#include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/kernel.h>
-#include <linux/mutex.h>
 #include <linux/slab.h>
+#include <linux/spinlock.h>
 #include <linux/string.h>
 #include "qed.h"
 #include "qed_hsi.h"
        if (!p_info->mfw_mb_shadow || !p_info->mfw_mb_addr)
                goto err;
 
-       /* Initialize the MFW mutex */
-       mutex_init(&p_info->mutex);
+       /* Initialize the MFW spinlock */
+       spin_lock_init(&p_info->lock);
 
        return 0;
 
        return -ENOMEM;
 }
 
+/* Locks the MFW mailbox of a PF to ensure a single access.
+ * The lock is achieved in most cases by holding a spinlock, causing other
+ * threads to wait till a previous access is done.
+ * In some cases (currently when a [UN]LOAD_REQ commands are sent), the single
+ * access is achieved by setting a blocking flag, which will fail other
+ * competing contexts to send their mailboxes.
+ */
+static int qed_mcp_mb_lock(struct qed_hwfn *p_hwfn,
+                          u32 cmd)
+{
+       spin_lock_bh(&p_hwfn->mcp_info->lock);
+
+       /* The spinlock shouldn't be acquired when the mailbox command is
+        * [UN]LOAD_REQ, since the engine is locked by the MFW, and a parallel
+        * pending [UN]LOAD_REQ command of another PF together with a spinlock
+        * (i.e. interrupts are disabled) - can lead to a deadlock.
+        * It is assumed that for a single PF, no other mailbox commands can be
+        * sent from another context while sending LOAD_REQ, and that any
+        * parallel commands to UNLOAD_REQ can be cancelled.
+        */
+       if (cmd == DRV_MSG_CODE_LOAD_DONE || cmd == DRV_MSG_CODE_UNLOAD_DONE)
+               p_hwfn->mcp_info->block_mb_sending = false;
+
+       if (p_hwfn->mcp_info->block_mb_sending) {
+               DP_NOTICE(p_hwfn,
+                         "Trying to send a MFW mailbox command [0x%x] in parallel to [UN]LOAD_REQ. Aborting.\n",
+                         cmd);
+               spin_unlock_bh(&p_hwfn->mcp_info->lock);
+               return -EBUSY;
+       }
+
+       if (cmd == DRV_MSG_CODE_LOAD_REQ || cmd == DRV_MSG_CODE_UNLOAD_REQ) {
+               p_hwfn->mcp_info->block_mb_sending = true;
+               spin_unlock_bh(&p_hwfn->mcp_info->lock);
+       }
+
+       return 0;
+}
+
+static void qed_mcp_mb_unlock(struct qed_hwfn  *p_hwfn,
+                             u32               cmd)
+{
+       if (cmd != DRV_MSG_CODE_LOAD_REQ && cmd != DRV_MSG_CODE_UNLOAD_REQ)
+               spin_unlock_bh(&p_hwfn->mcp_info->lock);
+}
+
 int qed_mcp_reset(struct qed_hwfn *p_hwfn,
                  struct qed_ptt *p_ptt)
 {
        u32 org_mcp_reset_seq, cnt = 0;
        int rc = 0;
 
+       /* Ensure that only a single thread is accessing the mailbox at a
+        * certain time.
+        */
+       rc = qed_mcp_mb_lock(p_hwfn, DRV_MSG_CODE_MCP_RESET);
+       if (rc != 0)
+               return rc;
+
        /* Set drv command along with the updated sequence */
        org_mcp_reset_seq = qed_rd(p_hwfn, p_ptt, MISCS_REG_GENERIC_POR_0);
        DRV_MB_WR(p_hwfn, p_ptt, drv_mb_header,
                rc = -EAGAIN;
        }
 
