net: ethernet: add driver for Aurora VLSI NB8800 Ethernet controller

This adds a driver for the Aurora VLSI NB8800 Ethernet controller.
It is an almost complete rewrite of a driver originally found in
a Sigma Designs 2.6.22 tree.
Signed-off-by: NMans Rullgard <mans@mansr.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/Kconfig

@@ -29,6 +29,7 @@ source "drivers/net/ethernet/apm/Kconfig"
 source "drivers/net/ethernet/apple/Kconfig"
 source "drivers/net/ethernet/arc/Kconfig"
 source "drivers/net/ethernet/atheros/Kconfig"
+source "drivers/net/ethernet/aurora/Kconfig"
 source "drivers/net/ethernet/cadence/Kconfig"
 source "drivers/net/ethernet/adi/Kconfig"
 source "drivers/net/ethernet/broadcom/Kconfig"

drivers/net/ethernet/Makefile

@@ -15,6 +15,7 @@ obj-$(CONFIG_NET_XGENE) += apm/
 obj-$(CONFIG_NET_VENDOR_APPLE) += apple/
 obj-$(CONFIG_NET_VENDOR_ARC) += arc/
 obj-$(CONFIG_NET_VENDOR_ATHEROS) += atheros/
+obj-$(CONFIG_NET_VENDOR_AURORA) += aurora/
 obj-$(CONFIG_NET_CADENCE) += cadence/
 obj-$(CONFIG_NET_BFIN) += adi/
 obj-$(CONFIG_NET_VENDOR_BROADCOM) += broadcom/

drivers/net/ethernet/aurora/Kconfig

+config NET_VENDOR_AURORA
+	bool "Aurora VLSI devices"
+	help
+	  If you have a network (Ethernet) device belonging to this class,
+	  say Y.
+
+	  Note that the answer to this question doesn't directly affect the
+	  kernel: saying N will just cause the configurator to skip all
+	  questions about Aurora devices. If you say Y, you will be asked
+	  for your specific device in the following questions.
+
+if NET_VENDOR_AURORA
+
+config AURORA_NB8800
+	tristate "Aurora AU-NB8800 support"
+	select PHYLIB
+	help
+	 Support for the AU-NB8800 gigabit Ethernet controller.
+
+endif

