/*
   * Copyright 2010-2011 Calxeda, Inc.
   *
   * SPDX-License-Identifier:	GPL-2.0+
   */
  
  #include <common.h>
  #include <malloc.h>
  #include <linux/compiler.h>
  #include <linux/err.h>
  #include <asm/io.h>
  
  #define TX_NUM_DESC			1
  #define RX_NUM_DESC			32
  
  #define MAC_TIMEOUT			(5*CONFIG_SYS_HZ)
  
  #define ETH_BUF_SZ			2048
  #define TX_BUF_SZ			(ETH_BUF_SZ * TX_NUM_DESC)
  #define RX_BUF_SZ			(ETH_BUF_SZ * RX_NUM_DESC)
  
  #define RXSTART				0x00000002
  #define TXSTART				0x00002000
  
  #define RXENABLE			0x00000004
  #define TXENABLE			0x00000008
  
  #define XGMAC_CONTROL_SPD		0x40000000
  #define XGMAC_CONTROL_SPD_MASK		0x60000000
  #define XGMAC_CONTROL_SARC		0x10000000
  #define XGMAC_CONTROL_SARK_MASK		0x18000000
  #define XGMAC_CONTROL_CAR		0x04000000
  #define XGMAC_CONTROL_CAR_MASK		0x06000000
  #define XGMAC_CONTROL_CAR_SHIFT		25
  #define XGMAC_CONTROL_DP		0x01000000
  #define XGMAC_CONTROL_WD		0x00800000
  #define XGMAC_CONTROL_JD		0x00400000
  #define XGMAC_CONTROL_JE		0x00100000
  #define XGMAC_CONTROL_LM		0x00001000
  #define XGMAC_CONTROL_IPC		0x00000400
  #define XGMAC_CONTROL_ACS		0x00000080
  #define XGMAC_CONTROL_DDIC		0x00000010
  #define XGMAC_CONTROL_TE		0x00000008
  #define XGMAC_CONTROL_RE		0x00000004
  
  #define XGMAC_DMA_BUSMODE_RESET		0x00000001
  #define XGMAC_DMA_BUSMODE_DSL		0x00000004
  #define XGMAC_DMA_BUSMODE_DSL_MASK	0x0000007c
  #define XGMAC_DMA_BUSMODE_DSL_SHIFT	2
  #define XGMAC_DMA_BUSMODE_ATDS		0x00000080
  #define XGMAC_DMA_BUSMODE_PBL_MASK	0x00003f00
  #define XGMAC_DMA_BUSMODE_PBL_SHIFT	8
  #define XGMAC_DMA_BUSMODE_FB		0x00010000
  #define XGMAC_DMA_BUSMODE_USP		0x00800000
  #define XGMAC_DMA_BUSMODE_8PBL		0x01000000
  #define XGMAC_DMA_BUSMODE_AAL		0x02000000
  
  #define XGMAC_DMA_AXIMODE_ENLPI		0x80000000
  #define XGMAC_DMA_AXIMODE_MGK		0x40000000
  #define XGMAC_DMA_AXIMODE_WROSR		0x00100000
  #define XGMAC_DMA_AXIMODE_WROSR_MASK	0x00F00000
  #define XGMAC_DMA_AXIMODE_WROSR_SHIFT	20
  #define XGMAC_DMA_AXIMODE_RDOSR		0x00010000
  #define XGMAC_DMA_AXIMODE_RDOSR_MASK	0x000F0000
  #define XGMAC_DMA_AXIMODE_RDOSR_SHIFT	16
  #define XGMAC_DMA_AXIMODE_AAL		0x00001000
  #define XGMAC_DMA_AXIMODE_BLEN256	0x00000080
  #define XGMAC_DMA_AXIMODE_BLEN128	0x00000040
  #define XGMAC_DMA_AXIMODE_BLEN64	0x00000020
  #define XGMAC_DMA_AXIMODE_BLEN32	0x00000010
  #define XGMAC_DMA_AXIMODE_BLEN16	0x00000008
  #define XGMAC_DMA_AXIMODE_BLEN8		0x00000004
  #define XGMAC_DMA_AXIMODE_BLEN4		0x00000002
  #define XGMAC_DMA_AXIMODE_UNDEF		0x00000001
  