+       qed_mcp_mb_unlock(p_hwfn, DRV_MSG_CODE_MCP_RESET);
+
        return rc;
 }
 
        return rc;
 }
 
-int qed_mcp_cmd(struct qed_hwfn *p_hwfn,
-               struct qed_ptt *p_ptt,
-               u32 cmd,
-               u32 param,
-               u32 *o_mcp_resp,
-               u32 *o_mcp_param)
+static int qed_mcp_cmd_and_union(struct qed_hwfn *p_hwfn,
+                                struct qed_ptt *p_ptt,
+                                struct qed_mcp_mb_params *p_mb_params)
 {
-       int rc = 0;
+       u32 union_data_addr;
+       int rc;
 
        /* MCP not initialized */
        if (!qed_mcp_is_init(p_hwfn)) {
                return -EBUSY;
        }
 
-       /* Lock Mutex to ensure only single thread is
-        * accessing the MCP at one time
+       union_data_addr = p_hwfn->mcp_info->drv_mb_addr +
+                         offsetof(struct public_drv_mb, union_data);
+
+       /* Ensure that only a single thread is accessing the mailbox at a
+        * certain time.
         */
-       mutex_lock(&p_hwfn->mcp_info->mutex);
-       rc = qed_do_mcp_cmd(p_hwfn, p_ptt, cmd, param,
-                           o_mcp_resp, o_mcp_param);
-       /* Release Mutex */
-       mutex_unlock(&p_hwfn->mcp_info->mutex);
+       rc = qed_mcp_mb_lock(p_hwfn, p_mb_params->cmd);
+       if (rc)
+               return rc;
+
+       if (p_mb_params->p_data_src != NULL)
+               qed_memcpy_to(p_hwfn, p_ptt, union_data_addr,
+                             p_mb_params->p_data_src,
+                             sizeof(*p_mb_params->p_data_src));
+
+       rc = qed_do_mcp_cmd(p_hwfn, p_ptt, p_mb_params->cmd,
+                           p_mb_params->param, &p_mb_params->mcp_resp,
+                           &p_mb_params->mcp_param);
+
+       if (p_mb_params->p_data_dst != NULL)
+               qed_memcpy_from(p_hwfn, p_ptt, p_mb_params->p_data_dst,
+                               union_data_addr,
+                               sizeof(*p_mb_params->p_data_dst));
+
+       qed_mcp_mb_unlock(p_hwfn, p_mb_params->cmd);
 
        return rc;
 }
 
-static void qed_mcp_set_drv_ver(struct qed_dev *cdev,
-                               struct qed_hwfn *p_hwfn,
-                               struct qed_ptt *p_ptt)
+int qed_mcp_cmd(struct qed_hwfn *p_hwfn,
+               struct qed_ptt *p_ptt,
+               u32 cmd,
+               u32 param,
+               u32 *o_mcp_resp,
+               u32 *o_mcp_param)
 {
-       u32 i;
+       struct qed_mcp_mb_params mb_params;
+       int rc;
+
+       memset(&mb_params, 0, sizeof(mb_params));
+       mb_params.cmd = cmd;
+       mb_params.param = param;
+       rc = qed_mcp_cmd_and_union(p_hwfn, p_ptt, &mb_params);
+       if (rc)
+               return rc;
+
+       *o_mcp_resp = mb_params.mcp_resp;
+       *o_mcp_param = mb_params.mcp_param;
 
-       /* Copy version string to MCP */
-       for (i = 0; i < MCP_DRV_VER_STR_SIZE_DWORD; i++)
-               DRV_MB_WR(p_hwfn, p_ptt, union_data.ver_str[i],
-                         *(u32 *)&cdev->ver_str[i * sizeof(u32)]);
+       return 0;
 }
 
 int qed_mcp_load_req(struct qed_hwfn *p_hwfn,
                     u32 *p_load_code)
 {
        struct qed_dev *cdev = p_hwfn->cdev;
-       u32 param;
+       struct qed_mcp_mb_params mb_params;
+       union drv_union_data union_data;
        int rc;
 
