diff --git a/drivers/net/ethernet/mellanox/mlx4/cmd.c b/drivers/net/ethernet/mellanox/mlx4/cmd.c
index b27654e..9c0bdca 100644
--- a/drivers/net/ethernet/mellanox/mlx4/cmd.c
+++ b/drivers/net/ethernet/mellanox/mlx4/cmd.c
@@ -39,12 +39,18 @@
 #include <linux/errno.h>
 
 #include <linux/mlx4/cmd.h>
+#include <linux/semaphore.h>
 
 #include <asm/io.h>
 
 #include "mlx4.h"
+#include "fw.h"
 
 #define CMD_POLL_TOKEN 0xffff
+#define INBOX_MASK	0xffffffffffffff00ULL
+
+#define CMD_CHAN_VER 1
+#define CMD_CHAN_IF_REV 1
 
 enum {
 	/* command completed successfully: */
@@ -110,8 +116,12 @@ struct mlx4_cmd_context {
 	int			next;
 	u64			out_param;
 	u16			token;
+	u8			fw_status;
 };
 
+static int mlx4_master_process_vhcr(struct mlx4_dev *dev, int slave,
+				    struct mlx4_vhcr_cmd *in_vhcr);
+
 static int mlx4_status_to_errno(u8 status)
 {
 	static const int trans_table[] = {
@@ -142,6 +152,125 @@ static int mlx4_status_to_errno(u8 status)
 	return trans_table[status];
 }
 
+static int comm_pending(struct mlx4_dev *dev)
+{
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	u32 status = readl(&priv->mfunc.comm->slave_read);
+
+	return (swab32(status) >> 31) != priv->cmd.comm_toggle;
+}
+
+static void mlx4_comm_cmd_post(struct mlx4_dev *dev, u8 cmd, u16 param)
+{
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	u32 val;
+
+	priv->cmd.comm_toggle ^= 1;
+	val = param | (cmd << 16) | (priv->cmd.comm_toggle << 31);
+	__raw_writel((__force u32) cpu_to_be32(val),
+		     &priv->mfunc.comm->slave_write);
+	mmiowb();
+}
+
+/* dummy procedure for this patch */
+int mlx4_GEN_EQE(struct mlx4_dev *dev, int slave, struct mlx4_eqe *eqe)
+{
+	return 0;
+}
+
+static int mlx4_comm_cmd_poll(struct mlx4_dev *dev, u8 cmd, u16 param,
+		       unsigned long timeout)
+{
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	unsigned long end;
+	int err = 0;
+	int ret_from_pending = 0;
+
+	/* First, verify that the master reports correct status */
+	if (comm_pending(dev)) {
+		mlx4_warn(dev, "Communication channel is not idle."
+			  "my toggle is %d (cmd:0x%x)\n",
+			  priv->cmd.comm_toggle, cmd);
+		return -EAGAIN;
+	}
+
+	/* Write command */
+	down(&priv->cmd.poll_sem);
+	mlx4_comm_cmd_post(dev, cmd, param);
+
+	end = msecs_to_jiffies(timeout) + jiffies;
+	while (comm_pending(dev) && time_before(jiffies, end))
+		cond_resched();
+	ret_from_pending = comm_pending(dev);
+	if (ret_from_pending) {
+		/* check if the slave is trying to boot in the middle of
+		 * FLR process. The only non-zero result in the RESET command
+		 * is MLX4_DELAY_RESET_SLAVE*/
+		if ((MLX4_COMM_CMD_RESET == cmd)) {
+			mlx4_warn(dev, "Got slave FLRed from Communication"
+				  " channel (ret:0x%x)\n", ret_from_pending);
+			err = MLX4_DELAY_RESET_SLAVE;
+		} else {
+			mlx4_warn(dev, "Communication channel timed out\n");
+			err = -ETIMEDOUT;
+		}
+	}
+
+	up(&priv->cmd.poll_sem);
+	return err;
+}
+
+static int mlx4_comm_cmd_wait(struct mlx4_dev *dev, u8 op,
+			      u16 param, unsigned long timeout)
+{
+	struct mlx4_cmd *cmd = &mlx4_priv(dev)->cmd;
+	struct mlx4_cmd_context *context;
+	int err = 0;
+
+	down(&cmd->event_sem);
+
+	spin_lock(&cmd->context_lock);
+	BUG_ON(cmd->free_head < 0);
+	context = &cmd->context[cmd->free_head];
+	context->token += cmd->token_mask + 1;
+	cmd->free_head = context->next;
+	spin_unlock(&cmd->context_lock);
+
+	init_completion(&context->done);
+
+	mlx4_comm_cmd_post(dev, op, param);
+
+	if (!wait_for_completion_timeout(&context->done,
+					 msecs_to_jiffies(timeout))) {
+		err = -EBUSY;
+		goto out;
+	}
+
+	err = context->result;
+	if (err && context->fw_status != CMD_STAT_MULTI_FUNC_REQ) {
+		mlx4_err(dev, "command 0x%x failed: fw status = 0x%x\n",
+			 op, context->fw_status);
+		goto out;
+	}
+
+out:
+	spin_lock(&cmd->context_lock);
+	context->next = cmd->free_head;
+	cmd->free_head = context - cmd->context;
+	spin_unlock(&cmd->context_lock);
+
+	up(&cmd->event_sem);
+	return err;
+}
+
+static int mlx4_comm_cmd(struct mlx4_dev *dev, u8 cmd, u16 param,
+		  unsigned long timeout)
+{
+	if (mlx4_priv(dev)->cmd.use_events)
+		return mlx4_comm_cmd_wait(dev, cmd, param, timeout);
+	return mlx4_comm_cmd_poll(dev, cmd, param, timeout);
+}
+
 static int cmd_pending(struct mlx4_dev *dev)
 {
 	u32 status = readl(mlx4_priv(dev)->cmd.hcr + HCR_STATUS_OFFSET);
@@ -167,8 +296,10 @@ static int mlx4_cmd_post(struct mlx4_dev *dev, u64 in_param, u64 out_param,
 		end += msecs_to_jiffies(GO_BIT_TIMEOUT_MSECS);
 
