zatm.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 1,628 行 · 第 1/3 页

/* drivers/atm/zatm.c - ZeitNet ZN122x device driver */
 
/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */


#include <linux/config.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/pci.h>
#include <linux/errno.h>
#include <linux/atm.h>
#include <linux/atmdev.h>
#include <linux/sonet.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/delay.h>
#include <linux/ioport.h> /* for request_region */
#include <linux/uio.h>
#include <linux/init.h>
#include <linux/atm_zatm.h>
#include <linux/capability.h>
#include <linux/bitops.h>
#include <asm/byteorder.h>
#include <asm/system.h>
#include <asm/string.h>
#include <asm/io.h>
#include <asm/atomic.h>
#include <asm/uaccess.h>

#include "uPD98401.h"
#include "uPD98402.h"
#include "zeprom.h"
#include "zatm.h"


/*
 * TODO:
 *
 * Minor features
 *  - support 64 kB SDUs (will have to use multibuffer batches then :-( )
 *  - proper use of CDV, credit = max(1,CDVT*PCR)
 *  - AAL0
 *  - better receive timestamps
 *  - OAM
 */

#if 0
#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
#else
#define DPRINTK(format,args...)
#endif

#ifndef CONFIG_ATM_ZATM_DEBUG


#define NULLCHECK(x)

#define EVENT(s,a,b)


static void event_dump(void)
{
}


#else


/* 
 * NULL pointer checking
 */

#define NULLCHECK(x) \
  if ((unsigned long) (x) < 0x30) printk(KERN_CRIT #x "==0x%x\n", (int) (x))

/*
 * Very extensive activity logging. Greatly improves bug detection speed but
 * costs a few Mbps if enabled.
 */

#define EV 64

static const char *ev[EV];
static unsigned long ev_a[EV],ev_b[EV];
static int ec = 0;


static void EVENT(const char *s,unsigned long a,unsigned long b)
{
	ev[ec] = s; 
	ev_a[ec] = a;
	ev_b[ec] = b;
	ec = (ec+1) % EV;
}


static void event_dump(void)
{
	int n,i;

	printk(KERN_NOTICE "----- event dump follows -----\n");
	for (n = 0; n < EV; n++) {
		i = (ec+n) % EV;
		printk(KERN_NOTICE);
		printk(ev[i] ? ev[i] : "(null)",ev_a[i],ev_b[i]);
	}
	printk(KERN_NOTICE "----- event dump ends here -----\n");
}


#endif /* CONFIG_ATM_ZATM_DEBUG */


#define RING_BUSY	1	/* indication from do_tx that PDU has to be
				   backlogged */

static struct atm_dev *zatm_boards = NULL;
static unsigned long dummy[2] = {0,0};


#define zin_n(r) inl(zatm_dev->base+r*4)
#define zin(r) inl(zatm_dev->base+uPD98401_##r*4)
#define zout(v,r) outl(v,zatm_dev->base+uPD98401_##r*4)
#define zwait while (zin(CMR) & uPD98401_BUSY)

/* RX0, RX1, TX0, TX1 */
static const int mbx_entries[NR_MBX] = { 1024,1024,1024,1024 };
static const int mbx_esize[NR_MBX] = { 16,16,4,4 }; /* entry size in bytes */

#define MBX_SIZE(i) (mbx_entries[i]*mbx_esize[i])


/*-------------------------------- utilities --------------------------------*/


static void zpokel(struct zatm_dev *zatm_dev,u32 value,u32 addr)
{
	zwait;
	zout(value,CER);
	zout(uPD98401_IND_ACC | uPD98401_IA_BALL |
	    (uPD98401_IA_TGT_CM << uPD98401_IA_TGT_SHIFT) | addr,CMR);
}


static u32 zpeekl(struct zatm_dev *zatm_dev,u32 addr)
{
	zwait;
	zout(uPD98401_IND_ACC | uPD98401_IA_BALL | uPD98401_IA_RW |
	  (uPD98401_IA_TGT_CM << uPD98401_IA_TGT_SHIFT) | addr,CMR);
	zwait;
	return zin(CER);
}


