sfc: SFT9001: Add cable diagnostics

The SFT9001 firmware implements cable diagnostics; run those and
include their results in a self-test.  In case of a cable fault, do
not fail the self-test as a whole; only faults in the NIC should cause
that.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 107 insertions, 8 deletions

diff --git a/drivers/net/sfc/tenxpress.c b/drivers/net/sfc/tenxpress.c
index bd204820e18..b9768760fae 100644
--- a/drivers/net/sfc/tenxpress.c
+++ b/drivers/net/sfc/tenxpress.c
@@ -106,6 +106,25 @@
 #define PMA_PMD_SPEED_LBN        4
 #define PMA_PMD_SPEED_WIDTH      4
 
+/* Cable diagnostics - SFT9001 only */
+#define PMA_PMD_CDIAG_CTRL_REG  49213
+#define CDIAG_CTRL_IMMED_LBN    15
+#define CDIAG_CTRL_BRK_LINK_LBN 12
+#define CDIAG_CTRL_IN_PROG_LBN  11
+#define CDIAG_CTRL_LEN_UNIT_LBN 10
+#define CDIAG_CTRL_LEN_METRES   1
+#define PMA_PMD_CDIAG_RES_REG   49174
+#define CDIAG_RES_A_LBN         12
+#define CDIAG_RES_B_LBN         8
+#define CDIAG_RES_C_LBN         4
+#define CDIAG_RES_D_LBN         0
+#define CDIAG_RES_WIDTH         4
+#define CDIAG_RES_OPEN          2
+#define CDIAG_RES_OK            1
+#define CDIAG_RES_INVALID       0
+/* Set of 4 registers for pairs A-D */
+#define PMA_PMD_CDIAG_LEN_REG   49175
+
 /* Serdes control registers - SFT9001 only */
 #define PMA_PMD_CSERDES_CTRL_REG 64258
 /* Set the 156.25 MHz output to 312.5 MHz to drive Falcon's XMAC */
@@ -654,12 +673,12 @@ void tenxpress_phy_blink(struct efx_nic *efx, bool blink)
                             PMA_PMD_LED_OVERR_REG, reg);
 }
 
-static const char *const tenxpress_test_names[] = {
+static const char *const sfx7101_test_names[] = {
         "bist"
 };
 
 static int
-tenxpress_run_tests(struct efx_nic *efx, int *results, unsigned flags)
+sfx7101_run_tests(struct efx_nic *efx, int *results, unsigned flags)
 {
         int rc;
 
@@ -672,6 +691,86 @@ tenxpress_run_tests(struct efx_nic *efx, int *results, unsigned flags)
         return rc;
 }
 
