[HAL] add timer in rx_setup FSM to wait for early_link_up to be cleared.

After unplugging fiber, the early_link_up flag is cleared a bit later than the detection of link_down happens. This resulted in the tx_setup state machine trying to calibrate unplugged link. The things worked because the FSM would hang in wait_lock state and then timeout. Yet, this did not seem the best solution. So, I added timeout to wait for the early_link_up bit to be cleared

[HAL] add timer in rx_setup FSM to wait for early_link_up to be cleared.
After unplugging fiber, the early_link_up flag is cleared a bit later than the detection of link_down happens. This resulted in the tx_setup state machine trying to calibrate unplugged link. The things worked because the FSM would hang in wait_lock state and then timeout. Yet, this did not seem the best solution. So, I added timeout to wait for the early_link_up bit to be cleared
1d9f2386 · Maciej Lipinski · 072d01aa · 1d9f2386 · 1d9f2386
Commit 1d9f2386 authored Sep 06, 2019 by Maciej Lipinski
Hide whitespace changes
Inline Side-by-side

Showing with 24 additions and 4 deletions

hal_shmem.h userspace/libwr/include/libwr/hal_shmem.h +1 -0

hal_port_fsm_rx.c userspace/wrsw_hal/hal_port_fsm_rx.c +23 -4

No files found.
--- a/userspace/libwr/include/libwr/hal_shmem.h
+++ b/userspace/libwr/include/libwr/hal_shmem.h
@@ -86,6 +86,7 @@ typedef struct {
 typedef struct {
 	timeout_t link_timeout;
 	timeout_t align_timeout;
+        timeout_t earlyup_timeout;
 	int attempts;
 }halPortLpdcRx_t;


--- a/userspace/wrsw_hal/hal_port_fsm_rx.c
+++ b/userspace/wrsw_hal/hal_port_fsm_rx.c
@@ -125,7 +125,7 @@ static __inline__ void updatePllState(struct hal_port_state * ps) {
 */
 static int _hal_port_rx_setup_state_start(void *vpfg, int eventMsk, int isNewState) {
 	struct hal_port_state * ps=((halPortFsmGen_t *)vpfg)->ps;
-
+	halPortLpdcRx_t *rxSetup=ps->lpdc.rxSetup;

 	// prevent RX FSM from starting up when the TX path calibration of the port is
 	// not completed.	
@@ -138,14 +138,17 @@ static int _hal_port_rx_setup_state_start(void *vpfg, int eventMsk, int isNewSta
        }

 	if ( ps->lpdc.isSupported ) {
+		/* Wait a bit to make sure early_link_up is resetted. This
+		   timeout is initialized in hal_port_rx_setup_init_fsm(),
+		   see detailed description there. */
+		if (! libwr_tmo_expired(&rxSetup->earlyup_timeout)) {
+			return 0;
+		}
 		// LPDC support
 		pcs_writel(ps, MDIO_LPC_CTRL_TX_ENABLE |
 			      MDIO_LPC_CTRL_DMTD_SOURCE_RXRECCLK,
 			      MDIO_LPC_CTRL);
-
 		if( _isHalRxSetupEventEarlyLinkUp(eventMsk)) {
-			halPortLpdcRx_t *rxSetup=ps->lpdc.rxSetup;
-
 			rxSetup->attempts=0;
 			rts_enable_ptracker(ps->hw_index, 0);
 			_fireState(vpfg,HAL_PORT_RX_SETUP_STATE_RESET_PCS);
@@ -310,6 +313,22 @@ void hal_port_rx_setup_init_fsm(struct hal_port_state * ps ) {
 	_portFsm.ps=ps;
 	_portFsm.st=&ps->lpdc.rxSetupStates;
 	ps->lpdc.rxSetupStates.state=-1;
+	if ( ps->lpdc.isSupported ) {
+		/* This timeout is needed when link goes down. In such case
+		   the link_down flag is set earlier than the early_link_up
+		   flag is reseted. So, after the link goes down, we need to
+		   wait some time before executing the rx_setup FSM. Without
+		   such a wait, after unplugging fiber, the rx_setup FSM is
+		   started and then hangs in in wait_lock state until
+		   link_timeout fires.
+		   NOTE: We do the initialization of timeout here (and not in
+		   the _hal_port_rx_setup_state_start() when isNewState=1) for
+		   a reason. If it was done in _hal_port_rx_setup_state_start(),
+		   the timeout would also kick in when the START state is
+		   entered from WAIT_LOCK*/
+		halPortLpdcRx_t *rxSetup=ps->lpdc.rxSetup;
+		libwr_tmo_init(&rxSetup->earlyup_timeout, 10, 1);
+        }
 	_fireState(&_portFsm,HAL_PORT_RX_SETUP_STATE_START);
 }