drivers/net/ethernet/aurora/Makefile

+obj-$(CONFIG_AURORA_NB8800) += nb8800.o

drivers/net/ethernet/aurora/nb8800.h

+#ifndef _NB8800_H_
+#define _NB8800_H_
+
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <linux/phy.h>
+#include <linux/clk.h>
+#include <linux/bitops.h>
+
+#define RX_DESC_COUNT			256
+#define TX_DESC_COUNT			256
+
+#define NB8800_DESC_LOW			4
+
+#define RX_BUF_SIZE			1552
+
+#define RX_COPYBREAK			256
+#define RX_COPYHDR			128
+
+#define MAX_MDC_CLOCK			2500000
+
+/* Stargate Solutions SSN8800 core registers */
+#define NB8800_TX_CTL1			0x000
+#define TX_TPD				BIT(5)
+#define TX_APPEND_FCS			BIT(4)
+#define TX_PAD_EN			BIT(3)
+#define TX_RETRY_EN			BIT(2)
+#define TX_EN				BIT(0)
+
+#define NB8800_TX_CTL2			0x001
+
+#define NB8800_RX_CTL			0x004
+#define RX_BC_DISABLE			BIT(7)
+#define RX_RUNT				BIT(6)
+#define RX_AF_EN			BIT(5)
+#define RX_PAUSE_EN			BIT(3)
+#define RX_SEND_CRC			BIT(2)
+#define RX_PAD_STRIP			BIT(1)
+#define RX_EN				BIT(0)
+
+#define NB8800_RANDOM_SEED		0x008
+#define NB8800_TX_SDP			0x14
+#define NB8800_TX_TPDP1			0x18
+#define NB8800_TX_TPDP2			0x19
+#define NB8800_SLOT_TIME		0x1c
+
+#define NB8800_MDIO_CMD			0x020
+#define MDIO_CMD_GO			BIT(31)
+#define MDIO_CMD_WR			BIT(26)
+#define MDIO_CMD_ADDR(x)		((x) << 21)
+#define MDIO_CMD_REG(x)			((x) << 16)
+#define MDIO_CMD_DATA(x)		((x) <<	 0)
+
+#define NB8800_MDIO_STS			0x024
+#define MDIO_STS_ERR			BIT(31)
+
+#define NB8800_MC_ADDR(i)		(0x028 + (i))
+#define NB8800_MC_INIT			0x02e
+#define NB8800_UC_ADDR(i)		(0x03c + (i))
+
+#define NB8800_MAC_MODE			0x044
+#define RGMII_MODE			BIT(7)
+#define HALF_DUPLEX			BIT(4)
+#define BURST_EN			BIT(3)
+#define LOOPBACK_EN			BIT(2)
+#define GMAC_MODE			BIT(0)
+
+#define NB8800_IC_THRESHOLD		0x050
+#define NB8800_PE_THRESHOLD		0x051
+#define NB8800_PF_THRESHOLD		0x052
+#define NB8800_TX_BUFSIZE		0x054
+#define NB8800_FIFO_CTL			0x056
+#define NB8800_PQ1			0x060
+#define NB8800_PQ2			0x061
+#define NB8800_SRC_ADDR(i)		(0x06a + (i))
+#define NB8800_STAT_DATA		0x078
+#define NB8800_STAT_INDEX		0x07c
+#define NB8800_STAT_CLEAR		0x07d
+
+#define NB8800_SLEEP_MODE		0x07e
+#define SLEEP_MODE			BIT(0)
+
+#define NB8800_WAKEUP			0x07f
+#define WAKEUP				BIT(0)
+
+/* Aurora NB8800 host interface registers */
+#define NB8800_TXC_CR			0x100
+#define TCR_LK				BIT(12)
+#define TCR_DS				BIT(11)
+#define TCR_BTS(x)			(((x) & 0x7) << 8)
+#define TCR_DIE				BIT(7)
+#define TCR_TFI(x)			(((x) & 0x7) << 4)
+#define TCR_LE				BIT(3)
+#define TCR_RS				BIT(2)
+#define TCR_DM				BIT(1)
+#define TCR_EN				BIT(0)
+
+#define NB8800_TXC_SR			0x104
+#define TSR_DE				BIT(3)
+#define TSR_DI				BIT(2)
+#define TSR_TO				BIT(1)
+#define TSR_TI				BIT(0)
+
+#define NB8800_TX_SAR			0x108
+#define NB8800_TX_DESC_ADDR		0x10c
+
+#define NB8800_TX_REPORT_ADDR		0x110
+#define TX_BYTES_TRANSFERRED(x)		(((x) >> 16) & 0xffff)
+#define TX_FIRST_DEFERRAL		BIT(7)
+#define TX_EARLY_COLLISIONS(x)		(((x) >> 3) & 0xf)
+#define TX_LATE_COLLISION		BIT(2)
+#define TX_PACKET_DROPPED		BIT(1)
+#define TX_FIFO_UNDERRUN		BIT(0)
+#define IS_TX_ERROR(r)			((r) & 0x07)
+
+#define NB8800_TX_FIFO_SR		0x114
+#define NB8800_TX_ITR			0x118
+
+#define NB8800_RXC_CR			0x200
+#define RCR_FL				BIT(13)
+#define RCR_LK				BIT(12)
+#define RCR_DS				BIT(11)
+#define RCR_BTS(x)			(((x) & 7) << 8)
+#define RCR_DIE				BIT(7)
+#define RCR_RFI(x)			(((x) & 7) << 4)
+#define RCR_LE				BIT(3)
+#define RCR_RS				BIT(2)
+#define RCR_DM				BIT(1)
+#define RCR_EN				BIT(0)
+
+#define NB8800_RXC_SR			0x204
+#define RSR_DE				BIT(3)
+#define RSR_DI				BIT(2)
+#define RSR_RO				BIT(1)
+#define RSR_RI				BIT(0)
+
+#define NB8800_RX_SAR			0x208
+#define NB8800_RX_DESC_ADDR		0x20c
+
+#define NB8800_RX_REPORT_ADDR		0x210
+#define RX_BYTES_TRANSFERRED(x)		(((x) >> 16) & 0xFFFF)
+#define RX_MULTICAST_PKT		BIT(9)
+#define RX_BROADCAST_PKT		BIT(8)
+#define RX_LENGTH_ERR			BIT(7)
+#define RX_FCS_ERR			BIT(6)
+#define RX_RUNT_PKT			BIT(5)
