IB/mthca: Avoid alignment traps when writing doorbells

Architectures such as ia64 see alignment traps when doing a 64-bit 
read from __be32 doorbell[2] arrays to do doorbell writes in 
mthca_write64().  Fix this by just passing the two halves of the 
doorbell value into mthca_write64().  This actually improves the 
generated code by allowing the compiler to see what's going on better.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 3 insertions, 18 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_eq.c b/drivers/infiniband/hw/mthca/mthca_eq.c
index 8592b26dc4e1..b29de51b7f35 100644
--- a/drivers/infiniband/hw/mthca/mthca_eq.c
+++ b/drivers/infiniband/hw/mthca/mthca_eq.c
@@ -173,11 +173,6 @@ static inline u64 async_mask(struct mthca_dev *dev)
 
 static inline void tavor_set_eq_ci(struct mthca_dev *dev, struct mthca_eq *eq, u32 ci)
 {
-        __be32 doorbell[2];
-
-        doorbell[0] = cpu_to_be32(MTHCA_EQ_DB_SET_CI | eq->eqn);
-        doorbell[1] = cpu_to_be32(ci & (eq->nent - 1));
-
         /*
          * This barrier makes sure that all updates to ownership bits
          * done by set_eqe_hw() hit memory before the consumer index
@@ -187,7 +182,7 @@ static inline void tavor_set_eq_ci(struct mthca_dev *dev, struct mthca_eq *eq, u
          * having set_eqe_hw() overwrite the owner field.
          */
         wmb();
-        mthca_write64(doorbell,
+        mthca_write64(MTHCA_EQ_DB_SET_CI | eq->eqn, ci & (eq->nent - 1),
                       dev->kar + MTHCA_EQ_DOORBELL,
                       MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock));
 }
@@ -212,12 +207,7 @@ static inline void set_eq_ci(struct mthca_dev *dev, struct mthca_eq *eq, u32 ci)
 
 static inline void tavor_eq_req_not(struct mthca_dev *dev, int eqn)
 {
-        __be32 doorbell[2];
-
-        doorbell[0] = cpu_to_be32(MTHCA_EQ_DB_REQ_NOT | eqn);
-        doorbell[1] = 0;
-
-        mthca_write64(doorbell,
+        mthca_write64(MTHCA_EQ_DB_REQ_NOT | eqn, 0,
                       dev->kar + MTHCA_EQ_DOORBELL,
                       MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock));
 }
@@ -230,12 +220,7 @@ static inline void arbel_eq_req_not(struct mthca_dev *dev, u32 eqn_mask)
 static inline void disarm_cq(struct mthca_dev *dev, int eqn, int cqn)
 {
         if (!mthca_is_memfree(dev)) {
-                __be32 doorbell[2];
-
-                doorbell[0] = cpu_to_be32(MTHCA_EQ_DB_DISARM_CQ | eqn);
-                doorbell[1] = cpu_to_be32(cqn);
-
-                mthca_write64(doorbell,
+                mthca_write64(MTHCA_EQ_DB_DISARM_CQ | eqn, cqn,
                               dev->kar + MTHCA_EQ_DOORBELL,
                               MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock));
         }