  #define XGMAC_CORE_OMR_RTC_SHIFT	3
  #define XGMAC_CORE_OMR_RTC_MASK		0x00000018
  #define XGMAC_CORE_OMR_RTC		0x00000010
  #define XGMAC_CORE_OMR_RSF		0x00000020
  #define XGMAC_CORE_OMR_DT		0x00000040
  #define XGMAC_CORE_OMR_FEF		0x00000080
  #define XGMAC_CORE_OMR_EFC		0x00000100
  #define XGMAC_CORE_OMR_RFA_SHIFT	9
  #define XGMAC_CORE_OMR_RFA_MASK		0x00000E00
  #define XGMAC_CORE_OMR_RFD_SHIFT	12
  #define XGMAC_CORE_OMR_RFD_MASK		0x00007000
  #define XGMAC_CORE_OMR_TTC_SHIFT	16
  #define XGMAC_CORE_OMR_TTC_MASK		0x00030000
  #define XGMAC_CORE_OMR_TTC		0x00020000
  #define XGMAC_CORE_OMR_FTF		0x00100000
  #define XGMAC_CORE_OMR_TSF		0x00200000
  
  #define FIFO_MINUS_1K			0x0
  #define FIFO_MINUS_2K			0x1
  #define FIFO_MINUS_3K			0x2
  #define FIFO_MINUS_4K			0x3
  #define FIFO_MINUS_6K			0x4
  #define FIFO_MINUS_8K			0x5
  #define FIFO_MINUS_12K			0x6
  #define FIFO_MINUS_16K			0x7
  
  #define XGMAC_CORE_FLOW_PT_SHIFT	16
  #define XGMAC_CORE_FLOW_PT_MASK		0xFFFF0000
  #define XGMAC_CORE_FLOW_PT		0x00010000
  #define XGMAC_CORE_FLOW_DZQP		0x00000080
  #define XGMAC_CORE_FLOW_PLT_SHIFT	4
  #define XGMAC_CORE_FLOW_PLT_MASK	0x00000030
  #define XGMAC_CORE_FLOW_PLT		0x00000010
  #define XGMAC_CORE_FLOW_UP		0x00000008
  #define XGMAC_CORE_FLOW_RFE		0x00000004
  #define XGMAC_CORE_FLOW_TFE		0x00000002
  #define XGMAC_CORE_FLOW_FCB		0x00000001
  
  /* XGMAC Descriptor Defines */
  #define MAX_DESC_BUF_SZ			(0x2000 - 8)
  
  #define RXDESC_EXT_STATUS		0x00000001
  #define RXDESC_CRC_ERR			0x00000002
  #define RXDESC_RX_ERR			0x00000008
  #define RXDESC_RX_WDOG			0x00000010
  #define RXDESC_FRAME_TYPE		0x00000020
  #define RXDESC_GIANT_FRAME		0x00000080
  #define RXDESC_LAST_SEG			0x00000100
  #define RXDESC_FIRST_SEG		0x00000200
  #define RXDESC_VLAN_FRAME		0x00000400
  #define RXDESC_OVERFLOW_ERR		0x00000800
  #define RXDESC_LENGTH_ERR		0x00001000
  #define RXDESC_SA_FILTER_FAIL		0x00002000
  #define RXDESC_DESCRIPTOR_ERR		0x00004000
  #define RXDESC_ERROR_SUMMARY		0x00008000
  #define RXDESC_FRAME_LEN_OFFSET		16
  #define RXDESC_FRAME_LEN_MASK		0x3fff0000
  #define RXDESC_DA_FILTER_FAIL		0x40000000
  
