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path: root/drivers/isdn/pcbit/layer2.c
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Diffstat (limited to 'drivers/isdn/pcbit/layer2.c')
-rw-r--r--drivers/isdn/pcbit/layer2.c712
1 files changed, 0 insertions, 712 deletions
diff --git a/drivers/isdn/pcbit/layer2.c b/drivers/isdn/pcbit/layer2.c
deleted file mode 100644
index 46e1240ae074..000000000000
--- a/drivers/isdn/pcbit/layer2.c
+++ /dev/null
@@ -1,712 +0,0 @@
-/*
- * PCBIT-D low-layer interface
- *
- * Copyright (C) 1996 Universidade de Lisboa
- *
- * Written by Pedro Roque Marques (roque@di.fc.ul.pt)
- *
- * This software may be used and distributed according to the terms of
- * the GNU General Public License, incorporated herein by reference.
- */
-
-/*
- * 19991203 - Fernando Carvalho - takion@superbofh.org
- * Hacked to compile with egcs and run with current version of isdn modules
- */
-
-/*
- * Based on documentation provided by Inesc:
- * - "Interface com bus do PC para o PCBIT e PCBIT-D", Inesc, Jan 93
- */
-
-/*
- * TODO: better handling of errors
- * re-write/remove debug printks
- */
-
-#include <linux/string.h>
-#include <linux/kernel.h>
-#include <linux/types.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/interrupt.h>
-#include <linux/workqueue.h>
-#include <linux/mm.h>
-#include <linux/skbuff.h>
-
-#include <linux/isdnif.h>
-
-#include <asm/io.h>
-
-
-#include "pcbit.h"
-#include "layer2.h"
-#include "edss1.h"
-
-#undef DEBUG_FRAG
-
-
-/*
- * Prototypes
- */
-
-static void pcbit_transmit(struct pcbit_dev *dev);
-
-static void pcbit_recv_ack(struct pcbit_dev *dev, unsigned char ack);
-
-static void pcbit_l2_error(struct pcbit_dev *dev);
-static void pcbit_l2_active_conf(struct pcbit_dev *dev, u_char info);
-static void pcbit_l2_err_recover(unsigned long data);
-
-static void pcbit_firmware_bug(struct pcbit_dev *dev);
-
-static __inline__ void
-pcbit_sched_delivery(struct pcbit_dev *dev)
-{
- schedule_work(&dev->qdelivery);
-}
-
-
-/*
- * Called from layer3
- */
-
-int
-pcbit_l2_write(struct pcbit_dev *dev, ulong msg, ushort refnum,
- struct sk_buff *skb, unsigned short hdr_len)
-{
- struct frame_buf *frame,
- *ptr;
- unsigned long flags;
-
- if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING) {
- dev_kfree_skb(skb);
- return -1;
- }
- if ((frame = kmalloc(sizeof(struct frame_buf),
- GFP_ATOMIC)) == NULL) {
- dev_kfree_skb(skb);
- return -1;
- }
- frame->msg = msg;
- frame->refnum = refnum;
- frame->copied = 0;
- frame->hdr_len = hdr_len;
-
- if (skb)
- frame->dt_len = skb->len - hdr_len;
- else
- frame->dt_len = 0;
-
- frame->skb = skb;
-
- frame->next = NULL;
-
- spin_lock_irqsave(&dev->lock, flags);
-
- if (dev->write_queue == NULL) {
- dev->write_queue = frame;
- spin_unlock_irqrestore(&dev->lock, flags);
- pcbit_transmit(dev);
- } else {
- for (ptr = dev->write_queue; ptr->next; ptr = ptr->next);
- ptr->next = frame;
-
- spin_unlock_irqrestore(&dev->lock, flags);
- }
- return 0;
-}
-
