fw-transaction.c

linux 内核源代码

 * deallocated region, payload is set to NULL.
 */
void fw_core_remove_address_handler(struct fw_address_handler *handler)
{
	unsigned long flags;

	spin_lock_irqsave(&address_handler_lock, flags);
	list_del(&handler->link);
	spin_unlock_irqrestore(&address_handler_lock, flags);
}
EXPORT_SYMBOL(fw_core_remove_address_handler);

struct fw_request {
	struct fw_packet response;
	u32 request_header[4];
	int ack;
	u32 length;
	u32 data[0];
};

static void
free_response_callback(struct fw_packet *packet,
		       struct fw_card *card, int status)
{
	struct fw_request *request;

	request = container_of(packet, struct fw_request, response);
	kfree(request);
}

void
fw_fill_response(struct fw_packet *response, u32 *request_header,
		 int rcode, void *payload, size_t length)
{
	int tcode, tlabel, extended_tcode, source, destination;

	tcode          = HEADER_GET_TCODE(request_header[0]);
	tlabel         = HEADER_GET_TLABEL(request_header[0]);
	source         = HEADER_GET_DESTINATION(request_header[0]);
	destination    = HEADER_GET_SOURCE(request_header[1]);
	extended_tcode = HEADER_GET_EXTENDED_TCODE(request_header[3]);

	response->header[0] =
		HEADER_RETRY(RETRY_1) |
		HEADER_TLABEL(tlabel) |
		HEADER_DESTINATION(destination);
	response->header[1] =
		HEADER_SOURCE(source) |
		HEADER_RCODE(rcode);
	response->header[2] = 0;

	switch (tcode) {
	case TCODE_WRITE_QUADLET_REQUEST:
	case TCODE_WRITE_BLOCK_REQUEST:
		response->header[0] |= HEADER_TCODE(TCODE_WRITE_RESPONSE);
		response->header_length = 12;
		response->payload_length = 0;
		break;

	case TCODE_READ_QUADLET_REQUEST:
		response->header[0] |=
			HEADER_TCODE(TCODE_READ_QUADLET_RESPONSE);
		if (payload != NULL)
			response->header[3] = *(u32 *)payload;
		else
			response->header[3] = 0;
		response->header_length = 16;
		response->payload_length = 0;
		break;

	case TCODE_READ_BLOCK_REQUEST:
	case TCODE_LOCK_REQUEST:
		response->header[0] |= HEADER_TCODE(tcode + 2);
		response->header[3] =
			HEADER_DATA_LENGTH(length) |
			HEADER_EXTENDED_TCODE(extended_tcode);
		response->header_length = 16;
		response->payload = payload;
		response->payload_length = length;
		break;

	default:
		BUG();
		return;
	}
}
EXPORT_SYMBOL(fw_fill_response);

static struct fw_request *
allocate_request(struct fw_packet *p)
{
	struct fw_request *request;
	u32 *data, length;
	int request_tcode, t;

	request_tcode = HEADER_GET_TCODE(p->header[0]);
	switch (request_tcode) {
	case TCODE_WRITE_QUADLET_REQUEST:
		data = &p->header[3];
		length = 4;
		break;

	case TCODE_WRITE_BLOCK_REQUEST:
	case TCODE_LOCK_REQUEST:
		data = p->payload;
		length = HEADER_GET_DATA_LENGTH(p->header[3]);
		break;

	case TCODE_READ_QUADLET_REQUEST:
		data = NULL;
		length = 4;
		break;

	case TCODE_READ_BLOCK_REQUEST:
		data = NULL;
		length = HEADER_GET_DATA_LENGTH(p->header[3]);
		break;

	default:
		BUG();
		return NULL;
	}

	request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
	if (request == NULL)
		return NULL;

	t = (p->timestamp & 0x1fff) + 4000;
	if (t >= 8000)
		t = (p->timestamp & ~0x1fff) + 0x2000 + t - 8000;
	else
		t = (p->timestamp & ~0x1fff) + t;

	request->response.speed = p->speed;
	request->response.timestamp = t;
	request->response.generation = p->generation;
	request->response.ack = 0;
	request->response.callback = free_response_callback;
	request->ack = p->ack;
	request->length = length;
	if (data)
		memcpy(request->data, data, length);

	memcpy(request->request_header, p->header, sizeof(p->header));