 	while (cmd_pending(dev)) {
-		if (time_after_eq(jiffies, end))
+		if (time_after_eq(jiffies, end)) {
+			mlx4_err(dev, "%s:cmd_pending failed\n", __func__);
 			goto out;
+		}
 		cond_resched();
 	}
 
@@ -192,7 +323,7 @@ static int mlx4_cmd_post(struct mlx4_dev *dev, u64 in_param, u64 out_param,
 					       (cmd->toggle << HCR_T_BIT)	|
 					       (event ? (1 << HCR_E_BIT) : 0)	|
 					       (op_modifier << HCR_OPMOD_SHIFT) |
-					       op),			  hcr + 6);
+					       op), hcr + 6);
 
 	/*
 	 * Make sure that our HCR writes don't get mixed in with
@@ -209,6 +340,62 @@ out:
 	return ret;
 }
 
+static int mlx4_slave_cmd(struct mlx4_dev *dev, u64 in_param, u64 *out_param,
+			  int out_is_imm, u32 in_modifier, u8 op_modifier,
+			  u16 op, unsigned long timeout)
+{
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	struct mlx4_vhcr_cmd *vhcr = priv->mfunc.vhcr;
+	int ret;
+
+	down(&priv->cmd.slave_sem);
+	vhcr->in_param = cpu_to_be64(in_param);
+	vhcr->out_param = out_param ? cpu_to_be64(*out_param) : 0;
+	vhcr->in_modifier = cpu_to_be32(in_modifier);
+	vhcr->opcode = cpu_to_be16((((u16) op_modifier) << 12) | (op & 0xfff));
+	vhcr->token = cpu_to_be16(CMD_POLL_TOKEN);
+	vhcr->status = 0;
+	vhcr->flags = !!(priv->cmd.use_events) << 6;
+	if (mlx4_is_master(dev)) {
+		ret = mlx4_master_process_vhcr(dev, dev->caps.function, vhcr);
+		if (!ret) {
+			if (out_is_imm) {
+				if (out_param)
+					*out_param =
+						be64_to_cpu(vhcr->out_param);
+				else {
+					mlx4_err(dev, "response expected while"
+						 "output mailbox is NULL for "
+						 "command 0x%x\n", op);
+					vhcr->status = -EINVAL;
+				}
+			}
+			ret = vhcr->status;
+		}
+	} else {
+		ret = mlx4_comm_cmd(dev, MLX4_COMM_CMD_VHCR_POST, 0,
+				    MLX4_COMM_TIME + timeout);
+		if (!ret) {
+			if (out_is_imm) {
+				if (out_param)
+					*out_param =
+						be64_to_cpu(vhcr->out_param);
+				else {
+					mlx4_err(dev, "response expected while"
+						 "output mailbox is NULL for "
+						 "command 0x%x\n", op);
+					vhcr->status = -EINVAL;
+				}
+			}
+			ret = vhcr->status;
+		} else
+			mlx4_err(dev, "failed execution of VHCR_POST command"
+				 "opcode 0x%x\n", op);
+	}
+	up(&priv->cmd.slave_sem);
+	return ret;
+}
+
 static int mlx4_cmd_poll(struct mlx4_dev *dev, u64 in_param, u64 *out_param,
 			 int out_is_imm, u32 in_modifier, u8 op_modifier,
 			 u16 op, unsigned long timeout)
@@ -217,6 +404,7 @@ static int mlx4_cmd_poll(struct mlx4_dev *dev, u64 in_param, u64 *out_param,
 	void __iomem *hcr = priv->cmd.hcr;
 	int err = 0;
 	unsigned long end;
+	u32 stat;
 
