video1394.c

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	/* set the sync flag */
	if (flags & VIDEO1394_SYNC_FRAMES)
		ir_prg[0].control |= 0x00030000;

	ir_prg[0].address = kvirt_to_bus(buf);
	ir_prg[0].branchAddress =  (virt_to_bus(&(ir_prg[1].control)) 
				    & 0xfffffff0) | 0x1;

	/* the second descriptor will read PAGE_SIZE-4 bytes */
	ir_prg[1].control = (0x280C << 16) | (PAGE_SIZE-4);
	ir_prg[1].address = kvirt_to_bus(buf+4);
	ir_prg[1].branchAddress =  (virt_to_bus(&(ir_prg[2].control)) 
				    & 0xfffffff0) | 0x1;
	
	for (i=2;i<d->nb_cmd-1;i++) {
		ir_prg[i].control = (0x280C << 16) | PAGE_SIZE;
		ir_prg[i].address = kvirt_to_bus(buf+(i-1)*PAGE_SIZE);

		ir_prg[i].branchAddress =  
			(virt_to_bus(&(ir_prg[i+1].control)) 
			 & 0xfffffff0) | 0x1;
	}

	/* the last descriptor will generate an interrupt */
	ir_prg[i].control = (0x283C << 16) | d->left_size;
	ir_prg[i].address = kvirt_to_bus(buf+(i-1)*PAGE_SIZE);
}
	
static void initialize_dma_ir_ctx(struct dma_iso_ctx *d, int tag, int flags)
{
	struct ti_ohci *ohci = (struct ti_ohci *)d->ohci;
	int i;

	ohci1394_stop_context(ohci, d->ctrlClear, NULL);

	for (i=0;i<d->num_desc;i++) {
		initialize_dma_ir_prg(d, i, flags);
		reset_ir_status(d, i);
	}

	/* reset the ctrl register */
	reg_write(ohci, d->ctrlClear, 0xf0000000);

	/* Set bufferFill */
	reg_write(ohci, d->ctrlSet, 0x80000000);

	/* Set isoch header */
	if (flags & VIDEO1394_INCLUDE_ISO_HEADERS) 
		reg_write(ohci, d->ctrlSet, 0x40000000);

	/* Set the context match register to match on all tags, 
	   sync for sync tag, and listen to d->channel */
	reg_write(ohci, d->ctxMatch, 0xf0000000|((tag&0xf)<<8)|d->channel);
	
	/* Set up isoRecvIntMask to generate interrupts */
	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1<<d->ctx);
}

/* find which context is listening to this channel */
int ir_ctx_listening(struct video_card *video, int channel)
{
	int i;
	struct ti_ohci *ohci = video->ohci;

	for (i=0;i<ohci->nb_iso_rcv_ctx-1;i++) 
		if (video->ir_context[i]) {
			if (video->ir_context[i]->channel==channel)
				return i;
		}
		
	PRINT(KERN_ERR, ohci->id, 
	      "no iso context is listening to channel %d",
	      channel);
	return -1;
}

int it_ctx_talking(struct video_card *video, int channel)
{
	int i;
	struct ti_ohci *ohci = video->ohci;

	for (i=0;i<ohci->nb_iso_xmit_ctx;i++) 
		if (video->it_context[i]) {
			if (video->it_context[i]->channel==channel)
				return i;
		}
		
	PRINT(KERN_ERR, ohci->id, 
	      "no iso context is talking to channel %d",
	      channel);
	return -1;
}

int wakeup_dma_ir_ctx(struct ti_ohci *ohci, struct dma_iso_ctx *d) 
{
	int i;

	if (d==NULL) {
		PRINT(KERN_ERR, ohci->id, "Iso receive event received but "
		      "context not allocated");
		return -EFAULT;
	}

	spin_lock(&d->lock);
	for (i=0;i<d->num_desc;i++) {
		if (d->ir_prg[i][d->nb_cmd-1].status & 0xFFFF0000) {
			reset_ir_status(d, i);
			d->buffer_status[i] = VIDEO1394_BUFFER_READY;
		}
	}
	spin_unlock(&d->lock);
	if (waitqueue_active(&d->waitq)) wake_up_interruptible(&d->waitq);
	return 0;
}

