/******************************************************************* 
 * ident "$Id: idt77252.c,v 1.2 2001/11/11 08:13:54 ecd Exp $"
 *
 * $Author: ecd $
 * $Date: 2001/11/11 08:13:54 $
 *
 * Copyright (c) 2000 ATecoM GmbH 
 *
 * The author may be reached at ecd@atecom.com.
 *
 * 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.
 *
 * THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR   IMPLIED
 * WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
 * NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT,  INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
 * USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * You should have received a copy of the  GNU General Public License along
 * with this program; if not, write  to the Free Software Foundation, Inc.,
 * 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *******************************************************************/
static char const rcsid[] =
"$Id: idt77252.c,v 1.2 2001/11/11 08:13:54 ecd Exp $";


#include <linux/module.h>
#include <linux/config.h>
#include <linux/pci.h>
#include <linux/skbuff.h>
#include <linux/kernel.h>
#include <linux/vmalloc.h>
#include <linux/netdevice.h>
#include <linux/atmdev.h>
#include <linux/atm.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/wait.h>
#include <asm/semaphore.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/atomic.h>
#include <asm/byteorder.h>

#ifdef CONFIG_ATM_IDT77252_USE_SUNI
#include "suni.h"
#endif /* CONFIG_ATM_IDT77252_USE_SUNI */


#include "idt77252.h"
#include "idt77252_tables.h"

static unsigned int vpibits = 1;


#define CONFIG_ATM_IDT77252_SEND_IDLE 1


/*
 * Debug HACKs.
 */
#define DEBUG_MODULE 1
#undef HAVE_EEPROM	/* does not work, yet. */

#ifdef CONFIG_ATM_IDT77252_DEBUG
static unsigned long debug = DBG_GENERAL;
#endif


#define SAR_RX_DELAY	(SAR_CFG_RXINT_NODELAY)


/*
 * SCQ Handling.
 */
static struct scq_info *alloc_scq(struct idt77252_dev *, int);
static void free_scq(struct idt77252_dev *, struct scq_info *);
static int queue_skb(struct idt77252_dev *, struct vc_map *,
		     struct sk_buff *, int oam);
static void drain_scq(struct idt77252_dev *, struct vc_map *);
static unsigned long get_free_scd(struct idt77252_dev *, struct vc_map *);
static void fill_scd(struct idt77252_dev *, struct scq_info *, int);

/*
 * FBQ Handling.
 */
static int push_rx_skb(struct idt77252_dev *,
		       struct sk_buff *, int queue);
static void recycle_rx_skb(struct idt77252_dev *, struct sk_buff *);
static void flush_rx_pool(struct idt77252_dev *, struct rx_pool *);
static void recycle_rx_pool_skb(struct idt77252_dev *,
				struct rx_pool *);
static void add_rx_skb(struct idt77252_dev *, int queue,
		       unsigned int size, unsigned int count);

/*
 * RSQ Handling.
 */
static int init_rsq(struct idt77252_dev *);
static void deinit_rsq(struct idt77252_dev *);
static void idt77252_rx(struct idt77252_dev *);

/*
 * TSQ handling.
 */
static int init_tsq(struct idt77252_dev *);
static void deinit_tsq(struct idt77252_dev *);
static void idt77252_tx(struct idt77252_dev *);


/*
 * ATM Interface.
 */
static void idt77252_dev_close(struct atm_dev *dev);
static int idt77252_open(struct atm_vcc *vcc);
static void idt77252_close(struct atm_vcc *vcc);
static int idt77252_send(struct atm_vcc *vcc, struct sk_buff *skb);
static int idt77252_send_oam(struct atm_vcc *vcc, void *cell,
			     int flags);
static void idt77252_phy_put(struct atm_dev *dev, unsigned char value,
			     unsigned long addr);
static unsigned char idt77252_phy_get(struct atm_dev *dev, unsigned long addr);
static int idt77252_change_qos(struct atm_vcc *vcc, struct atm_qos *qos,
			       int flags);
static int idt77252_proc_read(struct atm_dev *dev, loff_t * pos,
			      char *page);
static void idt77252_softint(void *dev_id);


static struct atmdev_ops idt77252_ops =
{
	.dev_close	= idt77252_dev_close,
	.open		= idt77252_open,
	.close		= idt77252_close,
	.send		= idt77252_send,
	.send_oam	= idt77252_send_oam,
	.phy_put	= idt77252_phy_put,
	.phy_get	= idt77252_phy_get,
	.change_qos	= idt77252_change_qos,
	.proc_read	= idt77252_proc_read,
	.owner		= THIS_MODULE
};

static struct idt77252_dev *idt77252_chain = NULL;
static unsigned int idt77252_sram_write_errors = 0;

/*****************************************************************************/
/*                                                                           */
/* I/O and Utility Bus                                                       */
/*                                                                           */
/*****************************************************************************/

static void
waitfor_idle(struct idt77252_dev *card)
{
	u32 stat;

	stat = readl(SAR_REG_STAT);
	while (stat & SAR_STAT_CMDBZ)
		stat = readl(SAR_REG_STAT);
}

static u32
read_sram(struct idt77252_dev *card, unsigned long addr)
{
	unsigned long flags;
	u32 value;

	spin_lock_irqsave(&card->cmd_lock, flags);
	writel(SAR_CMD_READ_SRAM | (addr << 2), SAR_REG_CMD);
	waitfor_idle(card);
	value = readl(SAR_REG_DR0);
	spin_unlock_irqrestore(&card->cmd_lock, flags);
	return value;
}

static void
write_sram(struct idt77252_dev *card, unsigned long addr, u32 value)
{
	unsigned long flags;

	if ((idt77252_sram_write_errors == 0) &&
	    (((addr > card->tst[0] + card->tst_size - 2) &&
	      (addr < card->tst[0] + card->tst_size)) ||
	     ((addr > card->tst[1] + card->tst_size - 2) &&
	      (addr < card->tst[1] + card->tst_size)))) {
		printk("%s: ERROR: TST JMP section at %08lx written: %08x\n",
		       card->name, addr, value);
	}

	spin_lock_irqsave(&card->cmd_lock, flags);
	writel(value, SAR_REG_DR0);
	writel(SAR_CMD_WRITE_SRAM | (addr << 2), SAR_REG_CMD);
	waitfor_idle(card);
	spin_unlock_irqrestore(&card->cmd_lock, flags);
}

static u8
read_utility(void *dev, unsigned long ubus_addr)
{
	struct idt77252_dev *card = dev;
	unsigned long flags;
	u8 value;

	if (!card) {
		printk("Error: No such device.\n");
		return -1;
	}

	spin_lock_irqsave(&card->cmd_lock, flags);
	writel(SAR_CMD_READ_UTILITY + ubus_addr, SAR_REG_CMD);
	waitfor_idle(card);
	value = readl(SAR_REG_DR0);
	spin_unlock_irqrestore(&card->cmd_lock, flags);
	return value;
}

static void
write_utility(void *dev, unsigned long ubus_addr, u8 value)
{
	struct idt77252_dev *card = dev;
	unsigned long flags;

	if (!card) {
		printk("Error: No such device.\n");
		return;
	}

	spin_lock_irqsave(&card->cmd_lock, flags);
	writel((u32) value, SAR_REG_DR0);
	writel(SAR_CMD_WRITE_UTILITY + ubus_addr, SAR_REG_CMD);
	waitfor_idle(card);
	spin_unlock_irqrestore(&card->cmd_lock, flags);
}

