Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1302 insertions, 0 deletions

diff --git a/drivers/firewire/core-transaction.c b/drivers/firewire/core-transaction.c
new file mode 100644
index 000000000..ce764bebb
--- /dev/null
+++ b/drivers/firewire/core-transaction.c
@@ -0,0 +1,1302 @@
+/*
+ * Core IEEE1394 transaction logic
+ *
+ * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <linux/bug.h>
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/firewire.h>
+#include <linux/firewire-constants.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/idr.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/rculist.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+
+#include <asm/byteorder.h>
+
+#include "core.h"
+
+#define HEADER_PRI(pri)			((pri) << 0)
+#define HEADER_TCODE(tcode)		((tcode) << 4)
+#define HEADER_RETRY(retry)		((retry) << 8)
+#define HEADER_TLABEL(tlabel)		((tlabel) << 10)
+#define HEADER_DESTINATION(destination)	((destination) << 16)
+#define HEADER_SOURCE(source)		((source) << 16)
+#define HEADER_RCODE(rcode)		((rcode) << 12)
+#define HEADER_OFFSET_HIGH(offset_high)	((offset_high) << 0)
+#define HEADER_DATA_LENGTH(length)	((length) << 16)
+#define HEADER_EXTENDED_TCODE(tcode)	((tcode) << 0)
+
+#define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
+#define HEADER_GET_TLABEL(q)		(((q) >> 10) & 0x3f)
+#define HEADER_GET_RCODE(q)		(((q) >> 12) & 0x0f)
+#define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
+#define HEADER_GET_SOURCE(q)		(((q) >> 16) & 0xffff)
+#define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
+#define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
+#define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)
+
+#define HEADER_DESTINATION_IS_BROADCAST(q) \
+	(((q) & HEADER_DESTINATION(0x3f)) == HEADER_DESTINATION(0x3f))
+
+#define PHY_PACKET_CONFIG	0x0
+#define PHY_PACKET_LINK_ON	0x1
+#define PHY_PACKET_SELF_ID	0x2
+
+#define PHY_CONFIG_GAP_COUNT(gap_count)	(((gap_count) << 16) | (1 << 22))
+#define PHY_CONFIG_ROOT_ID(node_id)	((((node_id) & 0x3f) << 24) | (1 << 23))
+#define PHY_IDENTIFIER(id)		((id) << 30)
+
+/* returns 0 if the split timeout handler is already running */
+static int try_cancel_split_timeout(struct fw_transaction *t)
+{
+	if (t->is_split_transaction)
+		return del_timer(&t->split_timeout_timer);
+	else
+		return 1;
+}
+
+static int close_transaction(struct fw_transaction *transaction,
+			     struct fw_card *card, int rcode)
+{
+	struct fw_transaction *t = NULL, *iter;
+	unsigned long flags;
+
+	spin_lock_irqsave(&card->lock, flags);
+	list_for_each_entry(iter, &card->transaction_list, link) {
+		if (iter == transaction) {
+			if (!try_cancel_split_timeout(iter)) {
+				spin_unlock_irqrestore(&card->lock, flags);
+				goto timed_out;
+			}
+			list_del_init(&iter->link);
+			card->tlabel_mask &= ~(1ULL << iter->tlabel);
+			t = iter;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&card->lock, flags);
+
+	if (t) {
+		t->callback(card, rcode, NULL, 0, t->callback_data);
+		return 0;
+	}
+
+ timed_out:
+	return -ENOENT;
+}
+
+/*
+ * Only valid for transactions that are potentially pending (ie have
+ * been sent).
+ */
+int fw_cancel_transaction(struct fw_card *card,
+			  struct fw_transaction *transaction)
+{
+	/*
+	 * Cancel the packet transmission if it's still queued.  That
+	 * will call the packet transmission callback which cancels
+	 * the transaction.
+	 */
+
+	if (card->driver->cancel_packet(card, &transaction->packet) == 0)
+		return 0;
+
+	/*
+	 * If the request packet has already been sent, we need to see
+	 * if the transaction is still pending and remove it in that case.
