Drop driver defined stmmac_fpe_state, and switch to common
ethtool_mm_verify_status for local TX verification status.

Local side and remote side verification processes are completely
independent. There is no reason at all to keep a local state and
a remote state.

Add a spinlock to avoid races among ISR, workqueue, link update
and register configuration.

Signed-off-by: Furong Xu <redacted>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac.h  |  21 +--
 .../net/ethernet/stmicro/stmmac/stmmac_main.c | 172 ++++++++++--------
 .../net/ethernet/stmicro/stmmac/stmmac_tc.c   |   6 -
 3 files changed, 102 insertions(+), 97 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index 458d6b16ce21..407b59f2783f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h

@@ -146,14 +146,6 @@ struct stmmac_channel {
 	u32 index;
 };
 
-/* FPE link state */
-enum stmmac_fpe_state {
-	FPE_STATE_OFF = 0,
-	FPE_STATE_CAPABLE = 1,
-	FPE_STATE_ENTERING_ON = 2,
-	FPE_STATE_ON = 3,
-};
-
 /* FPE link-partner hand-shaking mPacket type */
 enum stmmac_mpacket_type {
 	MPACKET_VERIFY = 0,

@@ -166,11 +158,16 @@ enum stmmac_fpe_task_state_t {
 };
 
 struct stmmac_fpe_cfg {
-	bool enable;				/* FPE enable */
-	bool hs_enable;				/* FPE handshake enable */
-	enum stmmac_fpe_state lp_fpe_state;	/* Link Partner FPE state */
-	enum stmmac_fpe_state lo_fpe_state;	/* Local station FPE state */
+	/* Serialize access to MAC Merge state between ethtool requests
+	 * and link state updates.
+	 */
+	spinlock_t lock;
+
 	u32 fpe_csr;				/* MAC_FPE_CTRL_STS reg cache */
+	u32 verify_time;			/* see ethtool_mm_state */
+	bool pmac_enabled;			/* see ethtool_mm_state */
+	bool verify_enabled;			/* see ethtool_mm_state */
+	enum ethtool_mm_verify_status status;

 };
 
 struct stmmac_tc_entry {

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 3072ad33b105..6ae95f20b24f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -969,17 +969,21 @@ static void stmmac_mac_config(struct phylink_config *config, unsigned int mode,
 static void stmmac_fpe_link_state_handle(struct stmmac_priv *priv, bool is_up)
 {
 	struct stmmac_fpe_cfg *fpe_cfg = &priv->fpe_cfg;
-	enum stmmac_fpe_state *lo_state = &fpe_cfg->lo_fpe_state;
-	enum stmmac_fpe_state *lp_state = &fpe_cfg->lp_fpe_state;
-	bool *hs_enable = &fpe_cfg->hs_enable;
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv->fpe_cfg.lock, flags);
+
+	if (!fpe_cfg->pmac_enabled)
+		goto __unlock_out;
 
-	if (is_up && *hs_enable) {
+	if (is_up && fpe_cfg->verify_enabled)
 		stmmac_fpe_send_mpacket(priv, priv->ioaddr, fpe_cfg,
 					MPACKET_VERIFY);
-	} else {
-		*lo_state = FPE_STATE_OFF;
-		*lp_state = FPE_STATE_OFF;
-	}
+	else
+		fpe_cfg->status = ETHTOOL_MM_VERIFY_STATUS_DISABLED;
+
+__unlock_out:

+	spin_unlock_irqrestore(&priv->fpe_cfg.lock, flags);
 }
 
 static void stmmac_mac_link_down(struct phylink_config *config,

@@ -4091,11 +4095,25 @@ static int stmmac_release(struct net_device *dev)
 
 	stmmac_release_ptp(priv);
 
-	pm_runtime_put(priv->device);
-
-	if (priv->dma_cap.fpesel)
+	if (priv->dma_cap.fpesel) {
 		stmmac_fpe_stop_wq(priv);
 
