net: enetc: implement software lockstep for port MAC registers

Currently the enetc driver duplicates its writes to the PM0 registers
also to PM1, but it doesn't do this consistently - for example we write
to ENETC_PM0_MAXFRM but not to ENETC_PM1_MAXFRM.

Create enetc_port_mac_wr() which writes both the PM0 and PM1 register
with the same value (if frame preemption is supported on this port).
Also create enetc_port_mac_rd() which reads from PM0 - the assumption
being that PM1 contains just the same value.

This will be necessary when we enable the MAC Merge layer properly, and
the pMAC becomes operational.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/enetc/enetc.c

@@ -11,6 +11,20 @@
 #include <net/pkt_sched.h>
 #include <net/tso.h>
 
+u32 enetc_port_mac_rd(struct enetc_si *si, u32 reg)
+{
+	return enetc_port_rd(&si->hw, reg);
+}
+EXPORT_SYMBOL_GPL(enetc_port_mac_rd);
+
+void enetc_port_mac_wr(struct enetc_si *si, u32 reg, u32 val)
+{
+	enetc_port_wr(&si->hw, reg, val);
+	if (si->hw_features & ENETC_SI_F_QBU)
+		enetc_port_wr(&si->hw, reg + ENETC_PMAC_OFFSET, val);
+}
+EXPORT_SYMBOL_GPL(enetc_port_mac_wr);
+
 static int enetc_num_stack_tx_queues(struct enetc_ndev_priv *priv)
 {
 	int num_tx_rings = priv->num_tx_rings;
@@ -243,8 +257,8 @@ static int enetc_map_tx_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb)
 			if (udp)
 				val |= ENETC_PM0_SINGLE_STEP_CH;
 
-			enetc_port_wr(hw, ENETC_PM0_SINGLE_STEP, val);
-			enetc_port_wr(hw, ENETC_PM1_SINGLE_STEP, val);
+			enetc_port_mac_wr(priv->si, ENETC_PM0_SINGLE_STEP,
+					  val);
 		} else if (do_twostep_tstamp) {
 			skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
 			e_flags |= ENETC_TXBD_E_FLAGS_TWO_STEP_PTP;

drivers/net/ethernet/freescale/enetc/enetc.h

@@ -397,6 +397,8 @@ struct enetc_msg_cmd_set_primary_mac {
 extern int enetc_phc_index;
 
 /* SI common */
+u32 enetc_port_mac_rd(struct enetc_si *si, u32 reg);
+void enetc_port_mac_wr(struct enetc_si *si, u32 reg, u32 val);
 int enetc_pci_probe(struct pci_dev *pdev, const char *name, int sizeof_priv);
 void enetc_pci_remove(struct pci_dev *pdev);
 int enetc_alloc_msix(struct enetc_ndev_priv *priv);

drivers/net/ethernet/freescale/enetc/enetc_hw.h

@@ -228,7 +228,6 @@ enum enetc_bdr_type {TX, RX};
 #define ENETC_PMAC_OFFSET	0x1000
 
 #define ENETC_PM0_CMD_CFG	0x8008
-#define ENETC_PM1_CMD_CFG	0x9008
 #define ENETC_PM0_TX_EN		BIT(0)
 #define ENETC_PM0_RX_EN		BIT(1)
 #define ENETC_PM0_PROMISC	BIT(4)
@@ -247,11 +246,8 @@ enum enetc_bdr_type {TX, RX};
 
 #define ENETC_PM0_PAUSE_QUANTA	0x8054
 #define ENETC_PM0_PAUSE_THRESH	0x8064
-#define ENETC_PM1_PAUSE_QUANTA	0x9054
-#define ENETC_PM1_PAUSE_THRESH	0x9064
 
 #define ENETC_PM0_SINGLE_STEP		0x80c0
-#define ENETC_PM1_SINGLE_STEP		0x90c0
 #define ENETC_PM0_SINGLE_STEP_CH	BIT(7)
 #define ENETC_PM0_SINGLE_STEP_EN	BIT(31)
 #define ENETC_SET_SINGLE_STEP_OFFSET(v)	(((v) & 0xff) << 8)

drivers/net/ethernet/freescale/enetc/enetc_pf.c

@@ -319,24 +319,23 @@ static int enetc_vlan_rx_del_vid(struct net_device *ndev, __be16 prot, u16 vid)
 static void enetc_set_loopback(struct net_device *ndev, bool en)
 {
 	struct enetc_ndev_priv *priv = netdev_priv(ndev);
-	struct enetc_hw *hw = &priv->si->hw;
+	struct enetc_si *si = priv->si;
 	u32 reg;
 