+#define RX_FIFO_OVERRUN			BIT(4)
+#define RX_LATE_COLLISION		BIT(3)
+#define RX_ALIGNMENT_ERROR		BIT(2)
+#define RX_ERROR_MASK			0xfc
+#define IS_RX_ERROR(r)			((r) & RX_ERROR_MASK)
+
+#define NB8800_RX_FIFO_SR		0x214
+#define NB8800_RX_ITR			0x218
+
+/* Sigma Designs SMP86xx additional registers */
+#define NB8800_TANGOX_PAD_MODE		0x400
+#define PAD_MODE_MASK			0x7
+#define PAD_MODE_MII			0x0
+#define PAD_MODE_RGMII			0x1
+#define PAD_MODE_GTX_CLK_INV		BIT(3)
+#define PAD_MODE_GTX_CLK_DELAY		BIT(4)
+
+#define NB8800_TANGOX_MDIO_CLKDIV	0x420
+#define NB8800_TANGOX_RESET		0x424
+
+/* Hardware DMA descriptor */
+struct nb8800_dma_desc {
+	u32				s_addr;	/* start address */
+	u32				n_addr;	/* next descriptor address */
+	u32				r_addr;	/* report address */
+	u32				config;
+} __aligned(8);
+
+#define DESC_ID				BIT(23)
+#define DESC_EOC			BIT(22)
+#define DESC_EOF			BIT(21)
+#define DESC_LK				BIT(20)
+#define DESC_DS				BIT(19)
+#define DESC_BTS(x)			(((x) & 0x7) << 16)
+
+/* DMA descriptor and associated data for rx.
+ * Allocated from coherent memory.
+ */
+struct nb8800_rx_desc {
+	/* DMA descriptor */
+	struct nb8800_dma_desc		desc;
+
+	/* Status report filled in by hardware */
+	u32				report;
+};
+
+/* Address of buffer on rx ring */
+struct nb8800_rx_buf {
+	struct page			*page;
+	unsigned long			offset;
+};
+
+/* DMA descriptors and associated data for tx.
+ * Allocated from coherent memory.
+ */
+struct nb8800_tx_desc {
+	/* DMA descriptor.  The second descriptor is used if packet
+	 * data is unaligned.
+	 */
+	struct nb8800_dma_desc		desc[2];
+
+	/* Status report filled in by hardware */
+	u32				report;
+
+	/* Bounce buffer for initial unaligned part of packet */
+	u8				buf[8] __aligned(8);
+};
+
+/* Packet in tx queue */
+struct nb8800_tx_buf {
+	/* Currently queued skb */
+	struct sk_buff			*skb;
+
+	/* DMA address of the first descriptor */
+	dma_addr_t			dma_desc;
+
+	/* DMA address of packet data */
+	dma_addr_t			dma_addr;
+
+	/* Length of DMA mapping, less than skb->len if alignment
+	 * buffer is used.
+	 */
+	unsigned int			dma_len;
+
+	/* Number of packets in chain starting here */
+	unsigned int			chain_len;
+
+	/* Packet chain ready to be submitted to hardware */
+	bool				ready;
+};
+
+struct nb8800_priv {
+	struct napi_struct		napi;
+
+	void __iomem			*base;
+
+	/* RX DMA descriptors */
+	struct nb8800_rx_desc		*rx_descs;
+
+	/* RX buffers referenced by DMA descriptors */
+	struct nb8800_rx_buf		*rx_bufs;
+
+	/* Current end of chain */
+	u32				rx_eoc;
+
+	/* Value for rx interrupt time register in NAPI interrupt mode */
+	u32				rx_itr_irq;
+
+	/* Value for rx interrupt time register in NAPI poll mode */
+	u32				rx_itr_poll;
+
+	/* Value for config field of rx DMA descriptors */
+	u32				rx_dma_config;
+
+	/* TX DMA descriptors */
+	struct nb8800_tx_desc		*tx_descs;
+
+	/* TX packet queue */
+	struct nb8800_tx_buf		*tx_bufs;
+
+	/* Number of free tx queue entries */
+	atomic_t			tx_free;
+
+	/* First free tx queue entry */
+	u32				tx_next;
+
+	/* Next buffer to transmit */
+	u32				tx_queue;
+
+	/* Start of current packet chain */
+	struct nb8800_tx_buf		*tx_chain;
+
+	/* Next buffer to reclaim */
+	u32				tx_done;
+
+	/* Lock for DMA activation */
+	spinlock_t			tx_lock;
+
+	struct mii_bus			*mii_bus;
+	struct device_node		*phy_node;
+	struct phy_device		*phydev;
+
+	/* PHY connection type from DT */
+	int				phy_mode;
+
+	/* Current link status */
+	int				speed;
+	int				duplex;
+	int				link;
+
+	/* Pause settings */
+	bool				pause_aneg;
+	bool				pause_rx;
+	bool				pause_tx;
+
+	/* DMA base address of rx descriptors, see rx_descs above */
+	dma_addr_t			rx_desc_dma;
+
+	/* DMA base address of tx descriptors, see tx_descs above */
+	dma_addr_t			tx_desc_dma;
+
+	struct clk			*clk;
+};
+
+struct nb8800_ops {
+	int				(*init)(struct net_device *dev);
+	int				(*reset)(struct net_device *dev);
+};
+
+#endif /* _NB8800_H_ */