Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/drivers/isdn/pcbit/layer2.c b/drivers/isdn/pcbit/layer2.c
new file mode 100644
index 0000000..ba76693
--- /dev/null
+++ b/drivers/isdn/pcbit/layer2.c
@@ -0,0 +1,732 @@
+/*
+ * 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/sched.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/types.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/system.h>
+#include <asm/io.h>
+
+
+#include "pcbit.h"
+#include "layer2.h"
+#include "edss1.h"
+
+#undef DEBUG_FRAG
+
+
+
+/*
+ * task queue struct
+ */
+
+
+
+/*
+ * Layer 3 packet demultiplexer
+ * drv.c
+ */
+
+extern void pcbit_l3_receive(struct pcbit_dev *dev, ulong msg,
+ struct sk_buff *skb,
+ ushort hdr_len, ushort refnum);
+
+/*
+ * Prototypes
+ */
+
+void pcbit_deliver(void *data);
+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 = (struct frame_buf *) kmalloc(sizeof(struct frame_buf),
+ GFP_ATOMIC)) == NULL) {
+ printk(KERN_WARNING "pcbit_2_write: kmalloc failed\n");
+ 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(void *data)
+{
+ struct frame_buf *frame;
+ unsigned long flags, msg;
+ struct pcbit_dev *dev = (struct pcbit_dev *) data;
+
+ spin_lock_irqsave(&dev->lock, flags);
+
+ while ((frame = dev->read_queue)) {
+ dev->read_queue = frame->next;
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ 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 */
+ if (dev->read_frame->skb)
+ kfree_skb(dev->read_frame->skb);
+ kfree(dev->read_frame);
+ dev->read_frame = NULL;
+ }
+ frame = kmalloc(sizeof(struct frame_buf), GFP_ATOMIC);
+
+ if (frame == NULL) {
+ printk(KERN_WARNING "kmalloc failed\n");
+ return;
+ }
+ memset(frame, 0, sizeof(struct frame_buf));
+
+ 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 pt_regs *regs)
+{
+ 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 hander\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) {
+ if (dev->read_frame->skb)
+ 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");
+}