-	reg = enetc_port_rd(hw, ENETC_PM0_IF_MODE);
+	reg = enetc_port_mac_rd(si, ENETC_PM0_IF_MODE);
 	if (reg & ENETC_PM0_IFM_RG) {
 		/* RGMII mode */
 		reg = (reg & ~ENETC_PM0_IFM_RLP) |
 		      (en ? ENETC_PM0_IFM_RLP : 0);
-		enetc_port_wr(hw, ENETC_PM0_IF_MODE, reg);
+		enetc_port_mac_wr(si, ENETC_PM0_IF_MODE, reg);
 	} else {
 		/* assume SGMII mode */
-		reg = enetc_port_rd(hw, ENETC_PM0_CMD_CFG);
+		reg = enetc_port_mac_rd(si, ENETC_PM0_CMD_CFG);
 		reg = (reg & ~ENETC_PM0_CMD_XGLP) |
 		      (en ? ENETC_PM0_CMD_XGLP : 0);
 		reg = (reg & ~ENETC_PM0_CMD_PHY_TX_EN) |
 		      (en ? ENETC_PM0_CMD_PHY_TX_EN : 0);
-		enetc_port_wr(hw, ENETC_PM0_CMD_CFG, reg);
-		enetc_port_wr(hw, ENETC_PM1_CMD_CFG, reg);
+		enetc_port_mac_wr(si, ENETC_PM0_CMD_CFG, reg);
 	}
 }
 
@@ -538,52 +537,50 @@ void enetc_reset_ptcmsdur(struct enetc_hw *hw)
 		enetc_port_wr(hw, ENETC_PTCMSDUR(tc), ENETC_MAC_MAXFRM_SIZE);
 }
 
-static void enetc_configure_port_mac(struct enetc_hw *hw)
+static void enetc_configure_port_mac(struct enetc_si *si)
 {
-	enetc_port_wr(hw, ENETC_PM0_MAXFRM,
+	struct enetc_hw *hw = &si->hw;
+
+	enetc_port_mac_wr(si, ENETC_PM0_MAXFRM,
 			  ENETC_SET_MAXFRM(ENETC_RX_MAXFRM_SIZE));
 
 	enetc_reset_ptcmsdur(hw);
 
-	enetc_port_wr(hw, ENETC_PM0_CMD_CFG, ENETC_PM0_CMD_PHY_TX_EN |
-		      ENETC_PM0_CMD_TXP	| ENETC_PM0_PROMISC);
-
-	enetc_port_wr(hw, ENETC_PM1_CMD_CFG, ENETC_PM0_CMD_PHY_TX_EN |
+	enetc_port_mac_wr(si, ENETC_PM0_CMD_CFG, ENETC_PM0_CMD_PHY_TX_EN |
 			  ENETC_PM0_CMD_TXP | ENETC_PM0_PROMISC);
 
 	/* On LS1028A, the MAC RX FIFO defaults to 2, which is too high
 	 * and may lead to RX lock-up under traffic. Set it to 1 instead,
 	 * as recommended by the hardware team.
 	 */
-	enetc_port_wr(hw, ENETC_PM0_RX_FIFO, ENETC_PM0_RX_FIFO_VAL);
+	enetc_port_mac_wr(si, ENETC_PM0_RX_FIFO, ENETC_PM0_RX_FIFO_VAL);
 }
 
-static void enetc_mac_config(struct enetc_hw *hw, phy_interface_t phy_mode)
+static void enetc_mac_config(struct enetc_si *si, phy_interface_t phy_mode)
 {
 	u32 val;
 
 	if (phy_interface_mode_is_rgmii(phy_mode)) {
-		val = enetc_port_rd(hw, ENETC_PM0_IF_MODE);
+		val = enetc_port_mac_rd(si, ENETC_PM0_IF_MODE);
 		val &= ~(ENETC_PM0_IFM_EN_AUTO | ENETC_PM0_IFM_IFMODE_MASK);
 		val |= ENETC_PM0_IFM_IFMODE_GMII | ENETC_PM0_IFM_RG;
-		enetc_port_wr(hw, ENETC_PM0_IF_MODE, val);
+		enetc_port_mac_wr(si, ENETC_PM0_IF_MODE, val);
 	}
 
 	if (phy_mode == PHY_INTERFACE_MODE_USXGMII) {
 		val = ENETC_PM0_IFM_FULL_DPX | ENETC_PM0_IFM_IFMODE_XGMII;
-		enetc_port_wr(hw, ENETC_PM0_IF_MODE, val);
+		enetc_port_mac_wr(si, ENETC_PM0_IF_MODE, val);
 	}
 }
 
-static void enetc_mac_enable(struct enetc_hw *hw, bool en)
+static void enetc_mac_enable(struct enetc_si *si, bool en)
 {
-	u32 val = enetc_port_rd(hw, ENETC_PM0_CMD_CFG);
+	u32 val = enetc_port_mac_rd(si, ENETC_PM0_CMD_CFG);
 
 	val &= ~(ENETC_PM0_TX_EN | ENETC_PM0_RX_EN);
 	val |= en ? (ENETC_PM0_TX_EN | ENETC_PM0_RX_EN) : 0;
 
