/
greth.c
executable file
·1635 lines (1298 loc) · 39.7 KB
/
greth.c
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/*
* Aeroflex Gaisler GRETH 10/100/1G Ethernet MAC.
*
* 2005-2010 (c) Aeroflex Gaisler AB
*
* This driver supports GRETH 10/100 and GRETH 10/100/1G Ethernet MACs
* available in the GRLIB VHDL IP core library.
*
* Full documentation of both cores can be found here:
* http://www.gaisler.com/products/grlib/grip.pdf
*
* The Gigabit version supports scatter/gather DMA, any alignment of
* buffers and checksum offloading.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* Contributors: Kristoffer Glembo
* Daniel Hellstrom
* Marko Isomaki
*/
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/skbuff.h>
#include <linux/io.h>
#include <linux/crc32.h>
#include <linux/mii.h>
#include <linux/of_device.h>
#include <linux/of_platform.h>
#include <linux/slab.h>
#include <asm/cacheflush.h>
#include <asm/byteorder.h>
#ifdef CONFIG_SPARC
#include <asm/idprom.h>
#endif
#include "greth.h"
#define GRETH_DEF_MSG_ENABLE \
(NETIF_MSG_DRV | \
NETIF_MSG_PROBE | \
NETIF_MSG_LINK | \
NETIF_MSG_IFDOWN | \
NETIF_MSG_IFUP | \
NETIF_MSG_RX_ERR | \
NETIF_MSG_TX_ERR)
static int greth_debug = -1; /* -1 == use GRETH_DEF_MSG_ENABLE as value */
module_param(greth_debug, int, 0);
MODULE_PARM_DESC(greth_debug, "GRETH bitmapped debugging message enable value");
/* Accept MAC address of the form macaddr=0x08,0x00,0x20,0x30,0x40,0x50 */
static int macaddr[6];
module_param_array(macaddr, int, NULL, 0);
MODULE_PARM_DESC(macaddr, "GRETH Ethernet MAC address");
static int greth_edcl = 1;
module_param(greth_edcl, int, 0);
MODULE_PARM_DESC(greth_edcl, "GRETH EDCL usage indicator. Set to 1 if EDCL is used.");
static int greth_open(struct net_device *dev);
static netdev_tx_t greth_start_xmit(struct sk_buff *skb,
struct net_device *dev);
static netdev_tx_t greth_start_xmit_gbit(struct sk_buff *skb,
struct net_device *dev);
static int greth_rx(struct net_device *dev, int limit);
static int greth_rx_gbit(struct net_device *dev, int limit);
static void greth_clean_tx(struct net_device *dev);
static void greth_clean_tx_gbit(struct net_device *dev);
static irqreturn_t greth_interrupt(int irq, void *dev_id);
static int greth_close(struct net_device *dev);
static int greth_set_mac_add(struct net_device *dev, void *p);
static void greth_set_multicast_list(struct net_device *dev);
#define GRETH_REGLOAD(a) (be32_to_cpu(__raw_readl(&(a))))
#define GRETH_REGSAVE(a, v) (__raw_writel(cpu_to_be32(v), &(a)))
#define GRETH_REGORIN(a, v) (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) | (v))))
#define GRETH_REGANDIN(a, v) (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) & (v))))
#define NEXT_TX(N) (((N) + 1) & GRETH_TXBD_NUM_MASK)
#define SKIP_TX(N, C) (((N) + C) & GRETH_TXBD_NUM_MASK)
#define NEXT_RX(N) (((N) + 1) & GRETH_RXBD_NUM_MASK)
static void greth_print_rx_packet(void *addr, int len)
{
print_hex_dump(KERN_DEBUG, "RX: ", DUMP_PREFIX_OFFSET, 16, 1,
addr, len, true);
}
static void greth_print_tx_packet(struct sk_buff *skb)
{
int i;
int length;
if (skb_shinfo(skb)->nr_frags == 0)
length = skb->len;
else
length = skb_headlen(skb);
print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
skb->data, length, true);
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
phys_to_virt(page_to_phys(skb_shinfo(skb)->frags[i].page)) +
skb_shinfo(skb)->frags[i].page_offset,
length, true);
}
}
static inline void greth_enable_tx(struct greth_private *greth)
{
wmb();
GRETH_REGORIN(greth->regs->control, GRETH_TXEN);
}
static inline void greth_disable_tx(struct greth_private *greth)