#ifdef HAVE_EEPROM
static u32 rdsrtab[] =
{
	SAR_GP_EECS | SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	SAR_GP_EEDO,
	SAR_GP_EESCLK | SAR_GP_EEDO,	/* 1 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	SAR_GP_EEDO,
	SAR_GP_EESCLK | SAR_GP_EEDO	/* 1 */
};

static u32 wrentab[] =
{
	SAR_GP_EECS | SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	SAR_GP_EEDO,
	SAR_GP_EESCLK | SAR_GP_EEDO,	/* 1 */
	SAR_GP_EEDO,
	SAR_GP_EESCLK | SAR_GP_EEDO,	/* 1 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK			/* 0 */
};

static u32 rdtab[] =
{
	SAR_GP_EECS | SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	SAR_GP_EEDO,
	SAR_GP_EESCLK | SAR_GP_EEDO,	/* 1 */
	SAR_GP_EEDO,
	SAR_GP_EESCLK | SAR_GP_EEDO	/* 1 */
};

static u32 wrtab[] =
{
	SAR_GP_EECS | SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	0,
	SAR_GP_EESCLK,			/* 0 */
	SAR_GP_EEDO,
	SAR_GP_EESCLK | SAR_GP_EEDO,	/* 1 */
	0,
	SAR_GP_EESCLK			/* 0 */
};

static u32 clktab[] =
{
	0,
	SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,
	0,
	SAR_GP_EESCLK,
	0
};

static u32
idt77252_read_gp(struct idt77252_dev *card)
{
	u32 gp;

	gp = readl(SAR_REG_GP);
#if 0
	printk("RD: %s\n", gp & SAR_GP_EEDI ? "1" : "0");
#endif
	return gp;
}

static void
idt77252_write_gp(struct idt77252_dev *card, u32 value)
{
	unsigned long flags;

#if 0
	printk("WR: %s %s %s\n", value & SAR_GP_EECS ? "   " : "/CS",
	       value & SAR_GP_EESCLK ? "HIGH" : "LOW ",
	       value & SAR_GP_EEDO   ? "1" : "0");
#endif

	spin_lock_irqsave(&card->cmd_lock, flags);
	waitfor_idle(card);
	writel(value, SAR_REG_GP);
	spin_unlock_irqrestore(&card->cmd_lock, flags);
}

static u8
idt77252_eeprom_read_status(struct idt77252_dev *card)
{
	u8 byte;
	u32 gp;
	int i, j;

	gp = idt77252_read_gp(card) & ~(SAR_GP_EESCLK|SAR_GP_EECS|SAR_GP_EEDO);

	for (i = 0; i < sizeof(rdsrtab)/sizeof(rdsrtab[0]); i++) {
		idt77252_write_gp(card, gp | rdsrtab[i]);
		udelay(5);
	}
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);

	byte = 0;
	for (i = 0, j = 0; i < 8; i++) {
		byte <<= 1;

		idt77252_write_gp(card, gp | clktab[j++]);
		udelay(5);

		byte |= idt77252_read_gp(card) & SAR_GP_EEDI ? 1 : 0;

		idt77252_write_gp(card, gp | clktab[j++]);
		udelay(5);
	}
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);

	return byte;
}

static u8
idt77252_eeprom_read_byte(struct idt77252_dev *card, u8 offset)
{
	u8 byte;
	u32 gp;
	int i, j;

	gp = idt77252_read_gp(card) & ~(SAR_GP_EESCLK|SAR_GP_EECS|SAR_GP_EEDO);

	for (i = 0; i < sizeof(rdtab)/sizeof(rdtab[0]); i++) {
		idt77252_write_gp(card, gp | rdtab[i]);
		udelay(5);
	}
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);

	for (i = 0, j = 0; i < 8; i++) {
		idt77252_write_gp(card, gp | clktab[j++] |
					(offset & 1 ? SAR_GP_EEDO : 0));
		udelay(5);

		idt77252_write_gp(card, gp | clktab[j++] |
					(offset & 1 ? SAR_GP_EEDO : 0));
		udelay(5);

		offset >>= 1;
	}
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);

	byte = 0;
	for (i = 0, j = 0; i < 8; i++) {
		byte <<= 1;

		idt77252_write_gp(card, gp | clktab[j++]);
		udelay(5);

		byte |= idt77252_read_gp(card) & SAR_GP_EEDI ? 1 : 0;

		idt77252_write_gp(card, gp | clktab[j++]);
		udelay(5);
	}
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);

	return byte;
}

static void
idt77252_eeprom_write_byte(struct idt77252_dev *card, u8 offset, u8 data)
{
	u32 gp;
	int i, j;

	gp = idt77252_read_gp(card) & ~(SAR_GP_EESCLK|SAR_GP_EECS|SAR_GP_EEDO);

	for (i = 0; i < sizeof(wrentab)/sizeof(wrentab[0]); i++) {
		idt77252_write_gp(card, gp | wrentab[i]);
		udelay(5);
	}
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);

	for (i = 0; i < sizeof(wrtab)/sizeof(wrtab[0]); i++) {
		idt77252_write_gp(card, gp | wrtab[i]);
		udelay(5);
	}
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);

	for (i = 0, j = 0; i < 8; i++) {
		idt77252_write_gp(card, gp | clktab[j++] |
					(offset & 1 ? SAR_GP_EEDO : 0));
		udelay(5);

		idt77252_write_gp(card, gp | clktab[j++] |
					(offset & 1 ? SAR_GP_EEDO : 0));
		udelay(5);

		offset >>= 1;
	}
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);

	for (i = 0, j = 0; i < 8; i++) {
		idt77252_write_gp(card, gp | clktab[j++] |
					(data & 1 ? SAR_GP_EEDO : 0));
		udelay(5);

		idt77252_write_gp(card, gp | clktab[j++] |
					(data & 1 ? SAR_GP_EEDO : 0));
		udelay(5);

		data >>= 1;
	}
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);
}

static void
idt77252_eeprom_init(struct idt77252_dev *card)
{
	u32 gp;

	gp = idt77252_read_gp(card) & ~(SAR_GP_EESCLK|SAR_GP_EECS|SAR_GP_EEDO);

	idt77252_write_gp(card, gp | SAR_GP_EECS | SAR_GP_EESCLK);
	udelay(5);
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);
	idt77252_write_gp(card, gp | SAR_GP_EECS | SAR_GP_EESCLK);
	udelay(5);
	idt77252_write_gp(card, gp | SAR_GP_EECS);
	udelay(5);
}
#endif /* HAVE_EEPROM */


#ifdef CONFIG_ATM_IDT77252_DEBUG
static void
dump_tct(struct idt77252_dev *card, int index)
{
	unsigned long tct;
	int i;

	tct = (unsigned long) (card->tct_base + index * SAR_SRAM_TCT_SIZE);

	printk("%s: TCT %x:", card->name, index);
	for (i = 0; i < 8; i++) {
		printk(" %08x", read_sram(card, tct + i));
	}
	printk("\n");
}

static void
idt77252_tx_dump(struct idt77252_dev *card)
{
	struct atm_vcc *vcc;
	struct vc_map *vc;
	int i;

	printk("%s\n", __FUNCTION__);
	for (i = 0; i < card->tct_size; i++) {
		vc = card->vcs[i];
		if (!vc)
			continue;

		vcc = NULL;
		if (vc->rx_vcc)
			vcc = vc->rx_vcc;
		else if (vc->tx_vcc)
			vcc = vc->tx_vcc;

		if (!vcc)
			continue;

		printk("%s: Connection %d:\n", card->name, vc->index);
		dump_tct(card, vc->index);
	}
}
#endif


/*****************************************************************************/
/*                                                                           */
/* SCQ Handling                                                              */
/*                                                                           */
/*****************************************************************************/

static int
sb_pool_add(struct idt77252_dev *card, struct sk_buff *skb, int queue)
{
	struct sb_pool *pool = &card->sbpool[queue];
	int index;

	index = pool->index;
	while (pool->skb[index]) {
		index = (index + 1) & FBQ_MASK;
		if (index == pool->index)
			return -ENOBUFS;
	}

	pool->skb[index] = skb;
	IDT77252_PRV_POOL(skb) = POOL_HANDLE(queue, index);

	pool->index = (index + 1) & FBQ_MASK;
	return 0;
}

static void
sb_pool_remove(struct idt77252_dev *card, struct sk_buff *skb)
{
	unsigned int queue, index;
	u32 handle;

	handle = IDT77252_PRV_POOL(skb);

	queue = POOL_QUEUE(handle);
	if (queue > 3)
		return;

	index = POOL_INDEX(handle);
	if (index > FBQ_SIZE - 1)
		return;

	card->sbpool[queue].skb[index] = NULL;
}

static struct sk_buff *
sb_pool_skb(struct idt77252_dev *card, u32 handle)
{
	unsigned int queue, index;

	queue = POOL_QUEUE(handle);
	if (queue > 3)
		return NULL;

	index = POOL_INDEX(handle);
	if (index > FBQ_SIZE - 1)
		return NULL;

	return card->sbpool[queue].skb[index];
}

static struct scq_info *
alloc_scq(struct idt77252_dev *card, int class)
{
	struct scq_info *scq;

	scq = (struct scq_info *) kmalloc(sizeof(struct scq_info), GFP_KERNEL);
	if (!scq)
		return NULL;
	memset(scq, 0, sizeof(struct scq_info));

	scq->base = pci_alloc_consistent(card->pcidev, SCQ_SIZE,
					 &scq->paddr);
	if (scq->base == NULL) {
		kfree(scq);
		return NULL;
	}
	memset(scq->base, 0, SCQ_SIZE);

	scq->next = scq->base;
	scq->last = scq->base + (SCQ_ENTRIES - 1);
	atomic_set(&scq->used, 0);

	spin_lock_init(&scq->lock);
	spin_lock_init(&scq->skblock);

	skb_queue_head_init(&scq->transmit);
	skb_queue_head_init(&scq->pending);