+	 */
+
+	return close_transaction(transaction, card, RCODE_CANCELLED);
+}
+EXPORT_SYMBOL(fw_cancel_transaction);
+
+static void split_transaction_timeout_callback(struct timer_list *timer)
+{
+	struct fw_transaction *t = from_timer(t, timer, split_timeout_timer);
+	struct fw_card *card = t->card;
+	unsigned long flags;
+
+	spin_lock_irqsave(&card->lock, flags);
+	if (list_empty(&t->link)) {
+		spin_unlock_irqrestore(&card->lock, flags);
+		return;
+	}
+	list_del(&t->link);
+	card->tlabel_mask &= ~(1ULL << t->tlabel);
+	spin_unlock_irqrestore(&card->lock, flags);
+
+	t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
+}
+
+static void start_split_transaction_timeout(struct fw_transaction *t,
+					    struct fw_card *card)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&card->lock, flags);
+
+	if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
+		spin_unlock_irqrestore(&card->lock, flags);
+		return;
+	}
+
+	t->is_split_transaction = true;
+	mod_timer(&t->split_timeout_timer,
+		  jiffies + card->split_timeout_jiffies);
+
+	spin_unlock_irqrestore(&card->lock, flags);
+}
+
+static void transmit_complete_callback(struct fw_packet *packet,
+				       struct fw_card *card, int status)
+{
+	struct fw_transaction *t =
+	    container_of(packet, struct fw_transaction, packet);
+
+	switch (status) {
+	case ACK_COMPLETE:
+		close_transaction(t, card, RCODE_COMPLETE);
+		break;
+	case ACK_PENDING:
+		start_split_transaction_timeout(t, card);
+		break;
+	case ACK_BUSY_X:
+	case ACK_BUSY_A:
+	case ACK_BUSY_B:
+		close_transaction(t, card, RCODE_BUSY);
+		break;
+	case ACK_DATA_ERROR:
+		close_transaction(t, card, RCODE_DATA_ERROR);
+		break;
+	case ACK_TYPE_ERROR:
+		close_transaction(t, card, RCODE_TYPE_ERROR);
+		break;
+	default:
+		/*
+		 * In this case the ack is really a juju specific
+		 * rcode, so just forward that to the callback.
+		 */
+		close_transaction(t, card, status);
+		break;
+	}
+}
+
+static void fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
+		int destination_id, int source_id, int generation, int speed,
+		unsigned long long offset, void *payload, size_t length)
+{
+	int ext_tcode;
+
+	if (tcode == TCODE_STREAM_DATA) {
+		packet->header[0] =
+			HEADER_DATA_LENGTH(length) |
+			destination_id |
+			HEADER_TCODE(TCODE_STREAM_DATA);
+		packet->header_length = 4;
+		packet->payload = payload;
+		packet->payload_length = length;
+
+		goto common;
+	}
+
+	if (tcode > 0x10) {
+		ext_tcode = tcode & ~0x10;
+		tcode = TCODE_LOCK_REQUEST;
+	} else
+		ext_tcode = 0;
+
+	packet->header[0] =
+		HEADER_RETRY(RETRY_X) |
+		HEADER_TLABEL(tlabel) |
+		HEADER_TCODE(tcode) |
+		HEADER_DESTINATION(destination_id);
+	packet->header[1] =
+		HEADER_OFFSET_HIGH(offset >> 32) | HEADER_SOURCE(source_id);
+	packet->header[2] =
+		offset;
+
+	switch (tcode) {
+	case TCODE_WRITE_QUADLET_REQUEST:
+		packet->header[3] = *(u32 *)payload;
+		packet->header_length = 16;
+		packet->payload_length = 0;
+		break;
+
+	case TCODE_LOCK_REQUEST:
+	case TCODE_WRITE_BLOCK_REQUEST:
+		packet->header[3] =
+			HEADER_DATA_LENGTH(length) |
+			HEADER_EXTENDED_TCODE(ext_tcode);
+		packet->header_length = 16;
+		packet->payload = payload;
+		packet->payload_length = length;
+		break;
+
+	case TCODE_READ_QUADLET_REQUEST:
+		packet->header_length = 12;
+		packet->payload_length = 0;
+		break;
+
+	case TCODE_READ_BLOCK_REQUEST:
+		packet->header[3] =
+			HEADER_DATA_LENGTH(length) |
+			HEADER_EXTENDED_TCODE(ext_tcode);
+		packet->header_length = 16;
+		packet->payload_length = 0;
+		break;
+
