 13) /* VLStallCount */
| (0x1f << 8) /* HOQLife */
| (1 << 4)
diff --git a/drivers/infiniband/hw/ipath/ipath_init_chip.c b/drivers/infiniband/hw/ipath/ipath_init_chip.c
index ee83934..bdfda62 100644
--- a/drivers/infiniband/hw/ipath/ipath_init_chip.c
+++ b/drivers/infiniband/hw/ipath/ipath_init_chip.c
@@ -310,7 +310,12 @@
val = ipath_read_kreg64(dd, dd->ipath_kregs->kr_sendpiosize);
dd->ipath_piosize2k = val & ~0U;
dd->ipath_piosize4k = val >> 32;
- dd->ipath_ibmtu = 4096; /* default to largest legal MTU */
+ /*
+ * Note: the chips support a maximum MTU of 4096, but the driver
+ * hasn't implemented this feature yet, so set the initial value
+ * to 2048.
+ */
+ dd->ipath_ibmtu = 2048;
val = ipath_read_kreg64(dd, dd->ipath_kregs->kr_sendpiobufcnt);
dd->ipath_piobcnt2k = val & ~0U;
dd->ipath_piobcnt4k = val >> 32;
diff --git a/drivers/infiniband/hw/ipath/ipath_mad.c b/drivers/infiniband/hw/ipath/ipath_mad.c
index 25908b0..2e9e161 100644
--- a/drivers/infiniband/hw/ipath/ipath_mad.c
+++ b/drivers/infiniband/hw/ipath/ipath_mad.c
@@ -292,7 +292,12 @@
/* pip->vl_arb_high_cap; // only one VL */
/* pip->vl_arb_low_cap; // only one VL */
/* InitTypeReply = 0 */
- pip->inittypereply_mtucap = IB_MTU_4096;
+ /*
+ * Note: the chips support a maximum MTU of 4096, but the driver
+ * hasn't implemented this feature yet, so set the maximum value
+ * to 2048.
+ */
+ pip->inittypereply_mtucap = IB_MTU_2048;
// HCAs ignore VLStallCount and HOQLife
/* pip->vlstallcnt_hoqlife; */
pip->operationalvl_pei_peo_fpi_fpo = 0x10; /* OVLs = 1 */
diff --git a/drivers/infiniband/hw/ipath/ipath_qp.c b/drivers/infiniband/hw/ipath/ipath_qp.c
index bfef08e..9e07abb 100644
--- a/drivers/infiniband/hw/ipath/ipath_qp.c
+++ b/drivers/infiniband/hw/ipath/ipath_qp.c
@@ -507,8 +507,13 @@
attr->port_num > ibqp->device->phys_port_cnt)
goto inval;
+ /*
+ * Note: the chips support a maximum MTU of 4096, but the driver
+ * hasn't implemented this feature yet, so don't allow Path MTU
+ * values greater than 2048.
+ */
if (attr_mask & IB_QP_PATH_MTU)
- if (attr->path_mtu > IB_MTU_4096)
+ if (attr->path_mtu > IB_MTU_2048)
goto inval;
if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
diff --git a/drivers/infiniband/hw/ipath/ipath_verbs.c b/drivers/infiniband/hw/ipath/ipath_verbs.c
index bb70845..980b64a 100644
--- a/drivers/infiniband/hw/ipath/ipath_verbs.c
+++ b/drivers/infiniband/hw/ipath/ipath_verbs.c
@@ -1051,7 +1051,12 @@
props->max_vl_num = 1; /* VLCap = VL0 */
props->init_type_reply = 0;
- props->max_mtu = IB_MTU_4096;
+ /*
+ * Note: the chips support a maximum MTU of 4096, but the driver
+ * hasn't implemented this feature yet, so set the maximum value
+ * to 2048.
+ */
+ props->max_mtu = IB_MTU_2048;
switch (dev->dd->ipath_ibmtu) {
case 4096:
mtu = IB_MTU_4096;