	TXPRINTK("idt77252: SCQ: base 0x%p, next 0x%p, last 0x%p, paddr %08llx\n",
		 scq->base, scq->next, scq->last, (unsigned long long)scq->paddr);

	return scq;
}

static void
free_scq(struct idt77252_dev *card, struct scq_info *scq)
{
	struct sk_buff *skb;
	struct atm_vcc *vcc;

	pci_free_consistent(card->pcidev, SCQ_SIZE,
			    scq->base, scq->paddr);

	while ((skb = skb_dequeue(&scq->transmit))) {
		pci_unmap_single(card->pcidev, IDT77252_PRV_PADDR(skb),
				 skb->len, PCI_DMA_TODEVICE);

		vcc = ATM_SKB(skb)->vcc;
		if (vcc->pop)
			vcc->pop(vcc, skb);
		else
			dev_kfree_skb(skb);
	}

	while ((skb = skb_dequeue(&scq->pending))) {
		pci_unmap_single(card->pcidev, IDT77252_PRV_PADDR(skb),
				 skb->len, PCI_DMA_TODEVICE);

		vcc = ATM_SKB(skb)->vcc;
		if (vcc->pop)
			vcc->pop(vcc, skb);
		else
			dev_kfree_skb(skb);
	}

	kfree(scq);
}


static int
push_on_scq(struct idt77252_dev *card, struct vc_map *vc, struct sk_buff *skb)
{
	struct scq_info *scq = vc->scq;
	unsigned long flags;
	struct scqe *tbd;
	int entries;

	TXPRINTK("%s: SCQ: next 0x%p\n", card->name, scq->next);

	atomic_inc(&scq->used);
	entries = atomic_read(&scq->used);
	if (entries > (SCQ_ENTRIES - 1)) {
		atomic_dec(&scq->used);
		goto out;
	}

	skb_queue_tail(&scq->transmit, skb);

	spin_lock_irqsave(&vc->lock, flags);
	if (vc->estimator) {
		struct atm_vcc *vcc = vc->tx_vcc;
		struct sock *sk = sk_atm(vcc);

		vc->estimator->cells += (skb->len + 47) / 48;
		if (atomic_read(&sk->sk_wmem_alloc) >
		    (sk->sk_sndbuf >> 1)) {
			u32 cps = vc->estimator->maxcps;

			vc->estimator->cps = cps;
			vc->estimator->avcps = cps << 5;
			if (vc->lacr < vc->init_er) {
				vc->lacr = vc->init_er;
				writel(TCMDQ_LACR | (vc->lacr << 16) |
				       vc->index, SAR_REG_TCMDQ);
			}
		}
	}
	spin_unlock_irqrestore(&vc->lock, flags);

	tbd = &IDT77252_PRV_TBD(skb);

	spin_lock_irqsave(&scq->lock, flags);
	scq->next->word_1 = cpu_to_le32(tbd->word_1 |
					SAR_TBD_TSIF | SAR_TBD_GTSI);
	scq->next->word_2 = cpu_to_le32(tbd->word_2);
	scq->next->word_3 = cpu_to_le32(tbd->word_3);
	scq->next->word_4 = cpu_to_le32(tbd->word_4);

	if (scq->next == scq->last)
		scq->next = scq->base;
	else
		scq->next++;

	write_sram(card, scq->scd,
		   scq->paddr +
		   (u32)((unsigned long)scq->next - (unsigned long)scq->base));
	spin_unlock_irqrestore(&scq->lock, flags);

	scq->trans_start = jiffies;

	if (test_and_clear_bit(VCF_IDLE, &vc->flags)) {
		writel(TCMDQ_START_LACR | (vc->lacr << 16) | vc->index,
		       SAR_REG_TCMDQ);
	}

	TXPRINTK("%d entries in SCQ used (push).\n", atomic_read(&scq->used));

	XPRINTK("%s: SCQ (after push %2d) head = 0x%x, next = 0x%p.\n",
		card->name, atomic_read(&scq->used),
		read_sram(card, scq->scd + 1), scq->next);

	return 0;

out:
	if (jiffies - scq->trans_start > HZ) {
		printk("%s: Error pushing TBD for %d.%d\n",
		       card->name, vc->tx_vcc->vpi, vc->tx_vcc->vci);
#ifdef CONFIG_ATM_IDT77252_DEBUG
		idt77252_tx_dump(card);
#endif
		scq->trans_start = jiffies;
	}

	return -ENOBUFS;
}


static void
drain_scq(struct idt77252_dev *card, struct vc_map *vc)
{
	struct scq_info *scq = vc->scq;
	struct sk_buff *skb;
	struct atm_vcc *vcc;

	TXPRINTK("%s: SCQ (before drain %2d) next = 0x%p.\n",
		 card->name, atomic_read(&scq->used), scq->next);

	skb = skb_dequeue(&scq->transmit);
	if (skb) {
		TXPRINTK("%s: freeing skb at %p.\n", card->name, skb);

		pci_unmap_single(card->pcidev, IDT77252_PRV_PADDR(skb),
				 skb->len, PCI_DMA_TODEVICE);

		vcc = ATM_SKB(skb)->vcc;

		if (vcc->pop)
			vcc->pop(vcc, skb);
		else
			dev_kfree_skb(skb);

		atomic_inc(&vcc->stats->tx);
	}

	atomic_dec(&scq->used);

	spin_lock(&scq->skblock);
	while ((skb = skb_dequeue(&scq->pending))) {
		if (push_on_scq(card, vc, skb)) {
			skb_queue_head(&vc->scq->pending, skb);
			break;
		}
	}
	spin_unlock(&scq->skblock);
}

static int
queue_skb(struct idt77252_dev *card, struct vc_map *vc,
	  struct sk_buff *skb, int oam)
{
	struct atm_vcc *vcc;
	struct scqe *tbd;
	unsigned long flags;
	int error;
	int aal;

	if (skb->len == 0) {
		printk("%s: invalid skb->len (%d)\n", card->name, skb->len);
		return -EINVAL;
	}

	TXPRINTK("%s: Sending %d bytes of data.\n",
		 card->name, skb->len);

	tbd = &IDT77252_PRV_TBD(skb);
	vcc = ATM_SKB(skb)->vcc;