+	default:
+		WARN(1, "wrong tcode %d\n", tcode);
+	}
+ common:
+	packet->speed = speed;
+	packet->generation = generation;
+	packet->ack = 0;
+	packet->payload_mapped = false;
+}
+
+static int allocate_tlabel(struct fw_card *card)
+{
+	int tlabel;
+
+	tlabel = card->current_tlabel;
+	while (card->tlabel_mask & (1ULL << tlabel)) {
+		tlabel = (tlabel + 1) & 0x3f;
+		if (tlabel == card->current_tlabel)
+			return -EBUSY;
+	}
+
+	card->current_tlabel = (tlabel + 1) & 0x3f;
+	card->tlabel_mask |= 1ULL << tlabel;
+
+	return tlabel;
+}
+
+/**
+ * fw_send_request() - submit a request packet for transmission
+ * @card:		interface to send the request at
+ * @t:			transaction instance to which the request belongs
+ * @tcode:		transaction code
+ * @destination_id:	destination node ID, consisting of bus_ID and phy_ID
+ * @generation:		bus generation in which request and response are valid
+ * @speed:		transmission speed
+ * @offset:		48bit wide offset into destination's address space
+ * @payload:		data payload for the request subaction
+ * @length:		length of the payload, in bytes
+ * @callback:		function to be called when the transaction is completed
+ * @callback_data:	data to be passed to the transaction completion callback
+ *
+ * Submit a request packet into the asynchronous request transmission queue.
+ * Can be called from atomic context.  If you prefer a blocking API, use
+ * fw_run_transaction() in a context that can sleep.
+ *
+ * In case of lock requests, specify one of the firewire-core specific %TCODE_
+ * constants instead of %TCODE_LOCK_REQUEST in @tcode.
+ *
+ * Make sure that the value in @destination_id is not older than the one in
+ * @generation.  Otherwise the request is in danger to be sent to a wrong node.
+ *
+ * In case of asynchronous stream packets i.e. %TCODE_STREAM_DATA, the caller
+ * needs to synthesize @destination_id with fw_stream_packet_destination_id().
+ * It will contain tag, channel, and sy data instead of a node ID then.
+ *
+ * The payload buffer at @data is going to be DMA-mapped except in case of
+ * @length <= 8 or of local (loopback) requests.  Hence make sure that the
+ * buffer complies with the restrictions of the streaming DMA mapping API.
+ * @payload must not be freed before the @callback is called.
+ *
+ * In case of request types without payload, @data is NULL and @length is 0.
+ *
+ * After the transaction is completed successfully or unsuccessfully, the
+ * @callback will be called.  Among its parameters is the response code which
+ * is either one of the rcodes per IEEE 1394 or, in case of internal errors,
+ * the firewire-core specific %RCODE_SEND_ERROR.  The other firewire-core
+ * specific rcodes (%RCODE_CANCELLED, %RCODE_BUSY, %RCODE_GENERATION,
+ * %RCODE_NO_ACK) denote transaction timeout, busy responder, stale request
+ * generation, or missing ACK respectively.
+ *
+ * Note some timing corner cases:  fw_send_request() may complete much earlier
+ * than when the request packet actually hits the wire.  On the other hand,
+ * transaction completion and hence execution of @callback may happen even
+ * before fw_send_request() returns.
+ */
+void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode,
+		     int destination_id, int generation, int speed,
+		     unsigned long long offset, void *payload, size_t length,
+		     fw_transaction_callback_t callback, void *callback_data)
+{
+	unsigned long flags;
+	int tlabel;
+
+	/*
+	 * Allocate tlabel from the bitmap and put the transaction on
+	 * the list while holding the card spinlock.