+		/* stmmac_ethtool_ops.begin() guarantees that all ethtool
+		 * requests to fail with EBUSY when !netif_running()
+		 *
+		 * Prepare some params here, then fpe_cfg can keep consistent
+		 * with the register states after a SW reset by __stmmac_open().
+		 */
+		priv->fpe_cfg.pmac_enabled = false;
+		priv->fpe_cfg.verify_enabled = false;
+		priv->fpe_cfg.status = ETHTOOL_MM_VERIFY_STATUS_DISABLED;
+
+		/* Reset MAC_FPE_CTRL_STS reg cache */
+		priv->fpe_cfg.fpe_csr = 0;
+	}
+
+	pm_runtime_put(priv->device);
+
 	return 0;
 }
 

@@ -5979,44 +5997,34 @@ static int stmmac_set_features(struct net_device *netdev,
 static void stmmac_fpe_event_status(struct stmmac_priv *priv, int status)
 {
 	struct stmmac_fpe_cfg *fpe_cfg = &priv->fpe_cfg;
-	enum stmmac_fpe_state *lo_state = &fpe_cfg->lo_fpe_state;
-	enum stmmac_fpe_state *lp_state = &fpe_cfg->lp_fpe_state;
-	bool *hs_enable = &fpe_cfg->hs_enable;
 
-	if (status == FPE_EVENT_UNKNOWN || !*hs_enable)
-		return;
+	spin_lock(&priv->fpe_cfg.lock);

 	}
 
 	clear_bit(__FPE_TASK_SCHED, &priv->fpe_task_state);

@@ -7535,8 +7550,8 @@ int stmmac_dvr_probe(struct device *device,
 
 	INIT_WORK(&priv->service_task, stmmac_service_task);
 
-	/* Initialize Link Partner FPE workqueue */
-	INIT_WORK(&priv->fpe_task, stmmac_fpe_lp_task);
+	/* Initialize FPE verify workqueue */
+	INIT_WORK(&priv->fpe_task, stmmac_fpe_verify_task);
 
 	/* Override with kernel parameters if supplied XXX CRS XXX
 	 * this needs to have multiple instances

@@ -7702,6 +7717,12 @@ int stmmac_dvr_probe(struct device *device,
 
 	mutex_init(&priv->lock);
 
+	spin_lock_init(&priv->fpe_cfg.lock);
+	priv->fpe_cfg.pmac_enabled = false;

+	priv->fpe_cfg.verify_enabled = false;
+	priv->fpe_cfg.status = ETHTOOL_MM_VERIFY_STATUS_DISABLED;
+
 	/* If a specific clk_csr value is passed from the platform
 	 * this means that the CSR Clock Range selection cannot be
 	 * changed at run-time and it is fixed. Viceversa the driver'll try to

@@ -7875,15 +7896,8 @@ int stmmac_suspend(struct device *dev)
 	}
 	rtnl_unlock();
 
-	if (priv->dma_cap.fpesel) {
-		/* Disable FPE */
-		stmmac_fpe_configure(priv, priv->ioaddr,
-				     &priv->fpe_cfg,
-				     priv->plat->tx_queues_to_use,
-				     priv->plat->rx_queues_to_use, false);
-
+	if (priv->dma_cap.fpesel)
 		stmmac_fpe_stop_wq(priv);
-	}
 
 	priv->speed = SPEED_UNKNOWN;
 	return 0;

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
index b0cc45331ff7..783829a6479c 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c

@@ -1063,11 +1063,6 @@ static int tc_taprio_configure(struct stmmac_priv *priv,
 		return -EOPNOTSUPP;
 	}
 
-	/* Actual FPE register configuration will be done after FPE handshake
-	 * is success.
-	 */
-	priv->fpe_cfg.enable = fpe;
-
 	ret = stmmac_est_configure(priv, priv, priv->est,
 				   priv->plat->clk_ptp_rate);
 	mutex_unlock(&priv->est_lock);

@@ -1094,7 +1089,6 @@ static int tc_taprio_configure(struct stmmac_priv *priv,
 		mutex_unlock(&priv->est_lock);
 	}
 
-	priv->fpe_cfg.enable = false;
 	stmmac_fpe_configure(priv, priv->ioaddr,
 			     &priv->fpe_cfg,
 			     priv->plat->tx_queues_to_use,