 	down(&priv->cmd.poll_sem);
 
@@ -240,9 +428,12 @@ static int mlx4_cmd_poll(struct mlx4_dev *dev, u64 in_param, u64 *out_param,
 					  __raw_readl(hcr + HCR_OUT_PARAM_OFFSET)) << 32 |
 			(u64) be32_to_cpu((__force __be32)
 					  __raw_readl(hcr + HCR_OUT_PARAM_OFFSET + 4));
-
-	err = mlx4_status_to_errno(be32_to_cpu((__force __be32)
-					       __raw_readl(hcr + HCR_STATUS_OFFSET)) >> 24);
+	stat = be32_to_cpu((__force __be32)
+			   __raw_readl(hcr + HCR_STATUS_OFFSET)) >> 24;
+	err = mlx4_status_to_errno(stat);
+	if (err)
+		mlx4_err(dev, "command 0x%x failed: fw status = 0x%x\n",
+			 op, stat);
 
 out:
 	up(&priv->cmd.poll_sem);
@@ -259,6 +450,7 @@ void mlx4_cmd_event(struct mlx4_dev *dev, u16 token, u8 status, u64 out_param)
 	if (token != context->token)
 		return;
 
+	context->fw_status = status;
 	context->result    = mlx4_status_to_errno(status);
 	context->out_param = out_param;
 
@@ -287,14 +479,18 @@ static int mlx4_cmd_wait(struct mlx4_dev *dev, u64 in_param, u64 *out_param,
 	mlx4_cmd_post(dev, in_param, out_param ? *out_param : 0,
 		      in_modifier, op_modifier, op, context->token, 1);
 
-	if (!wait_for_completion_timeout(&context->done, msecs_to_jiffies(timeout))) {
+	if (!wait_for_completion_timeout(&context->done,
+					 msecs_to_jiffies(timeout))) {
 		err = -EBUSY;
 		goto out;
 	}
 
 	err = context->result;
-	if (err)
+	if (err) {
+		mlx4_err(dev, "command 0x%x failed: fw status = 0x%x\n",
+			 op, context->fw_status);
 		goto out;
+	}
 
 	if (out_is_imm)
 		*out_param = context->out_param;
@@ -313,15 +509,448 @@ int __mlx4_cmd(struct mlx4_dev *dev, u64 in_param, u64 *out_param,
 	       int out_is_imm, u32 in_modifier, u8 op_modifier,
 	       u16 op, unsigned long timeout, int native)
 {
-	if (mlx4_priv(dev)->cmd.use_events)
-		return mlx4_cmd_wait(dev, in_param, out_param, out_is_imm,
-				     in_modifier, op_modifier, op, timeout);
-	else
-		return mlx4_cmd_poll(dev, in_param, out_param, out_is_imm,
-				     in_modifier, op_modifier, op, timeout);
+	if (!mlx4_is_mfunc(dev) || (native && mlx4_is_master(dev))) {
+		if (mlx4_priv(dev)->cmd.use_events)
+			return mlx4_cmd_wait(dev, in_param, out_param,
+					     out_is_imm, in_modifier,
+					     op_modifier, op, timeout);
+		else
+			return mlx4_cmd_poll(dev, in_param, out_param,
+					     out_is_imm, in_modifier,
+					     op_modifier, op, timeout);
+	}
+	return mlx4_slave_cmd(dev, in_param, out_param, out_is_imm,
+			      in_modifier, op_modifier, op, timeout);
 }
 EXPORT_SYMBOL_GPL(__mlx4_cmd);
 
