linux/drivers/net/ks8851.c
Tristram Ha 3320eae51d net: Fix ks8851 snl NULL pointer dereference Oops
This fixes the NULL pointer dereference Oops in the ks8851 snl network
driver during transmission.  All socket buffers from the queue are
processed inside the loop, but new workqueues have been scheduled to
run.

Signed-off-by: Tristram Ha <Tristram.Ha@micrel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-03 16:04:25 -08:00

1356 lines
35 KiB
C

/* drivers/net/ks8851.c
*
* Copyright 2009 Simtec Electronics
* http://www.simtec.co.uk/
* Ben Dooks <ben@simtec.co.uk>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#define DEBUG
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/cache.h>
#include <linux/crc32.h>
#include <linux/mii.h>
#include <linux/spi/spi.h>
#include "ks8851.h"
/**
* struct ks8851_rxctrl - KS8851 driver rx control
* @mchash: Multicast hash-table data.
* @rxcr1: KS_RXCR1 register setting
* @rxcr2: KS_RXCR2 register setting
*
* Representation of the settings needs to control the receive filtering
* such as the multicast hash-filter and the receive register settings. This
* is used to make the job of working out if the receive settings change and
* then issuing the new settings to the worker that will send the necessary
* commands.
*/
struct ks8851_rxctrl {
u16 mchash[4];
u16 rxcr1;
u16 rxcr2;
};
/**
* union ks8851_tx_hdr - tx header data
* @txb: The header as bytes
* @txw: The header as 16bit, little-endian words
*
* A dual representation of the tx header data to allow
* access to individual bytes, and to allow 16bit accesses
* with 16bit alignment.
*/
union ks8851_tx_hdr {
u8 txb[6];
__le16 txw[3];
};
/**
* struct ks8851_net - KS8851 driver private data
* @netdev: The network device we're bound to
* @spidev: The spi device we're bound to.
* @lock: Lock to ensure that the device is not accessed when busy.
* @statelock: Lock on this structure for tx list.
* @mii: The MII state information for the mii calls.
* @rxctrl: RX settings for @rxctrl_work.
* @tx_work: Work queue for tx packets
* @irq_work: Work queue for servicing interrupts
* @rxctrl_work: Work queue for updating RX mode and multicast lists
* @txq: Queue of packets for transmission.
* @spi_msg1: pre-setup SPI transfer with one message, @spi_xfer1.
* @spi_msg2: pre-setup SPI transfer with two messages, @spi_xfer2.
* @txh: Space for generating packet TX header in DMA-able data
* @rxd: Space for receiving SPI data, in DMA-able space.
* @txd: Space for transmitting SPI data, in DMA-able space.
* @msg_enable: The message flags controlling driver output (see ethtool).
* @fid: Incrementing frame id tag.
* @rc_ier: Cached copy of KS_IER.
* @rc_rxqcr: Cached copy of KS_RXQCR.
*
* The @lock ensures that the chip is protected when certain operations are
* in progress. When the read or write packet transfer is in progress, most
* of the chip registers are not ccessible until the transfer is finished and
* the DMA has been de-asserted.
*
* The @statelock is used to protect information in the structure which may
* need to be accessed via several sources, such as the network driver layer
* or one of the work queues.
*
* We align the buffers we may use for rx/tx to ensure that if the SPI driver
* wants to DMA map them, it will not have any problems with data the driver
* modifies.
*/
struct ks8851_net {
struct net_device *netdev;
struct spi_device *spidev;
struct mutex lock;
spinlock_t statelock;
union ks8851_tx_hdr txh ____cacheline_aligned;
u8 rxd[8];
u8 txd[8];
u32 msg_enable ____cacheline_aligned;
u16 tx_space;
u8 fid;
u16 rc_ier;
u16 rc_rxqcr;
struct mii_if_info mii;
struct ks8851_rxctrl rxctrl;
struct work_struct tx_work;
struct work_struct irq_work;
struct work_struct rxctrl_work;
struct sk_buff_head txq;
struct spi_message spi_msg1;
struct spi_message spi_msg2;
struct spi_transfer spi_xfer1;
struct spi_transfer spi_xfer2[2];
};
static int msg_enable;
#define ks_info(_ks, _msg...) dev_info(&(_ks)->spidev->dev, _msg)
#define ks_warn(_ks, _msg...) dev_warn(&(_ks)->spidev->dev, _msg)
#define ks_dbg(_ks, _msg...) dev_dbg(&(_ks)->spidev->dev, _msg)
#define ks_err(_ks, _msg...) dev_err(&(_ks)->spidev->dev, _msg)
/* shift for byte-enable data */
#define BYTE_EN(_x) ((_x) << 2)
/* turn register number and byte-enable mask into data for start of packet */
#define MK_OP(_byteen, _reg) (BYTE_EN(_byteen) | (_reg) << (8+2) | (_reg) >> 6)
/* SPI register read/write calls.
*
* All these calls issue SPI transactions to access the chip's registers. They
* all require that the necessary lock is held to prevent accesses when the
* chip is busy transfering packet data (RX/TX FIFO accesses).
*/
/**
* ks8851_wrreg16 - write 16bit register value to chip
* @ks: The chip state
* @reg: The register address
* @val: The value to write
*
* Issue a write to put the value @val into the register specified in @reg.
