net: macb: Add support for Xilinx Zynq SoC

Although Xilinx Zynq SoC was using MACB similar hardware. However,
U-boot MACB driver was not supporting Xilinx Zynq SoC. This patch is
to add support for the Xilinx Zynq SoC to the existing MACB network
driver.

This patch is to add Zynq GEM DMA Config, provide callback
function for different linkspeed for case of using Xilinx Zynq
Programmable Logic as GMII to RGMII converter.

This patch convert the return value to use error codes.

Signed-off-by: Wilson Lee <wilson.lee@ni.com>
Cc: Chen Yee Chew <chen.yee.chew@ni.com>
Cc: Keng Soon Cheah <keng.soon.cheah@ni.com>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>

drivers/net/Kconfig

@@ -185,6 +185,13 @@ config MACB
 	  GEM (Gigabit Ethernet MAC) found in some ARM SoC devices.
 	  Say Y to include support for the MACB/GEM chip.
 
+config MACB_ZYNQ
+	bool "Cadence MACB/GEM Ethernet Interface for Xilinx Zynq"
+	depends on MACB
+	help
+	  The Cadence MACB ethernet interface was used on Zynq platform.
+	  Say Y to enable support for the MACB/GEM in Zynq chip.
+
 config PCH_GBE
 	bool "Intel Platform Controller Hub EG20T GMAC driver"
 	depends on DM_ETH && DM_PCI

drivers/net/macb.c

@@ -52,6 +52,22 @@ DECLARE_GLOBAL_DATA_PTR;
 #define MACB_TX_TIMEOUT		1000
 #define MACB_AUTONEG_TIMEOUT	5000000
 
+#ifdef CONFIG_MACB_ZYNQ
+/* INCR4 AHB bursts */
+#define MACB_ZYNQ_GEM_DMACR_BLENGTH		0x00000004
+/* Use full configured addressable space (8 Kb) */
+#define MACB_ZYNQ_GEM_DMACR_RXSIZE		0x00000300
+/* Use full configured addressable space (4 Kb) */
+#define MACB_ZYNQ_GEM_DMACR_TXSIZE		0x00000400
+/* Set RXBUF with use of 128 byte */
+#define MACB_ZYNQ_GEM_DMACR_RXBUF		0x00020000
+#define MACB_ZYNQ_GEM_DMACR_INIT \
+				(MACB_ZYNQ_GEM_DMACR_BLENGTH | \
+				MACB_ZYNQ_GEM_DMACR_RXSIZE | \
+				MACB_ZYNQ_GEM_DMACR_TXSIZE | \
+				MACB_ZYNQ_GEM_DMACR_RXBUF)
+#endif
+
 struct macb_dma_desc {
 	u32	addr;
 	u32	ctrl;
@@ -461,13 +477,25 @@ static int macb_phy_find(struct macb_device *macb, const char *name)
 		phy_id = macb_mdio_read(macb, MII_PHYSID1);
 		if (phy_id != 0xffff) {
 			printf("%s: PHY present at %d\n", name, i);
-			return 1;
+			return 0;
 		}
 	}
 
 	/* PHY isn't up to snuff */
 	printf("%s: PHY not found\n", name);
 
+	return -ENODEV;
+}
+
+/**
+ * macb_linkspd_cb - Linkspeed change callback function
+ * @regs:	Base Register of MACB devices
+ * @speed:	Linkspeed
+ * Returns 0 when operation success and negative errno number
+ * when operation failed.
+ */
+int __weak macb_linkspd_cb(void *regs, unsigned int speed)
+{
 	return 0;
 }
 
@@ -483,18 +511,20 @@ static int macb_phy_init(struct macb_device *macb, const char *name)
 	u32 ncfgr;
 	u16 phy_id, status, adv, lpa;
 	int media, speed, duplex;
+	int ret;
 	int i;
 
 	arch_get_mdio_control(name);
 	/* Auto-detect phy_addr */
-	if (!macb_phy_find(macb, name))
-		return 0;
+	ret = macb_phy_find(macb, name);
+	if (ret)
+		return ret;
 
 	/* Check if the PHY is up to snuff... */
 	phy_id = macb_mdio_read(macb, MII_PHYSID1);
 	if (phy_id == 0xffff) {
 		printf("%s: No PHY present\n", name);
-		return 0;
+		return -ENODEV;
 	}
 
 #ifdef CONFIG_PHYLIB
@@ -530,7 +560,7 @@ static int macb_phy_init(struct macb_device *macb, const char *name)
 	if (!(status & BMSR_LSTATUS)) {
 		printf("%s: link down (status: 0x%04x)\n",
 		       name, status);
-		return 0;
+		return -ENETDOWN;
 	}
 