+
+static int mlx4_ARM_COMM_CHANNEL(struct mlx4_dev *dev)
+{
+	return mlx4_cmd(dev, 0, 0, 0, MLX4_CMD_ARM_COMM_CHANNEL,
+			MLX4_CMD_TIME_CLASS_B, MLX4_CMD_NATIVE);
+}
+
+static int mlx4_ACCESS_MEM(struct mlx4_dev *dev, u64 master_addr,
+			   int slave, u64 slave_addr,
+			   int size, int is_read)
+{
+	u64 in_param;
+	u64 out_param;
+
+	if ((slave_addr & 0xfff) | (master_addr & 0xfff) |
+	    (slave & ~0x7f) | (size & 0xff)) {
+		mlx4_err(dev, "Bad access mem params - slave_addr:0x%llx "
+			      "master_addr:0x%llx slave_id:%d size:%d\n",
+			      slave_addr, master_addr, slave, size);
+		return -EINVAL;
+	}
+
+	if (is_read) {
+		in_param = (u64) slave | slave_addr;
+		out_param = (u64) dev->caps.function | master_addr;
+	} else {
+		in_param = (u64) dev->caps.function | master_addr;
+		out_param = (u64) slave | slave_addr;
+	}
+
+	return mlx4_cmd_imm(dev, in_param, &out_param, size, 0,
+			    MLX4_CMD_ACCESS_MEM,
+			    MLX4_CMD_TIME_CLASS_A, MLX4_CMD_NATIVE);
+}
+
+int mlx4_DMA_wrapper(struct mlx4_dev *dev, int slave,
+		     struct mlx4_vhcr *vhcr,
+		     struct mlx4_cmd_mailbox *inbox,
+		     struct mlx4_cmd_mailbox *outbox,
+		     struct mlx4_cmd_info *cmd)
+{
+	u64 in_param;
+	u64 out_param;
+	int err;
+
+	in_param = cmd->has_inbox ? (u64) inbox->dma : vhcr->in_param;
+	out_param = cmd->has_outbox ? (u64) outbox->dma : vhcr->out_param;
+	if (cmd->encode_slave_id) {
+		in_param &= 0xffffffffffffff00ll;
+		in_param |= slave;
+	}
+
+	err = __mlx4_cmd(dev, in_param, &out_param, cmd->out_is_imm,
+			 vhcr->in_modifier, vhcr->op_modifier, vhcr->op,
+			 MLX4_CMD_TIME_CLASS_A, MLX4_CMD_NATIVE);
+
+	if (cmd->out_is_imm)
+		vhcr->out_param = out_param;
+
+	return err;
+}
+
+static struct mlx4_cmd_info cmd_info[] = {
+	{
+		.opcode = MLX4_CMD_QUERY_FW,
+		.has_inbox = false,
+		.has_outbox = true,
+		.out_is_imm = false,
+		.encode_slave_id = false,
+		.verify = NULL,
+		.wrapper = NULL
+	},
+	{
+		.opcode = MLX4_CMD_QUERY_HCA,
+		.has_inbox = false,
+		.has_outbox = true,
+		.out_is_imm = false,
+		.encode_slave_id = false,
+		.verify = NULL,
+		.wrapper = NULL
+	},
+	{
+		.opcode = MLX4_CMD_QUERY_DEV_CAP,
+		.has_inbox = false,
+		.has_outbox = true,
+		.out_is_imm = false,
+		.encode_slave_id = false,
+		.verify = NULL,
+		.wrapper = NULL
+	},
+};
+
+static int mlx4_master_process_vhcr(struct mlx4_dev *dev, int slave,
+				    struct mlx4_vhcr_cmd *in_vhcr)
+{
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	struct mlx4_cmd_info *cmd = NULL;
+	struct mlx4_vhcr_cmd *vhcr_cmd = in_vhcr ? in_vhcr : priv->mfunc.vhcr;
+	struct mlx4_vhcr *vhcr;
+	struct mlx4_cmd_mailbox *inbox = NULL;
+	struct mlx4_cmd_mailbox *outbox = NULL;
+	u64 in_param;
+	u64 out_param;
+	int ret = 0;
+	int i;
+
+	/* Create sw representation of Virtual HCR */
+	vhcr = kzalloc(sizeof(struct mlx4_vhcr), GFP_KERNEL);
+	if (!vhcr)
+		return -ENOMEM;
+
+	/* DMA in the vHCR */
+	if (!in_vhcr) {
+		ret = mlx4_ACCESS_MEM(dev, priv->mfunc.vhcr_dma, slave,
+				      priv->mfunc.master.slave_state[slave].vhcr_dma,
+				      ALIGN(sizeof(struct mlx4_vhcr_cmd),
+					    MLX4_ACCESS_MEM_ALIGN), 1);
+		if (ret) {
+			mlx4_err(dev, "%s:Failed reading vhcr"
+				 "ret: 0x%x\n", __func__, ret);
+			kfree(vhcr);
+			return ret;
+		}
+	}
+
+	/* Fill SW VHCR fields */
+	vhcr->in_param = be64_to_cpu(vhcr_cmd->in_param);
+	vhcr->out_param = be64_to_cpu(vhcr_cmd->out_param);
+	vhcr->in_modifier = be32_to_cpu(vhcr_cmd->in_modifier);
+	vhcr->token = be16_to_cpu(vhcr_cmd->token);
+	vhcr->op = be16_to_cpu(vhcr_cmd->opcode) & 0xfff;
+	vhcr->op_modifier = (u8) (be16_to_cpu(vhcr_cmd->opcode) >> 12);
+	vhcr->e_bit = vhcr_cmd->flags & (1 << 6);
+
+	/* Lookup command */
+	for (i = 0; i < ARRAY_SIZE(cmd_info); ++i) {
+		if (vhcr->op == cmd_info[i].opcode) {
+			cmd = &cmd_info[i];
+			break;
+		}
+	}
+	if (!cmd) {
+		mlx4_err(dev, "Unknown command:0x%x accepted from slave:%d\n",
+			 vhcr->op, slave);
+		vhcr_cmd->status = -EINVAL;
+		goto out_status;
+	}
+
+	/* Read inbox */
+	if (cmd->has_inbox) {
+		vhcr->in_param &= INBOX_MASK;
+		inbox = mlx4_alloc_cmd_mailbox(dev);
+		if (IS_ERR(inbox)) {
+			ret = PTR_ERR(inbox);
+			inbox = NULL;
