Merge branch 'stmmac-xpcs-eee'

Michael Sit Wei Hong says:

====================
Introducing support for DWC xpcs Energy Efficient Ethernet

The goal of this patch set is to enable EEE in the xpcs so that when
EEE is enabled, the MAC-->xpcs-->PHY have all the EEE related
configurations enabled.

Patch 1 adds the functions to enable EEE in the xpcs and sets it to
transparent mode.
Patch 2 adds the callbacks to configure the xpcs EEE mode.

The results are tested by checking the lpi counters of the tx and rx
path of the interface. When EEE is enabled, the lpi counters should
increament as it enters and exits lpi states.

host@EHL$ ethtool --show-eee enp0s30f4
EEE Settings for enp0s30f4:
        EEE status: disabled
        Tx LPI: disabled
        Supported EEE link modes:  100baseT/Full
                                   1000baseT/Full
        Advertised EEE link modes:  Not reported
        Link partner advertised EEE link modes:  100baseT/Full
                                                 1000baseT/Full
host@EHL$ ethtool -S enp0s30f4 | grep lpi
     irq_tx_path_in_lpi_mode_n: 0
     irq_tx_path_exit_lpi_mode_n: 0
     irq_rx_path_in_lpi_mode_n: 0
     irq_rx_path_exit_lpi_mode_n: 0
host@EHL$ ethtool --set-eee enp0s30f4 eee on
host@EHL$ [  110.265154] intel-eth-pci 0000:00:1e.4 enp0s30f4: Link is Down
[  112.315155] intel-eth-pci 0000:00:1e.4 enp0s30f4: Link is Up - 1Gbps/Full - flow control off
[  112.324612] IPv6: ADDRCONF(NETDEV_CHANGE): enp0s30f4: link becomes ready
host@EHL$ ethtool --show-eee enp0s30f4
EEE Settings for enp0s30f4:
        EEE status: enabled - active
        Tx LPI: 1000000 (us)
        Supported EEE link modes:  100baseT/Full
                                   1000baseT/Full
        Advertised EEE link modes:  100baseT/Full
                                    1000baseT/Full
        Link partner advertised EEE link modes:  100baseT/Full
                                                 1000baseT/Full
host@EHL$ ethtool -S enp0s30f4 | grep lpi
     irq_tx_path_in_lpi_mode_n: 6
     irq_tx_path_exit_lpi_mode_n: 5
     irq_rx_path_in_lpi_mode_n: 7
     irq_rx_path_exit_lpi_mode_n: 6
host@EHL$ ping 192.168.1.1
PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.
64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=1.02 ms
64 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=0.510 ms
64 bytes from 192.168.1.1: icmp_seq=3 ttl=64 time=0.489 ms
64 bytes from 192.168.1.1: icmp_seq=4 ttl=64 time=0.484 ms
64 bytes from 192.168.1.1: icmp_seq=5 ttl=64 time=0.504 ms
64 bytes from 192.168.1.1: icmp_seq=6 ttl=64 time=0.466 ms
64 bytes from 192.168.1.1: icmp_seq=7 ttl=64 time=0.529 ms
64 bytes from 192.168.1.1: icmp_seq=8 ttl=64 time=0.519 ms
64 bytes from 192.168.1.1: icmp_seq=9 ttl=64 time=0.518 ms
64 bytes from 192.168.1.1: icmp_seq=10 ttl=64 time=0.501 ms

--- 192.168.1.1 ping statistics ---
10 packets transmitted, 10 received, 0% packet loss, time 9216ms
rtt min/avg/max/mdev = 0.466/0.553/1.018/0.155 ms
host@EHL$ ethtool -S enp0s30f4 | grep lpi
     irq_tx_path_in_lpi_mode_n: 22
     irq_tx_path_exit_lpi_mode_n: 21
     irq_rx_path_in_lpi_mode_n: 21
     irq_rx_path_exit_lpi_mode_n: 20
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/dwmac-intel.c

@@ -429,6 +429,17 @@ static int intel_mgbe_common_data(struct pci_dev *pdev,
 	plat->force_sf_dma_mode = 0;
 	plat->tso_en = 1;
 
+	/* Multiplying factor to the clk_eee_i clock time
+	 * period to make it closer to 100 ns. This value
+	 * should be programmed such that the clk_eee_time_period *
+	 * (MULT_FACT_100NS + 1) should be within 80 ns to 120 ns
+	 * clk_eee frequency is 19.2Mhz
+	 * clk_eee_time_period is 52ns
+	 * 52ns * (1 + 1) = 104ns
+	 * MULT_FACT_100NS = 1
+	 */
+	plat->mult_fact_100ns = 1;
+
 	plat->rx_sched_algorithm = MTL_RX_ALGORITHM_SP;
 
 	for (i = 0; i < plat->rx_queues_to_use; i++) {

drivers/net/ethernet/stmicro/stmmac/hwif.h

@@ -623,6 +623,8 @@ struct stmmac_mmc_ops {
 	stmmac_do_callback(__priv, xpcs, link_up, __args)
 #define stmmac_xpcs_probe(__priv, __args...) \
 	stmmac_do_callback(__priv, xpcs, probe, __args)
+#define stmmac_xpcs_config_eee(__priv, __args...) \
+	stmmac_do_callback(__priv, xpcs, config_eee, __args)
 
 struct stmmac_regs_off {
 	u32 ptp_off;

drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c

@@ -720,6 +720,12 @@ static int stmmac_ethtool_op_set_eee(struct net_device *dev,
 		netdev_warn(priv->dev,
 			    "Setting EEE tx-lpi is not supported\n");
 
