diff options
Diffstat (limited to 'drivers/isdn/pcbit/layer2.c')
-rw-r--r-- | drivers/isdn/pcbit/layer2.c | 712 |
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"); -} |