{
GRETH_REGANDIN(greth->regs->control, ~GRETH_TXEN);
}
static inline void greth_enable_rx(struct greth_private *greth)
{
wmb();
GRETH_REGORIN(greth->regs->control, GRETH_RXEN);
}
static inline void greth_disable_rx(struct greth_private *greth)
{
GRETH_REGANDIN(greth->regs->control, ~GRETH_RXEN);
}
static inline void greth_enable_irqs(struct greth_private *greth)
{
GRETH_REGORIN(greth->regs->control, GRETH_RXI | GRETH_TXI);
}
static inline void greth_disable_irqs(struct greth_private *greth)
{
GRETH_REGANDIN(greth->regs->control, ~(GRETH_RXI|GRETH_TXI));
}
static inline void greth_write_bd(u32 *bd, u32 val)
{
__raw_writel(cpu_to_be32(val), bd);
}
static inline u32 greth_read_bd(u32 *bd)
{
return be32_to_cpu(__raw_readl(bd));
}
static void greth_clean_rings(struct greth_private *greth)
{
int i;
struct greth_bd *rx_bdp = greth->rx_bd_base;
struct greth_bd *tx_bdp = greth->tx_bd_base;
if (greth->gbit_mac) {
/* Free and unmap RX buffers */
for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
if (greth->rx_skbuff[i] != NULL) {
dev_kfree_skb(greth->rx_skbuff[i]);
dma_unmap_single(greth->dev,
greth_read_bd(&rx_bdp->addr),
MAX_FRAME_SIZE+NET_IP_ALIGN,
DMA_FROM_DEVICE);
}
}
/* TX buffers */
while (greth->tx_free < GRETH_TXBD_NUM) {
struct sk_buff *skb = greth->tx_skbuff[greth->tx_last];
int nr_frags = skb_shinfo(skb)->nr_frags;
tx_bdp = greth->tx_bd_base + greth->tx_last;
greth->tx_last = NEXT_TX(greth->tx_last);
dma_unmap_single(greth->dev,
greth_read_bd(&tx_bdp->addr),
skb_headlen(skb),
DMA_TO_DEVICE);
for (i = 0; i < nr_frags; i++) {
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
tx_bdp = greth->tx_bd_base + greth->tx_last;
dma_unmap_page(greth->dev,
greth_read_bd(&tx_bdp->addr),
frag->size,
DMA_TO_DEVICE);
greth->tx_last = NEXT_TX(greth->tx_last);
}
greth->tx_free += nr_frags+1;
dev_kfree_skb(skb);
}
} else { /* 10/100 Mbps MAC */
for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
kfree(greth->rx_bufs[i]);
dma_unmap_single(greth->dev,
greth_read_bd(&rx_bdp->addr),
MAX_FRAME_SIZE,
DMA_FROM_DEVICE);
}
for (i = 0; i < GRETH_TXBD_NUM; i++, tx_bdp++) {
kfree(greth->tx_bufs[i]);
dma_unmap_single(greth->dev,
greth_read_bd(&tx_bdp->addr),
MAX_FRAME_SIZE,
DMA_TO_DEVICE);
}
}
}
static int greth_init_rings(struct greth_private *greth)
{
struct sk_buff *skb;
struct greth_bd *rx_bd, *tx_bd;
u32 dma_addr;
int i;
rx_bd = greth->rx_bd_base;
tx_bd = greth->tx_bd_base;
/* Initialize descriptor rings and buffers */
if (greth->gbit_mac) {
for (i = 0; i < GRETH_RXBD_NUM; i++) {
skb = netdev_alloc_skb(greth->netdev, MAX_FRAME_SIZE+NET_IP_ALIGN);
if (skb == NULL) {
if (netif_msg_ifup(greth))
dev_err(greth->dev, "Error allocating DMA ring.\n");
goto cleanup;
}
skb_reserve(skb, NET_IP_ALIGN);
dma_addr = dma_map_single(greth->dev,
skb->data,
MAX_FRAME_SIZE+NET_IP_ALIGN,
DMA_FROM_DEVICE);
if (dma_mapping_error(greth->dev, dma_addr)) {
if (netif_msg_ifup(greth))
dev_err(greth->dev, "Could not create initial DMA mapping\n");
goto cleanup;
}
greth->rx_skbuff[i] = skb;
greth_write_bd(&rx_bd[i].addr, dma_addr);
greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
}
} else {
/* 10/100 MAC uses a fixed set of buffers and copy to/from SKBs */
for (i = 0; i < GRETH_RXBD_NUM; i++) {
greth->rx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
if (greth->rx_bufs[i] == NULL) {
if (netif_msg_ifup(greth))
dev_err(greth->dev, "Error allocating DMA ring.\n");
goto cleanup;
}
dma_addr = dma_map_single(greth->dev,
greth->rx_bufs[i],
MAX_FRAME_SIZE,
DMA_FROM_DEVICE);
if (dma_mapping_error(greth->dev, dma_addr)) {
if (netif_msg_ifup(greth))