+	 */
+
+	spin_lock_irqsave(&card->lock, flags);
+
+	tlabel = allocate_tlabel(card);
+	if (tlabel < 0) {
+		spin_unlock_irqrestore(&card->lock, flags);
+		callback(card, RCODE_SEND_ERROR, NULL, 0, callback_data);
+		return;
+	}
+
+	t->node_id = destination_id;
+	t->tlabel = tlabel;
+	t->card = card;
+	t->is_split_transaction = false;
+	timer_setup(&t->split_timeout_timer,
+		    split_transaction_timeout_callback, 0);
+	t->callback = callback;
+	t->callback_data = callback_data;
+
+	fw_fill_request(&t->packet, tcode, t->tlabel,
+			destination_id, card->node_id, generation,
+			speed, offset, payload, length);
+	t->packet.callback = transmit_complete_callback;
+
+	list_add_tail(&t->link, &card->transaction_list);
+
+	spin_unlock_irqrestore(&card->lock, flags);
+
+	card->driver->send_request(card, &t->packet);
+}
+EXPORT_SYMBOL(fw_send_request);
+
+struct transaction_callback_data {
+	struct completion done;
+	void *payload;
+	int rcode;
+};
+
+static void transaction_callback(struct fw_card *card, int rcode,
+				 void *payload, size_t length, void *data)
+{
+	struct transaction_callback_data *d = data;
+
+	if (rcode == RCODE_COMPLETE)
+		memcpy(d->payload, payload, length);
+	d->rcode = rcode;
+	complete(&d->done);
+}
+
+/**
+ * fw_run_transaction() - send request and sleep until transaction is completed
+ *
+ * Returns the RCODE.  See fw_send_request() for parameter documentation.
+ * Unlike fw_send_request(), @data points to the payload of the request or/and
+ * to the payload of the response.  DMA mapping restrictions apply to outbound
+ * request payloads of >= 8 bytes but not to inbound response payloads.
+ */
+int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
+		       int generation, int speed, unsigned long long offset,
+		       void *payload, size_t length)
+{
+	struct transaction_callback_data d;
+	struct fw_transaction t;
+
+	timer_setup_on_stack(&t.split_timeout_timer, NULL, 0);
+	init_completion(&d.done);
+	d.payload = payload;
+	fw_send_request(card, &t, tcode, destination_id, generation, speed,
+			offset, payload, length, transaction_callback, &d);
+	wait_for_completion(&d.done);
+	destroy_timer_on_stack(&t.split_timeout_timer);
+
+	return d.rcode;
+}
+EXPORT_SYMBOL(fw_run_transaction);
+
+static DEFINE_MUTEX(phy_config_mutex);
+static DECLARE_COMPLETION(phy_config_done);
+
+static void transmit_phy_packet_callback(struct fw_packet *packet,
+					 struct fw_card *card, int status)
+{
+	complete(&phy_config_done);
+}
+
+static struct fw_packet phy_config_packet = {
+	.header_length	= 12,
+	.header[0]	= TCODE_LINK_INTERNAL << 4,
+	.payload_length	= 0,
+	.speed		= SCODE_100,
+	.callback	= transmit_phy_packet_callback,
+};
+
+void fw_send_phy_config(struct fw_card *card,
+			int node_id, int generation, int gap_count)
+{
+	long timeout = DIV_ROUND_UP(HZ, 10);
+	u32 data = PHY_IDENTIFIER(PHY_PACKET_CONFIG);
+
+	if (node_id != FW_PHY_CONFIG_NO_NODE_ID)
+		data |= PHY_CONFIG_ROOT_ID(node_id);
+
+	if (gap_count == FW_PHY_CONFIG_CURRENT_GAP_COUNT) {
+		gap_count = card->driver->read_phy_reg(card, 1);
+		if (gap_count < 0)
+			return;
+
+		gap_count &= 63;
+		if (gap_count == 63)
+			return;
+	}
+	data |= PHY_CONFIG_GAP_COUNT(gap_count);
+
+	mutex_lock(&phy_config_mutex);
+
+	phy_config_packet.header[1] = data;
+	phy_config_packet.header[2] = ~data;
+	phy_config_packet.generation = generation;
+	reinit_completion(&phy_config_done);
+
+	card->driver->send_request(card, &phy_config_packet);
+	wait_for_completion_timeout(&phy_config_done, timeout);
+
+	mutex_unlock(&phy_config_mutex);
+}
+
+static struct fw_address_handler *lookup_overlapping_address_handler(
+	struct list_head *list, unsigned long long offset, size_t length)
+{
+	struct fw_address_handler *handler;
