[PATCH 4/4] net: macb: add support for high speed interface

[Milind Parab <mparab@cadence.com>]

This patch add support for high speed USXGMII PCS and 10G
speed in Cadence ethernet controller driver.

Signed-off-by: Milind Parab <mparab@cadence.com>
---
 drivers/net/ethernet/cadence/macb.h      |   40 +++++++++
 drivers/net/ethernet/cadence/macb_main.c |  130 +++++++++++++++++++++++++++---
 2 files changed, 160 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index 34136a8..d064d76 100644
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -82,6 +82,7 @@
 #define GEM_USRIO		0x000c /* User IO */
 #define GEM_DMACFG		0x0010 /* DMA Configuration */
 #define GEM_JML			0x0048 /* Jumbo Max Length */
+#define GEM_HS_MAC_CONFIG	0x0050 /* GEM high speed config */
 #define GEM_HRB			0x0080 /* Hash Bottom */
 #define GEM_HRT			0x0084 /* Hash Top */
 #define GEM_SA1B		0x0088 /* Specific1 Bottom */
@@ -167,6 +168,9 @@
 #define GEM_DCFG7		0x0298 /* Design Config 7 */
 #define GEM_DCFG8		0x029C /* Design Config 8 */
 #define GEM_DCFG10		0x02A4 /* Design Config 10 */
+#define GEM_DCFG12		0x02AC /* Design Config 12 */
+#define GEM_USX_CONTROL		0x0A80 /* USXGMII control register */
+#define GEM_USX_STATUS		0x0A88 /* USXGMII status register */
 
 #define GEM_TXBDCTRL	0x04cc /* TX Buffer Descriptor control register */
 #define GEM_RXBDCTRL	0x04d0 /* RX Buffer Descriptor control register */
@@ -274,6 +278,8 @@
 #define MACB_IRXFCS_SIZE	1
 
 /* GEM specific NCR bitfields. */
+#define GEM_ENABLE_HS_MAC_OFFSET	31
+#define GEM_ENABLE_HS_MAC_SIZE		1
 #define GEM_TWO_PT_FIVE_GIG_OFFSET	29
 #define GEM_TWO_PT_FIVE_GIG_SIZE	1
 
@@ -465,6 +471,10 @@
 #define MACB_REV_OFFSET				0
 #define MACB_REV_SIZE				16
 
+/* Bitfield in HS_MAC_CONFIG */
+#define GEM_HS_MAC_SPEED_OFFSET			0
+#define GEM_HS_MAC_SPEED_SIZE			3
+
 /* Bitfields in PCS_CONTROL. */
 #define GEM_PCS_CTRL_RST_OFFSET			15
 #define GEM_PCS_CTRL_RST_SIZE			1
@@ -510,6 +520,34 @@
 #define GEM_RXBD_RDBUFF_OFFSET			8
 #define GEM_RXBD_RDBUFF_SIZE			4
 
+/* Bitfields in DCFG12. */
+#define GEM_HIGH_SPEED_OFFSET			26
+#define GEM_HIGH_SPEED_SIZE			1
+
+/* Bitfields in USX_CONTROL. */
+#define GEM_USX_CTRL_SPEED_OFFSET		14
+#define GEM_USX_CTRL_SPEED_SIZE			3
+#define GEM_SERDES_RATE_OFFSET			12
+#define GEM_SERDES_RATE_SIZE			2
+#define GEM_RX_SCR_BYPASS_OFFSET		9
+#define GEM_RX_SCR_BYPASS_SIZE			1
+#define GEM_TX_SCR_BYPASS_OFFSET		8
+#define GEM_TX_SCR_BYPASS_SIZE			1
+#define GEM_RX_SYNC_RESET_OFFSET		2
+#define GEM_RX_SYNC_RESET_SIZE			1
+#define GEM_TX_EN_OFFSET			1
+#define GEM_TX_EN_SIZE				1
+#define GEM_SIGNAL_OK_OFFSET			0
+#define GEM_SIGNAL_OK_SIZE			1
+
+/* Bitfields in USX_STATUS. */
+#define GEM_USX_TX_FAULT_OFFSET			28
+#define GEM_USX_TX_FAULT_SIZE			1
+#define GEM_USX_RX_FAULT_OFFSET			27
+#define GEM_USX_RX_FAULT_SIZE			1
+#define GEM_USX_BLOCK_LOCK_OFFSET		0
+#define GEM_USX_BLOCK_LOCK_SIZE			1
+
 /* Bitfields in TISUBN */
 #define GEM_SUBNSINCR_OFFSET			0
 #define GEM_SUBNSINCRL_OFFSET			24
@@ -673,6 +711,7 @@
 #define MACB_CAPS_SG_DISABLED			BIT(30)
 #define MACB_CAPS_MACB_IS_GEM			BIT(31)
 #define MACB_CAPS_PCS				BIT(24)
+#define MACB_CAPS_HIGH_SPEED			BIT(25)
 