dev_err(greth->dev, "Could not create initial DMA mapping\n");
goto cleanup;
}
greth_write_bd(&rx_bd[i].addr, dma_addr);
greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
}
for (i = 0; i < GRETH_TXBD_NUM; i++) {
greth->tx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
if (greth->tx_bufs[i] == NULL) {
if (netif_msg_ifup(greth))
dev_err(greth->dev, "Error allocating DMA ring.\n");
goto cleanup;
}
dma_addr = dma_map_single(greth->dev,
greth->tx_bufs[i],
MAX_FRAME_SIZE,
DMA_TO_DEVICE);
if (dma_mapping_error(greth->dev, dma_addr)) {
if (netif_msg_ifup(greth))
dev_err(greth->dev, "Could not create initial DMA mapping\n");
goto cleanup;
}
greth_write_bd(&tx_bd[i].addr, dma_addr);
greth_write_bd(&tx_bd[i].stat, 0);
}
}
greth_write_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat,
greth_read_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat) | GRETH_BD_WR);
/* Initialize pointers. */
greth->rx_cur = 0;
greth->tx_next = 0;
greth->tx_last = 0;
greth->tx_free = GRETH_TXBD_NUM;
/* Initialize descriptor base address */
GRETH_REGSAVE(greth->regs->tx_desc_p, greth->tx_bd_base_phys);
GRETH_REGSAVE(greth->regs->rx_desc_p, greth->rx_bd_base_phys);
return 0;
cleanup:
greth_clean_rings(greth);
return -ENOMEM;
}
static int greth_open(struct net_device *dev)
{
struct greth_private *greth = netdev_priv(dev);
int err;
err = greth_init_rings(greth);
if (err) {
if (netif_msg_ifup(greth))
dev_err(&dev->dev, "Could not allocate memory for DMA rings\n");
return err;
}
err = request_irq(greth->irq, greth_interrupt, 0, "eth", (void *) dev);
if (err) {
if (netif_msg_ifup(greth))
dev_err(&dev->dev, "Could not allocate interrupt %d\n", dev->irq);
greth_clean_rings(greth);
return err;
}
if (netif_msg_ifup(greth))
dev_dbg(&dev->dev, " starting queue\n");
netif_start_queue(dev);
GRETH_REGSAVE(greth->regs->status, 0xFF);
napi_enable(&greth->napi);
greth_enable_irqs(greth);
greth_enable_tx(greth);
greth_enable_rx(greth);
return 0;
}
static int greth_close(struct net_device *dev)
{
struct greth_private *greth = netdev_priv(dev);
napi_disable(&greth->napi);
greth_disable_irqs(greth);
greth_disable_tx(greth);
greth_disable_rx(greth);
netif_stop_queue(dev);
free_irq(greth->irq, (void *) dev);
greth_clean_rings(greth);
return 0;
}
static netdev_tx_t
greth_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct greth_private *greth = netdev_priv(dev);
struct greth_bd *bdp;
int err = NETDEV_TX_OK;
u32 status, dma_addr, ctrl;
unsigned long flags;
/* Clean TX Ring */
greth_clean_tx(greth->netdev);
if (unlikely(greth->tx_free <= 0)) {
spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
ctrl = GRETH_REGLOAD(greth->regs->control);
/* Enable TX IRQ only if not already in poll() routine */
if (ctrl & GRETH_RXI)
GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
netif_stop_queue(dev);
spin_unlock_irqrestore(&greth->devlock, flags);
return NETDEV_TX_BUSY;
}
if (netif_msg_pktdata(greth))
greth_print_tx_packet(skb);
if (unlikely(skb->len > MAX_FRAME_SIZE)) {
dev->stats.tx_errors++;
goto out;
}
bdp = greth->tx_bd_base + greth->tx_next;
dma_addr = greth_read_bd(&bdp->addr);
memcpy((unsigned char *) phys_to_virt(dma_addr), skb->data, skb->len);
dma_sync_single_for_device(greth->dev, dma_addr, skb->len, DMA_TO_DEVICE);
status = GRETH_BD_EN | GRETH_BD_IE | (skb->len & GRETH_BD_LEN);
/* Wrap around descriptor ring */
if (greth->tx_next == GRETH_TXBD_NUM_MASK) {
status |= GRETH_BD_WR;
}
greth->tx_next = NEXT_TX(greth->tx_next);
greth->tx_free--;
/* Write descriptor control word and enable transmission */
greth_write_bd(&bdp->stat, status);
spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
greth_enable_tx(greth);
spin_unlock_irqrestore(&greth->devlock, flags);
out:
dev_kfree_skb(skb);
return err;
}
static netdev_tx_t
greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
{
struct greth_private *greth = netdev_priv(dev);
struct greth_bd *bdp;
u32 status = 0, dma_addr, ctrl;
int curr_tx, nr_frags, i, err = NETDEV_TX_OK;
unsigned long flags;
nr_frags = skb_shinfo(skb)->nr_frags;
/* Clean TX Ring */
greth_clean_tx_gbit(dev);
if (greth->tx_free < nr_frags + 1) {
spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
ctrl = GRETH_REGLOAD(greth->regs->control);
/* Enable TX IRQ only if not already in poll() routine */
if (ctrl & GRETH_RXI)
GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
netif_stop_queue(dev);
spin_unlock_irqrestore(&greth->devlock, flags);
err = NETDEV_TX_BUSY;
goto out;
}
if (netif_msg_pktdata(greth))
greth_print_tx_packet(skb);
if (unlikely(skb->len > MAX_FRAME_SIZE)) {
dev->stats.tx_errors++;
goto out;
}
/* Save skb pointer. */
greth->tx_skbuff[greth->tx_next] = skb;
/* Linear buf */
if (nr_frags != 0)
status = GRETH_TXBD_MORE;
status |= GRETH_TXBD_CSALL;
status |= skb_headlen(skb) & GRETH_BD_LEN;
if (greth->tx_next == GRETH_TXBD_NUM_MASK)
status |= GRETH_BD_WR;
bdp = greth->tx_bd_base + greth->tx_next;
greth_write_bd(&bdp->stat, status);
dma_addr = dma_map_single(greth->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
goto map_error;
greth_write_bd(&bdp->addr, dma_addr);
curr_tx = NEXT_TX(greth->tx_next);
/* Frags */
for (i = 0; i < nr_frags; i++) {
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
greth->tx_skbuff[curr_tx] = NULL;
bdp = greth->tx_bd_base + curr_tx;
status = GRETH_TXBD_CSALL | GRETH_BD_EN;
status |= frag->size & GRETH_BD_LEN;
/* Wrap around descriptor ring */
if (curr_tx == GRETH_TXBD_NUM_MASK)
status |= GRETH_BD_WR;
/* More fragments left */
if (i < nr_frags - 1)
status |= GRETH_TXBD_MORE;
else
status |= GRETH_BD_IE; /* enable IRQ on last fragment */
greth_write_bd(&bdp->stat, status);
dma_addr = dma_map_page(greth->dev,
frag->page,
frag->page_offset,
frag->size,
DMA_TO_DEVICE);
if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
goto frag_map_error;
greth_write_bd(&bdp->addr, dma_addr);
curr_tx = NEXT_TX(curr_tx);
}
wmb();
/* Enable the descriptor chain by enabling the first descriptor */
bdp = greth->tx_bd_base + greth->tx_next;
greth_write_bd(&bdp->stat, greth_read_bd(&bdp->stat) | GRETH_BD_EN);
greth->tx_next = curr_tx;
greth->tx_free -= nr_frags + 1;
wmb();
spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
greth_enable_tx(greth);
spin_unlock_irqrestore(&greth->devlock, flags);
return NETDEV_TX_OK;
frag_map_error:
/* Unmap SKB mappings that succeeded and disable descriptor */
for (i = 0; greth->tx_next + i != curr_tx; i++) {
bdp = greth->tx_bd_base + greth->tx_next + i;
dma_unmap_single(greth->dev,
greth_read_bd(&bdp->addr),
greth_read_bd(&bdp->stat) & GRETH_BD_LEN,
DMA_TO_DEVICE);
greth_write_bd(&bdp->stat, 0);
}
map_error:
if (net_ratelimit())
dev_warn(greth->dev, "Could not create TX DMA mapping\n");
dev_kfree_skb(skb);
out:
return err;
}
static irqreturn_t greth_interrupt(int irq, void *dev_id)
{
struct net_device *dev = dev_id;
struct greth_private *greth;
u32 status, ctrl;
irqreturn_t retval = IRQ_NONE;
greth = netdev_priv(dev);
spin_lock(&greth->devlock);
/* Get the interrupt events that caused us to be here. */
status = GRETH_REGLOAD(greth->regs->status);
/* Must see if interrupts are enabled also, INT_TX|INT_RX flags may be
* set regardless of whether IRQ is enabled or not. Especially
* important when shared IRQ.