int wakeup_dma_it_ctx(struct ti_ohci *ohci, struct dma_iso_ctx *d) 
{
	int i;

	if (d==NULL) {
		PRINT(KERN_ERR, ohci->id, "Iso transmit event received but "
		      "context not allocated");
		return -EFAULT;
	}

	spin_lock(&d->lock);
	for (i=0;i<d->num_desc;i++) {
		if (d->it_prg[i][d->nb_cmd-1].end.status & 0xFFFF0000) {
			d->it_prg[i][d->nb_cmd-1].end.status = 0;
			d->buffer_status[i] = VIDEO1394_BUFFER_READY;
		}
	}
	spin_unlock(&d->lock);
	if (waitqueue_active(&d->waitq)) wake_up_interruptible(&d->waitq);
	return 0;
}

static void initialize_dma_it_prg(struct dma_iso_ctx *d, int n, int sync_tag)
{
	struct it_dma_prg *it_prg = d->it_prg[n];
	unsigned long buf = (unsigned long)d->buf+n*d->buf_size;
	int i;
	
	for (i=0;i<d->nb_cmd;i++) {
				 
		it_prg[i].begin.control = OUTPUT_MORE_IMMEDIATE | 8 ;
		it_prg[i].begin.address = 0;
		
		it_prg[i].begin.status = 0;
		
		/* FIXME: what is the tag value + speed selection */
		it_prg[i].data[0] = 
			(DMA_SPEED_400<<16) | (d->channel<<8) | 0xa0;
		if (i==0) it_prg[i].data[0] |= sync_tag;
		it_prg[i].data[1] = d->packet_size << 16;
		it_prg[i].data[2] = 0;
		it_prg[i].data[3] = 0;
		
		it_prg[i].end.control = 0x100c0000;
		it_prg[i].end.address =
			kvirt_to_bus(buf+i*d->packet_size);

		if (i<d->nb_cmd-1) {
			it_prg[i].end.control |= d->packet_size;
			it_prg[i].begin.branchAddress = 
				(virt_to_bus(&(it_prg[i+1].begin.control)) 
				 & 0xfffffff0) | 0x3;
			it_prg[i].end.branchAddress = 
				(virt_to_bus(&(it_prg[i+1].begin.control)) 
				 & 0xfffffff0) | 0x3;
		}
		else {
			/* the last prg generates an interrupt */
			it_prg[i].end.control |= 0x08300000 | d->left_size;
			/* the last prg doesn't branch */
			it_prg[i].begin.branchAddress = 0;
			it_prg[i].end.branchAddress = 0;
		}
		it_prg[i].end.status = 0;

#if 0
		printk("%d:%d: %08x-%08x ctrl %08x brch %08x d0 %08x d1 %08x\n",n,i,
		       virt_to_bus(&(it_prg[i].begin.control)),
		       virt_to_bus(&(it_prg[i].end.control)),
		       it_prg[i].end.control,
		       it_prg[i].end.branchAddress,
		       it_prg[i].data[0], it_prg[i].data[1]);
#endif
	}
}

static void initialize_dma_it_ctx(struct dma_iso_ctx *d, int sync_tag)
{
	struct ti_ohci *ohci = (struct ti_ohci *)d->ohci;
	int i;

	ohci1394_stop_context(ohci, d->ctrlClear, NULL);

	for (i=0;i<d->num_desc;i++)
		initialize_dma_it_prg(d, i, sync_tag);
	
