ieee1394_core.c

Ieee1394驱动实现

			HPSB_NOTICE("Stopping out-of-control reset loop");
			HPSB_NOTICE("Warning - topology map and speed map will not be valid");
			host->reset_retries = 0;
		}
	} else {
		host->reset_retries = 0;
		build_speed_map(host, host->node_count);
	}

	HPSB_VERBOSE("selfid_complete called with successful SelfID stage "
		     "... irm_id: 0x%X node_id: 0x%X",host->irm_id,host->node_id);

	/* irm_id is kept up to date by check_selfids() */
	if (host->irm_id == host->node_id) {
		host->is_irm = 1;
	} else {
		host->is_busmgr = 0;
		host->is_irm = 0;
	}

	if (isroot) {
		host->driver->devctl(host, ACT_CYCLE_MASTER, 1);
		host->is_cycmst = 1;
	}
	atomic_inc(&host->generation);
	host->in_bus_reset = 0;
	highlevel_host_reset(host);
}

static spinlock_t pending_packets_lock = SPIN_LOCK_UNLOCKED;

/**
 * hpsb_packet_sent - notify core of sending a packet
 *
 * For host driver module usage.  Safe to call from within a transmit packet
 * routine.
 *
 * Notify core of sending a packet.  Ackcode is the ack code returned for async
 * transmits or ACKX_SEND_ERROR if the transmission failed completely; ACKX_NONE
 * for other cases (internal errors that don't justify a panic).
 */
void hpsb_packet_sent(struct hpsb_host *host, struct hpsb_packet *packet,
		      int ackcode)
{
	unsigned long flags;

	spin_lock_irqsave(&pending_packets_lock, flags);

	packet->ack_code = ackcode;

	if (packet->no_waiter || packet->state == hpsb_complete) {
		/* if packet->no_waiter, must not have a tlabel allocated */
		spin_unlock_irqrestore(&pending_packets_lock, flags);
		hpsb_free_packet(packet);
		return;
	}

	atomic_dec(&packet->refcnt);	/* drop HC's reference */
	/* here the packet must be on the host->pending_packets queue */

	if (ackcode != ACK_PENDING || !packet->expect_response) {
		packet->state = hpsb_complete;
		list_del_init(&packet->queue);
		spin_unlock_irqrestore(&pending_packets_lock, flags);
		queue_packet_complete(packet);
		return;
	}

	packet->state = hpsb_pending;
	packet->sendtime = jiffies;

	spin_unlock_irqrestore(&pending_packets_lock, flags);

	mod_timer(&host->timeout, jiffies + host->timeout_interval);
}

/**
 * hpsb_send_phy_config - transmit a PHY configuration packet on the bus
 * @host: host that PHY config packet gets sent through
 * @rootid: root whose force_root bit should get set (-1 = don't set force_root)
 * @gapcnt: gap count value to set (-1 = don't set gap count)
 *
 * This function sends a PHY config packet on the bus through the specified
 * host.
 *
 * Return value: 0 for success or negative error number otherwise.
 */
int hpsb_send_phy_config(struct hpsb_host *host, int rootid, int gapcnt)
{
	struct hpsb_packet *packet;
	quadlet_t d = 0;
	int retval = 0;

	if (rootid >= ALL_NODES || rootid < -1 || gapcnt > 0x3f || gapcnt < -1 ||
	   (rootid == -1 && gapcnt == -1)) {
		HPSB_DEBUG("Invalid Parameter: rootid = %d   gapcnt = %d",
			   rootid, gapcnt);
		return -EINVAL;
	}

	if (rootid != -1)
		d |= PHYPACKET_PHYCONFIG_R | rootid << PHYPACKET_PORT_SHIFT;
	if (gapcnt != -1)
		d |= PHYPACKET_PHYCONFIG_T | gapcnt << PHYPACKET_GAPCOUNT_SHIFT;

	packet = hpsb_make_phypacket(host, d);
	if (!packet)
		return -ENOMEM;

	packet->generation = get_hpsb_generation(host);
	retval = hpsb_send_packet_and_wait(packet);
	hpsb_free_packet(packet);

	return retval;
}

/**
 * hpsb_send_packet - transmit a packet on the bus
 * @packet: packet to send
 *
 * The packet is sent through the host specified in the packet->host field.
 * Before sending, the packet's transmit speed is automatically determined
 * using the local speed map when it is an async, non-broadcast packet.
 *
 * Possibilities for failure are that host is either not initialized, in bus
 * reset, the packet's generation number doesn't match the current generation
 * number or the host reports a transmit error.
 *
 * Return value: 0 on success, negative errno on failure.
 */
int hpsb_send_packet(struct hpsb_packet *packet)
{
	struct hpsb_host *host = packet->host;

	if (host->is_shutdown)
		return -EINVAL;
	if (host->in_bus_reset ||
	    (packet->generation != get_hpsb_generation(host)))
		return -EAGAIN;

	packet->state = hpsb_queued;