*/
static void ks8851_wrreg16(struct ks8851_net *ks, unsigned reg, unsigned val)
{
struct spi_transfer *xfer = &ks->spi_xfer1;
struct spi_message *msg = &ks->spi_msg1;
__le16 txb[2];
int ret;
txb[0] = cpu_to_le16(MK_OP(reg & 2 ? 0xC : 0x03, reg) | KS_SPIOP_WR);
txb[1] = cpu_to_le16(val);
xfer->tx_buf = txb;
xfer->rx_buf = NULL;
xfer->len = 4;
ret = spi_sync(ks->spidev, msg);
if (ret < 0)
ks_err(ks, "spi_sync() failed\n");
}
/**
* ks8851_wrreg8 - write 8bit register value to chip
* @ks: The chip state
* @reg: The register address
* @val: The value to write
*
* Issue a write to put the value @val into the register specified in @reg.
*/
static void ks8851_wrreg8(struct ks8851_net *ks, unsigned reg, unsigned val)
{
struct spi_transfer *xfer = &ks->spi_xfer1;
struct spi_message *msg = &ks->spi_msg1;
__le16 txb[2];
int ret;
int bit;
bit = 1 << (reg & 3);
txb[0] = cpu_to_le16(MK_OP(bit, reg) | KS_SPIOP_WR);
txb[1] = val;
xfer->tx_buf = txb;
xfer->rx_buf = NULL;
xfer->len = 3;
ret = spi_sync(ks->spidev, msg);
if (ret < 0)
ks_err(ks, "spi_sync() failed\n");
}
/**
* ks8851_rx_1msg - select whether to use one or two messages for spi read
* @ks: The device structure
*
* Return whether to generate a single message with a tx and rx buffer
* supplied to spi_sync(), or alternatively send the tx and rx buffers
* as separate messages.
*
* Depending on the hardware in use, a single message may be more efficient
* on interrupts or work done by the driver.
*
* This currently always returns true until we add some per-device data passed
* from the platform code to specify which mode is better.
*/
static inline bool ks8851_rx_1msg(struct ks8851_net *ks)
{
return true;
}
/**
* ks8851_rdreg - issue read register command and return the data
* @ks: The device state
* @op: The register address and byte enables in message format.
* @rxb: The RX buffer to return the result into
* @rxl: The length of data expected.
*
* This is the low level read call that issues the necessary spi message(s)
* to read data from the register specified in @op.
*/
static void ks8851_rdreg(struct ks8851_net *ks, unsigned op,
u8 *rxb, unsigned rxl)
{
struct spi_transfer *xfer;
struct spi_message *msg;
__le16 *txb = (__le16 *)ks->txd;
u8 *trx = ks->rxd;
int ret;
txb[0] = cpu_to_le16(op | KS_SPIOP_RD);
if (ks8851_rx_1msg(ks)) {
msg = &ks->spi_msg1;
xfer = &ks->spi_xfer1;
xfer->tx_buf = txb;
xfer->rx_buf = trx;
xfer->len = rxl + 2;
} else {
msg = &ks->spi_msg2;
xfer = ks->spi_xfer2;
xfer->tx_buf = txb;
xfer->rx_buf = NULL;
xfer->len = 2;
xfer++;
xfer->tx_buf = NULL;
xfer->rx_buf = trx;
xfer->len = rxl;
}
ret = spi_sync(ks->spidev, msg);
if (ret < 0)
ks_err(ks, "read: spi_sync() failed\n");
else if (ks8851_rx_1msg(ks))
memcpy(rxb, trx + 2, rxl);
else
memcpy(rxb, trx, rxl);
}
/**
* ks8851_rdreg8 - read 8 bit register from device
* @ks: The chip information
* @reg: The register address
*
* Read a 8bit register from the chip, returning the result
*/
static unsigned ks8851_rdreg8(struct ks8851_net *ks, unsigned reg)
{
u8 rxb[1];
ks8851_rdreg(ks, MK_OP(1 << (reg & 3), reg), rxb, 1);
return rxb[0];
}
/**
* ks8851_rdreg16 - read 16 bit register from device
* @ks: The chip information
* @reg: The register address
*
* Read a 16bit register from the chip, returning the result
*/
static unsigned ks8851_rdreg16(struct ks8851_net *ks, unsigned reg)
{
__le16 rx = 0;
ks8851_rdreg(ks, MK_OP(reg & 2 ? 0xC : 0x3, reg), (u8 *)&rx, 2);
return le16_to_cpu(rx);
}
/**
* ks8851_rdreg32 - read 32 bit register from device
* @ks: The chip information
* @reg: The register address
*
* Read a 32bit register from the chip.
*
* Note, this read requires the address be aligned to 4 bytes.
*/
static unsigned ks8851_rdreg32(struct ks8851_net *ks, unsigned reg)
{
__le32 rx = 0;
WARN_ON(reg & 3);
ks8851_rdreg(ks, MK_OP(0xf, reg), (u8 *)&rx, 4);
return le32_to_cpu(rx);
}
/**
* ks8851_soft_reset - issue one of the soft reset to the device
* @ks: The device state.
* @op: The bit(s) to set in the GRR
*
* Issue the relevant soft-reset command to the device's GRR register
* specified by @op.
*
* Note, the delays are in there as a caution to ensure that the reset
* has time to take effect and then complete. Since the datasheet does
* not currently specify the exact sequence, we have chosen something
* that seems to work with our device.