  #define RXDESC1_END_RING		0x00008000
  
  #define RXDESC_IP_PAYLOAD_MASK		0x00000003
  #define RXDESC_IP_PAYLOAD_UDP		0x00000001
  #define RXDESC_IP_PAYLOAD_TCP		0x00000002
  #define RXDESC_IP_PAYLOAD_ICMP		0x00000003
  #define RXDESC_IP_HEADER_ERR		0x00000008
  #define RXDESC_IP_PAYLOAD_ERR		0x00000010
  #define RXDESC_IPV4_PACKET		0x00000040
  #define RXDESC_IPV6_PACKET		0x00000080
  #define TXDESC_UNDERFLOW_ERR		0x00000001
  #define TXDESC_JABBER_TIMEOUT		0x00000002
  #define TXDESC_LOCAL_FAULT		0x00000004
  #define TXDESC_REMOTE_FAULT		0x00000008
  #define TXDESC_VLAN_FRAME		0x00000010
  #define TXDESC_FRAME_FLUSHED		0x00000020
  #define TXDESC_IP_HEADER_ERR		0x00000040
  #define TXDESC_PAYLOAD_CSUM_ERR		0x00000080
  #define TXDESC_ERROR_SUMMARY		0x00008000
  #define TXDESC_SA_CTRL_INSERT		0x00040000
  #define TXDESC_SA_CTRL_REPLACE		0x00080000
  #define TXDESC_2ND_ADDR_CHAINED		0x00100000
  #define TXDESC_END_RING			0x00200000
  #define TXDESC_CSUM_IP			0x00400000
  #define TXDESC_CSUM_IP_PAYLD		0x00800000
  #define TXDESC_CSUM_ALL			0x00C00000
  #define TXDESC_CRC_EN_REPLACE		0x01000000
  #define TXDESC_CRC_EN_APPEND		0x02000000
  #define TXDESC_DISABLE_PAD		0x04000000
  #define TXDESC_FIRST_SEG		0x10000000
  #define TXDESC_LAST_SEG			0x20000000
  #define TXDESC_INTERRUPT		0x40000000
  
  #define DESC_OWN			0x80000000
  #define DESC_BUFFER1_SZ_MASK		0x00001fff
  #define DESC_BUFFER2_SZ_MASK		0x1fff0000
  #define DESC_BUFFER2_SZ_OFFSET		16
  
  struct xgmac_regs {
  	u32 config;
  	u32 framefilter;
  	u32 resv_1[4];
  	u32 flow_control;
  	u32 vlantag;
  	u32 version;
  	u32 vlaninclude;
  	u32 resv_2[2];
  	u32 pacestretch;
  	u32 vlanhash;
  	u32 resv_3;
  	u32 intreg;
  	struct {
  		u32 hi;         /* 0x40 */
  		u32 lo;         /* 0x44 */
  	} macaddr[16];
  	u32 resv_4[0xd0];
  	u32 core_opmode;	/* 0x400 */
  	u32 resv_5[0x2bf];
  	u32 busmode;		/* 0xf00 */
  	u32 txpoll;
  	u32 rxpoll;
  	u32 rxdesclist;
  	u32 txdesclist;
  	u32 dma_status;
  	u32 dma_opmode;
  	u32 intenable;
  	u32 resv_6[2];
  	u32 axi_mode;		/* 0xf28 */
  };
  
  struct xgmac_dma_desc {
  	__le32 flags;
  	__le32 buf_size;
  	__le32 buf1_addr;		/* Buffer 1 Address Pointer */
  	__le32 buf2_addr;		/* Buffer 2 Address Pointer */
  	__le32 ext_status;
  	__le32 res[3];
  };
  
  /* XGMAC Descriptor Access Helpers */
  static inline void desc_set_buf_len(struct xgmac_dma_desc *p, u32 buf_sz)
  {
  	if (buf_sz > MAX_DESC_BUF_SZ)
  		p->buf_size = cpu_to_le32(MAX_DESC_BUF_SZ |
  			(buf_sz - MAX_DESC_BUF_SZ) << DESC_BUFFER2_SZ_OFFSET);
  	else
  		p->buf_size = cpu_to_le32(buf_sz);
  }
  
  static inline int desc_get_buf_len(struct xgmac_dma_desc *p)
  {
  	u32 len = le32_to_cpu(p->buf_size);
  	return (len & DESC_BUFFER1_SZ_MASK) +
  		((len & DESC_BUFFER2_SZ_MASK) >> DESC_BUFFER2_SZ_OFFSET);
  }
  
