Merge branch 'amd-xgbe-add-support-for-2-5gbe-and-rx-adaptation'

Raju Rangoju says:

====================
amd-xgbe: add support for 2.5GbE and rx-adaptation

This patch series adds support for 2.GbE in 10GBaseT mode and
rx-adaptation support for Yellow Carp devices.

1) Support for 2.5GbE:
   Add the necessary changes to the driver to fully recognize and enable
   2.5GbE speed in 10GBaseT mode.

2) Support for rx-adaptation:
   In order to support the 10G backplane mode without Auto-negotiation
   and to support the longer-length DAC cables, it requires PHY to
   perform RX Adaptation sequence as mentioned in the Synopsys databook.
   Add the necessary changes to Yellow Carp devices to ensure seamless
   RX Adaptation for 10G-SFI (LONG DAC), and 10G-KR modes without
   Auto-Negotiation (CL72 not present)
====================

Link: https://lore.kernel.org/r/20230201054932.212700-1-Raju.Rangoju@amd.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

3 files changed, 224 insertions, 6 deletions

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-common.h b/drivers/net/ethernet/amd/xgbe/xgbe-common.h
index 3fd9728f817f..3b70f6737633 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-common.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-common.h
@@ -1285,6 +1285,22 @@
 #define MDIO_PMA_RX_CTRL1		0x8051
 #endif
 
+#ifndef MDIO_PMA_RX_LSTS
+#define MDIO_PMA_RX_LSTS		0x018020
+#endif
+
+#ifndef MDIO_PMA_RX_EQ_CTRL4
+#define MDIO_PMA_RX_EQ_CTRL4		0x0001805C
+#endif
+
+#ifndef MDIO_PMA_MP_MISC_STS
+#define MDIO_PMA_MP_MISC_STS		0x0078
+#endif
+
+#ifndef MDIO_PMA_PHY_RX_EQ_CEU
+#define MDIO_PMA_PHY_RX_EQ_CEU		0x1800E
+#endif
+
 #ifndef MDIO_PCS_DIG_CTRL
 #define MDIO_PCS_DIG_CTRL		0x8000
 #endif
@@ -1395,6 +1411,28 @@
 #define XGBE_PMA_RX_RST_0_RESET_ON	0x10
 #define XGBE_PMA_RX_RST_0_RESET_OFF	0x00
 
+#define XGBE_PMA_RX_SIG_DET_0_MASK	BIT(4)
+#define XGBE_PMA_RX_SIG_DET_0_ENABLE	BIT(4)
+#define XGBE_PMA_RX_SIG_DET_0_DISABLE	0x0000
+
+#define XGBE_PMA_RX_VALID_0_MASK	BIT(12)
+#define XGBE_PMA_RX_VALID_0_ENABLE	BIT(12)
+#define XGBE_PMA_RX_VALID_0_DISABLE	0x0000
+
+#define XGBE_PMA_RX_AD_REQ_MASK		BIT(12)
+#define XGBE_PMA_RX_AD_REQ_ENABLE	BIT(12)
+#define XGBE_PMA_RX_AD_REQ_DISABLE	0x0000
+
+#define XGBE_PMA_RX_ADPT_ACK_MASK	BIT(12)
+#define XGBE_PMA_RX_ADPT_ACK		BIT(12)
+
+#define XGBE_PMA_CFF_UPDTM1_VLD		BIT(8)
+#define XGBE_PMA_CFF_UPDT0_VLD		BIT(9)
+#define XGBE_PMA_CFF_UPDT1_VLD		BIT(10)
+#define XGBE_PMA_CFF_UPDT_MASK		(XGBE_PMA_CFF_UPDTM1_VLD |\
+					 XGBE_PMA_CFF_UPDT0_VLD | \
+					 XGBE_PMA_CFF_UPDT1_VLD)
+
 #define XGBE_PMA_PLL_CTRL_MASK		BIT(15)
 #define XGBE_PMA_PLL_CTRL_ENABLE	BIT(15)
 #define XGBE_PMA_PLL_CTRL_DISABLE	0x0000
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c b/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c
index f4683d53e58c..7d88caa4e623 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c
@@ -388,6 +388,9 @@ struct xgbe_phy_data {
 static DEFINE_MUTEX(xgbe_phy_comm_lock);
 