+	ret = stmmac_xpcs_config_eee(priv, &priv->hw->xpcs_args,
+				     priv->plat->mult_fact_100ns,
+				     edata->eee_enabled);
+	if (ret)
+		return ret;
+
 	if (!edata->eee_enabled)
 		stmmac_disable_eee_mode(priv);
 

drivers/net/pcs/pcs-xpcs.c

@@ -63,6 +63,9 @@
 #define DW_VR_MII_DIG_CTRL1		0x8000
 #define DW_VR_MII_AN_CTRL		0x8001
 #define DW_VR_MII_AN_INTR_STS		0x8002
+/* EEE Mode Control Register */
+#define DW_VR_MII_EEE_MCTRL0		0x8006
+#define DW_VR_MII_EEE_MCTRL1		0x800b
 
 /* VR_MII_DIG_CTRL1 */
 #define DW_VR_MII_DIG_CTRL1_MAC_AUTO_SW		BIT(9)
@@ -86,6 +89,20 @@
 #define DW_VR_MII_C37_ANSGM_SP_1000		0x2
 #define DW_VR_MII_C37_ANSGM_SP_LNKSTS		BIT(4)
 
+/* VR MII EEE Control 0 defines */
+#define DW_VR_MII_EEE_LTX_EN		BIT(0)  /* LPI Tx Enable */
+#define DW_VR_MII_EEE_LRX_EN		BIT(1)  /* LPI Rx Enable */
+#define DW_VR_MII_EEE_TX_QUIET_EN		BIT(2)  /* Tx Quiet Enable */
+#define DW_VR_MII_EEE_RX_QUIET_EN		BIT(3)  /* Rx Quiet Enable */
+#define DW_VR_MII_EEE_TX_EN_CTRL		BIT(4)  /* Tx Control Enable */
+#define DW_VR_MII_EEE_RX_EN_CTRL		BIT(7)  /* Rx Control Enable */
+
+#define DW_VR_MII_EEE_MULT_FACT_100NS_SHIFT	8
+#define DW_VR_MII_EEE_MULT_FACT_100NS		GENMASK(11, 8)
+
+/* VR MII EEE Control 1 defines */
+#define DW_VR_MII_EEE_TRN_LPI		BIT(0)	/* Transparent Mode Enable */
+
 static const int xpcs_usxgmii_features[] = {
 	ETHTOOL_LINK_MODE_Pause_BIT,
 	ETHTOOL_LINK_MODE_Asym_Pause_BIT,
@@ -650,6 +667,39 @@ static int xpcs_validate(struct mdio_xpcs_args *xpcs,
 	return 0;
 }
 
+static int xpcs_config_eee(struct mdio_xpcs_args *xpcs, int mult_fact_100ns,
+			   int enable)
+{
+	int ret;
+
+	if (enable) {
+	/* Enable EEE */
+		ret = DW_VR_MII_EEE_LTX_EN | DW_VR_MII_EEE_LRX_EN |
+		      DW_VR_MII_EEE_TX_QUIET_EN | DW_VR_MII_EEE_RX_QUIET_EN |
+		      DW_VR_MII_EEE_TX_EN_CTRL | DW_VR_MII_EEE_RX_EN_CTRL |
+		      mult_fact_100ns << DW_VR_MII_EEE_MULT_FACT_100NS_SHIFT;
+	} else {
+		ret = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_EEE_MCTRL0);
+		if (ret < 0)
+			return ret;
+		ret &= ~(DW_VR_MII_EEE_LTX_EN | DW_VR_MII_EEE_LRX_EN |
+		       DW_VR_MII_EEE_TX_QUIET_EN | DW_VR_MII_EEE_RX_QUIET_EN |
+		       DW_VR_MII_EEE_TX_EN_CTRL | DW_VR_MII_EEE_RX_EN_CTRL |
+		       DW_VR_MII_EEE_MULT_FACT_100NS);
+	}
+
+	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_EEE_MCTRL0, ret);
+	if (ret < 0)
+		return ret;
+
+	ret = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_EEE_MCTRL1);
+	if (ret < 0)
+		return ret;
+
+	ret |= DW_VR_MII_EEE_TRN_LPI;
+	return xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_EEE_MCTRL1, ret);
+}
+
 static int xpcs_config_aneg_c37_sgmii(struct mdio_xpcs_args *xpcs)
 {
 	int ret;
@@ -908,6 +958,7 @@ static struct mdio_xpcs_ops xpcs_ops = {
 	.get_state = xpcs_get_state,
 	.link_up = xpcs_link_up,
 	.probe = xpcs_probe,
+	.config_eee = xpcs_config_eee,
 };
 
 struct mdio_xpcs_ops *mdio_xpcs_get_ops(void)

include/linux/pcs/pcs-xpcs.h

@@ -32,6 +32,8 @@ struct mdio_xpcs_ops {
 	int (*link_up)(struct mdio_xpcs_args *xpcs, int speed,
 		       phy_interface_t interface);
 	int (*probe)(struct mdio_xpcs_args *xpcs, phy_interface_t interface);
+	int (*config_eee)(struct mdio_xpcs_args *xpcs, int mult_fact_100ns,
+			  int enable);
 };
 
 #if IS_ENABLED(CONFIG_PCS_XPCS)

include/linux/stmmac.h

@@ -223,6 +223,7 @@ struct plat_stmmacenet_data {
 	struct clk *clk_ptp_ref;
 	unsigned int clk_ptp_rate;
 	unsigned int clk_ref_rate;
+	unsigned int mult_fact_100ns;
 	s32 ptp_max_adj;
 	struct reset_control *stmmac_rst;
 	struct stmmac_axi *axi;