kernel: sfp: add Nokia SFP fix from net-next

Add Nokia GPON ONT SFP fix for tx_fault in net-next.

Signed-off-by: Scott Roberts <ttocsr@gmail.com>

1 files changed, 108 insertions, 0 deletions

diff --git a/target/linux/generic/pending-4.19/739-net-avoid-tx-fault-with-Nokia-GPON-module.patch b/target/linux/generic/pending-4.19/739-net-avoid-tx-fault-with-Nokia-GPON-module.patch
new file mode 100644
index 0000000000..b540e1dbc1
--- /dev/null
+++ b/target/linux/generic/pending-4.19/739-net-avoid-tx-fault-with-Nokia-GPON-module.patch
@@ -0,0 +1,108 @@
+From 283b211aa01bdae94dffb3121655dbb20bf237f4 Mon Sep 17 00:00:00 2001
+From: Russell King <rmk+kernel@armlinux.org.uk>
+Date: Tue, 3 Dec 2019 15:22:05 +0000
+Subject: net: sfp: avoid tx-fault with Nokia GPON module
+
+The Nokia GPON module can hold tx-fault active while it is initialising
+which can take up to 60s. Avoid this causing the module to be declared
+faulty after the SFP MSA defined non-cooled module timeout.
+
+Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
+---
+ drivers/net/phy/sfp.c | 42 ++++++++++++++++++++++++++++++------------
+ 1 file changed, 30 insertions(+), 12 deletions(-)
+
+--- a/drivers/net/phy/sfp.c
++++ b/drivers/net/phy/sfp.c
+@@ -153,10 +153,20 @@ static const enum gpiod_flags gpio_flags
+ 	GPIOD_ASIS,
+ };
+ 
+-#define T_WAIT		msecs_to_jiffies(50)
+-#define T_INIT_JIFFIES	msecs_to_jiffies(300)
+-#define T_RESET_US	10
+-#define T_FAULT_RECOVER	msecs_to_jiffies(1000)
++/* t_start_up (SFF-8431) or t_init (SFF-8472) is the time required for a
++ * non-cooled module to initialise its laser safety circuitry. We wait
++ * an initial T_WAIT period before we check the tx fault to give any PHY
++ * on board (for a copper SFP) time to initialise.
++ */
++#define T_WAIT			msecs_to_jiffies(50)
++#define T_START_UP		msecs_to_jiffies(300)
++#define T_START_UP_BAD_GPON	msecs_to_jiffies(60000)
++
++/* t_reset is the time required to assert the TX_DISABLE signal to reset
++ * an indicated TX_FAULT.
++ */
++#define T_RESET_US		10
++#define T_FAULT_RECOVER		msecs_to_jiffies(1000)
+ 
+ /* SFP module presence detection is poor: the three MOD DEF signals are
+  * the same length on the PCB, which means it's possible for MOD DEF 0 to
+@@ -216,6 +226,7 @@ struct sfp {
+ 
+ 	struct sfp_eeprom_id id;
+ 	unsigned int module_power_mW;
++	unsigned int module_t_start_up;
+ 
+ #if IS_ENABLED(CONFIG_HWMON)
+ 	struct sfp_diag diag;
+@@ -1590,6 +1601,12 @@ static int sfp_sm_mod_probe(struct sfp *
+ 	if (ret < 0)
+ 		return ret;
+ 
++	if (!memcmp(id.base.vendor_name, "ALCATELLUCENT   ", 16) &&
++	    !memcmp(id.base.vendor_pn, "3FE46541AA      ", 16))
++		sfp->module_t_start_up = T_START_UP_BAD_GPON;
++	else
++		sfp->module_t_start_up = T_START_UP;
++
+ 	return 0;
+ }
+ 
+@@ -1795,11 +1812,12 @@ static void sfp_sm_main(struct sfp *sfp,
+ 			break;
+ 
+ 		if (sfp->state & SFP_F_TX_FAULT) {
+-			/* Wait t_init before indicating that the link is up,
+-			 * provided the current state indicates no TX_FAULT. If
+-			 * TX_FAULT clears before this time, that's fine too.
++			/* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
++			 * from the TX_DISABLE deassertion for the module to
++			 * initialise, which is indicated by TX_FAULT
++			 * deasserting.
+ 			 */
+-			timeout = T_INIT_JIFFIES;
++			timeout = sfp->module_t_start_up;
+ 			if (timeout > T_WAIT)
+ 				timeout -= T_WAIT;
+ 			else
+@@ -1816,8 +1834,8 @@ static void sfp_sm_main(struct sfp *sfp,
+ 
+ 	case SFP_S_INIT:
+ 		if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
+-			/* TX_FAULT is still asserted after t_init, so assume
+-			 * there is a fault.
++			/* TX_FAULT is still asserted after t_init or
++			 * or t_start_up, so assume there is a fault.
+ 			 */
+ 			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
+ 				     sfp->sm_retries == 5);
+@@ -1836,7 +1854,7 @@ static void sfp_sm_main(struct sfp *sfp,
+ 	case SFP_S_INIT_TX_FAULT:
+ 		if (event == SFP_E_TIMEOUT) {
+ 			sfp_module_tx_fault_reset(sfp);
+-			sfp_sm_next(sfp, SFP_S_INIT, T_INIT_JIFFIES);
++			sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
+ 		}
+ 		break;
+ 
+@@ -1860,7 +1878,7 @@ static void sfp_sm_main(struct sfp *sfp,
+ 	case SFP_S_TX_FAULT:
+ 		if (event == SFP_E_TIMEOUT) {
+ 			sfp_module_tx_fault_reset(sfp);
+-			sfp_sm_next(sfp, SFP_S_REINIT, T_INIT_JIFFIES);
++			sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
+ 		}
+ 		break;
+