	IDT77252_PRV_PADDR(skb) = pci_map_single(card->pcidev, skb->data,
						 skb->len, PCI_DMA_TODEVICE);

	error = -EINVAL;

	if (oam) {
		if (skb->len != 52)
			goto errout;

		tbd->word_1 = SAR_TBD_OAM | ATM_CELL_PAYLOAD | SAR_TBD_EPDU;
		tbd->word_2 = IDT77252_PRV_PADDR(skb) + 4;
		tbd->word_3 = 0x00000000;
		tbd->word_4 = (skb->data[0] << 24) | (skb->data[1] << 16) |
			      (skb->data[2] <<  8) | (skb->data[3] <<  0);

		if (test_bit(VCF_RSV, &vc->flags))
			vc = card->vcs[0];

		goto done;
	}

	if (test_bit(VCF_RSV, &vc->flags)) {
		printk("%s: Trying to transmit on reserved VC\n", card->name);
		goto errout;
	}

	aal = vcc->qos.aal;

	switch (aal) {
	case ATM_AAL0:
	case ATM_AAL34:
		if (skb->len > 52)
			goto errout;

		if (aal == ATM_AAL0)
			tbd->word_1 = SAR_TBD_EPDU | SAR_TBD_AAL0 |
				      ATM_CELL_PAYLOAD;
		else
			tbd->word_1 = SAR_TBD_EPDU | SAR_TBD_AAL34 |
				      ATM_CELL_PAYLOAD;

		tbd->word_2 = IDT77252_PRV_PADDR(skb) + 4;
		tbd->word_3 = 0x00000000;
		tbd->word_4 = (skb->data[0] << 24) | (skb->data[1] << 16) |
			      (skb->data[2] <<  8) | (skb->data[3] <<  0);
		break;

	case ATM_AAL5:
		tbd->word_1 = SAR_TBD_EPDU | SAR_TBD_AAL5 | skb->len;
		tbd->word_2 = IDT77252_PRV_PADDR(skb);
		tbd->word_3 = skb->len;
		tbd->word_4 = (vcc->vpi << SAR_TBD_VPI_SHIFT) |
			      (vcc->vci << SAR_TBD_VCI_SHIFT);
		break;

	case ATM_AAL1:
	case ATM_AAL2:
	default:
		printk("%s: Traffic type not supported.\n", card->name);
		error = -EPROTONOSUPPORT;
		goto errout;
	}

done:
	spin_lock_irqsave(&vc->scq->skblock, flags);
	skb_queue_tail(&vc->scq->pending, skb);

	while ((skb = skb_dequeue(&vc->scq->pending))) {
		if (push_on_scq(card, vc, skb)) {
			skb_queue_head(&vc->scq->pending, skb);
			break;
		}
	}
	spin_unlock_irqrestore(&vc->scq->skblock, flags);

	return 0;

errout:
	pci_unmap_single(card->pcidev, IDT77252_PRV_PADDR(skb),
			 skb->len, PCI_DMA_TODEVICE);
	return error;
}

static unsigned long
get_free_scd(struct idt77252_dev *card, struct vc_map *vc)
{
	int i;

	for (i = 0; i < card->scd_size; i++) {
		if (!card->scd2vc[i]) {
			card->scd2vc[i] = vc;
			vc->scd_index = i;
			return card->scd_base + i * SAR_SRAM_SCD_SIZE;
		}
	}
	return 0;
}

static void
fill_scd(struct idt77252_dev *card, struct scq_info *scq, int class)
{
	write_sram(card, scq->scd, scq->paddr);
	write_sram(card, scq->scd + 1, 0x00000000);
	write_sram(card, scq->scd + 2, 0xffffffff);
	write_sram(card, scq->scd + 3, 0x00000000);
}

static void
clear_scd(struct idt77252_dev *card, struct scq_info *scq, int class)
{
	return;
}

/*****************************************************************************/
/*                                                                           */
/* RSQ Handling                                                              */
/*                                                                           */
/*****************************************************************************/

static int
init_rsq(struct idt77252_dev *card)
{
	struct rsq_entry *rsqe;

	card->rsq.base = pci_alloc_consistent(card->pcidev, RSQSIZE,
					      &card->rsq.paddr);
	if (card->rsq.base == NULL) {
		printk("%s: can't allocate RSQ.\n", card->name);
		return -1;
	}
	memset(card->rsq.base, 0, RSQSIZE);

	card->rsq.last = card->rsq.base + RSQ_NUM_ENTRIES - 1;
	card->rsq.next = card->rsq.last;
	for (rsqe = card->rsq.base; rsqe <= card->rsq.last; rsqe++)
		rsqe->word_4 = 0;

	writel((unsigned long) card->rsq.last - (unsigned long) card->rsq.base,
	       SAR_REG_RSQH);
	writel(card->rsq.paddr, SAR_REG_RSQB);

	IPRINTK("%s: RSQ base at 0x%lx (0x%x).\n", card->name,
		(unsigned long) card->rsq.base,
		readl(SAR_REG_RSQB));
	IPRINTK("%s: RSQ head = 0x%x, base = 0x%x, tail = 0x%x.\n",
		card->name,
		readl(SAR_REG_RSQH),
		readl(SAR_REG_RSQB),
		readl(SAR_REG_RSQT));

	return 0;
}

static void
deinit_rsq(struct idt77252_dev *card)
{
	pci_free_consistent(card->pcidev, RSQSIZE,
			    card->rsq.base, card->rsq.paddr);
}

static void
dequeue_rx(struct idt77252_dev *card, struct rsq_entry *rsqe)
{
	struct atm_vcc *vcc;
	struct sk_buff *skb;
	struct rx_pool *rpp;
	struct vc_map *vc;
	u32 header, vpi, vci;
	u32 stat;
	int i;

	stat = le32_to_cpu(rsqe->word_4);

	if (stat & SAR_RSQE_IDLE) {
		RXPRINTK("%s: message about inactive connection.\n",
			 card->name);
		return;
	}

	skb = sb_pool_skb(card, le32_to_cpu(rsqe->word_2));
	if (skb == NULL) {
		printk("%s: NULL skb in %s, rsqe: %08x %08x %08x %08x\n",
		       card->name, __FUNCTION__,
		       le32_to_cpu(rsqe->word_1), le32_to_cpu(rsqe->word_2),
		       le32_to_cpu(rsqe->word_3), le32_to_cpu(rsqe->word_4));
		return;
	}

	header = le32_to_cpu(rsqe->word_1);
	vpi = (header >> 16) & 0x00ff;
	vci = (header >>  0) & 0xffff;

	RXPRINTK("%s: SDU for %d.%d received in buffer 0x%p (data 0x%p).\n",
		 card->name, vpi, vci, skb, skb->data);

	if ((vpi >= (1 << card->vpibits)) || (vci != (vci & card->vcimask))) {
		printk("%s: SDU received for out-of-range vc %u.%u\n",
		       card->name, vpi, vci);
		recycle_rx_skb(card, skb);
		return;
	}

	vc = card->vcs[VPCI2VC(card, vpi, vci)];
	if (!vc || !test_bit(VCF_RX, &vc->flags)) {
		printk("%s: SDU received on non RX vc %u.%u\n",
		       card->name, vpi, vci);
		recycle_rx_skb(card, skb);
		return;
	}

	vcc = vc->rx_vcc;

	pci_dma_sync_single_for_cpu(card->pcidev, IDT77252_PRV_PADDR(skb),
				    skb->end - skb->data, PCI_DMA_FROMDEVICE);

	if ((vcc->qos.aal == ATM_AAL0) ||
	    (vcc->qos.aal == ATM_AAL34)) {
		struct sk_buff *sb;
		unsigned char *cell;
		u32 aal0;

		cell = skb->data;
		for (i = (stat & SAR_RSQE_CELLCNT); i; i--) {
			if ((sb = dev_alloc_skb(64)) == NULL) {
				printk("%s: Can't allocate buffers for aal0.\n",
				       card->name);
				atomic_add(i, &vcc->stats->rx_drop);
				break;
			}
			if (!atm_charge(vcc, sb->truesize)) {
				RXPRINTK("%s: atm_charge() dropped aal0 packets.\n",
					 card->name);
				atomic_add(i - 1, &vcc->stats->rx_drop);
				dev_kfree_skb(sb);
				break;
			}
			aal0 = (vpi << ATM_HDR_VPI_SHIFT) |
			       (vci << ATM_HDR_VCI_SHIFT);
			aal0 |= (stat & SAR_RSQE_EPDU) ? 0x00000002 : 0;
			aal0 |= (stat & SAR_RSQE_CLP)  ? 0x00000001 : 0;

			*((u32 *) sb->data) = aal0;
			skb_put(sb, sizeof(u32));
			memcpy(skb_put(sb, ATM_CELL_PAYLOAD),
			       cell, ATM_CELL_PAYLOAD);

