mlx4_core: Check firmware command interface revision

HCA firmware with incompatible changes to the FW commmand interface is
coming soon.  Add a check of the interface revision during
initialization and bail out if the firmware advertises a revision that
the driver doesn't know about.  This will avoid strange failures later
if the driver goes on using the wrong interface revision. 

Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 23 insertions, 2 deletions

diff --git a/drivers/net/mlx4/fw.c b/drivers/net/mlx4/fw.c
index ab259b2e11a5..e7ca118c8dfd 100644
--- a/drivers/net/mlx4/fw.c
+++ b/drivers/net/mlx4/fw.c
@@ -37,6 +37,10 @@
 #include "fw.h"
 #include "icm.h"
 
+enum {
+        MLX4_COMMAND_INTERFACE_REV      = 1
+};
+
 extern void __buggy_use_of_MLX4_GET(void);
 extern void __buggy_use_of_MLX4_PUT(void);
 
@@ -452,10 +456,12 @@ int mlx4_QUERY_FW(struct mlx4_dev *dev)
         u32 *outbox;
         int err = 0;
         u64 fw_ver;
+        u16 cmd_if_rev;
         u8 lg;
 
 #define QUERY_FW_OUT_SIZE             0x100
 #define QUERY_FW_VER_OFFSET            0x00
+#define QUERY_FW_CMD_IF_REV_OFFSET     0x0a
 #define QUERY_FW_MAX_CMD_OFFSET        0x0f
 #define QUERY_FW_ERR_START_OFFSET      0x30
 #define QUERY_FW_ERR_SIZE_OFFSET       0x38
@@ -484,14 +490,29 @@ int mlx4_QUERY_FW(struct mlx4_dev *dev)
                 ((fw_ver & 0xffff0000ull) >> 16) |
                 ((fw_ver & 0x0000ffffull) << 16);
 
+        MLX4_GET(cmd_if_rev, outbox, QUERY_FW_CMD_IF_REV_OFFSET);
+        if (cmd_if_rev != MLX4_COMMAND_INTERFACE_REV) {
+                mlx4_err(dev, "Installed FW has unsupported "
+                         "command interface revision %d.\n",
+                         cmd_if_rev);
+                mlx4_err(dev, "(Installed FW version is %d.%d.%03d)\n",
+                         (int) (dev->caps.fw_ver >> 32),
+                         (int) (dev->caps.fw_ver >> 16) & 0xffff,
+                         (int) dev->caps.fw_ver & 0xffff);
+                mlx4_err(dev, "This driver version supports only revision %d.\n",
+                         MLX4_COMMAND_INTERFACE_REV);
+                err = -ENODEV;
+                goto out;
+        }
+
         MLX4_GET(lg, outbox, QUERY_FW_MAX_CMD_OFFSET);
         cmd->max_cmds = 1 << lg;
 
-        mlx4_dbg(dev, "FW version %d.%d.%03d, max commands %d\n",
+        mlx4_dbg(dev, "FW version %d.%d.%03d (cmd intf rev %d), max commands %d\n",
                  (int) (dev->caps.fw_ver >> 32),
                  (int) (dev->caps.fw_ver >> 16) & 0xffff,
                  (int) dev->caps.fw_ver & 0xffff,
-                 cmd->max_cmds);
+                 cmd_if_rev, cmd->max_cmds);
 
         MLX4_GET(fw->catas_offset, outbox, QUERY_FW_ERR_START_OFFSET);
         MLX4_GET(fw->catas_size,   outbox, QUERY_FW_ERR_SIZE_OFFSET);