/*------------------------------- free lists --------------------------------*/


/*
 * Free buffer head structure:
 *   [0] pointer to buffer (for SAR)
 *   [1] buffer descr link pointer (for SAR)
 *   [2] back pointer to skb (for poll_rx)
 *   [3] data
 *   ...
 */

struct rx_buffer_head {
	u32		buffer;	/* pointer to buffer (for SAR) */
	u32		link;	/* buffer descriptor link pointer (for SAR) */
	struct sk_buff	*skb;	/* back pointer to skb (for poll_rx) */
};


static void refill_pool(struct atm_dev *dev,int pool)
{
	struct zatm_dev *zatm_dev;
	struct sk_buff *skb;
	struct rx_buffer_head *first;
	unsigned long flags;
	int align,offset,free,count,size;

	EVENT("refill_pool\n",0,0);
	zatm_dev = ZATM_DEV(dev);
	size = (64 << (pool <= ZATM_AAL5_POOL_BASE ? 0 :
	    pool-ZATM_AAL5_POOL_BASE))+sizeof(struct rx_buffer_head);
	if (size < PAGE_SIZE) {
		align = 32; /* for 32 byte alignment */
		offset = sizeof(struct rx_buffer_head);
	}
	else {
		align = 4096;
		offset = zatm_dev->pool_info[pool].offset+
		    sizeof(struct rx_buffer_head);
	}
	size += align;
	spin_lock_irqsave(&zatm_dev->lock, flags);
	free = zpeekl(zatm_dev,zatm_dev->pool_base+2*pool) &
	    uPD98401_RXFP_REMAIN;
	spin_unlock_irqrestore(&zatm_dev->lock, flags);
	if (free >= zatm_dev->pool_info[pool].low_water) return;
	EVENT("starting ... POOL: 0x%x, 0x%x\n",
	    zpeekl(zatm_dev,zatm_dev->pool_base+2*pool),
	    zpeekl(zatm_dev,zatm_dev->pool_base+2*pool+1));
	EVENT("dummy: 0x%08lx, 0x%08lx\n",dummy[0],dummy[1]);
	count = 0;
	first = NULL;
	while (free < zatm_dev->pool_info[pool].high_water) {
		struct rx_buffer_head *head;

		skb = alloc_skb(size,GFP_ATOMIC);
		if (!skb) {
			printk(KERN_WARNING DEV_LABEL "(Itf %d): got no new "
			    "skb (%d) with %d free\n",dev->number,size,free);
			break;
		}
		skb_reserve(skb,(unsigned char *) ((((unsigned long) skb->data+
		    align+offset-1) & ~(unsigned long) (align-1))-offset)-
		    skb->data);
		head = (struct rx_buffer_head *) skb->data;
		skb_reserve(skb,sizeof(struct rx_buffer_head));
		if (!first) first = head;
		count++;
		head->buffer = virt_to_bus(skb->data);
		head->link = 0;
		head->skb = skb;
		EVENT("enq skb 0x%08lx/0x%08lx\n",(unsigned long) skb,
		    (unsigned long) head);
		spin_lock_irqsave(&zatm_dev->lock, flags);
		if (zatm_dev->last_free[pool])
			((struct rx_buffer_head *) (zatm_dev->last_free[pool]->
			    data))[-1].link = virt_to_bus(head);
		zatm_dev->last_free[pool] = skb;
		skb_queue_tail(&zatm_dev->pool[pool],skb);
		spin_unlock_irqrestore(&zatm_dev->lock, flags);
		free++;
	}
	if (first) {
		spin_lock_irqsave(&zatm_dev->lock, flags);
		zwait;
		zout(virt_to_bus(first),CER);
		zout(uPD98401_ADD_BAT | (pool << uPD98401_POOL_SHIFT) | count,
		    CMR);
		spin_unlock_irqrestore(&zatm_dev->lock, flags);
		EVENT ("POOL: 0x%x, 0x%x\n",
		    zpeekl(zatm_dev,zatm_dev->pool_base+2*pool),
		    zpeekl(zatm_dev,zatm_dev->pool_base+2*pool+1));
		EVENT("dummy: 0x%08lx, 0x%08lx\n",dummy[0],dummy[1]);
	}
}