	return request;
}

void
fw_send_response(struct fw_card *card, struct fw_request *request, int rcode)
{
	/*
	 * Broadcast packets are reported as ACK_COMPLETE, so this
	 * check is sufficient to ensure we don't send response to
	 * broadcast packets or posted writes.
	 */
	if (request->ack != ACK_PENDING) {
		kfree(request);
		return;
	}

	if (rcode == RCODE_COMPLETE)
		fw_fill_response(&request->response, request->request_header,
				 rcode, request->data, request->length);
	else
		fw_fill_response(&request->response, request->request_header,
				 rcode, NULL, 0);

	card->driver->send_response(card, &request->response);
}
EXPORT_SYMBOL(fw_send_response);

void
fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
{
	struct fw_address_handler *handler;
	struct fw_request *request;
	unsigned long long offset;
	unsigned long flags;
	int tcode, destination, source;

	if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
		return;

	request = allocate_request(p);
	if (request == NULL) {
		/* FIXME: send statically allocated busy packet. */
		return;
	}

	offset      =
		((unsigned long long)
		 HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) | p->header[2];
	tcode       = HEADER_GET_TCODE(p->header[0]);
	destination = HEADER_GET_DESTINATION(p->header[0]);
	source      = HEADER_GET_SOURCE(p->header[0]);

	spin_lock_irqsave(&address_handler_lock, flags);
	handler = lookup_enclosing_address_handler(&address_handler_list,
						   offset, request->length);
	spin_unlock_irqrestore(&address_handler_lock, flags);

	/*
	 * FIXME: lookup the fw_node corresponding to the sender of
	 * this request and pass that to the address handler instead
	 * of the node ID.  We may also want to move the address
	 * allocations to fw_node so we only do this callback if the
	 * upper layers registered it for this node.
	 */

	if (handler == NULL)
		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
	else
		handler->address_callback(card, request,
					  tcode, destination, source,
					  p->generation, p->speed, offset,
					  request->data, request->length,
					  handler->callback_data);
}
EXPORT_SYMBOL(fw_core_handle_request);

void
fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
{
	struct fw_transaction *t;
	unsigned long flags;
	u32 *data;
	size_t data_length;
	int tcode, tlabel, destination, source, rcode;

	tcode       = HEADER_GET_TCODE(p->header[0]);
	tlabel      = HEADER_GET_TLABEL(p->header[0]);
	destination = HEADER_GET_DESTINATION(p->header[0]);
	source      = HEADER_GET_SOURCE(p->header[1]);
	rcode       = HEADER_GET_RCODE(p->header[1]);

	spin_lock_irqsave(&card->lock, flags);
	list_for_each_entry(t, &card->transaction_list, link) {
		if (t->node_id == source && t->tlabel == tlabel) {
			list_del(&t->link);
			card->tlabel_mask &= ~(1 << t->tlabel);
			break;
		}
	}
	spin_unlock_irqrestore(&card->lock, flags);

	if (&t->link == &card->transaction_list) {
		fw_notify("Unsolicited response (source %x, tlabel %x)\n",
			  source, tlabel);
		return;
	}

	/*
	 * FIXME: sanity check packet, is length correct, does tcodes
	 * and addresses match.
	 */

	switch (tcode) {
	case TCODE_READ_QUADLET_RESPONSE:
		data = (u32 *) &p->header[3];
		data_length = 4;
		break;

	case TCODE_WRITE_RESPONSE:
		data = NULL;
		data_length = 0;
		break;

	case TCODE_READ_BLOCK_RESPONSE:
	case TCODE_LOCK_RESPONSE:
		data = p->payload;
		data_length = HEADER_GET_DATA_LENGTH(p->header[3]);
		break;

	default:
		/* Should never happen, this is just to shut up gcc. */
		data = NULL;
		data_length = 0;
		break;
	}

	t->callback(card, rcode, data, data_length, t->callback_data);
}
EXPORT_SYMBOL(fw_core_handle_response);

static const struct fw_address_region topology_map_region =
	{ .start = 0xfffff0001000ull, .end = 0xfffff0001400ull, };

static void
handle_topology_map(struct fw_card *card, struct fw_request *request,
		    int tcode, int destination, int source,
		    int generation, int speed,
		    unsigned long long offset,
		    void *payload, size_t length, void *callback_data)
{
	int i, start, end;
	u32 *map;

	if (!TCODE_IS_READ_REQUEST(tcode)) {
		fw_send_response(card, request, RCODE_TYPE_ERROR);
		return;
	}

