net: dsa: bcm_sf2: Restore CFP rules during system resume

The hardware can lose its context during system suspend, and depending
on the switch generation (7445 vs. 7278), while the rules are still
there, they will have their valid bit cleared (because that's the
fastest way for the HW to reset things). Just make sure we re-apply them
coming back from resume. The 7445 switch is an older version of the core
that has some quirky RAM technology requiring a delete then re-inser to
guarantee the RAM entries are properly latched.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/bcm_sf2.c

@@ -710,6 +710,10 @@ static int bcm_sf2_sw_resume(struct dsa_switch *ds)
 		return ret;
 	}
 
+	ret = bcm_sf2_cfp_resume(ds);
+	if (ret)
+		return ret;
+
 	if (priv->hw_params.num_gphy == 1)
 		bcm_sf2_gphy_enable_set(ds, true);
 

drivers/net/dsa/bcm_sf2.h

@@ -215,5 +215,6 @@ int bcm_sf2_set_rxnfc(struct dsa_switch *ds, int port,
 		      struct ethtool_rxnfc *nfc);
 int bcm_sf2_cfp_rst(struct bcm_sf2_priv *priv);
 void bcm_sf2_cfp_exit(struct dsa_switch *ds);
+int bcm_sf2_cfp_resume(struct dsa_switch *ds);
 
 #endif /* __BCM_SF2_H */

drivers/net/dsa/bcm_sf2_cfp.c

@@ -1443,3 +1443,39 @@ void bcm_sf2_cfp_exit(struct dsa_switch *ds)
 	list_for_each_entry_safe_reverse(rule, n, &priv->cfp.rules_list, next)
 		bcm_sf2_cfp_rule_del(priv, rule->port, rule->fs.location);
 }
+
+int bcm_sf2_cfp_resume(struct dsa_switch *ds)
+{
+	struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
+	struct cfp_rule *rule;
+	int ret = 0;
+	u32 reg;
+
+	if (list_empty(&priv->cfp.rules_list))
+		return ret;
+
+	reg = core_readl(priv, CORE_CFP_CTL_REG);
+	reg &= ~CFP_EN_MAP_MASK;
+	core_writel(priv, reg, CORE_CFP_CTL_REG);
+
+	ret = bcm_sf2_cfp_rst(priv);
+	if (ret)
+		return ret;
+
+	list_for_each_entry(rule, &priv->cfp.rules_list, next) {
+		ret = bcm_sf2_cfp_rule_remove(priv, rule->port,
+					      rule->fs.location);
+		if (ret) {
+			dev_err(ds->dev, "failed to remove rule\n");
+			return ret;
+		}
+
+		ret = bcm_sf2_cfp_rule_insert(ds, rule->port, &rule->fs);
+		if (ret) {
+			dev_err(ds->dev, "failed to restore rule\n");
+			return ret;
+		}
+	};
+
+	return ret;
+}