 static enum xgbe_an_mode xgbe_phy_an_mode(struct xgbe_prv_data *pdata);
+static void xgbe_phy_rrc(struct xgbe_prv_data *pdata);
+static void xgbe_phy_perform_ratechange(struct xgbe_prv_data *pdata,
+					unsigned int cmd, unsigned int sub_cmd);
 
 static int xgbe_phy_i2c_xfer(struct xgbe_prv_data *pdata,
 			     struct xgbe_i2c_op *i2c_op)
@@ -1882,6 +1885,9 @@ static void xgbe_phy_an_advertising(struct xgbe_prv_data *pdata,
 		if (phy_data->phydev &&
 		    (phy_data->phydev->speed == SPEED_10000))
 			XGBE_SET_ADV(dlks, 10000baseKR_Full);
+		else if (phy_data->phydev &&
+			 (phy_data->phydev->speed == SPEED_2500))
+			XGBE_SET_ADV(dlks, 2500baseX_Full);
 		else
 			XGBE_SET_ADV(dlks, 1000baseKX_Full);
 		break;
@@ -2035,6 +2041,93 @@ static void xgbe_phy_set_redrv_mode(struct xgbe_prv_data *pdata)
 	xgbe_phy_put_comm_ownership(pdata);
 }
 
+#define MAX_RX_ADAPT_RETRIES		1
+#define XGBE_PMA_RX_VAL_SIG_MASK	(XGBE_PMA_RX_SIG_DET_0_MASK | \
+					 XGBE_PMA_RX_VALID_0_MASK)
+
+static void xgbe_set_rx_adap_mode(struct xgbe_prv_data *pdata,
+				  enum xgbe_mode mode)
+{
+	if (pdata->rx_adapt_retries++ >= MAX_RX_ADAPT_RETRIES) {
+		pdata->rx_adapt_retries = 0;
+		return;
+	}
+
+	xgbe_phy_perform_ratechange(pdata,
+				    mode == XGBE_MODE_KR ?
+				    XGBE_MB_CMD_SET_10G_KR :
+				    XGBE_MB_CMD_SET_10G_SFI,
+				    XGBE_MB_SUBCMD_RX_ADAP);
+}
+
+static void xgbe_rx_adaptation(struct xgbe_prv_data *pdata)
+{
+	struct xgbe_phy_data *phy_data = pdata->phy_data;
+	unsigned int reg;
+
+	/* step 2: force PCS to send RX_ADAPT Req to PHY */
+	XMDIO_WRITE_BITS(pdata, MDIO_MMD_PMAPMD, MDIO_PMA_RX_EQ_CTRL4,
+			 XGBE_PMA_RX_AD_REQ_MASK, XGBE_PMA_RX_AD_REQ_ENABLE);
+
+	/* Step 3: Wait for RX_ADAPT ACK from the PHY */
+	msleep(200);
+
+	/* Software polls for coefficient update command (given by local PHY) */
+	reg = XMDIO_READ(pdata, MDIO_MMD_PMAPMD, MDIO_PMA_PHY_RX_EQ_CEU);