	if ((offset & 3) > 0 || (length & 3) > 0) {
		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
		return;
	}

	start = (offset - topology_map_region.start) / 4;
	end = start + length / 4;
	map = payload;

	for (i = 0; i < length / 4; i++)
		map[i] = cpu_to_be32(card->topology_map[start + i]);

	fw_send_response(card, request, RCODE_COMPLETE);
}

static struct fw_address_handler topology_map = {
	.length			= 0x200,
	.address_callback	= handle_topology_map,
};

static const struct fw_address_region registers_region =
	{ .start = 0xfffff0000000ull, .end = 0xfffff0000400ull, };

static void
handle_registers(struct fw_card *card, struct fw_request *request,
		 int tcode, int destination, int source,
		 int generation, int speed,
		 unsigned long long offset,
		 void *payload, size_t length, void *callback_data)
{
	int reg = offset - CSR_REGISTER_BASE;
	unsigned long long bus_time;
	__be32 *data = payload;

	switch (reg) {
	case CSR_CYCLE_TIME:
	case CSR_BUS_TIME:
		if (!TCODE_IS_READ_REQUEST(tcode) || length != 4) {
			fw_send_response(card, request, RCODE_TYPE_ERROR);
			break;
		}

		bus_time = card->driver->get_bus_time(card);
		if (reg == CSR_CYCLE_TIME)
			*data = cpu_to_be32(bus_time);
		else
			*data = cpu_to_be32(bus_time >> 25);
		fw_send_response(card, request, RCODE_COMPLETE);
		break;

	case CSR_BUS_MANAGER_ID:
	case CSR_BANDWIDTH_AVAILABLE:
	case CSR_CHANNELS_AVAILABLE_HI:
	case CSR_CHANNELS_AVAILABLE_LO:
		/*
		 * FIXME: these are handled by the OHCI hardware and
		 * the stack never sees these request. If we add
		 * support for a new type of controller that doesn't
		 * handle this in hardware we need to deal with these
		 * transactions.
		 */
		BUG();
		break;

	case CSR_BUSY_TIMEOUT:
		/* FIXME: Implement this. */
	default:
		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
		break;
	}
}

static struct fw_address_handler registers = {
	.length			= 0x400,
	.address_callback	= handle_registers,
};

MODULE_AUTHOR("Kristian Hoegsberg <[e-mail]>");
MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
MODULE_LICENSE("GPL");

static const u32 vendor_textual_descriptor[] = {
	/* textual descriptor leaf () */
	0x00060000,
	0x00000000,
	0x00000000,
	0x4c696e75,		/* L i n u */
	0x78204669,		/* x   F i */
	0x72657769,		/* r e w i */
	0x72650000,		/* r e     */
};

static const u32 model_textual_descriptor[] = {
	/* model descriptor leaf () */
	0x00030000,
	0x00000000,
	0x00000000,
	0x4a756a75,		/* J u j u */
};

static struct fw_descriptor vendor_id_descriptor = {
	.length = ARRAY_SIZE(vendor_textual_descriptor),
	.immediate = 0x03d00d1e,
	.key = 0x81000000,
	.data = vendor_textual_descriptor,
};

static struct fw_descriptor model_id_descriptor = {
	.length = ARRAY_SIZE(model_textual_descriptor),
	.immediate = 0x17000001,
	.key = 0x81000000,
	.data = model_textual_descriptor,
};

static int __init fw_core_init(void)
{
	int retval;

	retval = bus_register(&fw_bus_type);
	if (retval < 0)
		return retval;

	fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
	if (fw_cdev_major < 0) {
		bus_unregister(&fw_bus_type);
		return fw_cdev_major;
	}

	retval = fw_core_add_address_handler(&topology_map,
					     &topology_map_region);
	BUG_ON(retval < 0);

	retval = fw_core_add_address_handler(&registers,
					     &registers_region);
	BUG_ON(retval < 0);

	/* Add the vendor textual descriptor. */
	retval = fw_core_add_descriptor(&vendor_id_descriptor);
	BUG_ON(retval < 0);
	retval = fw_core_add_descriptor(&model_id_descriptor);
	BUG_ON(retval < 0);

	return 0;
}

static void __exit fw_core_cleanup(void)
{
	unregister_chrdev(fw_cdev_major, "firewire");
	bus_unregister(&fw_bus_type);
}

module_init(fw_core_init);
module_exit(fw_core_cleanup);