*/
static void ks8851_soft_reset(struct ks8851_net *ks, unsigned op)
{
ks8851_wrreg16(ks, KS_GRR, op);
mdelay(1); /* wait a short time to effect reset */
ks8851_wrreg16(ks, KS_GRR, 0);
mdelay(1); /* wait for condition to clear */
}
/**
* ks8851_write_mac_addr - write mac address to device registers
* @dev: The network device
*
* Update the KS8851 MAC address registers from the address in @dev.
*
* This call assumes that the chip is not running, so there is no need to
* shutdown the RXQ process whilst setting this.
*/
static int ks8851_write_mac_addr(struct net_device *dev)
{
struct ks8851_net *ks = netdev_priv(dev);
int i;
mutex_lock(&ks->lock);
for (i = 0; i < ETH_ALEN; i++)
ks8851_wrreg8(ks, KS_MAR(i), dev->dev_addr[i]);
mutex_unlock(&ks->lock);
return 0;
}
/**
* ks8851_init_mac - initialise the mac address
* @ks: The device structure
*
* Get or create the initial mac address for the device and then set that
* into the station address register. Currently we assume that the device
* does not have a valid mac address in it, and so we use random_ether_addr()
* to create a new one.
*
* In future, the driver should check to see if the device has an EEPROM
* attached and whether that has a valid ethernet address in it.
*/
static void ks8851_init_mac(struct ks8851_net *ks)
{
struct net_device *dev = ks->netdev;
random_ether_addr(dev->dev_addr);
ks8851_write_mac_addr(dev);
}
/**
* ks8851_irq - device interrupt handler
* @irq: Interrupt number passed from the IRQ hnalder.
* @pw: The private word passed to register_irq(), our struct ks8851_net.
*
* Disable the interrupt from happening again until we've processed the
* current status by scheduling ks8851_irq_work().
*/
static irqreturn_t ks8851_irq(int irq, void *pw)
{
struct ks8851_net *ks = pw;
disable_irq_nosync(irq);
schedule_work(&ks->irq_work);
return IRQ_HANDLED;
}
/**
* ks8851_rdfifo - read data from the receive fifo
* @ks: The device state.
* @buff: The buffer address
* @len: The length of the data to read
*
* Issue an RXQ FIFO read command and read the @len ammount of data from
* the FIFO into the buffer specified by @buff.
*/
static void ks8851_rdfifo(struct ks8851_net *ks, u8 *buff, unsigned len)
{
struct spi_transfer *xfer = ks->spi_xfer2;
struct spi_message *msg = &ks->spi_msg2;
u8 txb[1];
int ret;
if (netif_msg_rx_status(ks))
ks_dbg(ks, "%s: %d@%p\n", __func__, len, buff);
/* set the operation we're issuing */
txb[0] = KS_SPIOP_RXFIFO;
xfer->tx_buf = txb;
xfer->rx_buf = NULL;
xfer->len = 1;
xfer++;
xfer->rx_buf = buff;
xfer->tx_buf = NULL;
xfer->len = len;
ret = spi_sync(ks->spidev, msg);
if (ret < 0)
ks_err(ks, "%s: spi_sync() failed\n", __func__);
}
/**
* ks8851_dbg_dumpkkt - dump initial packet contents to debug
* @ks: The device state
* @rxpkt: The data for the received packet
*
* Dump the initial data from the packet to dev_dbg().
*/
static void ks8851_dbg_dumpkkt(struct ks8851_net *ks, u8 *rxpkt)
{
ks_dbg(ks, "pkt %02x%02x%02x%02x %02x%02x%02x%02x %02x%02x%02x%02x\n",
rxpkt[4], rxpkt[5], rxpkt[6], rxpkt[7],
rxpkt[8], rxpkt[9], rxpkt[10], rxpkt[11],
rxpkt[12], rxpkt[13], rxpkt[14], rxpkt[15]);
}
/**
* ks8851_rx_pkts - receive packets from the host
* @ks: The device information.
*
* This is called from the IRQ work queue when the system detects that there
* are packets in the receive queue. Find out how many packets there are and
* read them from the FIFO.
*/
static void ks8851_rx_pkts(struct ks8851_net *ks)
{
struct sk_buff *skb;
unsigned rxfc;
unsigned rxlen;
unsigned rxstat;
u32 rxh;
u8 *rxpkt;
rxfc = ks8851_rdreg8(ks, KS_RXFC);
if (netif_msg_rx_status(ks))
ks_dbg(ks, "%s: %d packets\n", __func__, rxfc);
/* Currently we're issuing a read per packet, but we could possibly
* improve the code by issuing a single read, getting the receive
* header, allocating the packet and then reading the packet data
* out in one go.
*
* This form of operation would require us to hold the SPI bus'
* chipselect low during the entie transaction to avoid any
* reset to the data stream comming from the chip.