-static __inline__ void
-pcbit_tx_update(struct pcbit_dev *dev, ushort len)
-{
- u_char info;
-
- dev->send_seq = (dev->send_seq + 1) % 8;
-
- dev->fsize[dev->send_seq] = len;
- info = 0;
- info |= dev->rcv_seq << 3;
- info |= dev->send_seq;
-
- writeb(info, dev->sh_mem + BANK4);
-
-}
-
-/*
- * called by interrupt service routine or by write_2
- */
-
-static void
-pcbit_transmit(struct pcbit_dev *dev)
-{
- struct frame_buf *frame = NULL;
- unsigned char unacked;
- int flen; /* fragment frame length including all headers */
- int free;
- int count,
- cp_len;
- unsigned long flags;
- unsigned short tt;
-
- if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING)
- return;
-
- unacked = (dev->send_seq + (8 - dev->unack_seq)) & 0x07;
-
- spin_lock_irqsave(&dev->lock, flags);
-
- if (dev->free > 16 && dev->write_queue && unacked < 7) {
-
- if (!dev->w_busy)
- dev->w_busy = 1;
- else {
- spin_unlock_irqrestore(&dev->lock, flags);
- return;
- }
-
-
- frame = dev->write_queue;
- free = dev->free;
-
- spin_unlock_irqrestore(&dev->lock, flags);
-
- if (frame->copied == 0) {
-
- /* Type 0 frame */
-
- ulong msg;
-
- if (frame->skb)
- flen = FRAME_HDR_LEN + PREHDR_LEN + frame->skb->len;
- else
- flen = FRAME_HDR_LEN + PREHDR_LEN;
-
- if (flen > free)
- flen = free;
-
- msg = frame->msg;
-
- /*
- * Board level 2 header
- */
-
- pcbit_writew(dev, flen - FRAME_HDR_LEN);
-
- pcbit_writeb(dev, GET_MSG_CPU(msg));
-
- pcbit_writeb(dev, GET_MSG_PROC(msg));
-
- /* TH */
- pcbit_writew(dev, frame->hdr_len + PREHDR_LEN);
-
- /* TD */
- pcbit_writew(dev, frame->dt_len);
-
-
- /*
- * Board level 3 fixed-header
- */
-
- /* LEN = TH */
- pcbit_writew(dev, frame->hdr_len + PREHDR_LEN);
-
- /* XX */
- pcbit_writew(dev, 0);
-
- /* C + S */
- pcbit_writeb(dev, GET_MSG_CMD(msg));
- pcbit_writeb(dev, GET_MSG_SCMD(msg));
-
- /* NUM */
- pcbit_writew(dev, frame->refnum);
-
- count = FRAME_HDR_LEN + PREHDR_LEN;
- } else {
- /* Type 1 frame */
-
- flen = 2 + (frame->skb->len - frame->copied);
-
- if (flen > free)
- flen = free;
-
- /* TT */
- tt = ((ushort) (flen - 2)) | 0x8000U; /* Type 1 */
- pcbit_writew(dev, tt);
-
- count = 2;
- }
-
- if (frame->skb) {
- cp_len = frame->skb->len - frame->copied;
- if (cp_len > flen - count)
- cp_len = flen - count;
-
- memcpy_topcbit(dev, frame->skb->data + frame->copied,
- cp_len);
- frame->copied += cp_len;
- }
- /* bookkeeping */
- dev->free -= flen;
- pcbit_tx_update(dev, flen);
-
- spin_lock_irqsave(&dev->lock, flags);
-
- if (frame->skb == NULL || frame->copied == frame->skb->len) {
-
- dev->write_queue = frame->next;
-
- if (frame->skb != NULL) {
- /* free frame */
- dev_kfree_skb(frame->skb);
- }
- kfree(frame);
- }
- dev->w_busy = 0;
- spin_unlock_irqrestore(&dev->lock, flags);
- } else {
- spin_unlock_irqrestore(&dev->lock, flags);
-#ifdef DEBUG
- printk(KERN_DEBUG "unacked %d free %d write_queue %s\n",
- unacked, dev->free, dev->write_queue ? "not empty" :
- "empty");
-#endif
- }
-}
-
-
-/*
- * deliver a queued frame to the upper layer
