path: root/drivers/net/ethernet/sgi/ioc3-eth.c

// SPDX-License-Identifier: GPL-2.0
/* Driver for SGI's IOC3 based Ethernet cards as found in the PCI card.
 *
 * Copyright (C) 1999, 2000, 01, 03, 06 Ralf Baechle
 * Copyright (C) 1995, 1999, 2000, 2001 by Silicon Graphics, Inc.
 *
 * References:
 *  o IOC3 ASIC specification 4.51, 1996-04-18
 *  o IEEE 802.3 specification, 2000 edition
 *  o DP38840A Specification, National Semiconductor, March 1997
 *
 * To do:
 *
 *  o Use prefetching for large packets.  What is a good lower limit for
 *    prefetching?
 *  o Use hardware checksums.
 *  o Which PHYs might possibly be attached to the IOC3 in real live,
 *    which workarounds are required for them?  Do we ever have Lucent's?
 *  o For the 2.5 branch kill the mii-tool ioctls.
 */

#define IOC3_NAME	"ioc3-eth"
#define IOC3_VERSION	"2.6.3-4"

#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/crc16.h>
#include <linux/crc32.h>
#include <linux/mii.h>
#include <linux/in.h>
#include <linux/io.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/gfp.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/skbuff.h>
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>
#include <linux/nvmem-consumer.h>

#include <net/ip.h>

#include <asm/sn/ioc3.h>
#include <asm/pci/bridge.h>

#define CRC16_INIT	0
#define CRC16_VALID	0xb001

/* Number of RX buffers.  This is tunable in the range of 16 <= x < 512.
 * The value must be a power of two.
 */
#define RX_BUFFS		64
#define RX_RING_ENTRIES		512		/* fixed in hardware */
#define RX_RING_MASK		(RX_RING_ENTRIES - 1)
#define RX_RING_SIZE		(RX_RING_ENTRIES * sizeof(u64))

/* 128 TX buffers (not tunable) */
#define TX_RING_ENTRIES		128
#define TX_RING_MASK		(TX_RING_ENTRIES - 1)
#define TX_RING_SIZE		(TX_RING_ENTRIES * sizeof(struct ioc3_etxd))

/* IOC3 does dma transfers in 128 byte blocks */
#define IOC3_DMA_XFER_LEN	128UL

/* Every RX buffer starts with 8 byte descriptor data */
#define RX_OFFSET		(sizeof(struct ioc3_erxbuf) + NET_IP_ALIGN)
#define RX_BUF_SIZE		(13 * IOC3_DMA_XFER_LEN)

#define ETCSR_FD   ((21 << ETCSR_IPGR2_SHIFT) | (21 << ETCSR_IPGR1_SHIFT) | 21)
#define ETCSR_HD   ((17 << ETCSR_IPGR2_SHIFT) | (11 << ETCSR_IPGR1_SHIFT) | 21)

/* Private per NIC data of the driver.  */
struct ioc3_private {
	struct ioc3_ethregs *regs;
	struct device *dma_dev;
	u32 *ssram;
	unsigned long *rxr;		/* pointer to receiver ring */
	void *tx_ring;
	struct ioc3_etxd *txr;
	dma_addr_t rxr_dma;
	dma_addr_t txr_dma;
	struct sk_buff *rx_skbs[RX_RING_ENTRIES];
	struct sk_buff *tx_skbs[TX_RING_ENTRIES];
	int rx_ci;			/* RX consumer index */
	int rx_pi;			/* RX producer index */
	int tx_ci;			/* TX consumer index */
	int tx_pi;			/* TX producer index */
	int txqlen;
	u32 emcr, ehar_h, ehar_l;
	spinlock_t ioc3_lock;
	struct mii_if_info mii;

	/* Members used by autonegotiation  */
	struct timer_list ioc3_timer;
};

static int ioc3_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
static void ioc3_set_multicast_list(struct net_device *dev);
static netdev_tx_t ioc3_start_xmit(struct sk_buff *skb, struct net_device *dev);
static void ioc3_timeout(struct net_device *dev, unsigned int txqueue);
static inline unsigned int ioc3_hash(const unsigned char *addr);
static void ioc3_start(struct ioc3_private *ip);
static inline void ioc3_stop(struct ioc3_private *ip);
static void ioc3_init(struct net_device *dev);
static int ioc3_alloc_rx_bufs(struct net_device *dev);
static void ioc3_free_rx_bufs(struct ioc3_private *ip);
static inline void ioc3_clean_tx_ring(struct ioc3_private *ip);

static const struct e