*/
for (; rxfc != 0; rxfc--) {
rxh = ks8851_rdreg32(ks, KS_RXFHSR);
rxstat = rxh & 0xffff;
rxlen = rxh >> 16;
if (netif_msg_rx_status(ks))
ks_dbg(ks, "rx: stat 0x%04x, len 0x%04x\n",
rxstat, rxlen);
/* the length of the packet includes the 32bit CRC */
/* set dma read address */
ks8851_wrreg16(ks, KS_RXFDPR, RXFDPR_RXFPAI | 0x00);
/* start the packet dma process, and set auto-dequeue rx */
ks8851_wrreg16(ks, KS_RXQCR,
ks->rc_rxqcr | RXQCR_SDA | RXQCR_ADRFE);
if (rxlen > 0) {
skb = netdev_alloc_skb(ks->netdev, rxlen + 2 + 8);
if (!skb) {
/* todo - dump frame and move on */
}
/* two bytes to ensure ip is aligned, and four bytes
* for the status header and 4 bytes of garbage */
skb_reserve(skb, 2 + 4 + 4);
rxpkt = skb_put(skb, rxlen - 4) - 8;
/* align the packet length to 4 bytes, and add 4 bytes
* as we're getting the rx status header as well */
ks8851_rdfifo(ks, rxpkt, ALIGN(rxlen, 4) + 8);
if (netif_msg_pktdata(ks))
ks8851_dbg_dumpkkt(ks, rxpkt);
skb->protocol = eth_type_trans(skb, ks->netdev);
netif_rx(skb);
ks->netdev->stats.rx_packets++;
ks->netdev->stats.rx_bytes += rxlen - 4;
}
ks8851_wrreg16(ks, KS_RXQCR, ks->rc_rxqcr);
}
}
/**
* ks8851_irq_work - work queue handler for dealing with interrupt requests
* @work: The work structure that was scheduled by schedule_work()
*
* This is the handler invoked when the ks8851_irq() is called to find out
* what happened, as we cannot allow ourselves to sleep whilst waiting for
* anything other process has the chip's lock.
*
* Read the interrupt status, work out what needs to be done and then clear
* any of the interrupts that are not needed.
*/
static void ks8851_irq_work(struct work_struct *work)
{
struct ks8851_net *ks = container_of(work, struct ks8851_net, irq_work);
unsigned status;
unsigned handled = 0;
mutex_lock(&ks->lock);
status = ks8851_rdreg16(ks, KS_ISR);
if (netif_msg_intr(ks))
dev_dbg(&ks->spidev->dev, "%s: status 0x%04x\n",
__func__, status);
if (status & IRQ_LCI) {
/* should do something about checking link status */
handled |= IRQ_LCI;
}
if (status & IRQ_LDI) {
u16 pmecr = ks8851_rdreg16(ks, KS_PMECR);
pmecr &= ~PMECR_WKEVT_MASK;
ks8851_wrreg16(ks, KS_PMECR, pmecr | PMECR_WKEVT_LINK);
handled |= IRQ_LDI;
}
if (status & IRQ_RXPSI)
handled |= IRQ_RXPSI;
if (status & IRQ_TXI) {
handled |= IRQ_TXI;
/* no lock here, tx queue should have been stopped */
/* update our idea of how much tx space is available to the
* system */
ks->tx_space = ks8851_rdreg16(ks, KS_TXMIR);
if (netif_msg_intr(ks))
ks_dbg(ks, "%s: txspace %d\n", __func__, ks->tx_space);
}
if (status & IRQ_RXI)
handled |= IRQ_RXI;
if (status & IRQ_SPIBEI) {
dev_err(&ks->spidev->dev, "%s: spi bus error\n", __func__);
handled |= IRQ_SPIBEI;
}
ks8851_wrreg16(ks, KS_ISR, handled);
if (status & IRQ_RXI) {
/* the datasheet says to disable the rx interrupt during
* packet read-out, however we're masking the interrupt
* from the device so do not bother masking just the RX
* from the device. */
ks8851_rx_pkts(ks);
}
/* if something stopped the rx process, probably due to wanting
* to change the rx settings, then do something about restarting
* it. */
if (status & IRQ_RXPSI) {
struct ks8851_rxctrl *rxc = &ks->rxctrl;
/* update the multicast hash table */
ks8851_wrreg16(ks, KS_MAHTR0, rxc->mchash[0]);
ks8851_wrreg16(ks, KS_MAHTR1, rxc->mchash[1]);
ks8851_wrreg16(ks, KS_MAHTR2, rxc->mchash[2]);
ks8851_wrreg16(ks, KS_MAHTR3, rxc->mchash[3]);
ks8851_wrreg16(ks, KS_RXCR2, rxc->rxcr2);
ks8851_wrreg16(ks, KS_RXCR1, rxc->rxcr1);
}
mutex_unlock(&ks->lock);
if (status & IRQ_TXI)
netif_wake_queue(ks->netdev);
enable_irq(ks->netdev->irq);
}
/**
* calc_txlen - calculate size of message to send packet
* @len: Lenght of data
*
* Returns the size of the TXFIFO message needed to send
* this packet.
*/
static inline unsigned calc_txlen(unsigned len)
{
return ALIGN(len + 4, 4);
}
/**
* ks8851_wrpkt - write packet to TX FIFO
* @ks: The device state.
* @txp: The sk_buff to transmit.
* @irq: IRQ on completion of the packet.
*
* Send the @txp to the chip. This means creating the relevant packet header
* specifying the length of the packet and the other information the chip
* needs, such as IRQ on completion. Send the header and the packet data to
* the device.
