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 ebd5c7bd2cdbec4680163237360ee88b12822b67..40cf1bc90d74bdff3313cb1e5e31770b813dc773 100644 (file)
--- a/drivers/infiniband/hw/ipath/ipath_fs.c
+++ b/drivers/infiniband/hw/ipath/ipath_fs.c
@@ -257,9 +257,14 @@ static ssize_t atomic_port_info_read(struct file *file, char __user *buf,
                /* 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 ee839346a3a4515b39f71325c0b4d7eb1dc6ed93..bdfda6221744a15df1f2b5e35826e05d60e688d0 100644 (file)
--- a/drivers/infiniband/hw/ipath/ipath_init_chip.c
+++ b/drivers/infiniband/hw/ipath/ipath_init_chip.c
@@ -310,7 +310,12 @@ static int init_chip_first(struct ipath_devdata *dd,
        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 25908b02fbe578f57fd6ee7128ea0c9b22169f32..2e9e161bfd0a60a77e34a5c70c87e7f1f886515b 100644 (file)
--- a/drivers/infiniband/hw/ipath/ipath_mad.c
+++ b/drivers/infiniband/hw/ipath/ipath_mad.c
@@ -292,7 +292,12 @@ static int recv_subn_get_portinfo(struct ib_smp *smp,
        /* 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 bfef08ecd342561b0d1272766564f43a700b1b2a..9e07abba8aa7743bd47bbf5dc9fb8b71f97cdd54 100644 (file)
--- a/drivers/infiniband/hw/ipath/ipath_qp.c
+++ b/drivers/infiniband/hw/ipath/ipath_qp.c
@@ -507,8 +507,13 @@ int ipath_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
                    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 bb70845279b8148aba4f2dcf4a769b9429efda48..980b64add321343b6b2b027bcc92a369373d52db 100644 (file)
--- a/drivers/infiniband/hw/ipath/ipath_verbs.c
+++ b/drivers/infiniband/hw/ipath/ipath_verbs.c
@@ -1051,7 +1051,12 @@ static int ipath_query_port(struct ib_device *ibdev,
        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;