+
+	list_for_each_entry_rcu(handler, list, link) {
+		if (handler->offset < offset + length &&
+		    offset < handler->offset + handler->length)
+			return handler;
+	}
+
+	return NULL;
+}
+
+static bool is_enclosing_handler(struct fw_address_handler *handler,
+				 unsigned long long offset, size_t length)
+{
+	return handler->offset <= offset &&
+		offset + length <= handler->offset + handler->length;
+}
+
+static struct fw_address_handler *lookup_enclosing_address_handler(
+	struct list_head *list, unsigned long long offset, size_t length)
+{
+	struct fw_address_handler *handler;
+
+	list_for_each_entry_rcu(handler, list, link) {
+		if (is_enclosing_handler(handler, offset, length))
+			return handler;
+	}
+
+	return NULL;
+}
+
+static DEFINE_SPINLOCK(address_handler_list_lock);
+static LIST_HEAD(address_handler_list);
+
+const struct fw_address_region fw_high_memory_region =
+	{ .start = FW_MAX_PHYSICAL_RANGE, .end = 0xffffe0000000ULL, };
+EXPORT_SYMBOL(fw_high_memory_region);
+
+static const struct fw_address_region low_memory_region =
+	{ .start = 0x000000000000ULL, .end = FW_MAX_PHYSICAL_RANGE, };
+
+#if 0
+const struct fw_address_region fw_private_region =
+	{ .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };
+const struct fw_address_region fw_csr_region =
+	{ .start = CSR_REGISTER_BASE,
+	  .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM_END,  };
+const struct fw_address_region fw_unit_space_region =
+	{ .start = 0xfffff0000900ULL, .end = 0x1000000000000ULL, };
+#endif  /*  0  */
+
+static bool is_in_fcp_region(u64 offset, size_t length)
+{
+	return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
+		offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
+}
+
+/**
+ * fw_core_add_address_handler() - register for incoming requests
+ * @handler:	callback
+ * @region:	region in the IEEE 1212 node space address range
+ *
+ * region->start, ->end, and handler->length have to be quadlet-aligned.
+ *
+ * When a request is received that falls within the specified address range,
+ * the specified callback is invoked.  The parameters passed to the callback
+ * give the details of the particular request.
+ *
+ * To be called in process context.
+ * Return value:  0 on success, non-zero otherwise.
+ *
+ * The start offset of the handler's address region is determined by
+ * fw_core_add_address_handler() and is returned in handler->offset.
+ *
+ * Address allocations are exclusive, except for the FCP registers.
+ */
+int fw_core_add_address_handler(struct fw_address_handler *handler,
+				const struct fw_address_region *region)
+{
+	struct fw_address_handler *other;
+	int ret = -EBUSY;
+
+	if (region->start & 0xffff000000000003ULL ||
+	    region->start >= region->end ||
+	    region->end   > 0x0001000000000000ULL ||
+	    handler->length & 3 ||
+	    handler->length == 0)
+		return -EINVAL;
+
+	spin_lock(&address_handler_list_lock);
+
+	handler->offset = region->start;
+	while (handler->offset + handler->length <= region->end) {
+		if (is_in_fcp_region(handler->offset, handler->length))
+			other = NULL;
+		else
+			other = lookup_overlapping_address_handler
+					(&address_handler_list,
+					 handler->offset, handler->length);
+		if (other != NULL) {
+			handler->offset += other->length;
+		} else {
+			list_add_tail_rcu(&handler->link, &address_handler_list);
+			ret = 0;
+			break;
+		}
+	}
+
+	spin_unlock(&address_handler_list_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL(fw_core_add_address_handler);
+
+/**
+ * fw_core_remove_address_handler() - unregister an address handler
+ *
+ * To be called in process context.
+ *
+ * When fw_core_remove_address_handler() returns, @handler->callback() is
+ * guaranteed to not run on any CPU anymore.