*/
static void ks8851_wrpkt(struct ks8851_net *ks, struct sk_buff *txp, bool irq)
{
struct spi_transfer *xfer = ks->spi_xfer2;
struct spi_message *msg = &ks->spi_msg2;
unsigned fid = 0;
int ret;
if (netif_msg_tx_queued(ks))
dev_dbg(&ks->spidev->dev, "%s: skb %p, %d@%p, irq %d\n",
__func__, txp, txp->len, txp->data, irq);
fid = ks->fid++;
fid &= TXFR_TXFID_MASK;
if (irq)
fid |= TXFR_TXIC; /* irq on completion */
/* start header at txb[1] to align txw entries */
ks->txh.txb[1] = KS_SPIOP_TXFIFO;
ks->txh.txw[1] = cpu_to_le16(fid);
ks->txh.txw[2] = cpu_to_le16(txp->len);
xfer->tx_buf = &ks->txh.txb[1];
xfer->rx_buf = NULL;
xfer->len = 5;
xfer++;
xfer->tx_buf = txp->data;
xfer->rx_buf = NULL;
xfer->len = ALIGN(txp->len, 4);
ret = spi_sync(ks->spidev, msg);
if (ret < 0)
ks_err(ks, "%s: spi_sync() failed\n", __func__);
}
/**
* ks8851_done_tx - update and then free skbuff after transmitting
* @ks: The device state
* @txb: The buffer transmitted
*/
static void ks8851_done_tx(struct ks8851_net *ks, struct sk_buff *txb)
{
struct net_device *dev = ks->netdev;
dev->stats.tx_bytes += txb->len;
dev->stats.tx_packets++;
dev_kfree_skb(txb);
}
/**
* ks8851_tx_work - process tx packet(s)
* @work: The work strucutre what was scheduled.
*
* This is called when a number of packets have been scheduled for
* transmission and need to be sent to the device.
*/
static void ks8851_tx_work(struct work_struct *work)
{
struct ks8851_net *ks = container_of(work, struct ks8851_net, tx_work);
struct sk_buff *txb;
bool last = skb_queue_empty(&ks->txq);
mutex_lock(&ks->lock);
while (!last) {
txb = skb_dequeue(&ks->txq);
last = skb_queue_empty(&ks->txq);
ks8851_wrreg16(ks, KS_RXQCR, ks->rc_rxqcr | RXQCR_SDA);
ks8851_wrpkt(ks, txb, last);
ks8851_wrreg16(ks, KS_RXQCR, ks->rc_rxqcr);
ks8851_wrreg16(ks, KS_TXQCR, TXQCR_METFE);
ks8851_done_tx(ks, txb);
}
mutex_unlock(&ks->lock);
}
/**
* ks8851_set_powermode - set power mode of the device
* @ks: The device state
* @pwrmode: The power mode value to write to KS_PMECR.
*
* Change the power mode of the chip.
*/
static void ks8851_set_powermode(struct ks8851_net *ks, unsigned pwrmode)
{
unsigned pmecr;
if (netif_msg_hw(ks))
ks_dbg(ks, "setting power mode %d\n", pwrmode);
pmecr = ks8851_rdreg16(ks, KS_PMECR);
pmecr &= ~PMECR_PM_MASK;
pmecr |= pwrmode;
ks8851_wrreg16(ks, KS_PMECR, pmecr);
}
/**
* ks8851_net_open - open network device
* @dev: The network device being opened.
*
* Called when the network device is marked active, such as a user executing
* 'ifconfig up' on the device.
*/
static int ks8851_net_open(struct net_device *dev)
{
struct ks8851_net *ks = netdev_priv(dev);
/* lock the card, even if we may not actually be doing anything
* else at the moment */
mutex_lock(&ks->lock);
if (netif_msg_ifup(ks))
ks_dbg(ks, "opening %s\n", dev->name);
/* bring chip out of any power saving mode it was in */
ks8851_set_powermode(ks, PMECR_PM_NORMAL);
/* issue a soft reset to the RX/TX QMU to put it into a known
* state. */
ks8851_soft_reset(ks, GRR_QMU);
/* setup transmission parameters */
ks8851_wrreg16(ks, KS_TXCR, (TXCR_TXE | /* enable transmit process */
TXCR_TXPE | /* pad to min length */
TXCR_TXCRC | /* add CRC */
TXCR_TXFCE)); /* enable flow control */
/* auto-increment tx data, reset tx pointer */
ks8851_wrreg16(ks, KS_TXFDPR, TXFDPR_TXFPAI);
/* setup receiver control */
ks8851_wrreg16(ks, KS_RXCR1, (RXCR1_RXPAFMA | /* from mac filter */
RXCR1_RXFCE | /* enable flow control */
RXCR1_RXBE | /* broadcast enable */
RXCR1_RXUE | /* unicast enable */
RXCR1_RXE)); /* enable rx block */
/* transfer entire frames out in one go */
ks8851_wrreg16(ks, KS_RXCR2, RXCR2_SRDBL_FRAME);
/* set receive counter timeouts */
ks8851_wrreg16(ks, KS_RXDTTR, 1000); /* 1ms after first frame to IRQ */
ks8851_wrreg16(ks, KS_RXDBCTR, 4096); /* >4Kbytes in buffer to IRQ */
ks8851_wrreg16(ks, KS_RXFCTR, 10); /* 10 frames to IRQ */
ks->rc_rxqcr = (RXQCR_RXFCTE | /* IRQ on frame count exceeded */
RXQCR_RXDBCTE | /* IRQ on byte count exceeded */
RXQCR_RXDTTE); /* IRQ on time exceeded */
ks8851_wrreg16(ks, KS_RXQCR, ks->rc_rxqcr);
/* clear then enable interrupts */
#define STD_IRQ (IRQ_LCI | /* Link Change */ \
IRQ_TXI | /* TX done */ \
IRQ_RXI | /* RX done */ \
IRQ_SPIBEI | /* SPI bus error */ \
IRQ_TXPSI | /* TX process stop */ \
IRQ_RXPSI) /* RX process stop */
ks->rc_ier = STD_IRQ;
ks8851_wrreg16(ks, KS_ISR, STD_IRQ);
ks8851_wrreg16(ks, KS_IER, STD_IRQ);
netif_start_queue(ks->netdev);
if (netif_msg_ifup(ks))
ks_dbg(ks, "network device %s up\n", dev->name);
mutex_unlock(&ks->lock);
return 0;
}
/**
* ks8851_net_stop - close network device
* @dev: The device being closed.