 /* LSO settings */
 #define MACB_LSO_UFO_ENABLE			0x01
@@ -741,6 +780,7 @@
 	})
 
 #define MACB_READ_NSR(bp)	macb_readl(bp, NSR)
+#define GEM_READ_USX_STATUS(bp)	gem_readl(bp, USX_STATUS)
 
 /* struct macb_dma_desc - Hardware DMA descriptor
  * @addr: DMA address of data buffer
diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index fe107f0..a4c197f 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -81,6 +81,18 @@ struct sifive_fu540_macb_mgmt {
 #define MACB_WOL_HAS_MAGIC_PACKET	(0x1 << 0)
 #define MACB_WOL_ENABLED		(0x1 << 1)
 
+enum {
+	HS_MAC_SPEED_100M,
+	HS_MAC_SPEED_1000M,
+	HS_MAC_SPEED_2500M,
+	HS_MAC_SPEED_5000M,
+	HS_MAC_SPEED_10000M,
+};
+
+enum {
+	MACB_SERDES_RATE_10G = 1,
+};
+
 /* Graceful stop timeouts in us. We should allow up to
  * 1 frame time (10 Mbits/s, full-duplex, ignoring collisions)
  */
@@ -90,6 +102,8 @@ struct sifive_fu540_macb_mgmt {
 
 #define MACB_MDIO_TIMEOUT	1000000 /* in usecs */
 
+#define MACB_USX_BLOCK_LOCK_TIMEOUT	1000000 /* in usecs */
+
 /* DMA buffer descriptor might be different size
  * depends on hardware configuration:
  *
@@ -489,12 +503,32 @@ static void gem_phylink_validate(struct phylink_config *pl_config,
 		if (!macb_is_gem(bp))
 			goto empty_set;
 		break;
+	case PHY_INTERFACE_MODE_USXGMII:
+		if (!(bp->caps & MACB_CAPS_HIGH_SPEED &&
+		      bp->caps & MACB_CAPS_PCS))
+			goto empty_set;
+		break;
 	default:
 		break;
 	}
 
 	switch (state->interface) {
 	case PHY_INTERFACE_MODE_NA:
+	case PHY_INTERFACE_MODE_USXGMII:
+	case PHY_INTERFACE_MODE_10GKR:
+		if (bp->caps & MACB_CAPS_GIGABIT_MODE_AVAILABLE) {
+			phylink_set(mask, 10000baseCR_Full);
+			phylink_set(mask, 10000baseER_Full);
+			phylink_set(mask, 10000baseKR_Full);
+			phylink_set(mask, 10000baseLR_Full);
+			phylink_set(mask, 10000baseLRM_Full);
+			phylink_set(mask, 10000baseSR_Full);
+			phylink_set(mask, 10000baseT_Full);
+			phylink_set(mask, 5000baseT_Full);
+			phylink_set(mask, 2500baseX_Full);
+			phylink_set(mask, 1000baseX_Full);
+		}
+	/* fallthrough */
 	case PHY_INTERFACE_MODE_SGMII:
 	case PHY_INTERFACE_MODE_GMII:
 	case PHY_INTERFACE_MODE_RGMII:
@@ -530,6 +564,80 @@ static int gem_phylink_mac_link_state(struct phylink_config *pl_config,
 	return -EOPNOTSUPP;
 }
 