+			goto out;
+		}
+
+		ret = mlx4_ACCESS_MEM(dev, inbox->dma, slave,
+				      vhcr->in_param,
+				      MLX4_MAILBOX_SIZE, 1);
+		if (ret) {
+			mlx4_err(dev, "%s: Failed reading inbox (cmd:0x%x)\n",
+				 __func__, cmd->opcode);
+			goto out;
+		}
+	}
+
+	/* Apply permission and bound checks if applicable */
+	if (cmd->verify && cmd->verify(dev, slave, vhcr, inbox)) {
+		mlx4_warn(dev, "Command:0x%x from slave: %d failed protection "
+			  "checks for resource_id:%d\n", vhcr->op, slave,
+			  vhcr->in_modifier);
+		vhcr_cmd->status = -EPERM;
+		goto out_status;
+	}
+
+	/* Allocate outbox */
+	if (cmd->has_outbox) {
+		outbox = mlx4_alloc_cmd_mailbox(dev);
+		if (IS_ERR(outbox)) {
+			ret = PTR_ERR(outbox);
+			outbox = NULL;
+			goto out;
+		}
+	}
+
+	/* Execute the command! */
+	if (cmd->wrapper) {
+		vhcr_cmd->status = cmd->wrapper(dev, slave, vhcr, inbox, outbox,
+					   cmd);
+		if (cmd->out_is_imm)
+			vhcr_cmd->out_param = cpu_to_be64(vhcr->out_param);
+	} else {
+		in_param = cmd->has_inbox ? (u64) inbox->dma :
+			vhcr->in_param;
+		out_param = cmd->has_outbox ? (u64) outbox->dma :
+			vhcr->out_param;
+		vhcr_cmd->status = __mlx4_cmd(dev, in_param, &out_param,
+					 cmd->out_is_imm, vhcr->in_modifier,
+					 vhcr->op_modifier, vhcr->op,
+					 MLX4_CMD_TIME_CLASS_A,
+					 MLX4_CMD_NATIVE);
+
+		if (vhcr_cmd->status) {
+			mlx4_warn(dev, "vhcr command:0x%x slave:%d failed with"
+				  " error:%d, status %d\n",
+				  vhcr->op, slave, vhcr->errno,
+				  vhcr_cmd->status);
+			ret = vhcr_cmd->status;
+			goto out;
+		}
+
+		if (cmd->out_is_imm) {
+			vhcr->out_param = out_param;
+			vhcr_cmd->out_param = cpu_to_be64(vhcr->out_param);
+		}
+	}
+
+	/* Write outbox if command completed successfully */
+	if (cmd->has_outbox && !vhcr->errno) {
+		ret = mlx4_ACCESS_MEM(dev, outbox->dma, slave,
+				      vhcr->out_param,
+				      MLX4_MAILBOX_SIZE, MLX4_CMD_WRAPPED);
+		if (ret) {
+			mlx4_err(dev, "%s:Failed writing outbox\n", __func__);
+			goto out;
+		}
+	}
+
+out_status:
+	/* DMA back vhcr result */
+	if (!in_vhcr) {
+		ret = mlx4_ACCESS_MEM(dev, priv->mfunc.vhcr_dma, slave,
+				      priv->mfunc.master.slave_state[slave].vhcr_dma,
+				      ALIGN(sizeof(struct mlx4_vhcr),
+					    MLX4_ACCESS_MEM_ALIGN),
+				      MLX4_CMD_WRAPPED);
+		if (ret)
+			mlx4_err(dev, "%s:Failed writing vhcr result\n",
+				 __func__);
+		else if (vhcr->e_bit &&
+			 mlx4_GEN_EQE(dev, slave, &priv->mfunc.master.cmd_eqe))
+				mlx4_warn(dev, "Failed to generate command completion "
+					  "eqe for slave %d\n", slave);
+	}
+
+out:
+	kfree(vhcr);
+	mlx4_free_cmd_mailbox(dev, inbox);
+	mlx4_free_cmd_mailbox(dev, outbox);
+	return ret;
+}
+
+static void mlx4_master_do_cmd(struct mlx4_dev *dev, int slave, u8 cmd,
+			       u16 param, u8 toggle)
+{
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	struct mlx4_slave_state *slave_state = priv->mfunc.master.slave_state;
+	u32 reply;
+	u32 slave_status = 0;
+	u8 is_going_down = 0;
+
+	slave_state[slave].comm_toggle ^= 1;
+	reply = (u32) slave_state[slave].comm_toggle << 31;
+	if (toggle != slave_state[slave].comm_toggle) {
+		mlx4_warn(dev, "Incorrect toggle %d from slave %d. *** MASTER"
+			  "STATE COMPROMISIED ***\n", toggle, slave);
+		goto reset_slave;
+	}
+	if (cmd == MLX4_COMM_CMD_RESET) {
+		mlx4_warn(dev, "Received reset from slave:%d\n", slave);
+		slave_state[slave].active = false;
+		/*check if we are in the middle of FLR process,
+		if so return "retry" status to the slave*/
+		if (MLX4_COMM_CMD_FLR == slave_state[slave].last_cmd) {
+			slave_status = MLX4_DELAY_RESET_SLAVE;
+			goto inform_slave_state;
+		}
+
+		/* write the version in the event field */
+		reply |= mlx4_comm_get_version();
+
+		goto reset_slave;
+	}
+	/*command from slave in the middle of FLR*/
+	if (cmd != MLX4_COMM_CMD_RESET &&
+	    MLX4_COMM_CMD_FLR == slave_state[slave].last_cmd) {
+		mlx4_warn(dev, "slave:%d is Trying to run cmd(0x%x) "
+			  "in the middle of FLR\n", slave, cmd);
+		return;
+	}
+
+	switch (cmd) {
+	case MLX4_COMM_CMD_VHCR0:
+		if (slave_state[slave].last_cmd != MLX4_COMM_CMD_RESET)
+			goto reset_slave;
+		slave_state[slave].vhcr_dma = ((u64) param) << 48;
