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>
diff --git a/drivers/infiniband/hw/mthca/mthca_cq.c b/drivers/infiniband/hw/mthca/mthca_cq.c
index be6e1e0..6bd9f13 100644
--- a/drivers/infiniband/hw/mthca/mthca_cq.c
+++ b/drivers/infiniband/hw/mthca/mthca_cq.c
@@ -204,16 +204,11 @@
static inline void update_cons_index(struct mthca_dev *dev, struct mthca_cq *cq,
int incr)
{
- __be32 doorbell[2];
-
if (mthca_is_memfree(dev)) {
*cq->set_ci_db = cpu_to_be32(cq->cons_index);
wmb();
} else {
- doorbell[0] = cpu_to_be32(MTHCA_TAVOR_CQ_DB_INC_CI | cq->cqn);
- doorbell[1] = cpu_to_be32(incr - 1);
-
- mthca_write64(doorbell,
+ mthca_write64(MTHCA_TAVOR_CQ_DB_INC_CI | cq->cqn, incr - 1,
dev->kar + MTHCA_CQ_DOORBELL,
MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock));
/*
@@ -731,17 +726,12 @@
int mthca_tavor_arm_cq(struct ib_cq *cq, enum ib_cq_notify_flags flags)
{
- __be32 doorbell[2];
+ u32 dbhi = ((flags & IB_CQ_SOLICITED_MASK) == IB_CQ_SOLICITED ?
+ MTHCA_TAVOR_CQ_DB_REQ_NOT_SOL :
+ MTHCA_TAVOR_CQ_DB_REQ_NOT) |
+ to_mcq(cq)->cqn;
- doorbell[0] = cpu_to_be32(((flags & IB_CQ_SOLICITED_MASK) ==
- IB_CQ_SOLICITED ?
- MTHCA_TAVOR_CQ_DB_REQ_NOT_SOL :
- MTHCA_TAVOR_CQ_DB_REQ_NOT) |
- to_mcq(cq)->cqn);
- doorbell[1] = (__force __be32) 0xffffffff;
-
- mthca_write64(doorbell,
- to_mdev(cq->device)->kar + MTHCA_CQ_DOORBELL,
+ mthca_write64(dbhi, 0xffffffff, to_mdev(cq->device)->kar + MTHCA_CQ_DOORBELL,
MTHCA_GET_DOORBELL_LOCK(&to_mdev(cq->device)->doorbell_lock));
return 0;
@@ -750,19 +740,16 @@
int mthca_arbel_arm_cq(struct ib_cq *ibcq, enum ib_cq_notify_flags flags)
{
struct mthca_cq *cq = to_mcq(ibcq);
- __be32 doorbell[2];
- u32 sn;
- __be32 ci;
+ __be32 db_rec[2];
+ u32 dbhi;
+ u32 sn = cq->arm_sn & 3;
- sn = cq->arm_sn & 3;
- ci = cpu_to_be32(cq->cons_index);
+ db_rec[0] = cpu_to_be32(cq->cons_index);
+ db_rec[1] = cpu_to_be32((cq->cqn << 8) | (2 << 5) | (sn << 3) |
+ ((flags & IB_CQ_SOLICITED_MASK) ==
+ IB_CQ_SOLICITED ? 1 : 2));
- doorbell[0] = ci;
- doorbell[1] = cpu_to_be32((cq->cqn << 8) | (2 << 5) | (sn << 3) |
- ((flags & IB_CQ_SOLICITED_MASK) ==
- IB_CQ_SOLICITED ? 1 : 2));
-
- mthca_write_db_rec(doorbell, cq->arm_db);
+ mthca_write_db_rec(db_rec, cq->arm_db);
/*
* Make sure that the doorbell record in host memory is
@@ -770,14 +757,12 @@
*/
wmb();
- doorbell[0] = cpu_to_be32((sn << 28) |
- ((flags & IB_CQ_SOLICITED_MASK) == IB_CQ_SOLICITED ?
- MTHCA_ARBEL_CQ_DB_REQ_NOT_SOL :
- MTHCA_ARBEL_CQ_DB_REQ_NOT) |
- cq->cqn);
- doorbell[1] = ci;
+ dbhi = (sn << 28) |
+ ((flags & IB_CQ_SOLICITED_MASK) == IB_CQ_SOLICITED ?
+ MTHCA_ARBEL_CQ_DB_REQ_NOT_SOL :
+ MTHCA_ARBEL_CQ_DB_REQ_NOT) | cq->cqn;
- mthca_write64(doorbell,
+ mthca_write64(dbhi, cq->cons_index,
to_mdev(ibcq->device)->kar + MTHCA_CQ_DOORBELL,
MTHCA_GET_DOORBELL_LOCK(&to_mdev(ibcq->device)->doorbell_lock));