-       if (!qed_mcp_is_init(p_hwfn)) {
-               DP_NOTICE(p_hwfn, "MFW is not initialized !\n");
-               return -EBUSY;
-       }
-
-       /* Save driver's version to shmem */
-       qed_mcp_set_drv_ver(cdev, p_hwfn, p_ptt);
-
-       DP_VERBOSE(p_hwfn, QED_MSG_SP, "fw_seq 0x%08x, drv_pulse 0x%x\n",
-                  p_hwfn->mcp_info->drv_mb_seq,
-                  p_hwfn->mcp_info->drv_pulse_seq);
-
+       memset(&mb_params, 0, sizeof(mb_params));
        /* Load Request */
-       rc = qed_mcp_cmd(p_hwfn, p_ptt, DRV_MSG_CODE_LOAD_REQ,
-                        (PDA_COMP | DRV_ID_MCP_HSI_VER_CURRENT |
-                         cdev->drv_type),
-                        p_load_code, ¶m);
+       mb_params.cmd = DRV_MSG_CODE_LOAD_REQ;
+       mb_params.param = PDA_COMP | DRV_ID_MCP_HSI_VER_CURRENT |
+                         cdev->drv_type;
+       memcpy(&union_data.ver_str, cdev->ver_str, MCP_DRV_VER_STR_SIZE);
+       mb_params.p_data_src = &union_data;
+       rc = qed_mcp_cmd_and_union(p_hwfn, p_ptt, &mb_params);
 
        /* if mcp fails to respond we must abort */
        if (rc) {
                return rc;
        }
 
+       *p_load_code = mb_params.mcp_resp;
+
        /* If MFW refused (e.g. other port is in diagnostic mode) we
         * must abort. This can happen in the following cases:
         * - Other port is in diagnostic mode
                     bool b_up)
 {
        struct qed_mcp_link_params *params = &p_hwfn->mcp_info->link_input;
-       u32 param = 0, reply = 0, cmd;
-       struct pmm_phy_cfg phy_cfg;
+       struct qed_mcp_mb_params mb_params;
+       union drv_union_data union_data;
+       struct pmm_phy_cfg *phy_cfg;
        int rc = 0;
-       u32 i;
-
-       if (!qed_mcp_is_init(p_hwfn)) {
-               DP_NOTICE(p_hwfn, "MFW is not initialized !\n");
-               return -EBUSY;
-       }
+       u32 cmd;
 
        /* Set the shmem configuration according to params */
-       memset(&phy_cfg, 0, sizeof(phy_cfg));
+       phy_cfg = &union_data.drv_phy_cfg;
+       memset(phy_cfg, 0, sizeof(*phy_cfg));
        cmd = b_up ? DRV_MSG_CODE_INIT_PHY : DRV_MSG_CODE_LINK_RESET;
        if (!params->speed.autoneg)
-               phy_cfg.speed = params->speed.forced_speed;
-       phy_cfg.pause |= (params->pause.autoneg) ? PMM_PAUSE_AUTONEG : 0;
-       phy_cfg.pause |= (params->pause.forced_rx) ? PMM_PAUSE_RX : 0;
-       phy_cfg.pause |= (params->pause.forced_tx) ? PMM_PAUSE_TX : 0;
-       phy_cfg.adv_speed = params->speed.advertised_speeds;
-       phy_cfg.loopback_mode = params->loopback_mode;
-
-       /* Write the requested configuration to shmem */
-       for (i = 0; i < sizeof(phy_cfg); i += 4)
-               qed_wr(p_hwfn, p_ptt,
-                      p_hwfn->mcp_info->drv_mb_addr +
-                      offsetof(struct public_drv_mb, union_data) + i,
-                      ((u32 *)&phy_cfg)[i >> 2]);
+               phy_cfg->speed = params->speed.forced_speed;
+       phy_cfg->pause |= (params->pause.autoneg) ? PMM_PAUSE_AUTONEG : 0;
+       phy_cfg->pause |= (params->pause.forced_rx) ? PMM_PAUSE_RX : 0;
+       phy_cfg->pause |= (params->pause.forced_tx) ? PMM_PAUSE_TX : 0;
+       phy_cfg->adv_speed = params->speed.advertised_speeds;
+       phy_cfg->loopback_mode = params->loopback_mode;
 