static void drain_free(struct atm_dev *dev,int pool)
{
	skb_queue_purge(&ZATM_DEV(dev)->pool[pool]);
}


static int pool_index(int max_pdu)
{
	int i;

	if (max_pdu % ATM_CELL_PAYLOAD)
		printk(KERN_ERR DEV_LABEL ": driver error in pool_index: "
		    "max_pdu is %d\n",max_pdu);
	if (max_pdu > 65536) return -1;
	for (i = 0; (64 << i) < max_pdu; i++);
	return i+ZATM_AAL5_POOL_BASE;
}


/* use_pool isn't reentrant */


static void use_pool(struct atm_dev *dev,int pool)
{
	struct zatm_dev *zatm_dev;
	unsigned long flags;
	int size;

	zatm_dev = ZATM_DEV(dev);
	if (!(zatm_dev->pool_info[pool].ref_count++)) {
		skb_queue_head_init(&zatm_dev->pool[pool]);
		size = pool-ZATM_AAL5_POOL_BASE;
		if (size < 0) size = 0; /* 64B... */
		else if (size > 10) size = 10; /* ... 64kB */
		spin_lock_irqsave(&zatm_dev->lock, flags);
		zpokel(zatm_dev,((zatm_dev->pool_info[pool].low_water/4) <<
		    uPD98401_RXFP_ALERT_SHIFT) |
		    (1 << uPD98401_RXFP_BTSZ_SHIFT) |
		    (size << uPD98401_RXFP_BFSZ_SHIFT),
		    zatm_dev->pool_base+pool*2);
		zpokel(zatm_dev,(unsigned long) dummy,zatm_dev->pool_base+
		    pool*2+1);
		spin_unlock_irqrestore(&zatm_dev->lock, flags);
		zatm_dev->last_free[pool] = NULL;
		refill_pool(dev,pool);
	}
	DPRINTK("pool %d: %d\n",pool,zatm_dev->pool_info[pool].ref_count);
}


static void unuse_pool(struct atm_dev *dev,int pool)
{
	if (!(--ZATM_DEV(dev)->pool_info[pool].ref_count))
		drain_free(dev,pool);
}

/*----------------------------------- RX ------------------------------------*/


#if 0
static void exception(struct atm_vcc *vcc)
{
   static int count = 0;
   struct zatm_dev *zatm_dev = ZATM_DEV(vcc->dev);
   struct zatm_vcc *zatm_vcc = ZATM_VCC(vcc);
   unsigned long *qrp;
   int i;

   if (count++ > 2) return;
   for (i = 0; i < 8; i++)
	printk("TX%d: 0x%08lx\n",i,
	  zpeekl(zatm_dev,zatm_vcc->tx_chan*VC_SIZE/4+i));
   for (i = 0; i < 5; i++)
	printk("SH%d: 0x%08lx\n",i,
	  zpeekl(zatm_dev,uPD98401_IM(zatm_vcc->shaper)+16*i));
   qrp = (unsigned long *) zpeekl(zatm_dev,zatm_vcc->tx_chan*VC_SIZE/4+
     uPD98401_TXVC_QRP);
   printk("qrp=0x%08lx\n",(unsigned long) qrp);
   for (i = 0; i < 4; i++) printk("QRP[%d]: 0x%08lx",i,qrp[i]);
}
#endif


static const char *err_txt[] = {
	"No error",
	"RX buf underflow",
	"RX FIFO overrun",
	"Maximum len violation",
	"CRC error",
	"User abort",
	"Length violation",
	"T1 error",
	"Deactivated",
	"???",
	"???",
	"???",
	"???",
	"???",
	"???",
	"???"
};


static void poll_rx(struct atm_dev *dev,int mbx)
{
	struct zatm_dev *zatm_dev;
	unsigned long pos;
	u32 x;
	int error;

	EVENT("poll_rx\n",0,0);
	zatm_dev = ZATM_DEV(dev);
	pos = (zatm_dev->mbx_start[mbx] & ~0xffffUL) | zin(MTA(mbx));
	while (x = zin(MWA(mbx)), (pos & 0xffff) != x) {
		u32 *here;
		struct sk_buff *skb;
		struct atm_vcc *vcc;
		int cells,size,chan;