+		priv->mfunc.master.slave_state[slave].cookie = 0;
+		mutex_init(&priv->mfunc.master.gen_eqe_mutex[slave]);
+		break;
+	case MLX4_COMM_CMD_VHCR1:
+		if (slave_state[slave].last_cmd != MLX4_COMM_CMD_VHCR0)
+			goto reset_slave;
+		slave_state[slave].vhcr_dma |= ((u64) param) << 32;
+		break;
+	case MLX4_COMM_CMD_VHCR2:
+		if (slave_state[slave].last_cmd != MLX4_COMM_CMD_VHCR1)
+			goto reset_slave;
+		slave_state[slave].vhcr_dma |= ((u64) param) << 16;
+		break;
+	case MLX4_COMM_CMD_VHCR_EN:
+		if (slave_state[slave].last_cmd != MLX4_COMM_CMD_VHCR2)
+			goto reset_slave;
+		slave_state[slave].vhcr_dma |= param;
+		slave_state[slave].active = true;
+		break;
+	case MLX4_COMM_CMD_VHCR_POST:
+		if ((slave_state[slave].last_cmd != MLX4_COMM_CMD_VHCR_EN) &&
+		    (slave_state[slave].last_cmd != MLX4_COMM_CMD_VHCR_POST))
+			goto reset_slave;
+		down(&priv->cmd.slave_sem);
+		if (mlx4_master_process_vhcr(dev, slave, NULL)) {
+			mlx4_err(dev, "Failed processing vhcr for slave:%d,"
+				 " reseting slave.\n", slave);
+			up(&priv->cmd.slave_sem);
+			goto reset_slave;
+		}
+		up(&priv->cmd.slave_sem);
+		break;
+	default:
+		mlx4_warn(dev, "Bad comm cmd:%d from slave:%d\n", cmd, slave);
+		goto reset_slave;
+	}
+	spin_lock(&priv->mfunc.master.slave_state_lock);
+	if (!slave_state[slave].is_slave_going_down)
+		slave_state[slave].last_cmd = cmd;
+	else
+		is_going_down = 1;
+	spin_unlock(&priv->mfunc.master.slave_state_lock);
+	if (is_going_down) {
+		mlx4_warn(dev, "Slave is going down aborting command(%d)"
+			  " executing from slave:%d\n",
+			  cmd, slave);
+		return;
+	}
+	__raw_writel((__force u32) cpu_to_be32(reply),
+		     &priv->mfunc.comm[slave].slave_read);
+	mmiowb();
+
+	return;
+
+reset_slave:
+	spin_lock(&priv->mfunc.master.slave_state_lock);
+	if (!slave_state[slave].is_slave_going_down)
+		slave_state[slave].last_cmd = MLX4_COMM_CMD_RESET;
+	spin_unlock(&priv->mfunc.master.slave_state_lock);
+	/*with slave in the middle of flr, no need to clean resources again.*/
+inform_slave_state:
+	memset(&slave_state[slave].event_eq, 0,
+	       sizeof(struct mlx4_slave_event_eq_info));
+	__raw_writel((__force u32) cpu_to_be32(reply),
+		     &priv->mfunc.comm[slave].slave_read);
+	wmb();
+}
+
+/* master command processing */
+void mlx4_master_comm_channel(struct work_struct *work)
+{
+	struct mlx4_mfunc_master_ctx *master =
+		container_of(work,
+			     struct mlx4_mfunc_master_ctx,
+			     comm_work);
+	struct mlx4_mfunc *mfunc =
+		container_of(master, struct mlx4_mfunc, master);
+	struct mlx4_priv *priv =
+		container_of(mfunc, struct mlx4_priv, mfunc);
+	struct mlx4_dev *dev = &priv->dev;
+	__be32 *bit_vec;
+	u32 comm_cmd;
+	u32 vec;
+	int i, j, slave;
+	int toggle;
+	int served = 0;
+	int reported = 0;
+	u32 slt;
+
+	bit_vec = master->comm_arm_bit_vector;
+	for (i = 0; i < COMM_CHANNEL_BIT_ARRAY_SIZE; i++) {
+		vec = be32_to_cpu(bit_vec[i]);
+		for (j = 0; j < 32; j++) {
+			if (!(vec & (1 << j)))
+				continue;
+			++reported;
+			slave = (i * 32) + j;
+			comm_cmd = swab32(readl(
+					  &mfunc->comm[slave].slave_write));
+			slt = swab32(readl(&mfunc->comm[slave].slave_read))
+				     >> 31;
+			toggle = comm_cmd >> 31;
+			if (toggle != slt) {
+				if (master->slave_state[slave].comm_toggle
+				    != slt) {
+					printk(KERN_INFO "slave %d out of sync."
+					       " read toggle %d, state toggle %d. "
+					       "Resynching.\n", slave, slt,
+					       master->slave_state[slave].comm_toggle);
+					master->slave_state[slave].comm_toggle =
+						slt;
+				}
+				mlx4_master_do_cmd(dev, slave,
+						   comm_cmd >> 16 & 0xff,
+						   comm_cmd & 0xffff, toggle);
+				++served;
+			}
+		}
+	}
+
+	if (reported && reported != served)
+		mlx4_warn(dev, "Got command event with bitmask from %d slaves"
+			  " but %d were served\n",
+			  reported, served);
+
+	if (mlx4_ARM_COMM_CHANNEL(dev))
+		mlx4_warn(dev, "Failed to arm comm channel events\n");
+}
+
 int mlx4_cmd_init(struct mlx4_dev *dev)
 {
 	struct mlx4_priv *priv = mlx4_priv(dev);
@@ -331,22 +960,30 @@ int mlx4_cmd_init(struct mlx4_dev *dev)
 	priv->cmd.use_events = 0;
 	priv->cmd.toggle     = 1;
 