			ATM_SKB(sb)->vcc = vcc;
			do_gettimeofday(&sb->stamp);
			vcc->push(vcc, sb);
			atomic_inc(&vcc->stats->rx);

			cell += ATM_CELL_PAYLOAD;
		}

		recycle_rx_skb(card, skb);
		return;
	}
	if (vcc->qos.aal != ATM_AAL5) {
		printk("%s: Unexpected AAL type in dequeue_rx(): %d.\n",
		       card->name, vcc->qos.aal);
		recycle_rx_skb(card, skb);
		return;
	}
	skb->len = (stat & SAR_RSQE_CELLCNT) * ATM_CELL_PAYLOAD;

	rpp = &vc->rcv.rx_pool;

	rpp->len += skb->len;
	if (!rpp->count++)
		rpp->first = skb;
	*rpp->last = skb;
	rpp->last = &skb->next;

	if (stat & SAR_RSQE_EPDU) {
		unsigned char *l1l2;
		unsigned int len;

		l1l2 = (unsigned char *) ((unsigned long) skb->data + skb->len - 6);

		len = (l1l2[0] << 8) | l1l2[1];
		len = len ? len : 0x10000;

		RXPRINTK("%s: PDU has %d bytes.\n", card->name, len);

		if ((len + 8 > rpp->len) || (len + (47 + 8) < rpp->len)) {
			RXPRINTK("%s: AAL5 PDU size mismatch: %d != %d. "
			         "(CDC: %08x)\n",
			         card->name, len, rpp->len, readl(SAR_REG_CDC));
			recycle_rx_pool_skb(card, rpp);
			atomic_inc(&vcc->stats->rx_err);
			return;
		}
		if (stat & SAR_RSQE_CRC) {
			RXPRINTK("%s: AAL5 CRC error.\n", card->name);
			recycle_rx_pool_skb(card, rpp);
			atomic_inc(&vcc->stats->rx_err);
			return;
		}
		if (rpp->count > 1) {
			struct sk_buff *sb;

			skb = dev_alloc_skb(rpp->len);
			if (!skb) {
				RXPRINTK("%s: Can't alloc RX skb.\n",
					 card->name);
				recycle_rx_pool_skb(card, rpp);
				atomic_inc(&vcc->stats->rx_err);
				return;
			}
			if (!atm_charge(vcc, skb->truesize)) {
				recycle_rx_pool_skb(card, rpp);
				dev_kfree_skb(skb);
				return;
			}
			sb = rpp->first;
			for (i = 0; i < rpp->count; i++) {
				memcpy(skb_put(skb, sb->len),
				       sb->data, sb->len);
				sb = sb->next;
			}

			recycle_rx_pool_skb(card, rpp);

			skb_trim(skb, len);
			ATM_SKB(skb)->vcc = vcc;
			do_gettimeofday(&skb->stamp);

			vcc->push(vcc, skb);
			atomic_inc(&vcc->stats->rx);

			return;
		}

		skb->next = NULL;
		flush_rx_pool(card, rpp);

		if (!atm_charge(vcc, skb->truesize)) {
			recycle_rx_skb(card, skb);
			return;
		}

		pci_unmap_single(card->pcidev, IDT77252_PRV_PADDR(skb),
				 skb->end - skb->data, PCI_DMA_FROMDEVICE);
		sb_pool_remove(card, skb);

		skb_trim(skb, len);
		ATM_SKB(skb)->vcc = vcc;
		do_gettimeofday(&skb->stamp);

		vcc->push(vcc, skb);
		atomic_inc(&vcc->stats->rx);

		if (skb->truesize > SAR_FB_SIZE_3)
			add_rx_skb(card, 3, SAR_FB_SIZE_3, 1);
		else if (skb->truesize > SAR_FB_SIZE_2)
			add_rx_skb(card, 2, SAR_FB_SIZE_2, 1);
		else if (skb->truesize > SAR_FB_SIZE_1)
			add_rx_skb(card, 1, SAR_FB_SIZE_1, 1);
		else
			add_rx_skb(card, 0, SAR_FB_SIZE_0, 1);
		return;
	}
}

static void
idt77252_rx(struct idt77252_dev *card)
{
	struct rsq_entry *rsqe;

	if (card->rsq.next == card->rsq.last)
		rsqe = card->rsq.base;
	else
		rsqe = card->rsq.next + 1;

	if (!(le32_to_cpu(rsqe->word_4) & SAR_RSQE_VALID)) {
		RXPRINTK("%s: no entry in RSQ.\n", card->name);
		return;
	}

	do {
		dequeue_rx(card, rsqe);
		rsqe->word_4 = 0;
		card->rsq.next = rsqe;
		if (card->rsq.next == card->rsq.last)
			rsqe = card->rsq.base;
		else
			rsqe = card->rsq.next + 1;
	} while (le32_to_cpu(rsqe->word_4) & SAR_RSQE_VALID);

	writel((unsigned long) card->rsq.next - (unsigned long) card->rsq.base,
	       SAR_REG_RSQH);
}

static void
idt77252_rx_raw(struct idt77252_dev *card)
{
	struct sk_buff	*queue;
	u32		head, tail;
	struct atm_vcc	*vcc;
	struct vc_map	*vc;
	struct sk_buff	*sb;

	if (card->raw_cell_head == NULL) {
		u32 handle = le32_to_cpu(*(card->raw_cell_hnd + 1));
		card->raw_cell_head = sb_pool_skb(card, handle);
	}

	queue = card->raw_cell_head;
	if (!queue)
		return;

	head = IDT77252_PRV_PADDR(queue) + (queue->data - queue->head - 16);
	tail = readl(SAR_REG_RAWCT);

	pci_dma_sync_single_for_cpu(card->pcidev, IDT77252_PRV_PADDR(queue),
				    queue->end - queue->head - 16,
				    PCI_DMA_FROMDEVICE);

	while (head != tail) {
		unsigned int vpi, vci, pti;
		u32 header;

		header = le32_to_cpu(*(u32 *) &queue->data[0]);

		vpi = (header & ATM_HDR_VPI_MASK) >> ATM_HDR_VPI_SHIFT;
		vci = (header & ATM_HDR_VCI_MASK) >> ATM_HDR_VCI_SHIFT;
		pti = (header & ATM_HDR_PTI_MASK) >> ATM_HDR_PTI_SHIFT;

#ifdef CONFIG_ATM_IDT77252_DEBUG
		if (debug & DBG_RAW_CELL) {
			int i;

			printk("%s: raw cell %x.%02x.%04x.%x.%x\n",
			       card->name, (header >> 28) & 0x000f,
			       (header >> 20) & 0x00ff,
			       (header >>  4) & 0xffff,
			       (header >>  1) & 0x0007,
			       (header >>  0) & 0x0001);
			for (i = 16; i < 64; i++)
				printk(" %02x", queue->data[i]);
			printk("\n");
		}
#endif

		if (vpi >= (1<<card->vpibits) || vci >= (1<<card->vcibits)) {
			RPRINTK("%s: SDU received for out-of-range vc %u.%u\n",
				card->name, vpi, vci);
			goto drop;
		}

		vc = card->vcs[VPCI2VC(card, vpi, vci)];
		if (!vc || !test_bit(VCF_RX, &vc->flags)) {
			RPRINTK("%s: SDU received on non RX vc %u.%u\n",
				card->name, vpi, vci);
			goto drop;
		}

		vcc = vc->rx_vcc;

		if (vcc->qos.aal != ATM_AAL0) {
			RPRINTK("%s: raw cell for non AAL0 vc %u.%u\n",
				card->name, vpi, vci);
			atomic_inc(&vcc->stats->rx_drop);
			goto drop;
		}
	
		if ((sb = dev_alloc_skb(64)) == NULL) {
			printk("%s: Can't allocate buffers for AAL0.\n",
			       card->name);
			atomic_inc(&vcc->stats->rx_err);
			goto drop;
		}

		if (!atm_charge(vcc, sb->truesize)) {
			RXPRINTK("%s: atm_charge() dropped AAL0 packets.\n",
				 card->name);
			dev_kfree_skb(sb);
			goto drop;
		}

		*((u32 *) sb->data) = header;
		skb_put(sb, sizeof(u32));
		memcpy(skb_put(sb, ATM_CELL_PAYLOAD), &(queue->data[16]),
		       ATM_CELL_PAYLOAD);

