NTB: add new parameter to peer_db_addr() db_bit and db_data

NTB door bell usage depends on NTB hardware.

ex: intel NTB gen1 has one peer door bell register which can be controlled
by the bitmap writen to it, while Intel NTB gen3 has a registers
per door bell and the data trigering the each door bell is always 1.

therefore exposing only peer door bell address forcing the user
to be aware of such low level details

Signed-off-by: Leonid Ravich <Leonid.Ravich@emc.com>
Acked-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Allen Hubbe <allenbh@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

1 files changed, 7 insertions, 3 deletions

diff --git a/include/linux/ntb.h b/include/linux/ntb.h
index 181d16601dd9..56a92e3ae3ae 100644
--- a/include/linux/ntb.h
+++ b/include/linux/ntb.h
@@ -296,7 +296,8 @@ struct ntb_dev_ops {
         int (*db_clear_mask)(struct ntb_dev *ntb, u64 db_bits);
 
         int (*peer_db_addr)(struct ntb_dev *ntb,
-                            phys_addr_t *db_addr, resource_size_t *db_size);
+                            phys_addr_t *db_addr, resource_size_t *db_size,
+                                u64 *db_data, int db_bit);
         u64 (*peer_db_read)(struct ntb_dev *ntb);
         int (*peer_db_set)(struct ntb_dev *ntb, u64 db_bits);
         int (*peer_db_clear)(struct ntb_dev *ntb, u64 db_bits);
@@ -1078,6 +1079,8 @@ static inline int ntb_db_clear_mask(struct ntb_dev *ntb, u64 db_bits)
  * @ntb:        NTB device context.
  * @db_addr:    OUT - The address of the peer doorbell register.
  * @db_size:    OUT - The number of bytes to write the peer doorbell register.
+ * @db_data:    OUT - The data of peer doorbell register
+ * @db_bit:             door bell bit number
  *
  * Return the address of the peer doorbell register.  This may be used, for
  * example, by drivers that offload memory copy operations to a dma engine.
@@ -1091,12 +1094,13 @@ static inline int ntb_db_clear_mask(struct ntb_dev *ntb, u64 db_bits)
  */
 static inline int ntb_peer_db_addr(struct ntb_dev *ntb,
                                    phys_addr_t *db_addr,
-                                   resource_size_t *db_size)
+                                   resource_size_t *db_size,
+                                   u64 *db_data, int db_bit)
 {
         if (!ntb->ops->peer_db_addr)
                 return -EINVAL;
 
-        return ntb->ops->peer_db_addr(ntb, db_addr, db_size);
+        return ntb->ops->peer_db_addr(ntb, db_addr, db_size, db_data, db_bit);
 }
 
 /**