*/
ctrl = GRETH_REGLOAD(greth->regs->control);
/* Handle rx and tx interrupts through poll */
if (((status & (GRETH_INT_RE | GRETH_INT_RX)) && (ctrl & GRETH_RXI)) ||
((status & (GRETH_INT_TE | GRETH_INT_TX)) && (ctrl & GRETH_TXI))) {
retval = IRQ_HANDLED;
/* Disable interrupts and schedule poll() */
greth_disable_irqs(greth);
napi_schedule(&greth->napi);
}
mmiowb();
spin_unlock(&greth->devlock);
return retval;
}
static void greth_clean_tx(struct net_device *dev)
{
struct greth_private *greth;
struct greth_bd *bdp;
u32 stat;
greth = netdev_priv(dev);
while (1) {
bdp = greth->tx_bd_base + greth->tx_last;
GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
mb();
stat = greth_read_bd(&bdp->stat);
if (unlikely(stat & GRETH_BD_EN))
break;
if (greth->tx_free == GRETH_TXBD_NUM)
break;
/* Check status for errors */
if (unlikely(stat & GRETH_TXBD_STATUS)) {
dev->stats.tx_errors++;
if (stat & GRETH_TXBD_ERR_AL)
dev->stats.tx_aborted_errors++;
if (stat & GRETH_TXBD_ERR_UE)
dev->stats.tx_fifo_errors++;
}
dev->stats.tx_packets++;
greth->tx_last = NEXT_TX(greth->tx_last);
greth->tx_free++;
}
if (greth->tx_free > 0) {
netif_wake_queue(dev);
}
}
static inline void greth_update_tx_stats(struct net_device *dev, u32 stat)
{
/* Check status for errors */
if (unlikely(stat & GRETH_TXBD_STATUS)) {
dev->stats.tx_errors++;
if (stat & GRETH_TXBD_ERR_AL)
dev->stats.tx_aborted_errors++;
if (stat & GRETH_TXBD_ERR_UE)
dev->stats.tx_fifo_errors++;
if (stat & GRETH_TXBD_ERR_LC)
dev->stats.tx_aborted_errors++;
}
dev->stats.tx_packets++;
}
static void greth_clean_tx_gbit(struct net_device *dev)
{
struct greth_private *greth;
struct greth_bd *bdp, *bdp_last_frag;
struct sk_buff *skb;
u32 stat;
int nr_frags, i;
greth = netdev_priv(dev);
while (greth->tx_free < GRETH_TXBD_NUM) {
skb = greth->tx_skbuff[greth->tx_last];
nr_frags = skb_shinfo(skb)->nr_frags;
/* We only clean fully completed SKBs */
bdp_last_frag = greth->tx_bd_base + SKIP_TX(greth->tx_last, nr_frags);
GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
mb();
stat = greth_read_bd(&bdp_last_frag->stat);
if (stat & GRETH_BD_EN)
break;
greth->tx_skbuff[greth->tx_last] = NULL;
greth_update_tx_stats(dev, stat);
bdp = greth->tx_bd_base + greth->tx_last;
greth->tx_last = NEXT_TX(greth->tx_last);
dma_unmap_single(greth->dev,
greth_read_bd(&bdp->addr),
skb_headlen(skb),
DMA_TO_DEVICE);
for (i = 0; i < nr_frags; i++) {
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
bdp = greth->tx_bd_base + greth->tx_last;
dma_unmap_page(greth->dev,
greth_read_bd(&bdp->addr),
frag->size,
DMA_TO_DEVICE);
greth->tx_last = NEXT_TX(greth->tx_last);
}
greth->tx_free += nr_frags+1;
dev_kfree_skb(skb);
}
if (netif_queue_stopped(dev) && (greth->tx_free > (MAX_SKB_FRAGS+1)))
netif_wake_queue(dev);
}
static int greth_rx(struct net_device *dev, int limit)
{
struct greth_private *greth;
struct greth_bd *bdp;
struct sk_buff *skb;
int pkt_len;
int bad, count;
u32 status, dma_addr;
unsigned long flags;
greth = netdev_priv(dev);
for (count = 0; count < limit; ++count) {