  static inline void desc_init_rx_desc(struct xgmac_dma_desc *p, int ring_size,
  				     int buf_sz)
  {
  	struct xgmac_dma_desc *end = p + ring_size - 1;
  
  	memset(p, 0, sizeof(*p) * ring_size);
  
  	for (; p <= end; p++)
  		desc_set_buf_len(p, buf_sz);
  
  	end->buf_size |= cpu_to_le32(RXDESC1_END_RING);
  }
  
  static inline void desc_init_tx_desc(struct xgmac_dma_desc *p, u32 ring_size)
  {
  	memset(p, 0, sizeof(*p) * ring_size);
  	p[ring_size - 1].flags = cpu_to_le32(TXDESC_END_RING);
  }
  
  static inline int desc_get_owner(struct xgmac_dma_desc *p)
  {
  	return le32_to_cpu(p->flags) & DESC_OWN;
  }
  
  static inline void desc_set_rx_owner(struct xgmac_dma_desc *p)
  {
  	/* Clear all fields and set the owner */
  	p->flags = cpu_to_le32(DESC_OWN);
  }
  
  static inline void desc_set_tx_owner(struct xgmac_dma_desc *p, u32 flags)
  {
  	u32 tmpflags = le32_to_cpu(p->flags);
  	tmpflags &= TXDESC_END_RING;
  	tmpflags |= flags | DESC_OWN;
  	p->flags = cpu_to_le32(tmpflags);
  }
  
  static inline void *desc_get_buf_addr(struct xgmac_dma_desc *p)
  {
  	return (void *)le32_to_cpu(p->buf1_addr);
  }
  
  static inline void desc_set_buf_addr(struct xgmac_dma_desc *p,
  				     void *paddr, int len)
  {
  	p->buf1_addr = cpu_to_le32(paddr);
  	if (len > MAX_DESC_BUF_SZ)
  		p->buf2_addr = cpu_to_le32(paddr + MAX_DESC_BUF_SZ);
  }
  
  static inline void desc_set_buf_addr_and_size(struct xgmac_dma_desc *p,
  					      void *paddr, int len)
  {
  	desc_set_buf_len(p, len);
  	desc_set_buf_addr(p, paddr, len);
  }
  
  static inline int desc_get_rx_frame_len(struct xgmac_dma_desc *p)
  {
  	u32 data = le32_to_cpu(p->flags);
  	u32 len = (data & RXDESC_FRAME_LEN_MASK) >> RXDESC_FRAME_LEN_OFFSET;
  	if (data & RXDESC_FRAME_TYPE)
  		len -= 4;
  
  	return len;
  }
  
  struct calxeda_eth_dev {
  	struct xgmac_dma_desc rx_chain[RX_NUM_DESC];
  	struct xgmac_dma_desc tx_chain[TX_NUM_DESC];
  	char rxbuffer[RX_BUF_SZ];
  
  	u32 tx_currdesc;
  	u32 rx_currdesc;
  
  	struct eth_device *dev;
  } __aligned(32);
  
  /*
   * Initialize a descriptor ring.  Calxeda XGMAC is configured to use
   * advanced descriptors.
   */
  
  static void init_rx_desc(struct calxeda_eth_dev *priv)
  {
  	struct xgmac_dma_desc *rxdesc = priv->rx_chain;
  	struct xgmac_regs *regs = (struct xgmac_regs *)priv->dev->iobase;
  	void *rxbuffer = priv->rxbuffer;
  	int i;
  
  	desc_init_rx_desc(rxdesc, RX_NUM_DESC, ETH_BUF_SZ);
  	writel((ulong)rxdesc, &regs->rxdesclist);
  
  	for (i = 0; i < RX_NUM_DESC; i++) {
  		desc_set_buf_addr(rxdesc + i, rxbuffer + (i * ETH_BUF_SZ),
  				  ETH_BUF_SZ);
  		desc_set_rx_owner(rxdesc + i);
  	}
  }
  
  static void init_tx_desc(struct calxeda_eth_dev *priv)
  {
  	struct xgmac_regs *regs = (struct xgmac_regs *)priv->dev->iobase;
  