		ATM_SKB(sb)->vcc = vcc;
		do_gettimeofday(&sb->stamp);
		vcc->push(vcc, sb);
		atomic_inc(&vcc->stats->rx);

drop:
		skb_pull(queue, 64);

		head = IDT77252_PRV_PADDR(queue)
					+ (queue->data - queue->head - 16);

		if (queue->len < 128) {
			struct sk_buff *next;
			u32 handle;

			head = le32_to_cpu(*(u32 *) &queue->data[0]);
			handle = le32_to_cpu(*(u32 *) &queue->data[4]);

			next = sb_pool_skb(card, handle);
			recycle_rx_skb(card, queue);

			if (next) {
				card->raw_cell_head = next;
				queue = card->raw_cell_head;
				pci_dma_sync_single_for_cpu(card->pcidev,
							    IDT77252_PRV_PADDR(queue),
							    queue->end - queue->data,
							    PCI_DMA_FROMDEVICE);
			} else {
				card->raw_cell_head = NULL;
				printk("%s: raw cell queue overrun\n",
				       card->name);
				break;
			}
		}
	}
}


/*****************************************************************************/
/*                                                                           */
/* TSQ Handling                                                              */
/*                                                                           */
/*****************************************************************************/

static int
init_tsq(struct idt77252_dev *card)
{
	struct tsq_entry *tsqe;

	card->tsq.base = pci_alloc_consistent(card->pcidev, RSQSIZE,
					      &card->tsq.paddr);
	if (card->tsq.base == NULL) {
		printk("%s: can't allocate TSQ.\n", card->name);
		return -1;
	}
	memset(card->tsq.base, 0, TSQSIZE);

	card->tsq.last = card->tsq.base + TSQ_NUM_ENTRIES - 1;
	card->tsq.next = card->tsq.last;
	for (tsqe = card->tsq.base; tsqe <= card->tsq.last; tsqe++)
		tsqe->word_2 = cpu_to_le32(SAR_TSQE_INVALID);

	writel(card->tsq.paddr, SAR_REG_TSQB);
	writel((unsigned long) card->tsq.next - (unsigned long) card->tsq.base,
	       SAR_REG_TSQH);

	return 0;
}

static void
deinit_tsq(struct idt77252_dev *card)
{
	pci_free_consistent(card->pcidev, TSQSIZE,
			    card->tsq.base, card->tsq.paddr);
}

static void
idt77252_tx(struct idt77252_dev *card)
{
	struct tsq_entry *tsqe;
	unsigned int vpi, vci;
	struct vc_map *vc;
	u32 conn, stat;

	if (card->tsq.next == card->tsq.last)
		tsqe = card->tsq.base;
	else
		tsqe = card->tsq.next + 1;

	TXPRINTK("idt77252_tx: tsq  %p: base %p, next %p, last %p\n", tsqe,
		 card->tsq.base, card->tsq.next, card->tsq.last);
	TXPRINTK("idt77252_tx: tsqb %08x, tsqt %08x, tsqh %08x, \n",
		 readl(SAR_REG_TSQB),
		 readl(SAR_REG_TSQT),
		 readl(SAR_REG_TSQH));

	stat = le32_to_cpu(tsqe->word_2);

	if (stat & SAR_TSQE_INVALID)
		return;

	do {
		TXPRINTK("tsqe: 0x%p [0x%08x 0x%08x]\n", tsqe,
			 le32_to_cpu(tsqe->word_1),
			 le32_to_cpu(tsqe->word_2));

		switch (stat & SAR_TSQE_TYPE) {
		case SAR_TSQE_TYPE_TIMER:
			TXPRINTK("%s: Timer RollOver detected.\n", card->name);
			break;

		case SAR_TSQE_TYPE_IDLE:

			conn = le32_to_cpu(tsqe->word_1);

			if (SAR_TSQE_TAG(stat) == 0x10) {
#ifdef	NOTDEF
				printk("%s: Connection %d halted.\n",
				       card->name,
				       le32_to_cpu(tsqe->word_1) & 0x1fff);
#endif
				break;
			}

			vc = card->vcs[conn & 0x1fff];
			if (!vc) {
				printk("%s: could not find VC from conn %d\n",
				       card->name, conn & 0x1fff);
				break;
			}

			printk("%s: Connection %d IDLE.\n",
			       card->name, vc->index);

			set_bit(VCF_IDLE, &vc->flags);
			break;

		case SAR_TSQE_TYPE_TSR:

			conn = le32_to_cpu(tsqe->word_1);

			vc = card->vcs[conn & 0x1fff];
			if (!vc) {
				printk("%s: no VC at index %d\n",
				       card->name,
				       le32_to_cpu(tsqe->word_1) & 0x1fff);
				break;
			}

			drain_scq(card, vc);
			break;

		case SAR_TSQE_TYPE_TBD_COMP:

			conn = le32_to_cpu(tsqe->word_1);

			vpi = (conn >> SAR_TBD_VPI_SHIFT) & 0x00ff;
			vci = (conn >> SAR_TBD_VCI_SHIFT) & 0xffff;

			if (vpi >= (1 << card->vpibits) ||
			    vci >= (1 << card->vcibits)) {
				printk("%s: TBD complete: "
				       "out of range VPI.VCI %u.%u\n",
				       card->name, vpi, vci);
				break;
			}

			vc = card->vcs[VPCI2VC(card, vpi, vci)];
			if (!vc) {
				printk("%s: TBD complete: "
				       "no VC at VPI.VCI %u.%u\n",
				       card->name, vpi, vci);
				break;
			}

			drain_scq(card, vc);
			break;
		}

		tsqe->word_2 = cpu_to_le32(SAR_TSQE_INVALID);

		card->tsq.next = tsqe;
		if (card->tsq.next == card->tsq.last)
			tsqe = card->tsq.base;
		else
			tsqe = card->tsq.next + 1;

		TXPRINTK("tsqe: %p: base %p, next %p, last %p\n", tsqe,
			 card->tsq.base, card->tsq.next, card->tsq.last);

		stat = le32_to_cpu(tsqe->word_2);

	} while (!(stat & SAR_TSQE_INVALID));

	writel((unsigned long)card->tsq.next - (unsigned long)card->tsq.base,
	       SAR_REG_TSQH);

	XPRINTK("idt77252_tx-after writel%d: TSQ head = 0x%x, tail = 0x%x, next = 0x%p.\n",
		card->index, readl(SAR_REG_TSQH),
		readl(SAR_REG_TSQT), card->tsq.next);
}


static void
tst_timer(unsigned long data)
{
	struct idt77252_dev *card = (struct idt77252_dev *)data;
	unsigned long base, idle, jump;
	unsigned long flags;
	u32 pc;
	int e;

	spin_lock_irqsave(&card->tst_lock, flags);

	base = card->tst[card->tst_index];
	idle = card->tst[card->tst_index ^ 1];

	if (test_bit(TST_SWITCH_WAIT, &card->tst_state)) {
		jump = base + card->tst_size - 2;

		pc = readl(SAR_REG_NOW) >> 2;
		if ((pc ^ idle) & ~(card->tst_size - 1)) {
			mod_timer(&card->tst_timer, jiffies + 1);
			goto out;
		}

		clear_bit(TST_SWITCH_WAIT, &card->tst_state);

		card->tst_index ^= 1;
		write_sram(card, jump, TSTE_OPC_JMP | (base << 2));

		base = card->tst[card->tst_index];
		idle = card->tst[card->tst_index ^ 1];

		for (e = 0; e < card->tst_size - 2; e++) {
			if (card->soft_tst[e].tste & TSTE_PUSH_IDLE) {
				write_sram(card, idle + e,
					   card->soft_tst[e].tste & TSTE_MASK);
				card->soft_tst[e].tste &= ~(TSTE_PUSH_IDLE);
			}
		}
	}

	if (test_and_clear_bit(TST_SWITCH_PENDING, &card->tst_state)) {

		for (e = 0; e < card->tst_size - 2; e++) {
			if (card->soft_tst[e].tste & TSTE_PUSH_ACTIVE) {
				write_sram(card, idle + e,
					   card->soft_tst[e].tste & TSTE_MASK);
				card->soft_tst[e].tste &= ~(TSTE_PUSH_ACTIVE);
				card->soft_tst[e].tste |= TSTE_PUSH_IDLE;
			}
		}

		jump = base + card->tst_size - 2;

		write_sram(card, jump, TSTE_OPC_NULL);
		set_bit(TST_SWITCH_WAIT, &card->tst_state);

		mod_timer(&card->tst_timer, jiffies + 1);
	}

out:
	spin_unlock_irqrestore(&card->tst_lock, flags);
}

static int
__fill_tst(struct idt77252_dev *card, struct vc_map *vc,
	   int n, unsigned int opc)
{
	unsigned long cl, avail;
	unsigned long idle;
	int e, r;
	u32 data;

	avail = card->tst_size - 2;
	for (e = 0; e < avail; e++) {
		if (card->soft_tst[e].vc == NULL)
			break;
	}
	if (e >= avail) {
		printk("%s: No free TST entries found\n", card->name);
		return -1;
	}