*
* Called to close down a network device which has been active. Cancell any
* work, shutdown the RX and TX process and then place the chip into a low
* power state whilst it is not being used.
*/
static int ks8851_net_stop(struct net_device *dev)
{
struct ks8851_net *ks = netdev_priv(dev);
if (netif_msg_ifdown(ks))
ks_info(ks, "%s: shutting down\n", dev->name);
netif_stop_queue(dev);
mutex_lock(&ks->lock);
/* stop any outstanding work */
flush_work(&ks->irq_work);
flush_work(&ks->tx_work);
flush_work(&ks->rxctrl_work);
/* turn off the IRQs and ack any outstanding */
ks8851_wrreg16(ks, KS_IER, 0x0000);
ks8851_wrreg16(ks, KS_ISR, 0xffff);
/* shutdown RX process */
ks8851_wrreg16(ks, KS_RXCR1, 0x0000);
/* shutdown TX process */
ks8851_wrreg16(ks, KS_TXCR, 0x0000);
/* set powermode to soft power down to save power */
ks8851_set_powermode(ks, PMECR_PM_SOFTDOWN);
/* ensure any queued tx buffers are dumped */
while (!skb_queue_empty(&ks->txq)) {
struct sk_buff *txb = skb_dequeue(&ks->txq);
if (netif_msg_ifdown(ks))
ks_dbg(ks, "%s: freeing txb %p\n", __func__, txb);
dev_kfree_skb(txb);
}
mutex_unlock(&ks->lock);
return 0;
}
/**
* ks8851_start_xmit - transmit packet
* @skb: The buffer to transmit
* @dev: The device used to transmit the packet.
*
* Called by the network layer to transmit the @skb. Queue the packet for
* the device and schedule the necessary work to transmit the packet when
* it is free.
*
* We do this to firstly avoid sleeping with the network device locked,
* and secondly so we can round up more than one packet to transmit which
* means we can try and avoid generating too many transmit done interrupts.
*/
static netdev_tx_t ks8851_start_xmit(struct sk_buff *skb,
struct net_device *dev)
{
struct ks8851_net *ks = netdev_priv(dev);
unsigned needed = calc_txlen(skb->len);
netdev_tx_t ret = NETDEV_TX_OK;
if (netif_msg_tx_queued(ks))
ks_dbg(ks, "%s: skb %p, %d@%p\n", __func__,
skb, skb->len, skb->data);
spin_lock(&ks->statelock);
if (needed > ks->tx_space) {
netif_stop_queue(dev);
ret = NETDEV_TX_BUSY;
} else {
ks->tx_space -= needed;
skb_queue_tail(&ks->txq, skb);
}
spin_unlock(&ks->statelock);
schedule_work(&ks->tx_work);
return ret;
}
/**
* ks8851_rxctrl_work - work handler to change rx mode
* @work: The work structure this belongs to.
*
* Lock the device and issue the necessary changes to the receive mode from
* the network device layer. This is done so that we can do this without
* having to sleep whilst holding the network device lock.
*
* Since the recommendation from Micrel is that the RXQ is shutdown whilst the
* receive parameters are programmed, we issue a write to disable the RXQ and
* then wait for the interrupt handler to be triggered once the RXQ shutdown is
* complete. The interrupt handler then writes the new values into the chip.
*/
static void ks8851_rxctrl_work(struct work_struct *work)
{
struct ks8851_net *ks = container_of(work, struct ks8851_net, rxctrl_work);
mutex_lock(&ks->lock);
/* need to shutdown RXQ before modifying filter parameters */
ks8851_wrreg16(ks, KS_RXCR1, 0x00);
mutex_unlock(&ks->lock);
}
static void ks8851_set_rx_mode(struct net_device *dev)
{
struct ks8851_net *ks = netdev_priv(dev);
struct ks8851_rxctrl rxctrl;
memset(&rxctrl, 0, sizeof(rxctrl));
if (dev->flags & IFF_PROMISC) {
/* interface to receive everything */
rxctrl.rxcr1 = RXCR1_RXAE | RXCR1_RXINVF;
} else if (dev->flags & IFF_ALLMULTI) {
/* accept all multicast packets */
rxctrl.rxcr1 = (RXCR1_RXME | RXCR1_RXAE |
RXCR1_RXPAFMA | RXCR1_RXMAFMA);
} else if (dev->flags & IFF_MULTICAST && dev->mc_count > 0) {
struct dev_mc_list *mcptr = dev->mc_list;
u32 crc;
int i;
/* accept some multicast */
for (i = dev->mc_count; i > 0; i--) {
crc = ether_crc(ETH_ALEN, mcptr->dmi_addr);
crc >>= (32 - 6); /* get top six bits */
rxctrl.mchash[crc >> 4] |= (1 << (crc & 0xf));
mcptr = mcptr->next;
}
rxctrl.rxcr1 = RXCR1_RXME | RXCR1_RXPAFMA;
} else {
/* just accept broadcast / unicast */
rxctrl.rxcr1 = RXCR1_RXPAFMA;
}
rxctrl.rxcr1 |= (RXCR1_RXUE | /* unicast enable */
RXCR1_RXBE | /* broadcast enable */
RXCR1_RXE | /* RX process enable */
RXCR1_RXFCE); /* enable flow control */
rxctrl.rxcr2 |= RXCR2_SRDBL_FRAME;
/* schedule work to do the actual set of the data if needed */
spin_lock(&ks->statelock);
if (memcmp(&rxctrl, &ks->rxctrl, sizeof(rxctrl)) != 0) {