	/* This just seems silly to me */
	WARN_ON(packet->no_waiter && packet->expect_response);

	if (!packet->no_waiter || packet->expect_response) {
		unsigned long flags;

		atomic_inc(&packet->refcnt);
		/* Set the initial "sendtime" to 10 seconds from now, to
		   prevent premature expiry.  If a packet takes more than
		   10 seconds to hit the wire, we have bigger problems :) */
		packet->sendtime = jiffies + 10 * HZ;
		spin_lock_irqsave(&pending_packets_lock, flags);
		list_add_tail(&packet->queue, &host->pending_packets);
		spin_unlock_irqrestore(&pending_packets_lock, flags);
	}

	if (packet->node_id == host->node_id) {
		/* it is a local request, so handle it locally */

		quadlet_t *data;
		size_t size = packet->data_size + packet->header_size;

		data = kmalloc(size, GFP_ATOMIC);
		if (!data) {
			HPSB_ERR("unable to allocate memory for concatenating header and data");
			return -ENOMEM;
		}

		memcpy(data, packet->header, packet->header_size);

		if (packet->data_size)
			memcpy(((u8*)data) + packet->header_size, packet->data, packet->data_size);

		dump_packet("send packet local", packet->header, packet->header_size, -1);

		hpsb_packet_sent(host, packet, packet->expect_response ? ACK_PENDING : ACK_COMPLETE);
		hpsb_packet_received(host, data, size, 0);

		kfree(data);

		return 0;
	}

	if (packet->type == hpsb_async &&
	    NODEID_TO_NODE(packet->node_id) != ALL_NODES)
		packet->speed_code =
			host->speed[NODEID_TO_NODE(packet->node_id)];

	dump_packet("send packet", packet->header, packet->header_size, packet->speed_code);

	return host->driver->transmit_packet(host, packet);
}

/* We could just use complete() directly as the packet complete
 * callback, but this is more typesafe, in the sense that we get a
 * compiler error if the prototype for complete() changes. */

static void complete_packet(void *data)
{
	complete((struct completion *) data);
}

/**
 * hpsb_send_packet_and_wait - enqueue packet, block until transaction completes
 * @packet: packet to send
 *
 * Return value: 0 on success, negative errno on failure.
 */
int hpsb_send_packet_and_wait(struct hpsb_packet *packet)
{
	struct completion done;
	int retval;

	init_completion(&done);
	hpsb_set_packet_complete_task(packet, complete_packet, &done);
	retval = hpsb_send_packet(packet);
	if (retval == 0)
		wait_for_completion(&done);

	return retval;
}

static void send_packet_nocare(struct hpsb_packet *packet)
{
	if (hpsb_send_packet(packet) < 0) {
		hpsb_free_packet(packet);
	}
}

static size_t packet_size_to_data_size(size_t packet_size, size_t header_size,
				       size_t buffer_size, int tcode)
{
	size_t ret = packet_size <= header_size ? 0 : packet_size - header_size;

	if (unlikely(ret > buffer_size))
		ret = buffer_size;

	if (unlikely(ret + header_size != packet_size))
		HPSB_ERR("unexpected packet size %zd (tcode %d), bug?",
			 packet_size, tcode);
	return ret;
}

static void handle_packet_response(struct hpsb_host *host, int tcode,
				   quadlet_t *data, size_t size)
{
	struct hpsb_packet *packet;
	int tlabel = (data[0] >> 10) & 0x3f;
	size_t header_size;
	unsigned long flags;

	spin_lock_irqsave(&pending_packets_lock, flags);

	list_for_each_entry(packet, &host->pending_packets, queue)
		if (packet->tlabel == tlabel &&
		    packet->node_id == (data[1] >> 16))
			goto found;

	spin_unlock_irqrestore(&pending_packets_lock, flags);
	HPSB_DEBUG("unsolicited response packet received - %s",
		   "no tlabel match");
	dump_packet("contents", data, 16, -1);
	return;

found:
	switch (packet->tcode) {
	case TCODE_WRITEQ:
	case TCODE_WRITEB:
		if (unlikely(tcode != TCODE_WRITE_RESPONSE))
			break;
		header_size = 12;
		size = 0;
		goto dequeue;

	case TCODE_READQ:
		if (unlikely(tcode != TCODE_READQ_RESPONSE))
			break;
		header_size = 16;
		size = 0;
		goto dequeue;

	case TCODE_READB:
		if (unlikely(tcode != TCODE_READB_RESPONSE))
			break;
		header_size = 16;
		size = packet_size_to_data_size(size, header_size,
						packet->allocated_data_size,
						tcode);
		goto dequeue;

	case TCODE_LOCK_REQUEST:
		if (unlikely(tcode != TCODE_LOCK_RESPONSE))
			break;
		header_size = 16;
		size = packet_size_to_data_size(min(size, (size_t)(16 + 8)),
						header_size,
						packet->allocated_data_size,
						tcode);
		goto dequeue;
	}

	spin_unlock_irqrestore(&pending_packets_lock, flags);
	HPSB_DEBUG("unsolicited response packet received - %s",
		   "tcode mismatch");
	dump_packet("contents", data, 16, -1);
	return;