 	/* First check for GMAC and that it is GiB capable */
@@ -554,7 +584,11 @@ static int macb_phy_init(struct macb_device *macb, const char *name)
 
 			macb_writel(macb, NCFGR, ncfgr);
 
-			return 1;
+			ret = macb_linkspd_cb(macb->regs, _1000BASET);
+			if (ret)
+				return ret;
+
+			return 0;
 		}
 	}
 
@@ -573,13 +607,21 @@ static int macb_phy_init(struct macb_device *macb, const char *name)
 
 	ncfgr = macb_readl(macb, NCFGR);
 	ncfgr &= ~(MACB_BIT(SPD) | MACB_BIT(FD) | GEM_BIT(GBE));
-	if (speed)
+	if (speed) {
 		ncfgr |= MACB_BIT(SPD);
+		ret = macb_linkspd_cb(macb->regs, _100BASET);
+	} else {
+		ret = macb_linkspd_cb(macb->regs, _10BASET);
+	}
+
+	if (ret)
+		return ret;
+
 	if (duplex)
 		ncfgr |= MACB_BIT(FD);
 	macb_writel(macb, NCFGR, ncfgr);
 
-	return 1;
+	return 0;
 }
 
 static int gmac_init_multi_queues(struct macb_device *macb)
@@ -616,6 +658,7 @@ static int _macb_init(struct macb_device *macb, const char *name)
 	struct macb_device *macb = dev_get_priv(dev);
 #endif
 	unsigned long paddr;
+	int ret;
 	int i;
 
 	/*
@@ -649,6 +692,10 @@ static int _macb_init(struct macb_device *macb, const char *name)
 	macb->tx_tail = 0;
 	macb->next_rx_tail = 0;
 
+#ifdef CONFIG_MACB_ZYNQ
+	macb_writel(macb, DMACFG, MACB_ZYNQ_GEM_DMACR_INIT);
+#endif
+
 	macb_writel(macb, RBQP, macb->rx_ring_dma);
 	macb_writel(macb, TBQP, macb->tx_ring_dma);
 
@@ -709,11 +756,12 @@ static int _macb_init(struct macb_device *macb, const char *name)
 	}
 
 #ifdef CONFIG_DM_ETH
-	if (!macb_phy_init(dev, name))
+	ret = macb_phy_init(dev, name);
 #else
-	if (!macb_phy_init(macb, name))
+	ret = macb_phy_init(macb, name);
 #endif
-		return -1;
+	if (ret)
+		return ret;
 
 	/* Enable TX and RX */
 	macb_writel(macb, NCR, MACB_BIT(TE) | MACB_BIT(RE));
@@ -1013,9 +1061,15 @@ static int macb_enable_clk(struct udevice *dev)
 	if (ret)
 		return -EINVAL;
 
+	/*
+	 * Zynq clock driver didn't support for enable or disable
+	 * clock. Hence, clk_enable() didn't apply for Zynq
+	 */
+#ifndef CONFIG_MACB_ZYNQ
 	ret = clk_enable(&clk);
 	if (ret)
 		return ret;
+#endif
 
 	clk_rate = clk_get_rate(&clk);
 	if (!clk_rate)
@@ -1083,12 +1137,24 @@ static int macb_eth_remove(struct udevice *dev)
 	return 0;
 }
 
+/**
+ * macb_late_eth_ofdata_to_platdata
+ * @dev:	udevice struct
+ * Returns 0 when operation success and negative errno number
+ * when operation failed.
+ */
+int __weak macb_late_eth_ofdata_to_platdata(struct udevice *dev)
+{
+	return 0;
+}
+
 static int macb_eth_ofdata_to_platdata(struct udevice *dev)
 {
 	struct eth_pdata *pdata = dev_get_platdata(dev);
 
 	pdata->iobase = devfdt_get_addr(dev);
-	return 0;
+
+	return macb_late_eth_ofdata_to_platdata(dev);
 }
 
 static const struct udevice_id macb_eth_ids[] = {
@@ -1097,6 +1163,7 @@ static const struct udevice_id macb_eth_ids[] = {
 	{ .compatible = "atmel,sama5d2-gem" },
 	{ .compatible = "atmel,sama5d3-gem" },
 	{ .compatible = "atmel,sama5d4-gem" },
+	{ .compatible = "cdns,zynq-gem" },
 	{ }
 };
 

drivers/net/macb.h

@@ -11,6 +11,7 @@
 #define MACB_NCFGR				0x0004
 #define MACB_NSR				0x0008
 #define GEM_UR					0x000c
+#define MACB_DMACFG				0x0010
 #define MACB_TSR				0x0014
 #define MACB_RBQP				0x0018
 #define MACB_TBQP				0x001c