bdp = greth->rx_bd_base + greth->rx_cur;
GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
mb();
status = greth_read_bd(&bdp->stat);
if (unlikely(status & GRETH_BD_EN)) {
break;
}
dma_addr = greth_read_bd(&bdp->addr);
bad = 0;
/* Check status for errors. */
if (unlikely(status & GRETH_RXBD_STATUS)) {
if (status & GRETH_RXBD_ERR_FT) {
dev->stats.rx_length_errors++;
bad = 1;
}
if (status & (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE)) {
dev->stats.rx_frame_errors++;
bad = 1;
}
if (status & GRETH_RXBD_ERR_CRC) {
dev->stats.rx_crc_errors++;
bad = 1;
}
}
if (unlikely(bad)) {
dev->stats.rx_errors++;
} else {
pkt_len = status & GRETH_BD_LEN;
skb = netdev_alloc_skb(dev, pkt_len + NET_IP_ALIGN);
if (unlikely(skb == NULL)) {
if (net_ratelimit())
dev_warn(&dev->dev, "low on memory - " "packet dropped\n");
dev->stats.rx_dropped++;
} else {
skb_reserve(skb, NET_IP_ALIGN);
skb->dev = dev;
dma_sync_single_for_cpu(greth->dev,
dma_addr,
pkt_len,
DMA_FROM_DEVICE);
if (netif_msg_pktdata(greth))
greth_print_rx_packet(phys_to_virt(dma_addr), pkt_len);
memcpy(skb_put(skb, pkt_len), phys_to_virt(dma_addr), pkt_len);
skb->protocol = eth_type_trans(skb, dev);
dev->stats.rx_packets++;
netif_receive_skb(skb);
}
}
status = GRETH_BD_EN | GRETH_BD_IE;
if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
status |= GRETH_BD_WR;
}
wmb();
greth_write_bd(&bdp->stat, status);
dma_sync_single_for_device(greth->dev, dma_addr, MAX_FRAME_SIZE, DMA_FROM_DEVICE);
spin_lock_irqsave(&greth->devlock, flags); /* save from XMIT */
greth_enable_rx(greth);
spin_unlock_irqrestore(&greth->devlock, flags);
greth->rx_cur = NEXT_RX(greth->rx_cur);
}
return count;
}
static inline int hw_checksummed(u32 status)
{
if (status & GRETH_RXBD_IP_FRAG)
return 0;
if (status & GRETH_RXBD_IP && status & GRETH_RXBD_IP_CSERR)
return 0;
if (status & GRETH_RXBD_UDP && status & GRETH_RXBD_UDP_CSERR)
return 0;
if (status & GRETH_RXBD_TCP && status & GRETH_RXBD_TCP_CSERR)
return 0;
return 1;
}
static int greth_rx_gbit(struct net_device *dev, int limit)
{
struct greth_private *greth;
struct greth_bd *bdp;
struct sk_buff *skb, *newskb;
int pkt_len;
int bad, count = 0;
u32 status, dma_addr;
unsigned long flags;
greth = netdev_priv(dev);
for (count = 0; count < limit; ++count) {
bdp = greth->rx_bd_base + greth->rx_cur;
skb = greth->rx_skbuff[greth->rx_cur];
GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
mb();
status = greth_read_bd(&bdp->stat);
bad = 0;
if (status & GRETH_BD_EN)
break;
/* Check status for errors. */
if (unlikely(status & GRETH_RXBD_STATUS)) {
if (status & GRETH_RXBD_ERR_FT) {
dev->stats.rx_length_errors++;
bad = 1;
} else if (status &
(GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE | GRETH_RXBD_ERR_LE)) {
dev->stats.rx_frame_errors++;
bad = 1;
} else if (status & GRETH_RXBD_ERR_CRC) {
dev->stats.rx_crc_errors++;
bad = 1;
}
}
/* Allocate new skb to replace current, not needed if the
* current skb can be reused */
if (!bad && (newskb=netdev_alloc_skb(dev, MAX_FRAME_SIZE + NET_IP_ALIGN))) {