+ */
+void fw_core_remove_address_handler(struct fw_address_handler *handler)
+{
+	spin_lock(&address_handler_list_lock);
+	list_del_rcu(&handler->link);
+	spin_unlock(&address_handler_list_lock);
+	synchronize_rcu();
+}
+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);
+}
+
+int fw_get_response_length(struct fw_request *r)
+{
+	int tcode, ext_tcode, data_length;
+
+	tcode = HEADER_GET_TCODE(r->request_header[0]);
+
+	switch (tcode) {
+	case TCODE_WRITE_QUADLET_REQUEST:
+	case TCODE_WRITE_BLOCK_REQUEST:
+		return 0;
+
+	case TCODE_READ_QUADLET_REQUEST:
+		return 4;
+
+	case TCODE_READ_BLOCK_REQUEST:
+		data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
+		return data_length;
+
+	case TCODE_LOCK_REQUEST:
+		ext_tcode = HEADER_GET_EXTENDED_TCODE(r->request_header[3]);
+		data_length = HEADER_GET_DATA_LENGTH(r->request_header[3]);
+		switch (ext_tcode) {
+		case EXTCODE_FETCH_ADD:
+		case EXTCODE_LITTLE_ADD:
+			return data_length;
+		default:
+			return data_length / 2;
+		}
+
+	default:
+		WARN(1, "wrong tcode %d\n", tcode);
+		return 0;
+	}
+}
+
+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:
+		WARN(1, "wrong tcode %d\n", tcode);
+	}
+
+	response->payload_mapped = false;
+}
+EXPORT_SYMBOL(fw_fill_response);
+
+static u32 compute_split_timeout_timestamp(struct fw_card *card,
+					   u32 request_timestamp)
+{
+	unsigned int cycles;
+	u32 timestamp;
+
+	cycles = card->split_timeout_cycles;
+	cycles += request_timestamp & 0x1fff;
+
+	timestamp = request_timestamp & ~0x1fff;
+	timestamp += (cycles / 8000) << 13;
+	timestamp |= cycles % 8000;
+
+	return timestamp;
+}
+
+static struct fw_request *allocate_request(struct fw_card *card,
+					   struct fw_packet *p)
+{
+	struct fw_request *request;
+	u32 *data, length;
+	int request_tcode;
+
+	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:
+		fw_notice(card, "ERROR - corrupt request received - %08x %08x %08x\n",
+			 p->header[0], p->header[1], p->header[2]);
+		return NULL;
+	}
+
+	request = kmalloc(sizeof(*request) + length, GFP_ATOMIC);
+	if (request == NULL)
+		return NULL;
+
+	request->response.speed = p->speed;
+	request->response.timestamp =
+			compute_split_timeout_timestamp(card, p->timestamp);
+	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)
+{
+	if (WARN_ONCE(!request, "invalid for FCP address handlers"))
+		return;
+
+	/* unified transaction or broadcast transaction: don't respond */
+	if (request->ack != ACK_PENDING ||
+	    HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) {
+		kfree(request);
+		return;
+	}
+
+	if (rcode == RCODE_COMPLETE)
+		fw_fill_response(&request->response, request->request_header,
+				 rcode, request->data,
+				 fw_get_response_length(request));
+	else
+		fw_fill_response(&request->response, request->request_header,
+				 rcode, NULL, 0);
+
+	card->driver->send_response(card, &request->response);
+}
+EXPORT_SYMBOL(fw_send_response);
+
+/**
+ * fw_get_request_speed() - returns speed at which the @request was received
+ */
+int fw_get_request_speed(struct fw_request *request)
+{
+	return request->response.speed;
+}
+EXPORT_SYMBOL(fw_get_request_speed);
+
+static void handle_exclusive_region_request(struct fw_card *card,
+					    struct fw_packet *p,
+					    struct fw_request *request,
+					    unsigned long long offset)
+{
+	struct fw_address_handler *handler;
+	int tcode, destination, source;
+
+	destination = HEADER_GET_DESTINATION(p->header[0]);
+	source      = HEADER_GET_SOURCE(p->header[1]);
+	tcode       = HEADER_GET_TCODE(p->header[0]);
+	if (tcode == TCODE_LOCK_REQUEST)
+		tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
+
+	rcu_read_lock();
+	handler = lookup_enclosing_address_handler(&address_handler_list,
+						   offset, request->length);