		EVENT("MBX: host 0x%lx, nic 0x%x\n",pos,x);
		here = (u32 *) pos;
		if (((pos += 16) & 0xffff) == zatm_dev->mbx_end[mbx])
			pos = zatm_dev->mbx_start[mbx];
		cells = here[0] & uPD98401_AAL5_SIZE;
#if 0
printk("RX IND: 0x%x, 0x%x, 0x%x, 0x%x\n",here[0],here[1],here[2],here[3]);
{
unsigned long *x;
		printk("POOL: 0x%08x, 0x%08x\n",zpeekl(zatm_dev,
		      zatm_dev->pool_base),
		      zpeekl(zatm_dev,zatm_dev->pool_base+1));
		x = (unsigned long *) here[2];
		printk("[0..3] = 0x%08lx, 0x%08lx, 0x%08lx, 0x%08lx\n",
		    x[0],x[1],x[2],x[3]);
}
#endif
		error = 0;
		if (here[3] & uPD98401_AAL5_ERR) {
			error = (here[3] & uPD98401_AAL5_ES) >>
			    uPD98401_AAL5_ES_SHIFT;
			if (error == uPD98401_AAL5_ES_DEACT ||
			    error == uPD98401_AAL5_ES_FREE) continue;
		}
EVENT("error code 0x%x/0x%x\n",(here[3] & uPD98401_AAL5_ES) >>
  uPD98401_AAL5_ES_SHIFT,error);
		skb = ((struct rx_buffer_head *) bus_to_virt(here[2]))->skb;
		do_gettimeofday(&skb->stamp);
#if 0
printk("[-3..0] 0x%08lx 0x%08lx 0x%08lx 0x%08lx\n",((unsigned *) skb->data)[-3],
  ((unsigned *) skb->data)[-2],((unsigned *) skb->data)[-1],
  ((unsigned *) skb->data)[0]);
#endif
		EVENT("skb 0x%lx, here 0x%lx\n",(unsigned long) skb,
		    (unsigned long) here);
#if 0
printk("dummy: 0x%08lx, 0x%08lx\n",dummy[0],dummy[1]);
#endif
		size = error ? 0 : ntohs(((u16 *) skb->data)[cells*
		    ATM_CELL_PAYLOAD/sizeof(u16)-3]);
		EVENT("got skb 0x%lx, size %d\n",(unsigned long) skb,size);
		chan = (here[3] & uPD98401_AAL5_CHAN) >>
		    uPD98401_AAL5_CHAN_SHIFT;
		if (chan < zatm_dev->chans && zatm_dev->rx_map[chan]) {
			vcc = zatm_dev->rx_map[chan];
			if (skb == zatm_dev->last_free[ZATM_VCC(vcc)->pool])
				zatm_dev->last_free[ZATM_VCC(vcc)->pool] = NULL;
			skb_unlink(skb);
		}
		else {
			printk(KERN_ERR DEV_LABEL "(itf %d): RX indication "
			    "for non-existing channel\n",dev->number);
			size = 0;
			vcc = NULL;
			event_dump();
		}
		if (error) {
			static unsigned long silence = 0;
			static int last_error = 0;

			if (error != last_error ||
			    time_after(jiffies, silence)  || silence == 0){
				printk(KERN_WARNING DEV_LABEL "(itf %d): "
				    "chan %d error %s\n",dev->number,chan,
				    err_txt[error]);
				last_error = error;
				silence = (jiffies+2*HZ)|1;
			}
			size = 0;
		}
		if (size && (size > cells*ATM_CELL_PAYLOAD-ATM_AAL5_TRAILER ||
		    size <= (cells-1)*ATM_CELL_PAYLOAD-ATM_AAL5_TRAILER)) {
			printk(KERN_ERR DEV_LABEL "(itf %d): size %d with %d "
			    "cells\n",dev->number,size,cells);
			size = 0;
			event_dump();
		}
		if (size > ATM_MAX_AAL5_PDU) {
			printk(KERN_ERR DEV_LABEL "(itf %d): size too big "
			    "(%d)\n",dev->number,size);
			size = 0;
			event_dump();
		}
		if (!size) {
			dev_kfree_skb_irq(skb);
			if (vcc) atomic_inc(&vcc->stats->rx_err);
			continue;
		}
		if (!atm_charge(vcc,skb->truesize)) {
			dev_kfree_skb_irq(skb);
			continue;
		}
		skb->len = size;
		ATM_SKB(skb)->vcc = vcc;
		vcc->push(vcc,skb);
		atomic_inc(&vcc->stats->rx);
	}
	zout(pos & 0xffff,MTA(mbx));
#if 0 /* probably a stupid idea */
	refill_pool(dev,zatm_vcc->pool);
		/* maybe this saves us a few interrupts */
#endif
}


