path: root/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Combined Ethernet driver for Motorola MPC8xx and MPC82xx.
 *
 * Copyright (c) 2003 Intracom S.A.
 *  by Pantelis Antoniou <panto@intracom.gr>
 *
 * 2005 (c) MontaVista Software, Inc.
 * Vitaly Bordug <vbordug@ru.mvista.com>
 *
 * Heavily based on original FEC driver by Dan Malek <dan@embeddededge.com>
 * and modifications by Joakim Tjernlund <joakim.tjernlund@lumentis.se>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/ethtool.h>
#include <linux/bitops.h>
#include <linux/fs.h>
#include <linux/platform_device.h>
#include <linux/phy.h>
#include <linux/phylink.h>
#include <linux/property.h>
#include <linux/of.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include <linux/pgtable.h>
#include <linux/rtnetlink.h>

#include <linux/vmalloc.h>
#include <asm/irq.h>
#include <linux/uaccess.h>

#include "fs_enet.h"

/*************************************************/

MODULE_AUTHOR("Pantelis Antoniou <panto@intracom.gr>");
MODULE_DESCRIPTION("Freescale Ethernet Driver");
MODULE_LICENSE("GPL");

static int fs_enet_debug = -1; /* -1 == use FS_ENET_DEF_MSG_ENABLE as value */
module_param(fs_enet_debug, int, 0);
MODULE_PARM_DESC(fs_enet_debug,
		 "Freescale bitmapped debugging message enable value");

#define RX_RING_SIZE	32
#define TX_RING_SIZE	64

#ifdef CONFIG_NET_POLL_CONTROLLER
static void fs_enet_netpoll(struct net_device *dev);
#endif

static void fs_set_multicast_list(struct net_device *dev)
{
	struct fs_enet_private *fep = netdev_priv(dev);

	(*fep->ops->set_multicast_list)(dev);
}

static int fs_eth_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
	struct fs_enet_private *fep = netdev_priv(dev);

	return phylink_mii_ioctl(fep->phylink, ifr, cmd);
}

static void skb_align(struct sk_buff *skb, int align)
{
	int off = ((unsigned long)skb->data) & (align - 1);

	if (off)
		skb_reserve(skb, align - off);
}

/* NAPI function */
static int fs_enet_napi(struct napi_struct *napi, int budget)
{
	struct fs_enet_private *fep = container_of(napi, struct fs_enet_private, napi);
	const struct fs_platform_info *fpi = fep->fpi;
	struct net_device *dev = fep->ndev;
	int curidx, dirtyidx, received = 0;
	int do_wake = 0, do_restart = 0;
	int tx_left = TX_RING_SIZE;
	struct sk_buff *skb, *skbn;
	cbd_t __iomem *bdp;
	u16 pkt_len, sc;

	spin_lock(&fep->tx_lock);
	bdp = fep->dirty_tx;

	/* clear status bits for napi*/
	(*fep->ops->napi_clear_event)(dev);

	while (((sc = CBDR_SC(bdp)) & BD_ENET_TX_READY) == 0 && tx_left) {
		dirtyidx = bdp - fep->tx_bd_base;

		if (fep->tx_free == fep->tx_ring)
			break;

		skb = fep->tx_skbuff[dirtyidx];

		 /* Check for errors. */
		if (sc & (BD_ENET_TX_HB | BD_ENET_TX_LC |
			  BD_ENET_TX_RL | BD_ENET_TX_UN | BD_ENET_TX_CSL)) {
			if (sc & BD_ENET_TX_HB)	/* No heartbeat */
				dev->stats.tx_heartbeat_errors++;
			if (sc & BD_ENET_TX_LC)	/* Late collision */
				dev->stats.tx_window_errors++;
			if (sc & BD_ENET_TX_RL)	/* Retrans limit */
				dev->stats.tx_aborted_errors++;
			if (sc & BD_ENET_TX_UN)	/* Underrun */
				dev->stats.tx_fifo_errors++;
			if (sc & BD_ENET_TX_CSL)	/* Carrier lost */
				dev->stats.tx_carrier_errors++;

			if (sc & (BD_ENET_TX_LC | BD_ENET_TX_RL | BD_ENET_TX_UN)) {
				dev->stats.tx_errors++;
				do_restart = 1;
			}
		} else {
			dev->stats.tx_packets++;
		}

		if (sc & BD_ENET_TX_READY) {
			dev_warn(fep->dev,
				 "HEY! Enet xmit interrupt and TX_READY.\n");
		}

		/* Deferred means some collisions occurred during transmit,
		 * but we eventually sent the packet OK.
		 */
		if (sc & BD_ENET_TX_DEF)
			dev->stats.collisions++;

		/* unmap */
		if (fep->mapped_as_page[dirtyidx])
			dma_unmap_page(fep->dev, CBDR_BUFADDR(bdp),
				       CBDR_DATLEN(bdp), DMA_TO_DEVICE);
		else
			dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
					 CBDR_DATLEN(bdp), DMA_TO_DEVICE);

		/* Free the sk buffer associated with this last transmit. */
		if (skb) {
			dev_kfree_skb(skb);
			fep->tx_skbuff[dirtyidx] = NULL;
		}

		/* Update pointer to next buffer descriptor to be transmitted.
		 */
		if ((sc & BD_ENET_TX_WRAP) == 0)
			bdp++;
		else
			bdp = fep->tx_bd_base;

		/* Since we have freed up a buffer, the ring is no longer full.
		 */
		if (++fep