+
+	/* Clear the RX_AD_REQ bit */
+	XMDIO_WRITE_BITS(pdata, MDIO_MMD_PMAPMD, MDIO_PMA_RX_EQ_CTRL4,
+			 XGBE_PMA_RX_AD_REQ_MASK, XGBE_PMA_RX_AD_REQ_DISABLE);
+
+	/* Check if coefficient update command is set */
+	if ((reg & XGBE_PMA_CFF_UPDT_MASK) != XGBE_PMA_CFF_UPDT_MASK)
+		goto set_mode;
+
+	/* Step 4: Check for Block lock */
+
+	/* Link status is latched low, so read once to clear
+	 * and then read again to get current state
+	 */
+	reg = XMDIO_READ(pdata, MDIO_MMD_PCS, MDIO_STAT1);
+	reg = XMDIO_READ(pdata, MDIO_MMD_PCS, MDIO_STAT1);
+	if (reg & MDIO_STAT1_LSTATUS) {
+		/* If the block lock is found, update the helpers
+		 * and declare the link up
+		 */
+		netif_dbg(pdata, link, pdata->netdev, "Block_lock done");
+		pdata->rx_adapt_done = true;
+		pdata->mode_set = false;
+		return;
+	}
+
+set_mode:
+	xgbe_set_rx_adap_mode(pdata, phy_data->cur_mode);
+}
+
+static void xgbe_phy_rx_adaptation(struct xgbe_prv_data *pdata)
+{
+	unsigned int reg;
+
+rx_adapt_reinit:
+	reg = XMDIO_READ_BITS(pdata, MDIO_MMD_PMAPMD, MDIO_PMA_RX_LSTS,
+			      XGBE_PMA_RX_VAL_SIG_MASK);
+
+	/* step 1: Check for RX_VALID && LF_SIGDET */
+	if ((reg & XGBE_PMA_RX_VAL_SIG_MASK) != XGBE_PMA_RX_VAL_SIG_MASK) {
+		netif_dbg(pdata, link, pdata->netdev,
+			  "RX_VALID or LF_SIGDET is unset, issue rrc");
+		xgbe_phy_rrc(pdata);
+		if (pdata->rx_adapt_retries++ >= MAX_RX_ADAPT_RETRIES) {
+			pdata->rx_adapt_retries = 0;
+			return;
+		}
+		goto rx_adapt_reinit;
+	}
+
+	/* perform rx adaptation */
+	xgbe_rx_adaptation(pdata);
+}
+
 static void xgbe_phy_rx_reset(struct xgbe_prv_data *pdata)
 {
 	int reg;
@@ -2100,7 +2193,7 @@ static void xgbe_phy_perform_ratechange(struct xgbe_prv_data *pdata,
 	wait = XGBE_RATECHANGE_COUNT;
 	while (wait--) {
 		if (!XP_IOREAD_BITS(pdata, XP_DRIVER_INT_RO, STATUS))
-			goto reenable_pll;
+			goto do_rx_adaptation;
 