- */
-
-void
-pcbit_deliver(struct work_struct *work)
-{
- struct frame_buf *frame;
- unsigned long flags, msg;
- struct pcbit_dev *dev =
- container_of(work, struct pcbit_dev, qdelivery);
-
- spin_lock_irqsave(&dev->lock, flags);
-
- while ((frame = dev->read_queue)) {
- dev->read_queue = frame->next;
- spin_unlock_irqrestore(&dev->lock, flags);
-
- msg = 0;
- SET_MSG_CPU(msg, 0);
- SET_MSG_PROC(msg, 0);
- SET_MSG_CMD(msg, frame->skb->data[2]);
- SET_MSG_SCMD(msg, frame->skb->data[3]);
-
- frame->refnum = *((ushort *)frame->skb->data + 4);
- frame->msg = *((ulong *)&msg);
-
- skb_pull(frame->skb, 6);
-
- pcbit_l3_receive(dev, frame->msg, frame->skb, frame->hdr_len,
- frame->refnum);
-
- kfree(frame);
-
- spin_lock_irqsave(&dev->lock, flags);
- }
-
- spin_unlock_irqrestore(&dev->lock, flags);
-}
-
-/*
- * Reads BANK 2 & Reassembles
- */
-
-static void
-pcbit_receive(struct pcbit_dev *dev)
-{
- unsigned short tt;
- u_char cpu,
- proc;
- struct frame_buf *frame = NULL;
- unsigned long flags;
- u_char type1;
-
- if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING)
- return;
-
- tt = pcbit_readw(dev);
-
- if ((tt & 0x7fffU) > 511) {
- printk(KERN_INFO "pcbit: invalid frame length -> TT=%04x\n",
- tt);
- pcbit_l2_error(dev);
- return;
- }
- if (!(tt & 0x8000U)) { /* Type 0 */
- type1 = 0;
-
- if (dev->read_frame) {
- printk(KERN_DEBUG "pcbit_receive: Type 0 frame and read_frame != NULL\n");
- /* discard previous queued frame */
- kfree_skb(dev->read_frame->skb);
- kfree(dev->read_frame);
- dev->read_frame = NULL;
- }
- frame = kzalloc(sizeof(struct frame_buf), GFP_ATOMIC);
-
- if (frame == NULL) {
- printk(KERN_WARNING "kmalloc failed\n");
- return;
- }
-
- cpu = pcbit_readb(dev);
- proc = pcbit_readb(dev);
-
-
- if (cpu != 0x06 && cpu != 0x02) {
- printk(KERN_DEBUG "pcbit: invalid cpu value\n");
- kfree(frame);
- pcbit_l2_error(dev);
- return;
- }
- /*
- * we discard cpu & proc on receiving
- * but we read it to update the pointer
- */
-
- frame->hdr_len = pcbit_readw(dev);
- frame->dt_len = pcbit_readw(dev);
-
- /*
- * 0 sized packet
- * I don't know if they are an error or not...
- * But they are very frequent
- * Not documented
- */
-
- if (frame->hdr_len == 0) {
- kfree(frame);
-#ifdef DEBUG
- printk(KERN_DEBUG "0 sized frame\n");
-#endif
- pcbit_firmware_bug(dev);
- return;
- }
- /* sanity check the length values */
- if (frame->hdr_len > 1024 || frame->dt_len > 2048) {
-#ifdef DEBUG
- printk(KERN_DEBUG "length problem: ");
- printk(KERN_DEBUG "TH=%04x TD=%04x\n",
- frame->hdr_len,
- frame->dt_len);
-#endif
- pcbit_l2_error(dev);
- kfree(frame);
- return;
- }
- /* minimum frame read */
-
- frame->skb = dev_alloc_skb(frame->hdr_len + frame->dt_len +
- ((frame->hdr_len + 15) & ~15));
-
- if (!frame->skb) {
- printk(KERN_DEBUG "pcbit_receive: out of memory\n");
- kfree(frame);
- return;
- }
- /* 16 byte alignment for IP */
- if (frame->dt_len)
- skb_reserve(frame->skb, (frame->hdr_len + 15) & ~15);
-
- } else {
- /* Type 1 */
- type1 = 1;