	NPRINTK("%s: conn %d: first TST entry at %d.\n",
		card->name, vc ? vc->index : -1, e);

	r = n;
	cl = avail;
	data = opc & TSTE_OPC_MASK;
	if (vc && (opc != TSTE_OPC_NULL))
		data = opc | vc->index;

	idle = card->tst[card->tst_index ^ 1];

	/*
	 * Fill Soft TST.
	 */
	while (r > 0) {
		if ((cl >= avail) && (card->soft_tst[e].vc == NULL)) {
			if (vc)
				card->soft_tst[e].vc = vc;
			else
				card->soft_tst[e].vc = (void *)-1;

			card->soft_tst[e].tste = data;
			if (timer_pending(&card->tst_timer))
				card->soft_tst[e].tste |= TSTE_PUSH_ACTIVE;
			else {
				write_sram(card, idle + e, data);
				card->soft_tst[e].tste |= TSTE_PUSH_IDLE;
			}

			cl -= card->tst_size;
			r--;
		}

		if (++e == avail)
			e = 0;
		cl += n;
	}

	return 0;
}

static int
fill_tst(struct idt77252_dev *card, struct vc_map *vc, int n, unsigned int opc)
{
	unsigned long flags;
	int res;

	spin_lock_irqsave(&card->tst_lock, flags);

	res = __fill_tst(card, vc, n, opc);

	set_bit(TST_SWITCH_PENDING, &card->tst_state);
	if (!timer_pending(&card->tst_timer))
		mod_timer(&card->tst_timer, jiffies + 1);

	spin_unlock_irqrestore(&card->tst_lock, flags);
	return res;
}

static int
__clear_tst(struct idt77252_dev *card, struct vc_map *vc)
{
	unsigned long idle;
	int e;

	idle = card->tst[card->tst_index ^ 1];

	for (e = 0; e < card->tst_size - 2; e++) {
		if (card->soft_tst[e].vc == vc) {
			card->soft_tst[e].vc = NULL;

			card->soft_tst[e].tste = TSTE_OPC_VAR;
			if (timer_pending(&card->tst_timer))
				card->soft_tst[e].tste |= TSTE_PUSH_ACTIVE;
			else {
				write_sram(card, idle + e, TSTE_OPC_VAR);
				card->soft_tst[e].tste |= TSTE_PUSH_IDLE;
			}
		}
	}

	return 0;
}

static int
clear_tst(struct idt77252_dev *card, struct vc_map *vc)
{
	unsigned long flags;
	int res;

	spin_lock_irqsave(&card->tst_lock, flags);

	res = __clear_tst(card, vc);

	set_bit(TST_SWITCH_PENDING, &card->tst_state);
	if (!timer_pending(&card->tst_timer))
		mod_timer(&card->tst_timer, jiffies + 1);

	spin_unlock_irqrestore(&card->tst_lock, flags);
	return res;
}

static int
change_tst(struct idt77252_dev *card, struct vc_map *vc,
	   int n, unsigned int opc)
{
	unsigned long flags;
	int res;

	spin_lock_irqsave(&card->tst_lock, flags);

	__clear_tst(card, vc);
	res = __fill_tst(card, vc, n, opc);

	set_bit(TST_SWITCH_PENDING, &card->tst_state);
	if (!timer_pending(&card->tst_timer))
		mod_timer(&card->tst_timer, jiffies + 1);

	spin_unlock_irqrestore(&card->tst_lock, flags);
	return res;
}


static int
set_tct(struct idt77252_dev *card, struct vc_map *vc)
{
	unsigned long tct;

	tct = (unsigned long) (card->tct_base + vc->index * SAR_SRAM_TCT_SIZE);

	switch (vc->class) {
	case SCHED_CBR:
		OPRINTK("%s: writing TCT at 0x%lx, SCD 0x%lx.\n",
		        card->name, tct, vc->scq->scd);

		write_sram(card, tct + 0, TCT_CBR | vc->scq->scd);
		write_sram(card, tct + 1, 0);
		write_sram(card, tct + 2, 0);
		write_sram(card, tct + 3, 0);
		write_sram(card, tct + 4, 0);
		write_sram(card, tct + 5, 0);
		write_sram(card, tct + 6, 0);
		write_sram(card, tct + 7, 0);
		break;

	case SCHED_UBR:
		OPRINTK("%s: writing TCT at 0x%lx, SCD 0x%lx.\n",
		        card->name, tct, vc->scq->scd);

		write_sram(card, tct + 0, TCT_UBR | vc->scq->scd);
		write_sram(card, tct + 1, 0);
		write_sram(card, tct + 2, TCT_TSIF);
		write_sram(card, tct + 3, TCT_HALT | TCT_IDLE);
		write_sram(card, tct + 4, 0);
		write_sram(card, tct + 5, vc->init_er);
		write_sram(card, tct + 6, 0);
		write_sram(card, tct + 7, TCT_FLAG_UBR);
		break;

	case SCHED_VBR:
	case SCHED_ABR:
	default:
		return -ENOSYS;
	}

	return 0;
}

/*****************************************************************************/
/*                                                                           */
/* FBQ Handling                                                              */
/*                                                                           */
/*****************************************************************************/

static __inline__ int
idt77252_fbq_level(struct idt77252_dev *card, int queue)
{
	return (readl(SAR_REG_STAT) >> (16 + (queue << 2))) & 0x0f;
}

static __inline__ int
idt77252_fbq_full(struct idt77252_dev *card, int queue)
{
	return (readl(SAR_REG_STAT) >> (16 + (queue << 2))) == 0x0f;
}

static int
push_rx_skb(struct idt77252_dev *card, struct sk_buff *skb, int queue)
{
	unsigned long flags;
	u32 handle;
	u32 addr;

	skb->data = skb->tail = skb->head;
	skb->len = 0;

	skb_reserve(skb, 16);

	switch (queue) {
	case 0:
		skb_put(skb, SAR_FB_SIZE_0);
		break;
	case 1:
		skb_put(skb, SAR_FB_SIZE_1);
		break;
	case 2:
		skb_put(skb, SAR_FB_SIZE_2);
		break;
	case 3:
		skb_put(skb, SAR_FB_SIZE_3);
		break;
	default:
		dev_kfree_skb(skb);
		return -1;
	}

	if (idt77252_fbq_full(card, queue))
		return -1;

	memset(&skb->data[(skb->len & ~(0x3f)) - 64], 0, 2 * sizeof(u32));

	handle = IDT77252_PRV_POOL(skb);
	addr = IDT77252_PRV_PADDR(skb);

	spin_lock_irqsave(&card->cmd_lock, flags);
	writel(handle, card->fbq[queue]);
	writel(addr, card->fbq[queue]);
	spin_unlock_irqrestore(&card->cmd_lock, flags);

	return 0;
}

static void
add_rx_skb(struct idt77252_dev *card, int queue,
	   unsigned int size, unsigned int count)
{
	struct sk_buff *skb;
	dma_addr_t paddr;
	u32 handle;

	while (count--) {
		skb = dev_alloc_skb(size);
		if (!skb)
			return;

		if (sb_pool_add(card, skb, queue)) {
			printk("%s: SB POOL full\n", __FUNCTION__);
			goto outfree;
		}

