[PATCH net-next v2] net: dsa: mt7530: Add support for EEE features

["René van Dorst" <opensource@vdorst.com>]

This patch adds EEE support.

Signed-off-by: René van Dorst <opensource@vdorst.com>
---
v1 -> v2:
- Refactor the mt753x_{get,set}_mac_eee().
  As DENQ Qingfang mentioned, most things are set else were.
  These functions only set/report the LPI timeout value/LPI timeout enable bit.
- Removed the variable "eee_enabled", don't need too track the EEE status.
- Refactor mt753x_phylink_mac_link_up().
  phy_init_eee() reports is the EEE is active, this function also checks
  the PHY, duplex and broken DTS modes.
  When active set the MAC EEE bit based on the speed.
- Add {GET,SET)_LPI_THRESH(x) macro
- PMCR_FORCE_EEE1G | PMCR_FORCE_EEE100 are now placed in the right MASK variable

 drivers/net/dsa/mt7530.c | 43 ++++++++++++++++++++++++++++++++++++++++
 drivers/net/dsa/mt7530.h | 14 ++++++++++++-
 2 files changed, 56 insertions(+), 1 deletion(-)

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 2bd1bab71497..96f7c9eede35 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -2570,6 +2570,17 @@ static void mt753x_phylink_mac_link_up(struct dsa_switch *ds, int port,
 			mcr |= PMCR_RX_FC_EN;
 	}
 
+	if (mode == MLO_AN_PHY && phydev && phy_init_eee(phydev, 0) >= 0) {
+		switch (speed) {
+		case SPEED_1000:
+			mcr |= PMCR_FORCE_EEE1G;
+			break;
+		case SPEED_100:
+			mcr |= PMCR_FORCE_EEE100;
+			break;
+		}
+	}
+
 	mt7530_set(priv, MT7530_PMCR_P(port), mcr);
 }
 
@@ -2800,6 +2811,36 @@ mt753x_phy_write(struct dsa_switch *ds, int port, int regnum, u16 val)
 	return priv->info->phy_write(ds, port, regnum, val);
 }
 
+static int mt753x_get_mac_eee(struct dsa_switch *ds, int port,
+			      struct ethtool_eee *e)
+{
+	struct mt7530_priv *priv = ds->priv;
+	u32 eeecr = mt7530_read(priv, MT7530_PMEEECR_P(port));
+
+	e->tx_lpi_enabled = !(eeecr & LPI_MODE_EN);
+	e->tx_lpi_timer = GET_LPI_THRESH(eeecr);
+
+	return 0;
+}
+
+static int mt753x_set_mac_eee(struct dsa_switch *ds, int port,
+			      struct ethtool_eee *e)
+{
+	struct mt7530_priv *priv = ds->priv;
+	u32 set, mask = LPI_THRESH_MASK | LPI_MODE_EN;
+
+	if (e->tx_lpi_timer > 0xFFF)
+		return -EINVAL;
+
+	set = SET_LPI_THRESH(e->tx_lpi_timer);
+	if (!e->tx_lpi_enabled)
+		/* Force LPI Mode without a delay */
+		set |= LPI_MODE_EN;
+	mt7530_rmw(priv, MT7530_PMEEECR_P(port), mask, set);
+
+	return 0;
+}
+
 static const struct dsa_switch_ops mt7530_switch_ops = {
 	.get_tag_protocol	= mtk_get_tag_protocol,
 	.setup			= mt753x_setup,
@@ -2835,6 +2876,8 @@ static const struct dsa_switch_ops mt7530_switch_ops = {
 	.phylink_mac_an_restart	= mt753x_phylink_mac_an_restart,
 	.phylink_mac_link_down	= mt753x_phylink_mac_link_down,
 	.phylink_mac_link_up	= mt753x_phylink_mac_link_up,
+	.get_mac_eee		= mt753x_get_mac_eee,
+	.set_mac_eee		= mt753x_set_mac_eee,
 };
 
 static const struct mt753x_info mt753x_table[] = {
diff --git a/drivers/net/dsa/mt7530.h b/drivers/net/dsa/mt7530.h
index ec36ea5dfd57..0204da486f3a 100644
--- a/drivers/net/dsa/mt7530.h
+++ b/drivers/net/dsa/mt7530.h
@@ -257,6 +257,8 @@ enum mt7530_vlan_port_attr {
 #define  PMCR_RX_EN			BIT(13)
 #define  PMCR_BACKOFF_EN		BIT(9)
 #define  PMCR_BACKPR_EN			BIT(8)
+#define  PMCR_FORCE_EEE1G		BIT(7)
+#define  PMCR_FORCE_EEE100		BIT(6)
 #define  PMCR_TX_FC_EN			BIT(5)
 #define  PMCR_RX_FC_EN			BIT(4)
 #define  PMCR_FORCE_SPEED_1000		BIT(3)
@@ -281,7 +283,8 @@ enum mt7530_vlan_port_attr {
 #define  PMCR_LINK_SETTINGS_MASK	(PMCR_TX_EN | PMCR_FORCE_SPEED_1000 | \
 					 PMCR_RX_EN | PMCR_FORCE_SPEED_100 | \
 					 PMCR_TX_FC_EN | PMCR_RX_FC_EN | \
-					 PMCR_FORCE_FDX | PMCR_FORCE_LNK)
+					 PMCR_FORCE_FDX | PMCR_FORCE_LNK | \
+					 PMCR_FORCE_EEE1G | PMCR_FORCE_EEE100)
 #define  PMCR_CPU_PORT_SETTING(id)	(PMCR_FORCE_MODE_ID((id)) | \
 					 PMCR_IFG_XMIT(1) | PMCR_MAC_MODE | \
 					 PMCR_BACKOFF_EN | PMCR_BACKPR_EN | \
@@ -290,6 +293,15 @@ enum mt7530_vlan_port_attr {
 					 PMCR_FORCE_SPEED_1000 | \
 					 PMCR_FORCE_FDX | PMCR_FORCE_LNK)
 
+#define MT7530_PMEEECR_P(x)		(0x3004 + (x) * 0x100)
+#define  WAKEUP_TIME_1000(x)		(((x) & 0xFF) << 24)
+#define  WAKEUP_TIME_100(x)		(((x) & 0xFF) << 16)
+#define  LPI_THRESH_MASK		GENMASK(15, 4)
+#define  LPI_THRESH_SHT			4
+#define  SET_LPI_THRESH(x)		(((x) << LPI_THRESH_SHT) & LPI_THRESH_MASK)
+#define  GET_LPI_THRESH(x)		(((x) & LPI_THRESH_MASK) >> LPI_THRESH_SHT)
+#define  LPI_MODE_EN			BIT(0)
+
 #define MT7530_PMSR_P(x)		(0x3008 + (x) * 0x100)
 #define  PMSR_EEE1G			BIT(7)
 #define  PMSR_EEE100M			BIT(6)
-- 
2.30.2