  	desc_init_tx_desc(priv->tx_chain, TX_NUM_DESC);
  	writel((ulong)priv->tx_chain, &regs->txdesclist);
  }
  
  static int xgmac_reset(struct eth_device *dev)
  {
  	struct xgmac_regs *regs = (struct xgmac_regs *)dev->iobase;
  	int timeout = MAC_TIMEOUT;
  	u32 value;
  
  	value = readl(&regs->config) & XGMAC_CONTROL_SPD_MASK;
  
  	writel(XGMAC_DMA_BUSMODE_RESET, &regs->busmode);
  	while ((timeout-- >= 0) &&
  		(readl(&regs->busmode) & XGMAC_DMA_BUSMODE_RESET))
  		udelay(1);
  
  	writel(value, &regs->config);
  
  	return timeout;
  }
  
  static void xgmac_hwmacaddr(struct eth_device *dev)
  {
  	struct xgmac_regs *regs = (struct xgmac_regs *)dev->iobase;
  	u32 macaddr[2];
  
  	memcpy(macaddr, dev->enetaddr, 6);
  	writel(macaddr[1], &regs->macaddr[0].hi);
  	writel(macaddr[0], &regs->macaddr[0].lo);
  }
  
  static int xgmac_init(struct eth_device *dev, bd_t * bis)
  {
  	struct xgmac_regs *regs = (struct xgmac_regs *)dev->iobase;
  	struct calxeda_eth_dev *priv = dev->priv;
  	int value;
  
  	if (xgmac_reset(dev) < 0)
  		return -1;
  
  	/* set the hardware MAC address */
  	xgmac_hwmacaddr(dev);
  
  	/* set the AXI bus modes */
  	value = XGMAC_DMA_BUSMODE_ATDS |
  		(16 << XGMAC_DMA_BUSMODE_PBL_SHIFT) |
  		XGMAC_DMA_BUSMODE_FB | XGMAC_DMA_BUSMODE_AAL;
  	writel(value, &regs->busmode);
  
  	value = XGMAC_DMA_AXIMODE_AAL | XGMAC_DMA_AXIMODE_BLEN16 |
  		XGMAC_DMA_AXIMODE_BLEN8 | XGMAC_DMA_AXIMODE_BLEN4;
  	writel(value, &regs->axi_mode);
  
  	/* set flow control parameters and store and forward mode */
  	value = (FIFO_MINUS_12K << XGMAC_CORE_OMR_RFD_SHIFT) |
  		(FIFO_MINUS_4K << XGMAC_CORE_OMR_RFA_SHIFT) |
  		XGMAC_CORE_OMR_EFC | XGMAC_CORE_OMR_TSF;
  	writel(value, &regs->core_opmode);
  
  	/* enable pause frames */
  	value = (1024 << XGMAC_CORE_FLOW_PT_SHIFT) |
  		(1 << XGMAC_CORE_FLOW_PLT_SHIFT) |
  		XGMAC_CORE_FLOW_UP | XGMAC_CORE_FLOW_RFE | XGMAC_CORE_FLOW_TFE;
  	writel(value, &regs->flow_control);
  
  	/* Initialize the descriptor chains */
  	init_rx_desc(priv);
  	init_tx_desc(priv);
  
  	/* must set to 0, or when started up will cause issues */
  	priv->tx_currdesc = 0;
  	priv->rx_currdesc = 0;
  
  	/* set default core values */
  	value = readl(&regs->config);
  	value &= XGMAC_CONTROL_SPD_MASK;
  	value |= XGMAC_CONTROL_DDIC | XGMAC_CONTROL_ACS |
  		XGMAC_CONTROL_IPC | XGMAC_CONTROL_CAR;
  