		paddr = pci_map_single(card->pcidev, skb->data,
				       skb->end - skb->data,
				       PCI_DMA_FROMDEVICE);
		IDT77252_PRV_PADDR(skb) = paddr;

		if (push_rx_skb(card, skb, queue)) {
			printk("%s: FB QUEUE full\n", __FUNCTION__);
			goto outunmap;
		}
	}

	return;

outunmap:
	pci_unmap_single(card->pcidev, IDT77252_PRV_PADDR(skb),
			 skb->end - skb->data, PCI_DMA_FROMDEVICE);

	handle = IDT77252_PRV_POOL(skb);
	card->sbpool[POOL_QUEUE(handle)].skb[POOL_INDEX(handle)] = NULL;

outfree:
	dev_kfree_skb(skb);
}


static void
recycle_rx_skb(struct idt77252_dev *card, struct sk_buff *skb)
{
	u32 handle = IDT77252_PRV_POOL(skb);
	int err;

	pci_dma_sync_single_for_device(card->pcidev, IDT77252_PRV_PADDR(skb),
				       skb->end - skb->data, PCI_DMA_FROMDEVICE);

	err = push_rx_skb(card, skb, POOL_QUEUE(handle));
	if (err) {
		pci_unmap_single(card->pcidev, IDT77252_PRV_PADDR(skb),
				 skb->end - skb->data, PCI_DMA_FROMDEVICE);
		sb_pool_remove(card, skb);
		dev_kfree_skb(skb);
	}
}

static void
flush_rx_pool(struct idt77252_dev *card, struct rx_pool *rpp)
{
	rpp->len = 0;
	rpp->count = 0;
	rpp->first = NULL;
	rpp->last = &rpp->first;
}

static void
recycle_rx_pool_skb(struct idt77252_dev *card, struct rx_pool *rpp)
{
	struct sk_buff *skb, *next;
	int i;

	skb = rpp->first;
	for (i = 0; i < rpp->count; i++) {
		next = skb->next;
		skb->next = NULL;
		recycle_rx_skb(card, skb);
		skb = next;
	}
	flush_rx_pool(card, rpp);
}

/*****************************************************************************/
/*                                                                           */
/* ATM Interface                                                             */
/*                                                                           */
/*****************************************************************************/

static void
idt77252_phy_put(struct atm_dev *dev, unsigned char value, unsigned long addr)
{
	write_utility(dev->dev_data, 0x100 + (addr & 0x1ff), value);
}

static unsigned char
idt77252_phy_get(struct atm_dev *dev, unsigned long addr)
{
	return read_utility(dev->dev_data, 0x100 + (addr & 0x1ff));
}

static inline int
idt77252_send_skb(struct atm_vcc *vcc, struct sk_buff *skb, int oam)
{
	struct atm_dev *dev = vcc->dev;
	struct idt77252_dev *card = dev->dev_data;
	struct vc_map *vc = vcc->dev_data;
	int err;

	if (vc == NULL) {
		printk("%s: NULL connection in send().\n", card->name);
		atomic_inc(&vcc->stats->tx_err);
		dev_kfree_skb(skb);
		return -EINVAL;
	}
	if (!test_bit(VCF_TX, &vc->flags)) {
		printk("%s: Trying to transmit on a non-tx VC.\n", card->name);
		atomic_inc(&vcc->stats->tx_err);
		dev_kfree_skb(skb);
		return -EINVAL;
	}

	switch (vcc->qos.aal) {
	case ATM_AAL0:
	case ATM_AAL1:
	case ATM_AAL5:
		break;
	default:
		printk("%s: Unsupported AAL: %d\n", card->name, vcc->qos.aal);
		atomic_inc(&vcc->stats->tx_err);
		dev_kfree_skb(skb);
		return -EINVAL;
	}

	if (skb_shinfo(skb)->nr_frags != 0) {
		printk("%s: No scatter-gather yet.\n", card->name);
		atomic_inc(&vcc->stats->tx_err);
		dev_kfree_skb(skb);
		return -EINVAL;
	}
	ATM_SKB(skb)->vcc = vcc;

	err = queue_skb(card, vc, skb, oam);
	if (err) {
		atomic_inc(&vcc->stats->tx_err);
		dev_kfree_skb(skb);
		return err;
	}

	return 0;
}

int
idt77252_send(struct atm_vcc *vcc, struct sk_buff *skb)
{
	return idt77252_send_skb(vcc, skb, 0);
}

static int
idt77252_send_oam(struct atm_vcc *vcc, void *cell, int flags)
{
	struct atm_dev *dev = vcc->dev;
	struct idt77252_dev *card = dev->dev_data;
	struct sk_buff *skb;

	skb = dev_alloc_skb(64);
	if (!skb) {
		printk("%s: Out of memory in send_oam().\n", card->name);
		atomic_inc(&vcc->stats->tx_err);
		return -ENOMEM;
	}
	atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);

	memcpy(skb_put(skb, 52), cell, 52);

	return idt77252_send_skb(vcc, skb, 1);
}

static __inline__ unsigned int
idt77252_fls(unsigned int x)
{
	int r = 1;

	if (x == 0)
		return 0;
	if (x & 0xffff0000) {
		x >>= 16;
		r += 16;
	}
	if (x & 0xff00) {
		x >>= 8;
		r += 8;
	}
	if (x & 0xf0) {
		x >>= 4;
		r += 4;
	}
	if (x & 0xc) {
		x >>= 2;
		r += 2;
	}
	if (x & 0x2)
		r += 1;
	return r;
}

static u16
idt77252_int_to_atmfp(unsigned int rate)
{
	u16 m, e;

	if (rate == 0)
		return 0;
	e = idt77252_fls(rate) - 1;
	if (e < 9)
		m = (rate - (1 << e)) << (9 - e);
	else if (e == 9)
		m = (rate - (1 << e));
	else /* e > 9 */
		m = (rate - (1 << e)) >> (e - 9);
	return 0x4000 | (e << 9) | m;
}

static u8
idt77252_rate_logindex(struct idt77252_dev *card, int pcr)
{
	u16 afp;

	afp = idt77252_int_to_atmfp(pcr < 0 ? -pcr : pcr);
	if (pcr < 0)
		return rate_to_log[(afp >> 5) & 0x1ff];
	return rate_to_log[((afp >> 5) + 1) & 0x1ff];
}

static void
idt77252_est_timer(unsigned long data)
{
	struct vc_map *vc = (struct vc_map *)data;
	struct idt77252_dev *card = vc->card;
	struct rate_estimator *est;
	unsigned long flags;
	u32 rate, cps;
	u64 ncells;
	u8 lacr;

	spin_lock_irqsave(&vc->lock, flags);
	est = vc->estimator;
	if (!est)
		goto out;

	ncells = est->cells;

	rate = ((u32)(ncells - est->last_cells)) << (7 - est->interval);
	est->last_cells = ncells;
	est->avcps += ((long)rate - (long)est->avcps) >> est->ewma_log;
	est->cps = (est->avcps + 0x1f) >> 5;

	cps = est->cps;
	if (cps < (est->maxcps >> 4))
		cps = est->maxcps >> 4;

	lacr = idt77252_rate_logindex(card, cps);
	if (lacr > vc->max_er)
		lacr = vc->max_er;

	if (lacr != vc->lacr) {
		vc->lacr = lacr;
		writel(TCMDQ_LACR|(vc->lacr << 16)|vc->index, SAR_REG_TCMDQ);
	}

	est->timer.expires = jiffies + ((HZ / 4) << est->interval);
	add_timer(&est->timer);

out:
	spin_unlock_irqrestore(&vc->lock, flags);
}

static struct rate_estimator *
idt77252_init_est(struct vc_map *vc, int pcr)
{
	struct rate_estimator *est;

	est = kmalloc(sizeof(struct rate_estimator), GFP_KERNEL);
	if (!est)
		return NULL;
	memset(est, 0, sizeof(*est));

	est->maxcps = pcr < 0 ? -pcr : pcr;
	est->cps = est->maxcps;
	est->avcps = est->cps << 5;

	est->interval = 2;		/* XXX: make this configurable */
	est->ewma_log = 2;		/* XXX: make this c…