- tt &= 0x7fffU;
-
- if (!(frame = dev->read_frame)) {
- printk("Type 1 frame and no frame queued\n");
- /* usually after an error: toss frame */
- dev->readptr += tt;
- if (dev->readptr > dev->sh_mem + BANK2 + BANKLEN)
- dev->readptr -= BANKLEN;
- return;
-
- }
- }
-
- memcpy_frompcbit(dev, skb_put(frame->skb, tt), tt);
-
- frame->copied += tt;
- spin_lock_irqsave(&dev->lock, flags);
- if (frame->copied == frame->hdr_len + frame->dt_len) {
-
- if (type1) {
- dev->read_frame = NULL;
- }
- if (dev->read_queue) {
- struct frame_buf *ptr;
- for (ptr = dev->read_queue; ptr->next; ptr = ptr->next);
- ptr->next = frame;
- } else
- dev->read_queue = frame;
-
- } else {
- dev->read_frame = frame;
- }
- spin_unlock_irqrestore(&dev->lock, flags);
-}
-
-/*
- * The board sends 0 sized frames
- * They are TDATA_CONFs that get messed up somehow
- * gotta send a fake acknowledgment to the upper layer somehow
- */
-
-static __inline__ void
-pcbit_fake_conf(struct pcbit_dev *dev, struct pcbit_chan *chan)
-{
- isdn_ctrl ictl;
-
- if (chan->queued) {
- chan->queued--;
-
- ictl.driver = dev->id;
- ictl.command = ISDN_STAT_BSENT;
- ictl.arg = chan->id;
- dev->dev_if->statcallb(&ictl);
- }
-}
-
-static void
-pcbit_firmware_bug(struct pcbit_dev *dev)
-{
- struct pcbit_chan *chan;
-
- chan = dev->b1;
-
- if (chan->fsm_state == ST_ACTIVE) {
- pcbit_fake_conf(dev, chan);
- }
- chan = dev->b2;
-
- if (chan->fsm_state == ST_ACTIVE) {
- pcbit_fake_conf(dev, chan);
- }
-}
-
-irqreturn_t
-pcbit_irq_handler(int interrupt, void *devptr)
-{
- struct pcbit_dev *dev;
- u_char info,
- ack_seq,
- read_seq;
-
- dev = (struct pcbit_dev *) devptr;
-
- if (!dev) {
- printk(KERN_WARNING "pcbit_irq_handler: wrong device\n");
- return IRQ_NONE;
- }
- if (dev->interrupt) {
- printk(KERN_DEBUG "pcbit: reentering interrupt handler\n");
- return IRQ_HANDLED;
- }
- dev->interrupt = 1;
-
- info = readb(dev->sh_mem + BANK3);
-
- if (dev->l2_state == L2_STARTING || dev->l2_state == L2_ERROR) {
- pcbit_l2_active_conf(dev, info);
- dev->interrupt = 0;
- return IRQ_HANDLED;
- }
- if (info & 0x40U) { /* E bit set */
-#ifdef DEBUG
- printk(KERN_DEBUG "pcbit_irq_handler: E bit on\n");
-#endif
- pcbit_l2_error(dev);
- dev->interrupt = 0;
- return IRQ_HANDLED;
- }
- if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING) {
- dev->interrupt = 0;
- return IRQ_HANDLED;
- }
- ack_seq = (info >> 3) & 0x07U;
- read_seq = (info & 0x07U);
-
- dev->interrupt = 0;
-
- if (read_seq != dev->rcv_seq) {
- while (read_seq != dev->rcv_seq) {
- pcbit_receive(dev);
- dev->rcv_seq = (dev->rcv_seq + 1) % 8;
- }
- pcbit_sched_delivery(dev);
- }
- if (ack_seq != dev->unack_seq) {
- pcbit_recv_ack(dev, ack_seq);
- }
- info = dev->rcv_seq << 3;
- info |= dev->send_seq;
-
- writeb(info, dev->sh_mem + BANK4);
- return IRQ_HANDLED;
-}
-
-
-static void
-pcbit_l2_active_conf(struct pcbit_dev *dev, u_char info)
-{
- u_char state;
-
- state = dev->l2_state;
-
-#ifdef DEBUG
- printk(KERN_DEBUG "layer2_active_confirm\n");
