net: sfp: fix PHY discovery for FS SFP-10G-T module

Commit 2f3ce7a56c6e ("net: sfp: rework the RollBall PHY waiting code")
changed the long wait before accessing RollBall / FS modules into
probing for PHY every 1 second, and trying 25 times.

Wei Lei reports that this does not work correctly on FS modules: when
initializing, they may report values different from 0xffff in PHY ID
registers for some MMDs, causing get_phy_c45_ids() to find some bogus
MMD.

Fix this by adding the module_t_wait member back, and setting it to 4
seconds for FS modules.

Fixes: 2f3ce7a56c6e ("net: sfp: rework the RollBall PHY waiting code")
Reported-by: Wei Lei <quic_leiwei@quicinc.com>
Signed-off-by: Marek Behún <kabel@kernel.org>
Tested-by: Lei Wei <quic_leiwei@quicinc.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
index 3780a96d2caa8fd55e85ba9d8e1dc8f3c8820ed8..f75c9eb3958ef01e762bcfe1b790c635e1c749cf 100644 (file)
--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c
@@ -274,6 +274,7 @@ struct sfp {
        struct sfp_eeprom_id id;
        unsigned int module_power_mW;
        unsigned int module_t_start_up;
+       unsigned int module_t_wait;
        unsigned int phy_t_retry;
 
        unsigned int rate_kbd;
@@ -388,6 +389,12 @@ static void sfp_fixup_fs_10gt(struct sfp *sfp)
 {
        sfp_fixup_10gbaset_30m(sfp);
        sfp_fixup_rollball(sfp);
+
+       /* The RollBall fixup is not enough for FS modules, the AQR chip inside
+        * them does not return 0xffff for PHY ID registers in all MMDs for the
+        * while initializing. They need a 4 second wait before accessing PHY.
+        */
+       sfp->module_t_wait = msecs_to_jiffies(4000);
 }
 
 static void sfp_fixup_halny_gsfp(struct sfp *sfp)
@@ -2329,6 +2336,7 @@ static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
                mask |= SFP_F_RS1;
 
        sfp->module_t_start_up = T_START_UP;
+       sfp->module_t_wait = T_WAIT;
        sfp->phy_t_retry = T_PHY_RETRY;
 
        sfp->state_ignore_mask = 0;
@@ -2566,9 +2574,10 @@ static void sfp_sm_main(struct sfp *sfp, unsigned int event)
 
                /* We need to check the TX_FAULT state, which is not defined
                 * while TX_DISABLE is asserted. The earliest we want to do
-                * anything (such as probe for a PHY) is 50ms.
+                * anything (such as probe for a PHY) is 50ms (or more on
+                * specific modules).
                 */
-               sfp_sm_next(sfp, SFP_S_WAIT, T_WAIT);
+               sfp_sm_next(sfp, SFP_S_WAIT, sfp->module_t_wait);
                break;
 
        case SFP_S_WAIT:
@@ -2582,8 +2591,8 @@ static void sfp_sm_main(struct sfp *sfp, unsigned int event)
                         * deasserting.
                         */
                        timeout = sfp->module_t_start_up;
-                       if (timeout > T_WAIT)
-                               timeout -= T_WAIT;
+                       if (timeout > sfp->module_t_wait)
+                               timeout -= sfp->module_t_wait;
                        else
                                timeout = 1;