skb_reserve(newskb, NET_IP_ALIGN);
dma_addr = dma_map_single(greth->dev,
newskb->data,
MAX_FRAME_SIZE + NET_IP_ALIGN,
DMA_FROM_DEVICE);
if (!dma_mapping_error(greth->dev, dma_addr)) {
/* Process the incoming frame. */
pkt_len = status & GRETH_BD_LEN;
dma_unmap_single(greth->dev,
greth_read_bd(&bdp->addr),
MAX_FRAME_SIZE + NET_IP_ALIGN,
DMA_FROM_DEVICE);
if (netif_msg_pktdata(greth))
greth_print_rx_packet(phys_to_virt(greth_read_bd(&bdp->addr)), pkt_len);
skb_put(skb, pkt_len);
if (dev->features & NETIF_F_RXCSUM && hw_checksummed(status))
skb->ip_summed = CHECKSUM_UNNECESSARY;
else
skb_checksum_none_assert(skb);
skb->protocol = eth_type_trans(skb, dev);
dev->stats.rx_packets++;
netif_receive_skb(skb);
greth->rx_skbuff[greth->rx_cur] = newskb;
greth_write_bd(&bdp->addr, dma_addr);
} else {
if (net_ratelimit())
dev_warn(greth->dev, "Could not create DMA mapping, dropping packet\n");
dev_kfree_skb(newskb);
/* reusing current skb, so it is a drop */
dev->stats.rx_dropped++;
}
} else if (bad) {
/* Bad Frame transfer, the skb is reused */
dev->stats.rx_dropped++;
} else {
/* Failed Allocating a new skb. This is rather stupid
* but the current "filled" skb is reused, as if
* transfer failure. One could argue that RX descriptor
* table handling should be divided into cleaning and
* filling as the TX part of the driver
*/
if (net_ratelimit())
dev_warn(greth->dev, "Could not allocate SKB, dropping packet\n");
/* reusing current skb, so it is a drop */
dev->stats.rx_dropped++;
}
status = GRETH_BD_EN | GRETH_BD_IE;
if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
status |= GRETH_BD_WR;
}
wmb();
greth_write_bd(&bdp->stat, status);
spin_lock_irqsave(&greth->devlock, flags);
greth_enable_rx(greth);
spin_unlock_irqrestore(&greth->devlock, flags);
greth->rx_cur = NEXT_RX(greth->rx_cur);
}
return count;
}
static int greth_poll(struct napi_struct *napi, int budget)
{
struct greth_private *greth;
int work_done = 0;
unsigned long flags;
u32 mask, ctrl;
greth = container_of(napi, struct greth_private, napi);
restart_txrx_poll:
if (netif_queue_stopped(greth->netdev)) {
if (greth->gbit_mac)
greth_clean_tx_gbit(greth->netdev);
else
greth_clean_tx(greth->netdev);
}
if (greth->gbit_mac) {
work_done += greth_rx_gbit(greth->netdev, budget - work_done);
} else {
work_done += greth_rx(greth->netdev, budget - work_done);
}
if (work_done < budget) {
spin_lock_irqsave(&greth->devlock, flags);
ctrl = GRETH_REGLOAD(greth->regs->control);
if (netif_queue_stopped(greth->netdev)) {
GRETH_REGSAVE(greth->regs->control,
ctrl | GRETH_TXI | GRETH_RXI);
mask = GRETH_INT_RX | GRETH_INT_RE |
GRETH_INT_TX | GRETH_INT_TE;
} else {
GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_RXI);
mask = GRETH_INT_RX | GRETH_INT_RE;
}
if (GRETH_REGLOAD(greth->regs->status) & mask) {
GRETH_REGSAVE(greth->regs->control, ctrl);
spin_unlock_irqrestore(&greth->devlock, flags);
goto restart_txrx_poll;
} else {
__napi_complete(napi);
spin_unlock_irqrestore(&greth->devlock, flags);
}
}