	/* Set up isoRecvIntMask to generate interrupts */
	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1<<d->ctx);
}

static int do_iso_mmap(struct ti_ohci *ohci, struct dma_iso_ctx *d, 
		       const char *adr, unsigned long size)
{
        unsigned long start=(unsigned long) adr;
        unsigned long page,pos;

        if (size>d->num_desc * d->buf_size) {
		PRINT(KERN_ERR, ohci->id, 
		      "iso context %d buf size is different from mmap size", 
		      d->ctx);
                return -EINVAL;
	}
        if (!d->buf) {
		PRINT(KERN_ERR, ohci->id, 
		      "iso context %d is not allocated", d->ctx);
		return -EINVAL;
	}

        pos=(unsigned long) d->buf;
        while (size > 0) {
                page = kvirt_to_pa(pos);
                if (remap_page_range(start, page, PAGE_SIZE, PAGE_SHARED))
                        return -EAGAIN;
                start+=PAGE_SIZE;
                pos+=PAGE_SIZE;
                size-=PAGE_SIZE;
        }
        return 0;
}

static int video1394_ioctl(struct inode *inode, struct file *file,
			   unsigned int cmd, unsigned long arg)
{
	struct video_card *video = &video_cards[MINOR(inode->i_rdev)];
	struct ti_ohci *ohci= video->ohci;
	unsigned long flags;

	switch(cmd)
	{
	case VIDEO1394_LISTEN_CHANNEL:
	case VIDEO1394_TALK_CHANNEL:
	{
		struct video1394_mmap v;
		u64 mask;
		int i;

		if(copy_from_user(&v, (void *)arg, sizeof(v)))
			return -EFAULT;
		if (v.channel<0 || v.channel>(ISO_CHANNELS-1)) {
			PRINT(KERN_ERR, ohci->id, 
			      "iso channel %d out of bound", v.channel);
			return -EFAULT;
		}
		mask = (u64)0x1<<v.channel;
		printk("mask: %08X%08X usage: %08X%08X\n",
		       (u32)(mask>>32),(u32)(mask&0xffffffff),
		       (u32)(ohci->ISO_channel_usage>>32),
		       (u32)(ohci->ISO_channel_usage&0xffffffff));
		if (ohci->ISO_channel_usage & mask) {
			PRINT(KERN_ERR, ohci->id, 
			      "channel %d is already taken", v.channel);
			return -EFAULT;
		}
		ohci->ISO_channel_usage |= mask;
		
		if (v.buf_size<=0) {
			PRINT(KERN_ERR, ohci->id,
			      "Invalid %d length buffer requested",v.buf_size);
			return -EFAULT;
		}

		if (v.nb_buffers<=0) {
			PRINT(KERN_ERR, ohci->id,
			      "Invalid %d buffers requested",v.nb_buffers);
			return -EFAULT;
		}

		if (v.nb_buffers * v.buf_size > VIDEO1394_MAX_SIZE) {
			PRINT(KERN_ERR, ohci->id, 
			      "%d buffers of size %d bytes is too big", 
			      v.nb_buffers, v.buf_size);
			return -EFAULT;
		}

		if (cmd == VIDEO1394_LISTEN_CHANNEL) {
			/* find a free iso receive context */
			for (i=0;i<ohci->nb_iso_rcv_ctx-1;i++) 
				if (video->ir_context[i]==NULL) break;
			    
			if (i==(ohci->nb_iso_rcv_ctx-1)) {
				PRINT(KERN_ERR, ohci->id, 
				      "no iso context available");
				return -EFAULT;
			}

			video->ir_context[i] = 
				alloc_dma_iso_ctx(ohci, ISO_RECEIVE, i+1, 
						  v.nb_buffers, v.buf_size, 
						  v.channel, 0);

			if (video->ir_context[i] == NULL) {
				PRINT(KERN_ERR, ohci->id, 
				      "Couldn't allocate ir context");
				return -EFAULT;
			}
			initialize_dma_ir_ctx(video->ir_context[i], 
					      v.sync_tag, v.flags);

			video->current_ctx = video->ir_context[i];

			v.buf_size = video->ir_context[i]->buf_size;