 		usleep_range(1000, 2000);
 	}
@@ -2110,6 +2203,20 @@ static void xgbe_phy_perform_ratechange(struct xgbe_prv_data *pdata,
 
 	/* Reset on error */
 	xgbe_phy_rx_reset(pdata);
+	goto reenable_pll;
+
+do_rx_adaptation:
+	if (pdata->en_rx_adap && sub_cmd == XGBE_MB_SUBCMD_RX_ADAP &&
+	    (cmd == XGBE_MB_CMD_SET_10G_KR || cmd == XGBE_MB_CMD_SET_10G_SFI)) {
+		netif_dbg(pdata, link, pdata->netdev,
+			  "Enabling RX adaptation\n");
+		pdata->mode_set = true;
+		xgbe_phy_rx_adaptation(pdata);
+		/* return from here to avoid enabling PLL ctrl
+		 * during adaptation phase
+		 */
+		return;
+	}
 
 reenable_pll:
 	/* Enable PLL re-initialization, not needed for PHY Power Off and RRC cmds */
@@ -2138,6 +2245,31 @@ static void xgbe_phy_power_off(struct xgbe_prv_data *pdata)
 	netif_dbg(pdata, link, pdata->netdev, "phy powered off\n");
 }
 
+static bool enable_rx_adap(struct xgbe_prv_data *pdata, enum xgbe_mode mode)
+{
+	struct xgbe_phy_data *phy_data = pdata->phy_data;
+	unsigned int ver;
+
+	/* Rx-Adaptation is not supported on older platforms(< 0x30H) */
+	ver = XGMAC_GET_BITS(pdata->hw_feat.version, MAC_VR, SNPSVER);
+	if (ver < 0x30)
+		return false;
+
+	/* Re-driver models 4223 && 4227 do not support Rx-Adaptation */
+	if (phy_data->redrv &&
+	    (phy_data->redrv_model == XGBE_PHY_REDRV_MODEL_4223 ||
+	     phy_data->redrv_model == XGBE_PHY_REDRV_MODEL_4227))
+		return false;
+
+	/* 10G KR mode with AN does not support Rx-Adaptation */
+	if (mode == XGBE_MODE_KR &&
+	    phy_data->port_mode != XGBE_PORT_MODE_BACKPLANE_NO_AUTONEG)
+		return false;
+
+	pdata->en_rx_adap = 1;
+	return true;
+}
+
 static void xgbe_phy_sfi_mode(struct xgbe_prv_data *pdata)
 {
 	struct xgbe_phy_data *phy_data = pdata->phy_data;
@@ -2146,7 +2278,12 @@ static void xgbe_phy_sfi_mode(struct xgbe_prv_data *pdata)
 
 	/* 10G/SFI */
 	if (phy_data->sfp_cable != XGBE_SFP_CABLE_PASSIVE) {
+		pdata->en_rx_adap = 0;
 		xgbe_phy_perform_ratechange(pdata, XGBE_MB_CMD_SET_10G_SFI, XGBE_MB_SUBCMD_ACTIVE);
+	} else if ((phy_data->sfp_cable == XGBE_SFP_CABLE_PASSIVE) &&
+		   (enable_rx_adap(pdata, XGBE_MODE_SFI))) {
+		xgbe_phy_perform_ratechange(pdata, XGBE_MB_CMD_SET_10G_SFI,
+					    XGBE_MB_SUBCMD_RX_ADAP);
 	} else {
 		if (phy_data->sfp_cable_len <= 1)
 			xgbe_phy_perform_ratechange(pdata, XGBE_MB_CMD_SET_10G_SFI,
@@ -2227,7 +2364,12 @@ static void xgbe_phy_kr_mode(struct xgbe_prv_data *pdata)
 	xgbe_phy_set_redrv_mode(pdata);
 
 	/* 10G/KR */
-	xgbe_phy_perform_ratechange(pdata, XGBE_MB_CMD_SET_10G_KR, XGBE_MB_SUBCMD_NONE);
+	if (enable_rx_adap(pdata, XGBE_MODE_KR))
+		xgbe_phy_perform_ratechange(pdata, XGBE_MB_CMD_SET_10G_KR,
+					    XGBE_MB_SUBCMD_RX_ADAP);
+	else
+		xgbe_phy_perform_ratechange(pdata, XGBE_MB_CMD_SET_10G_KR,
+					    XGBE_MB_SUBCMD_NONE);
 
 	phy_data->cur_mode = XGBE_MODE_KR;
 
@@ -2282,9 +2424,11 @@ static enum xgbe_mode xgbe_phy_switch_baset_mode(struct xgbe_prv_data *pdata)
 	case XGBE_MODE_SGMII_100:
 	case XGBE_MODE_SGMII_1000:
 		return XGBE_MODE_KR;
+	case XGBE_MODE_KX_2500:
+		return XGBE_MODE_SGMII_1000;
 	case XGBE_MODE_KR:
 	default:
-		return XGBE_MODE_SGMII_1000;
+		return XGBE_MODE_KX_2500;
 	}
 }
 
@@ -2644,7 +2788,8 @@ static bool xgbe_phy_valid_speed_baset_mode(struct xgbe_prv_data *pdata,
 	case SPEED_1000:
 		return true;
 	case SPEED_2500:
-		return (phy_data->port_mode == XGBE_PORT_MODE_NBASE_T);
+		return ((phy_data->port_mode == XGBE_PORT_MODE_10GBASE_T) ||
+			(phy_data->port_mode == XGBE_PORT_MODE_NBASE_T));
 	case SPEED_10000:
 		return (phy_data->port_mode == XGBE_PORT_MODE_10GBASE_T);
 	default:
@@ -2737,8 +2882,11 @@ static int xgbe_phy_link_status(struct xgbe_prv_data *pdata, int *an_restart)
 			return 0;
 		}
 