-	priv->cmd.hcr = ioremap(pci_resource_start(dev->pdev, 0) + MLX4_HCR_BASE,
-				MLX4_HCR_SIZE);
-	if (!priv->cmd.hcr) {
-		mlx4_err(dev, "Couldn't map command register.");
-		return -ENOMEM;
+	priv->cmd.hcr = NULL;
+	priv->mfunc.vhcr = NULL;
+
+	if (!mlx4_is_slave(dev)) {
+		priv->cmd.hcr = ioremap(pci_resource_start(dev->pdev, 0) +
+					MLX4_HCR_BASE, MLX4_HCR_SIZE);
+		if (!priv->cmd.hcr) {
+			mlx4_err(dev, "Couldn't map command register.\n");
+			return -ENOMEM;
+		}
 	}
 
 	priv->cmd.pool = pci_pool_create("mlx4_cmd", dev->pdev,
 					 MLX4_MAILBOX_SIZE,
 					 MLX4_MAILBOX_SIZE, 0);
-	if (!priv->cmd.pool) {
-		iounmap(priv->cmd.hcr);
-		return -ENOMEM;
-	}
+	if (!priv->cmd.pool)
+		goto err_hcr;
 
 	return 0;
+
+err_hcr:
+	if (!mlx4_is_slave(dev))
+		iounmap(priv->cmd.hcr);
+	return -ENOMEM;
 }
 