static int open_rx_first(struct atm_vcc *vcc)
{
	struct zatm_dev *zatm_dev;
	struct zatm_vcc *zatm_vcc;
	unsigned long flags;
	unsigned short chan;
	int cells;

	DPRINTK("open_rx_first (0x%x)\n",inb_p(0xc053));
	zatm_dev = ZATM_DEV(vcc->dev);
	zatm_vcc = ZATM_VCC(vcc);
	zatm_vcc->rx_chan = 0;
	if (vcc->qos.rxtp.traffic_class == ATM_NONE) return 0;
	if (vcc->qos.aal == ATM_AAL5) {
		if (vcc->qos.rxtp.max_sdu > 65464)
			vcc->qos.rxtp.max_sdu = 65464;
			/* fix this - we may want to receive 64kB SDUs
			   later */
		cells = (vcc->qos.rxtp.max_sdu+ATM_AAL5_TRAILER+
		    ATM_CELL_PAYLOAD-1)/ATM_CELL_PAYLOAD;
		zatm_vcc->pool = pool_index(cells*ATM_CELL_PAYLOAD);
	}
	else {
		cells = 1;
		zatm_vcc->pool = ZATM_AAL0_POOL;
	}
	if (zatm_vcc->pool < 0) return -EMSGSIZE;
	spin_lock_irqsave(&zatm_dev->lock, flags);
	zwait;
	zout(uPD98401_OPEN_CHAN,CMR);
	zwait;
	DPRINTK("0x%x 0x%x\n",zin(CMR),zin(CER));
	chan = (zin(CMR) & uPD98401_CHAN_ADDR) >> uPD98401_CHAN_ADDR_SHIFT;
	spin_unlock_irqrestore(&zatm_dev->lock, flags);
	DPRINTK("chan is %d\n",chan);
	if (!chan) return -EAGAIN;
	use_pool(vcc->dev,zatm_vcc->pool);
	DPRINTK("pool %d\n",zatm_vcc->pool);
	/* set up VC descriptor */
	spin_lock_irqsave(&zatm_dev->lock, flags);
	zpokel(zatm_dev,zatm_vcc->pool << uPD98401_RXVC_POOL_SHIFT,
	    chan*VC_SIZE/4);
	zpokel(zatm_dev,uPD98401_RXVC_OD | (vcc->qos.aal == ATM_AAL5 ?
	    uPD98401_RXVC_AR : 0) | cells,chan*VC_SIZE/4+1);
	zpokel(zatm_dev,0,chan*VC_SIZE/4+2);
	zatm_vcc->rx_chan = chan;
	zatm_dev->rx_map[chan] = vcc;
	spin_unlock_irqrestore(&zatm_dev->lock, flags);
	return 0;
}


static int open_rx_second(struct atm_vcc *vcc)
{
	struct zatm_dev *zatm_dev;
	struct zatm_vcc *zatm_vcc;
	unsigned long flags;
	int pos,shift;

	DPRINTK("open_rx_second (0x%x)\n",inb_p(0xc053));
	zatm_dev = ZATM_DEV(vcc->dev);
	zatm_vcc = ZATM_VCC(vcc);
	if (!zatm_vcc->rx_chan) return 0;
	spin_lock_irqsave(&zatm_dev->lock, flags);
	/* should also handle VPI @@@ */
	pos = vcc->vci >> 1;