  	/* Everything is ready enable both mac and DMA */
  	value |= RXENABLE | TXENABLE;
  	writel(value, &regs->config);
  
  	value = readl(&regs->dma_opmode);
  	value |= RXSTART | TXSTART;
  	writel(value, &regs->dma_opmode);
  
  	return 0;
  }
  
  static int xgmac_tx(struct eth_device *dev, void *packet, int length)
  {
  	struct xgmac_regs *regs = (struct xgmac_regs *)dev->iobase;
  	struct calxeda_eth_dev *priv = dev->priv;
  	u32 currdesc = priv->tx_currdesc;
  	struct xgmac_dma_desc *txdesc = &priv->tx_chain[currdesc];
  	int timeout;
  
  	desc_set_buf_addr_and_size(txdesc, packet, length);
  	desc_set_tx_owner(txdesc, TXDESC_FIRST_SEG |
  		TXDESC_LAST_SEG | TXDESC_CRC_EN_APPEND);
  
  	/* write poll demand */
  	writel(1, &regs->txpoll);
  
  	timeout = 1000000;
  	while (desc_get_owner(txdesc)) {
  		if (timeout-- < 0) {
  			printf("xgmac: TX timeout
  ");
  			return -ETIMEDOUT;
  		}
  		udelay(1);
  	}
  
  	priv->tx_currdesc = (currdesc + 1) & (TX_NUM_DESC - 1);
  	return 0;
  }
  
  static int xgmac_rx(struct eth_device *dev)
  {
  	struct xgmac_regs *regs = (struct xgmac_regs *)dev->iobase;
  	struct calxeda_eth_dev *priv = dev->priv;
  	u32 currdesc = priv->rx_currdesc;
  	struct xgmac_dma_desc *rxdesc = &priv->rx_chain[currdesc];
  	int length = 0;
  
  	/* check if the host has the desc */
  	if (desc_get_owner(rxdesc))
  		return -1; /* something bad happened */
  
  	length = desc_get_rx_frame_len(rxdesc);
  
  	NetReceive(desc_get_buf_addr(rxdesc), length);
  
  	/* set descriptor back to owned by XGMAC */
  	desc_set_rx_owner(rxdesc);
  	writel(1, &regs->rxpoll);
  
  	priv->rx_currdesc = (currdesc + 1) & (RX_NUM_DESC - 1);
  
  	return length;
  }
  
  static void xgmac_halt(struct eth_device *dev)
  {
  	struct xgmac_regs *regs = (struct xgmac_regs *)dev->iobase;
  	struct calxeda_eth_dev *priv = dev->priv;
  	int value;
  
  	/* Disable TX/RX */
  	value = readl(&regs->config);
  	value &= ~(RXENABLE | TXENABLE);
  	writel(value, &regs->config);
  
  	/* Disable DMA */
  	value = readl(&regs->dma_opmode);
  	value &= ~(RXSTART | TXSTART);
  	writel(value, &regs->dma_opmode);
  
  	/* must set to 0, or when started up will cause issues */
  	priv->tx_currdesc = 0;
  	priv->rx_currdesc = 0;
  }
  
  int calxedaxgmac_initialize(u32 id, ulong base_addr)
  {
  	struct eth_device *dev;
  	struct calxeda_eth_dev *priv;
  	struct xgmac_regs *regs;
  	u32 macaddr[2];
  
  	regs = (struct xgmac_regs *)base_addr;
  
  	/* check hardware version */
  	if (readl(&regs->version) != 0x1012)
  		return -1;
  
  	dev = malloc(sizeof(*dev));
  	if (!dev)
  		return 0;
  	memset(dev, 0, sizeof(*dev));
  
  	/* Structure must be aligned, because it contains the descriptors */
  	priv = memalign(32, sizeof(*priv));
  	if (!priv) {
  		free(dev);
  		return 0;
  	}
  
  	dev->iobase = (int)base_addr;
  	dev->priv = priv;
  	priv->dev = dev;
  	sprintf(dev->name, "xgmac%d", id);
  
  	/* The MAC address is already configured, so read it from registers. */
  	macaddr[1] = readl(&regs->macaddr[0].hi);
  	macaddr[0] = readl(&regs->macaddr[0].lo);
  	memcpy(dev->enetaddr, macaddr, 6);
  
  	dev->init = xgmac_init;
  	dev->send = xgmac_tx;
  	dev->recv = xgmac_rx;
  	dev->halt = xgmac_halt;
  
  	eth_register(dev);
  
  	return 1;
  }