bna: MSGQ Implementation

Change details:
 - Currently modules communicate with the FW using 32 byte command and
   response register. This limits the size of the command and response
   messages exchanged with the FW to 32 bytes. We need a mechanism to
   exchange the comamnds and responses exchange with FW that exceeds 32 bytes.

 - MSGQ implementation provides that facility. It removes the assumption that
   command/response queue size is precisely calculated to accommodate all
   concurrent FW commands/responses. The queue depth is made variable now, defined
   by a macro. A waiting command list is implemented to hold all the commands
   when there is no place in the command queue. Callback is implemented for
   each command entry to invoke the module posting the command, when there is
   space in the command queue and the command was finally posted to the queue.
   Module/Object information is embedded in the response for tracking purpose.

Signed-off-by: Rasesh Mody <rmody@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/brocade/bna/Makefile

@@ -6,6 +6,7 @@
 obj-$(CONFIG_BNA) += bna.o
 
 bna-objs := bnad.o bnad_ethtool.o bna_ctrl.o bna_txrx.o
-bna-objs += bfa_ioc.o bfa_ioc_ct.o bfa_cee.o cna_fwimg.o
+bna-objs += bfa_msgq.o bfa_ioc.o bfa_ioc_ct.o bfa_cee.o
+bna-objs += cna_fwimg.o
 
 EXTRA_CFLAGS := -Idrivers/net/bna

drivers/net/ethernet/brocade/bna/bfa_ioc.c

@@ -1968,18 +1968,22 @@ bfa_nw_ioc_mbox_regisr(struct bfa_ioc *ioc, enum bfi_mclass mc,
  * @param[in]	ioc	IOC instance
  * @param[i]	cmd	Mailbox command
  */
-void
-bfa_nw_ioc_mbox_queue(struct bfa_ioc *ioc, struct bfa_mbox_cmd *cmd)
+bool
+bfa_nw_ioc_mbox_queue(struct bfa_ioc *ioc, struct bfa_mbox_cmd *cmd,
+			bfa_mbox_cmd_cbfn_t cbfn, void *cbarg)
 {
 	struct bfa_ioc_mbox_mod *mod = &ioc->mbox_mod;
 	u32			stat;
 
+	cmd->cbfn = cbfn;
+	cmd->cbarg = cbarg;
+
 	/**
 	 * If a previous command is pending, queue new command
 	 */
 	if (!list_empty(&mod->cmd_q)) {
 		list_add_tail(&cmd->qe, &mod->cmd_q);
-		return;
+		return true;
 	}
 
 	/**
@@ -1988,15 +1992,15 @@ bfa_nw_ioc_mbox_queue(struct bfa_ioc *ioc, struct bfa_mbox_cmd *cmd)
 	stat = readl(ioc->ioc_regs.hfn_mbox_cmd);
 	if (stat) {
 		list_add_tail(&cmd->qe, &mod->cmd_q);
-		return;
+		return true;
 	}
 
 	/**
 	 * mailbox is free -- queue command to firmware
 	 */
 	bfa_ioc_mbox_send(ioc, cmd->msg, sizeof(cmd->msg));
 
-	return;
+	return false;
 }
 
 /**

drivers/net/ethernet/brocade/bna/bfa_ioc.h

@@ -253,7 +253,9 @@ struct bfa_ioc_hwif {
 /**
  * IOC mailbox interface
  */
-void bfa_nw_ioc_mbox_queue(struct bfa_ioc *ioc, struct bfa_mbox_cmd *cmd);
+bool bfa_nw_ioc_mbox_queue(struct bfa_ioc *ioc,
+			struct bfa_mbox_cmd *cmd,
+			bfa_mbox_cmd_cbfn_t cbfn, void *cbarg);
 void bfa_nw_ioc_mbox_isr(struct bfa_ioc *ioc);
 void bfa_nw_ioc_mbox_regisr(struct bfa_ioc *ioc, enum bfi_mclass mc,
 		bfa_ioc_mbox_mcfunc_t cbfn, void *cbarg);