-#endif
-
-
- if (info & 0x80U) {
- dev->rcv_seq = info & 0x07U;
- dev->l2_state = L2_RUNNING;
- } else
- dev->l2_state = L2_DOWN;
-
- if (state == L2_STARTING)
- wake_up_interruptible(&dev->set_running_wq);
-
- if (state == L2_ERROR && dev->l2_state == L2_RUNNING) {
- pcbit_transmit(dev);
- }
-}
-
-static void
-pcbit_l2_err_recover(unsigned long data)
-{
-
- struct pcbit_dev *dev;
- struct frame_buf *frame;
-
- dev = (struct pcbit_dev *) data;
-
- del_timer(&dev->error_recover_timer);
- if (dev->w_busy || dev->r_busy) {
- init_timer(&dev->error_recover_timer);
- dev->error_recover_timer.expires = jiffies + ERRTIME;
- add_timer(&dev->error_recover_timer);
- return;
- }
- dev->w_busy = dev->r_busy = 1;
-
- if (dev->read_frame) {
- kfree_skb(dev->read_frame->skb);
- kfree(dev->read_frame);
- dev->read_frame = NULL;
- }
- if (dev->write_queue) {
- frame = dev->write_queue;
-#ifdef FREE_ON_ERROR
- dev->write_queue = dev->write_queue->next;
-
- if (frame->skb) {
- dev_kfree_skb(frame->skb);
- }
- kfree(frame);
-#else
- frame->copied = 0;
-#endif
- }
- dev->rcv_seq = dev->send_seq = dev->unack_seq = 0;
- dev->free = 511;
- dev->l2_state = L2_ERROR;
-
- /* this is an hack... */
- pcbit_firmware_bug(dev);
-
- dev->writeptr = dev->sh_mem;
- dev->readptr = dev->sh_mem + BANK2;
-
- writeb((0x80U | ((dev->rcv_seq & 0x07) << 3) | (dev->send_seq & 0x07)),
- dev->sh_mem + BANK4);
- dev->w_busy = dev->r_busy = 0;
-
-}
-
-static void
-pcbit_l2_error(struct pcbit_dev *dev)
-{
- if (dev->l2_state == L2_RUNNING) {
-
- printk(KERN_INFO "pcbit: layer 2 error\n");
-
-#ifdef DEBUG
- log_state(dev);
-#endif
-
- dev->l2_state = L2_DOWN;
-
- init_timer(&dev->error_recover_timer);
- dev->error_recover_timer.function = &pcbit_l2_err_recover;
- dev->error_recover_timer.data = (ulong) dev;
- dev->error_recover_timer.expires = jiffies + ERRTIME;
- add_timer(&dev->error_recover_timer);
- }
-}
-
-/*
- * Description:
- * if board acks frames
- * update dev->free
- * call pcbit_transmit to write possible queued frames
- */
-
-static void
-pcbit_recv_ack(struct pcbit_dev *dev, unsigned char ack)
-{
- int i,
- count;
- int unacked;
-
- unacked = (dev->send_seq + (8 - dev->unack_seq)) & 0x07;
-
- /* dev->unack_seq < ack <= dev->send_seq; */
-
- if (unacked) {
-
- if (dev->send_seq > dev->unack_seq) {
- if (ack <= dev->unack_seq || ack > dev->send_seq) {
- printk(KERN_DEBUG
- "layer 2 ack unacceptable - dev %d",
- dev->id);
-
- pcbit_l2_error(dev);
- } else if (ack > dev->send_seq && ack <= dev->unack_seq) {
- printk(KERN_DEBUG
- "layer 2 ack unacceptable - dev %d",
- dev->id);
- pcbit_l2_error(dev);
- }
- }
- /* ack is acceptable */
-
-
- i = dev->unack_seq;
-
- do {
- dev->unack_seq = i = (i + 1) % 8;
- dev->free += dev->fsize[i];
- } while (i != ack);
-
- count = 0;
- while (count < 7 && dev->write_queue) {
- u8 lsend_seq = dev->send_seq;
-
- pcbit_transmit(dev);
-
- if (dev->send_seq == lsend_seq)
- break;
- count++;
- }
- } else
- printk(KERN_DEBUG "recv_ack: unacked = 0\n");
-}