IB/mthca: fix QP size limits for mem-free HCAs

Unlike tavor, the max work queue size is an exact power of 2 for arbel
mode, despite what the documentation (of the QUERY_DEV_LIM firmware
command) says.  Without this patch, on Arbel, we can start with a QP
of a valid size and get above the reported limit after rounding to the
next power of two.

Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

diff --git a/drivers/infiniband/hw/mthca/mthca_cmd.c b/drivers/infiniband/hw/mthca/mthca_cmd.c
index 9ed3458..22ac72b 100644 (file)
--- a/drivers/infiniband/hw/mthca/mthca_cmd.c
+++ b/drivers/infiniband/hw/mthca/mthca_cmd.c
@@ -937,10 +937,6 @@ int mthca_QUERY_DEV_LIM(struct mthca_dev *dev,
        if (err)
                goto out;
 
-       MTHCA_GET(field, outbox, QUERY_DEV_LIM_MAX_SRQ_SZ_OFFSET);
-       dev_lim->max_srq_sz = (1 << field) - 1;
-       MTHCA_GET(field, outbox, QUERY_DEV_LIM_MAX_QP_SZ_OFFSET);
-       dev_lim->max_qp_sz = (1 << field) - 1;
        MTHCA_GET(field, outbox, QUERY_DEV_LIM_RSVD_QP_OFFSET);
        dev_lim->reserved_qps = 1 << (field & 0xf);
        MTHCA_GET(field, outbox, QUERY_DEV_LIM_MAX_QP_OFFSET);
@@ -1056,6 +1052,10 @@ int mthca_QUERY_DEV_LIM(struct mthca_dev *dev,
        mthca_dbg(dev, "Flags: %08x\n", dev_lim->flags);
 
        if (mthca_is_memfree(dev)) {
+               MTHCA_GET(field, outbox, QUERY_DEV_LIM_MAX_SRQ_SZ_OFFSET);
+               dev_lim->max_srq_sz = 1 << field;
+               MTHCA_GET(field, outbox, QUERY_DEV_LIM_MAX_QP_SZ_OFFSET);
+               dev_lim->max_qp_sz = 1 << field;
                MTHCA_GET(field, outbox, QUERY_DEV_LIM_RSZ_SRQ_OFFSET);
                dev_lim->hca.arbel.resize_srq = field & 1;
                MTHCA_GET(field, outbox, QUERY_DEV_LIM_MAX_SG_RQ_OFFSET);
@@ -1087,6 +1087,10 @@ int mthca_QUERY_DEV_LIM(struct mthca_dev *dev,
                mthca_dbg(dev, "Max ICM size %lld MB\n",
                          (unsigned long long) dev_lim->hca.arbel.max_icm_sz >> 20);
        } else {
+               MTHCA_GET(field, outbox, QUERY_DEV_LIM_MAX_SRQ_SZ_OFFSET);
+               dev_lim->max_srq_sz = (1 << field) - 1;
+               MTHCA_GET(field, outbox, QUERY_DEV_LIM_MAX_QP_SZ_OFFSET);
+               dev_lim->max_qp_sz = (1 << field) - 1;
                MTHCA_GET(field, outbox, QUERY_DEV_LIM_MAX_AV_OFFSET);
                dev_lim->hca.tavor.max_avs = 1 << (field & 0x3f);
                dev_lim->mpt_entry_sz = MTHCA_MPT_ENTRY_SIZE;