 void mlx4_cmd_cleanup(struct mlx4_dev *dev)
@@ -354,7 +991,9 @@ void mlx4_cmd_cleanup(struct mlx4_dev *dev)
 	struct mlx4_priv *priv = mlx4_priv(dev);
 
 	pci_pool_destroy(priv->cmd.pool);
-	iounmap(priv->cmd.hcr);
+
+	if (!mlx4_is_slave(dev))
+		iounmap(priv->cmd.hcr);
 }
 
 /*
@@ -365,6 +1004,7 @@ int mlx4_cmd_use_events(struct mlx4_dev *dev)
 {
 	struct mlx4_priv *priv = mlx4_priv(dev);
 	int i;
+	int err = 0;
 
 	priv->cmd.context = kmalloc(priv->cmd.max_cmds *
 				   sizeof (struct mlx4_cmd_context),
@@ -389,11 +1029,10 @@ int mlx4_cmd_use_events(struct mlx4_dev *dev)
 		; /* nothing */
 	--priv->cmd.token_mask;
 
-	priv->cmd.use_events = 1;
-
 	down(&priv->cmd.poll_sem);
+	priv->cmd.use_events = 1;
 
-	return 0;
+	return err;
 }
 
 /*
@@ -433,7 +1072,8 @@ struct mlx4_cmd_mailbox *mlx4_alloc_cmd_mailbox(struct mlx4_dev *dev)
 }
 EXPORT_SYMBOL_GPL(mlx4_alloc_cmd_mailbox);
 
-void mlx4_free_cmd_mailbox(struct mlx4_dev *dev, struct mlx4_cmd_mailbox *mailbox)
+void mlx4_free_cmd_mailbox(struct mlx4_dev *dev,
+			   struct mlx4_cmd_mailbox *mailbox)
 {
 	if (!mailbox)
 		return;
@@ -442,3 +1082,8 @@ void mlx4_free_cmd_mailbox(struct mlx4_dev *dev, struct mlx4_cmd_mailbox *mailbo
 	kfree(mailbox);
 }
 EXPORT_SYMBOL_GPL(mlx4_free_cmd_mailbox);
+
+u32 mlx4_comm_get_version(void)
+{
+	 return ((u32) CMD_CHAN_IF_REV << 8) | (u32) CMD_CHAN_VER;
+}