memcpy(&ks->rxctrl, &rxctrl, sizeof(ks->rxctrl));
schedule_work(&ks->rxctrl_work);
}
spin_unlock(&ks->statelock);
}
static int ks8851_set_mac_address(struct net_device *dev, void *addr)
{
struct sockaddr *sa = addr;
if (netif_running(dev))
return -EBUSY;
if (!is_valid_ether_addr(sa->sa_data))
return -EADDRNOTAVAIL;
memcpy(dev->dev_addr, sa->sa_data, ETH_ALEN);
return ks8851_write_mac_addr(dev);
}
static int ks8851_net_ioctl(struct net_device *dev, struct ifreq *req, int cmd)
{
struct ks8851_net *ks = netdev_priv(dev);
if (!netif_running(dev))
return -EINVAL;
return generic_mii_ioctl(&ks->mii, if_mii(req), cmd, NULL);
}
static const struct net_device_ops ks8851_netdev_ops = {
.ndo_open = ks8851_net_open,
.ndo_stop = ks8851_net_stop,
.ndo_do_ioctl = ks8851_net_ioctl,
.ndo_start_xmit = ks8851_start_xmit,
.ndo_set_mac_address = ks8851_set_mac_address,
.ndo_set_rx_mode = ks8851_set_rx_mode,
.ndo_change_mtu = eth_change_mtu,
.ndo_validate_addr = eth_validate_addr,
};
/* ethtool support */
static void ks8851_get_drvinfo(struct net_device *dev,
struct ethtool_drvinfo *di)
{
strlcpy(di->driver, "KS8851", sizeof(di->driver));
strlcpy(di->version, "1.00", sizeof(di->version));
strlcpy(di->bus_info, dev_name(dev->dev.parent), sizeof(di->bus_info));
}
static u32 ks8851_get_msglevel(struct net_device *dev)
{
struct ks8851_net *ks = netdev_priv(dev);
return ks->msg_enable;
}
static void ks8851_set_msglevel(struct net_device *dev, u32 to)
{
struct ks8851_net *ks = netdev_priv(dev);
ks->msg_enable = to;
}
static int ks8851_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
struct ks8851_net *ks = netdev_priv(dev);
return mii_ethtool_gset(&ks->mii, cmd);
}
static int ks8851_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
struct ks8851_net *ks = netdev_priv(dev);
return mii_ethtool_sset(&ks->mii, cmd);
}
static u32 ks8851_get_link(struct net_device *dev)
{
struct ks8851_net *ks = netdev_priv(dev);
return mii_link_ok(&ks->mii);
}
static int ks8851_nway_reset(struct net_device *dev)
{
struct ks8851_net *ks = netdev_priv(dev);
return mii_nway_restart(&ks->mii);
}
static const struct ethtool_ops ks8851_ethtool_ops = {
.get_drvinfo = ks8851_get_drvinfo,
.get_msglevel = ks8851_get_msglevel,
.set_msglevel = ks8851_set_msglevel,
.get_settings = ks8851_get_settings,
.set_settings = ks8851_set_settings,
.get_link = ks8851_get_link,
.nway_reset = ks8851_nway_reset,
};
/* MII interface controls */
/**
* ks8851_phy_reg - convert MII register into a KS8851 register
* @reg: MII register number.
*
* Return the KS8851 register number for the corresponding MII PHY register
* if possible. Return zero if the MII register has no direct mapping to the
* KS8851 register set.
*/
static int ks8851_phy_reg(int reg)
{
switch (reg) {
case MII_BMCR:
return KS_P1MBCR;
case MII_BMSR:
return KS_P1MBSR;
case MII_PHYSID1:
return KS_PHY1ILR;
case MII_PHYSID2:
return KS_PHY1IHR;
case MII_ADVERTISE:
return KS_P1ANAR;
case MII_LPA:
return KS_P1ANLPR;
}
return 0x0;
}
/**
* ks8851_phy_read - MII interface PHY register read.
* @dev: The network device the PHY is on.
* @phy_addr: Address of PHY (ignored as we only have one)
* @reg: The register to read.
*
* This call reads data from the PHY register specified in @reg. Since the
* device does not support all the MII registers, the non-existant values
* are always returned as zero.
*
* We return zero for unsupported registers as the MII code does not check
* the value returned for any error status, and simply returns it to the
* caller. The mii-tool that the driver was tested with takes any -ve error
* as real PHY capabilities, thus displaying incorrect data to the user.
*/
static int ks8851_phy_read(struct net_device *dev, int phy_addr, int reg)
{
struct ks8851_net *ks = netdev_priv(dev);
int ksreg;
int result;
ksreg = ks8851_phy_reg(reg);
if (!ksreg)
return 0x0; /* no error return allowed, so use zero */
mutex_lock(&ks->lock);
result = ks8851_rdreg16(ks, ksreg);
mutex_unlock(&ks->lock);
return result;
}
static void ks8851_phy_write(struct net_device *dev,
int phy, int reg, int value)
{
struct ks8851_net *ks = netdev_priv(dev);
int ksreg;
ksreg = ks8851_phy_reg(reg);
if (ksreg) {
mutex_lock(&ks->lock);
ks8851_wrreg16(ks, ksreg, value);
mutex_unlock(&ks->lock);
}
}
/**
* ks8851_read_selftest - read the selftest memory info.