-		if (phy_data->sfp_mod_absent || phy_data->sfp_rx_los)
+		if (phy_data->sfp_mod_absent || phy_data->sfp_rx_los) {
+			if (pdata->en_rx_adap)
+				pdata->rx_adapt_done = false;
 			return 0;
+		}
 	}
 
 	if (phy_data->phydev) {
@@ -2760,7 +2908,29 @@ static int xgbe_phy_link_status(struct xgbe_prv_data *pdata, int *an_restart)
 	 */
 	reg = XMDIO_READ(pdata, MDIO_MMD_PCS, MDIO_STAT1);
 	reg = XMDIO_READ(pdata, MDIO_MMD_PCS, MDIO_STAT1);
-	if (reg & MDIO_STAT1_LSTATUS)
+
+	if (pdata->en_rx_adap) {
+		/* if the link is available and adaptation is done,
+		 * declare link up
+		 */
+		if ((reg & MDIO_STAT1_LSTATUS) && pdata->rx_adapt_done)
+			return 1;
+		/* If either link is not available or adaptation is not done,
+		 * retrigger the adaptation logic. (if the mode is not set,
+		 * then issue mailbox command first)
+		 */
+		if (pdata->mode_set) {
+			xgbe_phy_rx_adaptation(pdata);
+		} else {
+			pdata->rx_adapt_done = false;
+			xgbe_phy_set_mode(pdata, phy_data->cur_mode);
+		}
+
+		/* check again for the link and adaptation status */
+		reg = XMDIO_READ(pdata, MDIO_MMD_PCS, MDIO_STAT1);
+		if ((reg & MDIO_STAT1_LSTATUS) && pdata->rx_adapt_done)
+			return 1;
+	} else if (reg & MDIO_STAT1_LSTATUS)
 		return 1;
 
 	if (pdata->phy.autoneg == AUTONEG_ENABLE &&
@@ -3024,6 +3194,7 @@ static bool xgbe_phy_port_mode_mismatch(struct xgbe_prv_data *pdata)
 		if ((phy_data->port_speeds & XGBE_PHY_PORT_SPEED_10) ||
 		    (phy_data->port_speeds & XGBE_PHY_PORT_SPEED_100) ||
 		    (phy_data->port_speeds & XGBE_PHY_PORT_SPEED_1000) ||
+		    (phy_data->port_speeds & XGBE_PHY_PORT_SPEED_2500) ||
 		    (phy_data->port_speeds & XGBE_PHY_PORT_SPEED_10000))
 			return false;
 		break;
@@ -3474,6 +3645,10 @@ static int xgbe_phy_init(struct xgbe_prv_data *pdata)
 			XGBE_SET_SUP(lks, 1000baseT_Full);
 			phy_data->start_mode = XGBE_MODE_SGMII_1000;
 		}
+		if (phy_data->port_speeds & XGBE_PHY_PORT_SPEED_2500) {
+			XGBE_SET_SUP(lks, 2500baseT_Full);
+			phy_data->start_mode = XGBE_MODE_KX_2500;
+		}
 		if (phy_data->port_speeds & XGBE_PHY_PORT_SPEED_10000) {
 			XGBE_SET_SUP(lks, 10000baseT_Full);
 			phy_data->start_mode = XGBE_MODE_KR;
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe.h b/drivers/net/ethernet/amd/xgbe/xgbe.h
index 16e73df3e9b9..ad136ed493ed 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe.h
@@ -625,6 +625,7 @@ enum xgbe_mb_cmd {
 
 enum xgbe_mb_subcmd {
 	XGBE_MB_SUBCMD_NONE = 0,
+	XGBE_MB_SUBCMD_RX_ADAP,
 
 	/* 10GbE SFP subcommands */
 	XGBE_MB_SUBCMD_ACTIVE = 0,
@@ -1316,6 +1317,10 @@ struct xgbe_prv_data {
 
 	bool debugfs_an_cdr_workaround;
 	bool debugfs_an_cdr_track_early;
+	bool en_rx_adap;
+	int rx_adapt_retries;
+	bool rx_adapt_done;
+	bool mode_set;
 };
 
 /* Function prototypes*/