sfc_ef100: check firmware version at start-of-day

Early in EF100 development there was a different format of event
 descriptor; if the NIC is somehow running the very old firmware
 which will use that format, fail the probe.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/sfc/ef100_nic.c b/drivers/net/ethernet/sfc/ef100_nic.c
index 6a00f2a..75131bc 100644 (file)
--- a/drivers/net/ethernet/sfc/ef100_nic.c
+++ b/drivers/net/ethernet/sfc/ef100_nic.c
@@ -485,6 +485,36 @@ const struct efx_nic_type ef100_pf_nic_type = {
 
 };
 
+static int compare_versions(const char *a, const char *b)
+{
+       int a_major, a_minor, a_point, a_patch;
+       int b_major, b_minor, b_point, b_patch;
+       int a_matched, b_matched;
+
+       a_matched = sscanf(a, "%d.%d.%d.%d", &a_major, &a_minor, &a_point, &a_patch);
+       b_matched = sscanf(b, "%d.%d.%d.%d", &b_major, &b_minor, &b_point, &b_patch);
+
+       if (a_matched == 4 && b_matched != 4)
+               return +1;
+
+       if (a_matched != 4 && b_matched == 4)
+               return -1;
+
+       if (a_matched != 4 && b_matched != 4)
+               return 0;
+
+       if (a_major != b_major)
+               return a_major - b_major;
+
+       if (a_minor != b_minor)
+               return a_minor - b_minor;
+
+       if (a_point != b_point)
+               return a_point - b_point;
+
+       return a_patch - b_patch;
+}
+
 /*     NIC probe and remove
  */
 static int ef100_probe_main(struct efx_nic *efx)
@@ -492,6 +522,7 @@ static int ef100_probe_main(struct efx_nic *efx)
        unsigned int bar_size = resource_size(&efx->pci_dev->resource[efx->mem_bar]);
        struct net_device *net_dev = efx->net_dev;
        struct ef100_nic_data *nic_data;
+       char fw_version[32];
        int i, rc;
 
        if (WARN_ON(bar_size == 0))
@@ -562,6 +593,15 @@ static int ef100_probe_main(struct efx_nic *efx)
                goto fail;
        efx->port_num = rc;
 
+       efx_mcdi_print_fwver(efx, fw_version, sizeof(fw_version));
+       netif_dbg(efx, drv, efx->net_dev, "Firmware version %s\n", fw_version);
+
+       if (compare_versions(fw_version, "1.1.0.1000") < 0) {
+               netif_info(efx, drv, efx->net_dev, "Firmware uses old event descriptors\n");
+               rc = -EINVAL;
+               goto fail;
+       }
+
        rc = ef100_phy_probe(efx);
        if (rc)
                goto fail;