dequeue:
	list_del_init(&packet->queue);
	spin_unlock_irqrestore(&pending_packets_lock, flags);

	if (packet->state == hpsb_queued) {
		packet->sendtime = jiffies;
		packet->ack_code = ACK_PENDING;
	}
	packet->state = hpsb_complete;

	memcpy(packet->header, data, header_size);
	if (size)
		memcpy(packet->data, data + 4, size);

	queue_packet_complete(packet);
}


static struct hpsb_packet *create_reply_packet(struct hpsb_host *host,
					       quadlet_t *data, size_t dsize)
{
	struct hpsb_packet *p;

	p = hpsb_alloc_packet(dsize);
	if (unlikely(p == NULL)) {
		/* FIXME - send data_error response */
		HPSB_ERR("out of memory, cannot send response packet");
		return NULL;
	}

	p->type = hpsb_async;
	p->state = hpsb_unused;
	p->host = host;
	p->node_id = data[1] >> 16;
	p->tlabel = (data[0] >> 10) & 0x3f;
	p->no_waiter = 1;

	p->generation = get_hpsb_generation(host);

	if (dsize % 4)
		p->data[dsize / 4] = 0;

	return p;
}

#define PREP_ASYNC_HEAD_RCODE(tc) \
	packet->tcode = tc; \
	packet->header[0] = (packet->node_id << 16) | (packet->tlabel << 10) \
		| (1 << 8) | (tc << 4); \
	packet->header[1] = (packet->host->node_id << 16) | (rcode << 12); \
	packet->header[2] = 0

static void fill_async_readquad_resp(struct hpsb_packet *packet, int rcode,
			      quadlet_t data)
{
	PREP_ASYNC_HEAD_RCODE(TCODE_READQ_RESPONSE);
	packet->header[3] = data;
	packet->header_size = 16;
	packet->data_size = 0;
}

static void fill_async_readblock_resp(struct hpsb_packet *packet, int rcode,
			       int length)
{
	if (rcode != RCODE_COMPLETE)
		length = 0;

	PREP_ASYNC_HEAD_RCODE(TCODE_READB_RESPONSE);
	packet->header[3] = length << 16;
	packet->header_size = 16;
	packet->data_size = length + (length % 4 ? 4 - (length % 4) : 0);
}

static void fill_async_write_resp(struct hpsb_packet *packet, int rcode)
{
	PREP_ASYNC_HEAD_RCODE(TCODE_WRITE_RESPONSE);
	packet->header_size = 12;
	packet->data_size = 0;
}

static void fill_async_lock_resp(struct hpsb_packet *packet, int rcode, int extcode,
			  int length)
{
	if (rcode != RCODE_COMPLETE)
		length = 0;

	PREP_ASYNC_HEAD_RCODE(TCODE_LOCK_RESPONSE);
	packet->header[3] = (length << 16) | extcode;
	packet->header_size = 16;
	packet->data_size = length;
}

static void handle_incoming_packet(struct hpsb_host *host, int tcode,
				   quadlet_t *data, size_t size,
				   int write_acked)
{
	struct hpsb_packet *packet;
	int length, rcode, extcode;
	quadlet_t buffer;
	nodeid_t source = data[1] >> 16;
	nodeid_t dest = data[0] >> 16;
	u16 flags = (u16) data[0];
	u64 addr;

	/* FIXME?
	 * Out-of-bounds lengths are left for highlevel_read|write to cap. */

	switch (tcode) {
	case TCODE_WRITEQ:
		addr = (((u64)(data[1] & 0xffff)) << 32) | data[2];
		rcode = highlevel_write(host, source, dest, data + 3,
					addr, 4, flags);
		goto handle_write_request;

	case TCODE_WRITEB:
		addr = (((u64)(data[1] & 0xffff)) << 32) | data[2];
		rcode = highlevel_write(host, source, dest, data + 4,
					addr, data[3] >> 16, flags);
handle_write_request:
		if (rcode < 0 || write_acked ||
		    NODEID_TO_NODE(data[0] >> 16) == NODE_MASK)
			return;
		/* not a broadcast write, reply */
		packet = create_reply_packet(host, data, 0);
		if (packet) {
			fill_async_write_resp(packet, rcode);
			send_packet_nocare(packet);
		}
		return;

	case TCODE_READQ:
		addr = (((u64)(data[1] & 0xffff)) << 32) | data[2];
		rcode = highlevel_read(host, source, &buffer, addr, 4, flags);
		if (rcode < 0)
			return;

		packet = create_reply_packet(host, data, 0);
		if (packet) {
			fill_async_readquad_resp(packet, rcode, buffer);
			send_packet_nocare(packet);
		}
		return;

	case TCODE_READB:
		length = data[3] >> 16;
		packet = create_reply_packet(host, data, length);
		if (!packet)
			return;

		addr = (((u64)(data[1] & 0xffff)) << 32) | data[2];
		rcode = highlevel_read(host, source, packet->data, addr,