From: Vadim Pasternak <vadimp@mellanox.com>
Date: Sun, 6 Oct 2019 09:34:52 +0300
Subject: mlxsw: minimal: Add validation for FW version
Patch-mainline: v5.5-rc1
Git-commit: 6935af8073a02ffd11a7e495dc318c0a51e18012
References: bsc#1154488

Add validation for FW version in order to prevent driver initialization
in case FW version is older than expected. FW version validation is
necessary, because use of a new field 'num_of_modules' in MGPIR register
is not backward compatible. FW 'minor' and 'subminor' versions are
expected to be greater than or equal to 2000 and 1886, respectively.

Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlxsw/minimal.c |   30 ++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

--- a/drivers/net/ethernet/mellanox/mlxsw/minimal.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/minimal.c
@@ -16,6 +16,14 @@
 
 static const char mlxsw_m_driver_name[] = "mlxsw_minimal";
 
+#define MLXSW_M_FWREV_MINOR	2000
+#define MLXSW_M_FWREV_SUBMINOR	1886
+
+static const struct mlxsw_fw_rev mlxsw_m_fw_rev = {
+	.minor = MLXSW_M_FWREV_MINOR,
+	.subminor = MLXSW_M_FWREV_SUBMINOR,
+};
+
 struct mlxsw_m_port;
 
 struct mlxsw_m {
@@ -326,6 +334,24 @@ static void mlxsw_m_ports_remove(struct
 	kfree(mlxsw_m->ports);
 }
 
+static int mlxsw_m_fw_rev_validate(struct mlxsw_m *mlxsw_m)
+{
+	const struct mlxsw_fw_rev *rev = &mlxsw_m->bus_info->fw_rev;
+
+	/* Validate driver and FW are compatible.
+	 * Do not check major version, since it defines chip type, while
+	 * driver is supposed to support any type.
+	 */
+	if (mlxsw_core_fw_rev_minor_subminor_validate(rev, &mlxsw_m_fw_rev))
+		return 0;
+
+	dev_err(mlxsw_m->bus_info->dev, "The firmware version %d.%d.%d is incompatible with the driver (required >= %d.%d.%d)\n",
+		rev->major, rev->minor, rev->subminor, rev->major,
+		mlxsw_m_fw_rev.minor, mlxsw_m_fw_rev.subminor);
+
+	return -EINVAL;
+}
+
 static int mlxsw_m_init(struct mlxsw_core *mlxsw_core,
 			const struct mlxsw_bus_info *mlxsw_bus_info,
 			struct netlink_ext_ack *extack)
@@ -336,6 +362,10 @@ static int mlxsw_m_init(struct mlxsw_cor
 	mlxsw_m->core = mlxsw_core;
 	mlxsw_m->bus_info = mlxsw_bus_info;
 
+	err = mlxsw_m_fw_rev_validate(mlxsw_m);
+	if (err)
+		return err;
+
 	err = mlxsw_m_base_mac_get(mlxsw_m);
 	if (err) {
 		dev_err(mlxsw_m->bus_info->dev, "Failed to get base mac\n");