        p_hwfn->b_drv_link_init = b_up;
 
        if (b_up) {
                DP_VERBOSE(p_hwfn, NETIF_MSG_LINK,
                           "Configuring Link: Speed 0x%08x, Pause 0x%08x, adv_speed 0x%08x, loopback 0x%08x, features 0x%08x\n",
-                          phy_cfg.speed,
-                          phy_cfg.pause,
-                          phy_cfg.adv_speed,
-                          phy_cfg.loopback_mode,
-                          phy_cfg.feature_config_flags);
+                          phy_cfg->speed,
+                          phy_cfg->pause,
+                          phy_cfg->adv_speed,
+                          phy_cfg->loopback_mode,
+                          phy_cfg->feature_config_flags);
        } else {
                DP_VERBOSE(p_hwfn, NETIF_MSG_LINK,
                           "Resetting link\n");
        }
 
-       DP_VERBOSE(p_hwfn, QED_MSG_SP, "fw_seq 0x%08x, drv_pulse 0x%x\n",
-                  p_hwfn->mcp_info->drv_mb_seq,
-                  p_hwfn->mcp_info->drv_pulse_seq);
-
-       /* Load Request */
-       rc = qed_mcp_cmd(p_hwfn, p_ptt, cmd, 0, &reply, ¶m);
+       memset(&mb_params, 0, sizeof(mb_params));
+       mb_params.cmd = cmd;
+       mb_params.p_data_src = &union_data;
+       rc = qed_mcp_cmd_and_union(p_hwfn, p_ptt, &mb_params);
 
        /* if mcp fails to respond we must abort */
        if (rc) {
                         struct qed_ptt *p_ptt,
                         struct qed_mcp_drv_version *p_ver)
 {
-       int rc = 0;
-       u32 param = 0, reply = 0, i;
-
-       if (!qed_mcp_is_init(p_hwfn)) {
-               DP_NOTICE(p_hwfn, "MFW is not initialized !\n");
-               return -EBUSY;
-       }
+       struct drv_version_stc *p_drv_version;
+       struct qed_mcp_mb_params mb_params;
+       union drv_union_data union_data;
+       __be32 val;
+       u32 i;
+       int rc;
 
-       DRV_MB_WR(p_hwfn, p_ptt, union_data.drv_version.version,
-                 p_ver->version);
-       /* Copy version string to shmem */
-       for (i = 0; i < (MCP_DRV_VER_STR_SIZE - 4) / 4; i++) {
-               DRV_MB_WR(p_hwfn, p_ptt,
-                         union_data.drv_version.name[i * sizeof(u32)],
-                         *(u32 *)&p_ver->name[i * sizeof(u32)]);
+       p_drv_version = &union_data.drv_version;
+       p_drv_version->version = p_ver->version;
+       for (i = 0; i < MCP_DRV_VER_STR_SIZE - 1; i += 4) {
+               val = cpu_to_be32(p_ver->name[i]);
+               *(u32 *)&p_drv_version->name[i * sizeof(u32)] = val;
        }
 
-       rc = qed_mcp_cmd(p_hwfn, p_ptt, DRV_MSG_CODE_SET_VERSION, 0, &reply,
-                        ¶m);
-       if (rc) {
+       memset(&mb_params, 0, sizeof(mb_params));
+       mb_params.cmd = DRV_MSG_CODE_SET_VERSION;
+       mb_params.p_data_src = &union_data;
+       rc = qed_mcp_cmd_and_union(p_hwfn, p_ptt, &mb_params);
+       if (rc)
                DP_ERR(p_hwfn, "MCP response failure, aborting\n");
-               return rc;
-       }
 
-       return 0;
+       return rc;
 }
 
 int qed_mcp_set_led(struct qed_hwfn *p_hwfn, struct qed_ptt *p_ptt,