mlx4_core: Write MTTs from CPU instead with of WRITE_MTT FW command
Write MTT entries directly to ICM from the driver (eliminating use of
WRITE_MTT command). This reduces the number of FW commands needed to
register an MR by at least a factor of 2 and speeds up memory
registration significantly. This code will also be used to implement
FMRs.
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/net/mlx4/main.c b/drivers/net/mlx4/main.c
index ed7e8d7..478b3ba 100644
--- a/drivers/net/mlx4/main.c
+++ b/drivers/net/mlx4/main.c
@@ -300,6 +300,17 @@
goto err_unmap_cmpt;
}
+ /*
+ * Reserved MTT entries must be aligned up to a cacheline
+ * boundary, since the FW will write to them, while the driver
+ * writes to all other MTT entries. (The variable
+ * dev->caps.mtt_entry_sz below is really the MTT segment
+ * size, not the raw entry size)
+ */
+ dev->caps.reserved_mtts =
+ ALIGN(dev->caps.reserved_mtts * dev->caps.mtt_entry_sz,
+ dma_get_cache_alignment()) / dev->caps.mtt_entry_sz;
+
err = mlx4_init_icm_table(dev, &priv->mr_table.mtt_table,
init_hca->mtt_base,
dev->caps.mtt_entry_sz,