* @ks: The device state
*
* Read and check the TX/RX memory selftest information.
*/
static int ks8851_read_selftest(struct ks8851_net *ks)
{
unsigned both_done = MBIR_TXMBF | MBIR_RXMBF;
int ret = 0;
unsigned rd;
rd = ks8851_rdreg16(ks, KS_MBIR);
if ((rd & both_done) != both_done) {
ks_warn(ks, "Memory selftest not finished\n");
return 0;
}
if (rd & MBIR_TXMBFA) {
ks_err(ks, "TX memory selftest fail\n");
ret |= 1;
}
if (rd & MBIR_RXMBFA) {
ks_err(ks, "RX memory selftest fail\n");
ret |= 2;
}
return 0;
}
/* driver bus management functions */
static int __devinit ks8851_probe(struct spi_device *spi)
{
struct net_device *ndev;
struct ks8851_net *ks;
int ret;
ndev = alloc_etherdev(sizeof(struct ks8851_net));
if (!ndev) {
dev_err(&spi->dev, "failed to alloc ethernet device\n");
return -ENOMEM;
}
spi->bits_per_word = 8;
ks = netdev_priv(ndev);
ks->netdev = ndev;
ks->spidev = spi;
ks->tx_space = 6144;
mutex_init(&ks->lock);
spin_lock_init(&ks->statelock);
INIT_WORK(&ks->tx_work, ks8851_tx_work);
INIT_WORK(&ks->irq_work, ks8851_irq_work);
INIT_WORK(&ks->rxctrl_work, ks8851_rxctrl_work);
/* initialise pre-made spi transfer messages */
spi_message_init(&ks->spi_msg1);
spi_message_add_tail(&ks->spi_xfer1, &ks->spi_msg1);
spi_message_init(&ks->spi_msg2);
spi_message_add_tail(&ks->spi_xfer2[0], &ks->spi_msg2);
spi_message_add_tail(&ks->spi_xfer2[1], &ks->spi_msg2);
/* setup mii state */
ks->mii.dev = ndev;
ks->mii.phy_id = 1,
ks->mii.phy_id_mask = 1;
ks->mii.reg_num_mask = 0xf;
ks->mii.mdio_read = ks8851_phy_read;
ks->mii.mdio_write = ks8851_phy_write;
dev_info(&spi->dev, "message enable is %d\n", msg_enable);
/* set the default message enable */
ks->msg_enable = netif_msg_init(msg_enable, (NETIF_MSG_DRV |
NETIF_MSG_PROBE |
NETIF_MSG_LINK));
skb_queue_head_init(&ks->txq);
SET_ETHTOOL_OPS(ndev, &ks8851_ethtool_ops);
SET_NETDEV_DEV(ndev, &spi->dev);
dev_set_drvdata(&spi->dev, ks);
ndev->if_port = IF_PORT_100BASET;
ndev->netdev_ops = &ks8851_netdev_ops;
ndev->irq = spi->irq;
/* issue a global soft reset to reset the device. */
ks8851_soft_reset(ks, GRR_GSR);
/* simple check for a valid chip being connected to the bus */
if ((ks8851_rdreg16(ks, KS_CIDER) & ~CIDER_REV_MASK) != CIDER_ID) {
dev_err(&spi->dev, "failed to read device ID\n");
ret = -ENODEV;
goto err_id;
}
ks8851_read_selftest(ks);
ks8851_init_mac(ks);
ret = request_irq(spi->irq, ks8851_irq, IRQF_TRIGGER_LOW,
ndev->name, ks);
if (ret < 0) {
dev_err(&spi->dev, "failed to get irq\n");
goto err_irq;
}
ret = register_netdev(ndev);
if (ret) {
dev_err(&spi->dev, "failed to register network device\n");
goto err_netdev;
}
dev_info(&spi->dev, "revision %d, MAC %pM, IRQ %d\n",
CIDER_REV_GET(ks8851_rdreg16(ks, KS_CIDER)),
ndev->dev_addr, ndev->irq);
return 0;
err_netdev:
free_irq(ndev->irq, ndev);
err_id:
err_irq:
free_netdev(ndev);
return ret;
}
static int __devexit ks8851_remove(struct spi_device *spi)
{
struct ks8851_net *priv = dev_get_drvdata(&spi->dev);
if (netif_msg_drv(priv))
dev_info(&spi->dev, "remove");
unregister_netdev(priv->netdev);
free_irq(spi->irq, priv);
free_netdev(priv->netdev);
return 0;
}
static struct spi_driver ks8851_driver = {
.driver = {
.name = "ks8851",
.owner = THIS_MODULE,
},
.probe = ks8851_probe,
.remove = __devexit_p(ks8851_remove),
};
static int __init ks8851_init(void)
{
return spi_register_driver(&ks8851_driver);
}
static void __exit ks8851_exit(void)
{
spi_unregister_driver(&ks8851_driver);
}
module_init(ks8851_init);
module_exit(ks8851_exit);
MODULE_DESCRIPTION("KS8851 Network driver");
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_LICENSE("GPL");
module_param_named(message, msg_enable, int, 0);
MODULE_PARM_DESC(message, "Message verbosity level (0=none, 31=all)");
MODULE_ALIAS("spi:ks8851");