+static const char *const sft9001_test_names[] = {
+        "bist",
+        "cable.pairA.status",
+        "cable.pairB.status",
+        "cable.pairC.status",
+        "cable.pairD.status",
+        "cable.pairA.length",
+        "cable.pairB.length",
+        "cable.pairC.length",
+        "cable.pairD.length",
+};
+
+static int sft9001_run_tests(struct efx_nic *efx, int *results, unsigned flags)
+{
+        struct ethtool_cmd ecmd;
+        int phy_id = efx->mii.phy_id;
+        int rc = 0, rc2, i, res_reg;
+
+        if (!(flags & ETH_TEST_FL_OFFLINE))
+                return 0;
+
+        efx->phy_op->get_settings(efx, &ecmd);
+
+        /* Initialise cable diagnostic results to unknown failure */
+        for (i = 1; i < 9; ++i)
+                results[i] = -1;
+
+        /* Run cable diagnostics; wait up to 5 seconds for them to complete.
+         * A cable fault is not a self-test failure, but a timeout is. */
+        mdio_clause45_write(efx, phy_id, MDIO_MMD_PMAPMD,
+                            PMA_PMD_CDIAG_CTRL_REG,
+                            (1 << CDIAG_CTRL_IMMED_LBN) |
+                            (1 << CDIAG_CTRL_BRK_LINK_LBN) |
+                            (CDIAG_CTRL_LEN_METRES << CDIAG_CTRL_LEN_UNIT_LBN));
+        i = 0;
+        while (mdio_clause45_read(efx, phy_id, MDIO_MMD_PMAPMD,
+                                  PMA_PMD_CDIAG_CTRL_REG) &
+               (1 << CDIAG_CTRL_IN_PROG_LBN)) {
+                if (++i == 50) {
+                        rc = -ETIMEDOUT;
+                        goto reset;
+                }
+                msleep(100);
+        }
+        res_reg = mdio_clause45_read(efx, efx->mii.phy_id, MDIO_MMD_PMAPMD,
+                                     PMA_PMD_CDIAG_RES_REG);
+        for (i = 0; i < 4; i++) {
+                int pair_res =
+                        (res_reg >> (CDIAG_RES_A_LBN - i * CDIAG_RES_WIDTH))
+                        & ((1 << CDIAG_RES_WIDTH) - 1);
+                int len_reg = mdio_clause45_read(efx, efx->mii.phy_id,
+                                                 MDIO_MMD_PMAPMD,
+                                                 PMA_PMD_CDIAG_LEN_REG + i);
+                if (pair_res == CDIAG_RES_OK)
+                        results[1 + i] = 1;
+                else if (pair_res == CDIAG_RES_INVALID)
+                        results[1 + i] = -1;
+                else
+                        results[1 + i] = -pair_res;
+                if (pair_res != CDIAG_RES_INVALID &&
+                    pair_res != CDIAG_RES_OPEN &&
+                    len_reg != 0xffff)
+                        results[5 + i] = len_reg;
+        }
+
+        /* We must reset to exit cable diagnostic mode.  The BIST will
+         * also run when we do this. */
+reset:
+        rc2 = tenxpress_special_reset(efx);
+        results[0] = rc2 ? -1 : 1;
+        if (!rc)
+                rc = rc2;
+
+        rc2 = efx->phy_op->set_settings(efx, &ecmd);
+        if (!rc)
+                rc = rc2;
+
+        return rc;
+}
+
 static u32 tenxpress_get_xnp_lpa(struct efx_nic *efx)
 {
         int phy = efx->mii.phy_id;
@@ -784,9 +883,9 @@ struct efx_phy_operations falcon_sfx7101_phy_ops = {
         .clear_interrupt  = efx_port_dummy_op_void,
         .get_settings     = sfx7101_get_settings,
         .set_settings     = mdio_clause45_set_settings,
-        .num_tests        = ARRAY_SIZE(tenxpress_test_names),
-        .test_names       = tenxpress_test_names,
-        .run_tests        = tenxpress_run_tests,
+        .num_tests        = ARRAY_SIZE(sfx7101_test_names),
+        .test_names       = sfx7101_test_names,
+        .run_tests        = sfx7101_run_tests,
         .mmds             = TENXPRESS_REQUIRED_DEVS,
         .loopbacks        = SFX7101_LOOPBACKS,
 };
@@ -801,9 +900,9 @@ struct efx_phy_operations falcon_sft9001_phy_ops = {
         .get_settings     = sft9001_get_settings,
         .set_settings     = sft9001_set_settings,
         .set_xnp_advertise = sft9001_set_xnp_advertise,
-        .num_tests        = ARRAY_SIZE(tenxpress_test_names),
-        .test_names       = tenxpress_test_names,
-        .run_tests        = tenxpress_run_tests,
+        .num_tests        = ARRAY_SIZE(sft9001_test_names),
+        .test_names       = sft9001_test_names,
+        .run_tests        = sft9001_run_tests,
         .mmds             = TENXPRESS_REQUIRED_DEVS,
         .loopbacks        = SFT9001_LOOPBACKS,
 };