-	enetc_port_wr(hw, ENETC_PM0_CMD_CFG, val);
-	enetc_port_wr(hw, ENETC_PM1_CMD_CFG, val);
+	enetc_port_mac_wr(si, ENETC_PM0_CMD_CFG, val);
 }
 
 static void enetc_configure_port_pmac(struct enetc_hw *hw)
@@ -604,7 +601,7 @@ static void enetc_configure_port(struct enetc_pf *pf)
 
 	enetc_configure_port_pmac(hw);
 
-	enetc_configure_port_mac(hw);
+	enetc_configure_port_mac(pf->si);
 
 	enetc_port_si_configure(pf->si);
 
@@ -996,14 +993,14 @@ static void enetc_pl_mac_config(struct phylink_config *config,
 {
 	struct enetc_pf *pf = phylink_to_enetc_pf(config);
 
-	enetc_mac_config(&pf->si->hw, state->interface);
+	enetc_mac_config(pf->si, state->interface);
 }
 
-static void enetc_force_rgmii_mac(struct enetc_hw *hw, int speed, int duplex)
+static void enetc_force_rgmii_mac(struct enetc_si *si, int speed, int duplex)
 {
 	u32 old_val, val;
 
-	old_val = val = enetc_port_rd(hw, ENETC_PM0_IF_MODE);
+	old_val = val = enetc_port_mac_rd(si, ENETC_PM0_IF_MODE);
 
 	if (speed == SPEED_1000) {
 		val &= ~ENETC_PM0_IFM_SSP_MASK;
@@ -1024,7 +1021,7 @@ static void enetc_force_rgmii_mac(struct enetc_hw *hw, int speed, int duplex)
 	if (val == old_val)
 		return;
 
-	enetc_port_wr(hw, ENETC_PM0_IF_MODE, val);
+	enetc_port_mac_wr(si, ENETC_PM0_IF_MODE, val);
 }
 
 static void enetc_pl_mac_link_up(struct phylink_config *config,
@@ -1036,6 +1033,7 @@ static void enetc_pl_mac_link_up(struct phylink_config *config,
 	u32 pause_off_thresh = 0, pause_on_thresh = 0;
 	u32 init_quanta = 0, refresh_quanta = 0;
 	struct enetc_hw *hw = &pf->si->hw;
+	struct enetc_si *si = pf->si;
 	struct enetc_ndev_priv *priv;
 	u32 rbmr, cmd_cfg;
 	int idx;
@@ -1047,7 +1045,7 @@ static void enetc_pl_mac_link_up(struct phylink_config *config,
 
 	if (!phylink_autoneg_inband(mode) &&
 	    phy_interface_mode_is_rgmii(interface))
-		enetc_force_rgmii_mac(hw, speed, duplex);
+		enetc_force_rgmii_mac(si, speed, duplex);
 
 	/* Flow control */
 	for (idx = 0; idx < priv->num_rx_rings; idx++) {
@@ -1083,24 +1081,21 @@ static void enetc_pl_mac_link_up(struct phylink_config *config,
 		pause_off_thresh = 1 * ENETC_MAC_MAXFRM_SIZE;
 	}
 
-	enetc_port_wr(hw, ENETC_PM0_PAUSE_QUANTA, init_quanta);
-	enetc_port_wr(hw, ENETC_PM1_PAUSE_QUANTA, init_quanta);
-	enetc_port_wr(hw, ENETC_PM0_PAUSE_THRESH, refresh_quanta);
-	enetc_port_wr(hw, ENETC_PM1_PAUSE_THRESH, refresh_quanta);
+	enetc_port_mac_wr(si, ENETC_PM0_PAUSE_QUANTA, init_quanta);
+	enetc_port_mac_wr(si, ENETC_PM0_PAUSE_THRESH, refresh_quanta);
 	enetc_port_wr(hw, ENETC_PPAUONTR, pause_on_thresh);
 	enetc_port_wr(hw, ENETC_PPAUOFFTR, pause_off_thresh);
 
-	cmd_cfg = enetc_port_rd(hw, ENETC_PM0_CMD_CFG);
+	cmd_cfg = enetc_port_mac_rd(si, ENETC_PM0_CMD_CFG);
 
 	if (rx_pause)
 		cmd_cfg &= ~ENETC_PM0_PAUSE_IGN;
 	else
 		cmd_cfg |= ENETC_PM0_PAUSE_IGN;
 
-	enetc_port_wr(hw, ENETC_PM0_CMD_CFG, cmd_cfg);
-	enetc_port_wr(hw, ENETC_PM1_CMD_CFG, cmd_cfg);
+	enetc_port_mac_wr(si, ENETC_PM0_CMD_CFG, cmd_cfg);
 
-	enetc_mac_enable(hw, true);
+	enetc_mac_enable(si, true);
 }
 
 static void enetc_pl_mac_link_down(struct phylink_config *config,
@@ -1109,7 +1104,7 @@ static void enetc_pl_mac_link_down(struct phylink_config *config,
 {
 	struct enetc_pf *pf = phylink_to_enetc_pf(config);
 
-	enetc_mac_enable(&pf->si->hw, false);
+	enetc_mac_enable(pf->si, false);
 }
 
 static const struct phylink_mac_ops enetc_mac_phylink_ops = {