+static int macb_wait_for_usx_block_lock(struct macb *bp)
+{
+	u32 val;
+
+	return readx_poll_timeout(GEM_READ_USX_STATUS, bp, val,
+				  val & GEM_BIT(USX_BLOCK_LOCK),
+				  1, MACB_USX_BLOCK_LOCK_TIMEOUT);
+}
+
+static inline int gem_mac_usx_configure(struct macb *bp, int spd)
+{
+	u32 speed, config;
+
+	gem_writel(bp, NCFGR, GEM_BIT(PCSSEL) |
+		   (~GEM_BIT(SGMIIEN) & gem_readl(bp, NCFGR)));
+	gem_writel(bp, NCR, gem_readl(bp, NCR) |
+		   GEM_BIT(ENABLE_HS_MAC));
+	gem_writel(bp, NCFGR, gem_readl(bp, NCFGR) |
+		   MACB_BIT(FD));
+	config = gem_readl(bp, USX_CONTROL);
+	config = GEM_BFINS(SERDES_RATE, MACB_SERDES_RATE_10G, config);
+	config &= ~GEM_BIT(TX_SCR_BYPASS);
+	config &= ~GEM_BIT(RX_SCR_BYPASS);
+	gem_writel(bp, USX_CONTROL, config |
+		   GEM_BIT(TX_EN));
+	config = gem_readl(bp, USX_CONTROL);
+	gem_writel(bp, USX_CONTROL, config | GEM_BIT(SIGNAL_OK));
+	if (macb_wait_for_usx_block_lock(bp) < 0) {
+		netdev_warn(bp->dev, "USXGMII block lock failed");
+		return -ETIMEDOUT;
+	}
+
+	switch (spd) {
+	case SPEED_10000:
+		speed = HS_MAC_SPEED_10000M;
+		break;
+	case SPEED_5000:
+		speed = HS_MAC_SPEED_5000M;
+		break;
+	case SPEED_2500:
+		speed = HS_MAC_SPEED_2500M;
+		break;
+	case SPEED_1000:
+		speed = HS_MAC_SPEED_1000M;
+		break;
+	default:
+	case SPEED_100:
+		speed = HS_MAC_SPEED_100M;
+		break;
+	}
+
+	gem_writel(bp, HS_MAC_CONFIG, GEM_BFINS(HS_MAC_SPEED, speed,
+						gem_readl(bp, HS_MAC_CONFIG)));
+	gem_writel(bp, USX_CONTROL, GEM_BFINS(USX_CTRL_SPEED, speed,
+					      gem_readl(bp, USX_CONTROL)));
+	return 0;
+}
+
+static inline void gem_mac_configure(struct macb *bp, int speed)
+{
+	switch (speed) {
+	case SPEED_1000:
+		gem_writel(bp, NCFGR, GEM_BIT(GBE) |
+			   gem_readl(bp, NCFGR));
+		break;
+	case SPEED_100:
+		macb_writel(bp, NCFGR, MACB_BIT(SPD) |
+			    macb_readl(bp, NCFGR));
+		break;
+	default:
+		break;
+	}
+}
+
 static void gem_mac_config(struct phylink_config *pl_config, unsigned int mode,
 			   const struct phylink_link_state *state)
 {
@@ -572,18 +680,17 @@ static void gem_mac_config(struct phylink_config *pl_config, unsigned int mode,
 			reg &= ~GEM_BIT(GBE);
 		if (state->duplex)
 			reg |= MACB_BIT(FD);
+		macb_or_gem_writel(bp, NCFGR, reg);
 
-		switch (state->speed) {
-		case SPEED_1000:
-			reg |= GEM_BIT(GBE);
-			break;
-		case SPEED_100:
-			reg |= MACB_BIT(SPD);
-			break;
-		default:
-			break;
+		if (bp->phy_interface == PHY_INTERFACE_MODE_USXGMII) {
+			if (gem_mac_usx_configure(bp, state->speed) < 0) {
+				spin_unlock_irqrestore(&bp->lock, flags);
+				phylink_mac_change(bp->pl, false);
+				return;
+			}
+		} else {
+			gem_mac_configure(bp, state->speed);
 		}
-		macb_or_gem_writel(bp, NCFGR, reg);
 
 		bp->speed = state->speed;
 		bp->duplex = state->duplex;
@@ -3419,6 +3526,9 @@ static void macb_configure_caps(struct macb *bp,
 			bp->caps |= MACB_CAPS_ISR_CLEAR_ON_WRITE;
 		if (GEM_BFEXT(NO_PCS, dcfg) == 0)
 			bp->caps |= MACB_CAPS_PCS;
+		dcfg = gem_readl(bp, DCFG12);
+		if (GEM_BFEXT(HIGH_SPEED, dcfg) == 1)
+			bp->caps |= MACB_CAPS_HIGH_SPEED;
 		dcfg = gem_readl(bp, DCFG2);
 		if ((dcfg & (GEM_BIT(RX_PKT_BUFF) | GEM_BIT(TX_PKT_BUFF))) == 0)
 			bp->caps |= MACB_CAPS_FIFO_MODE;
-- 
1.7.1