			PRINT(KERN_INFO, ohci->id, 
			      "iso context %d listen on channel %d", i+1, 
			      v.channel);
		}
		else {
			/* find a free iso transmit context */
			for (i=0;i<ohci->nb_iso_xmit_ctx;i++) 
				if (video->it_context[i]==NULL) break;
			    
			if (i==ohci->nb_iso_xmit_ctx) {
				PRINT(KERN_ERR, ohci->id, 
				      "no iso context available");
				return -EFAULT;
			}
			
			video->it_context[i] = 
				alloc_dma_iso_ctx(ohci, ISO_TRANSMIT, i, 
						  v.nb_buffers, v.buf_size, 
						  v.channel, v.packet_size);

			if (video->it_context[i] == NULL) {
				PRINT(KERN_ERR, ohci->id, 
				      "Couldn't allocate it context");
				return -EFAULT;
			}
			initialize_dma_it_ctx(video->it_context[i], 
					      v.sync_tag);

			video->current_ctx = video->it_context[i];

			v.buf_size = video->it_context[i]->buf_size;

			PRINT(KERN_INFO, ohci->id, 
			      "iso context %d talk on channel %d", i, 
			      v.channel);
		}

		if(copy_to_user((void *)arg, &v, sizeof(v)))
			return -EFAULT;

		return 0;
	}
	case VIDEO1394_UNLISTEN_CHANNEL: 
	case VIDEO1394_UNTALK_CHANNEL:
	{
		int channel;
		u64 mask;
		int i;

		if(copy_from_user(&channel, (void *)arg, sizeof(int)))
			return -EFAULT;

		if (channel<0 || channel>(ISO_CHANNELS-1)) {
			PRINT(KERN_ERR, ohci->id, 
			      "iso channel %d out of bound", channel);
			return -EFAULT;
		}
		mask = (u64)0x1<<channel;
		if (!(ohci->ISO_channel_usage & mask)) {
			PRINT(KERN_ERR, ohci->id, 
			      "channel %d is not being used", channel);
			return -EFAULT;
		}
		ohci->ISO_channel_usage &= ~mask;

		if (cmd == VIDEO1394_UNLISTEN_CHANNEL) {
			i = ir_ctx_listening(video, channel);
			if (i<0) return -EFAULT;

			free_dma_iso_ctx(&video->ir_context[i]);

			PRINT(KERN_INFO, ohci->id, 
			      "iso context %d stop listening on channel %d", 
			      i+1, channel);
		}
		else {
			i = it_ctx_talking(video, channel);
			if (i<0) return -EFAULT;

			free_dma_iso_ctx(&video->it_context[i]);

			PRINT(KERN_INFO, ohci->id, 
			      "iso context %d stop talking on channel %d", 
			      i, channel);
		}
		
		return 0;
	}
	case VIDEO1394_LISTEN_QUEUE_BUFFER:
	{
		struct video1394_wait v;
		struct dma_iso_ctx *d;
		int i;

		if(copy_from_user(&v, (void *)arg, sizeof(v)))
			return -EFAULT;

		i = ir_ctx_listening(video, v.channel);
		if (i<0) return -EFAULT;
		d = video->ir_context[i];

		if ((v.buffer<0) || (v.buffer>d->num_desc)) {
			PRINT(KERN_ERR, ohci->id, 
			      "buffer %d out of range",v.buffer);
			return -EFAULT;
		}
		
		spin_lock_irqsave(&d->lock,flags);

		if (d->buffer_status[v.buffer]==VIDEO1394_BUFFER_QUEUED) {
			PRINT(KERN_ERR, ohci->id, 
			      "buffer %d is already used",v.buffer);
			spin_unlock_irqrestore(&d->lock,flags);
			return -EFAULT;
		}
		
		d->buffer_status[v.buffer]=VIDEO1394_BUFFER_QUEUED;

		if (d->last_buffer>=0) 
			d->ir_prg[d->last_buffer][d->nb_cmd-1].branchAddress = 
				(virt_to_bus(&(d->ir_prg[v.buffer][0].control)) 
				 & 0xfffffff0) | 0x1;

		d->last_buffer = v.buffer;

		d->ir_prg[d->last_buffer][d->nb_cmd-1].branchAddress = 0;

		spin_unlock_irqrestore(&d->lock,flags);

		if (!(reg_read(ohci, d->ctrlSet) & 0x8000)) 
		{
			DBGMSG(ohci->id, "Starting iso DMA ctx=%d",d->ctx);

			/* Tell the controller where the first program is */