+	if (handler)
+		handler->address_callback(card, request,
+					  tcode, destination, source,
+					  p->generation, offset,
+					  request->data, request->length,
+					  handler->callback_data);
+	rcu_read_unlock();
+
+	if (!handler)
+		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
+}
+
+static void handle_fcp_region_request(struct fw_card *card,
+				      struct fw_packet *p,
+				      struct fw_request *request,
+				      unsigned long long offset)
+{
+	struct fw_address_handler *handler;
+	int tcode, destination, source;
+
+	if ((offset != (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
+	     offset != (CSR_REGISTER_BASE | CSR_FCP_RESPONSE)) ||
+	    request->length > 0x200) {
+		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
+
+		return;
+	}
+
+	tcode       = HEADER_GET_TCODE(p->header[0]);
+	destination = HEADER_GET_DESTINATION(p->header[0]);
+	source      = HEADER_GET_SOURCE(p->header[1]);
+
+	if (tcode != TCODE_WRITE_QUADLET_REQUEST &&
+	    tcode != TCODE_WRITE_BLOCK_REQUEST) {
+		fw_send_response(card, request, RCODE_TYPE_ERROR);
+
+		return;
+	}
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(handler, &address_handler_list, link) {
+		if (is_enclosing_handler(handler, offset, request->length))
+			handler->address_callback(card, NULL, tcode,
+						  destination, source,
+						  p->generation, offset,
+						  request->data,
+						  request->length,
+						  handler->callback_data);
+	}
+	rcu_read_unlock();
+
+	fw_send_response(card, request, RCODE_COMPLETE);
+}
+
+void fw_core_handle_request(struct fw_card *card, struct fw_packet *p)
+{
+	struct fw_request *request;
+	unsigned long long offset;
+
+	if (p->ack != ACK_PENDING && p->ack != ACK_COMPLETE)
+		return;
+
+	if (TCODE_IS_LINK_INTERNAL(HEADER_GET_TCODE(p->header[0]))) {
+		fw_cdev_handle_phy_packet(card, p);
+		return;
+	}
+
+	request = allocate_request(card, p);
+	if (request == NULL) {
+		/* FIXME: send statically allocated busy packet. */
+		return;
+	}
+
+	offset = ((u64)HEADER_GET_OFFSET_HIGH(p->header[1]) << 32) |
+		p->header[2];
+
+	if (!is_in_fcp_region(offset, request->length))
+		handle_exclusive_region_request(card, p, request, offset);
+	else
+		handle_fcp_region_request(card, p, request, offset);
+
+}
+EXPORT_SYMBOL(fw_core_handle_request);
+
+void fw_core_handle_response(struct fw_card *card, struct fw_packet *p)
+{
+	struct fw_transaction *t = NULL, *iter;
+	unsigned long flags;
+	u32 *data;
+	size_t data_length;
+	int tcode, tlabel, source, rcode;
+
+	tcode	= HEADER_GET_TCODE(p->header[0]);
+	tlabel	= HEADER_GET_TLABEL(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(iter, &card->transaction_list, link) {
+		if (iter->node_id == source && iter->tlabel == tlabel) {
+			if (!try_cancel_split_timeout(iter)) {
+				spin_unlock_irqrestore(&card->lock, flags);
+				goto timed_out;
+			}
+			list_del_init(&iter->link);
+			card->tlabel_mask &= ~(1ULL << iter->tlabel);
+			t = iter;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&card->lock, flags);
+
+	if (!t) {
+ timed_out:
+		fw_notice(card, "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;
+	}
+
+	/*
+	 * The response handler may be executed while the request handler
+	 * is still pending.  Cancel the request handler.
+	 */
+	card->driver->cancel_packet(card, &t->packet);
+
+	t->callback(card, rcode, data, data_length, t->callback_data);
+}
+EXPORT_SYMBOL(fw_core_handle_response);
+
+/**
+ * fw_rcode_string - convert a firewire result code to an error description
+ * @rcode: the result code
+ */
+const char *fw_rcode_string(int rcode)
+{
+	static const char *const names[] = {
+		[RCODE_COMPLETE]       = "no error",
+		[RCODE_CONFLICT_ERROR] = "conflict error",
+		[RCODE_DATA_ERROR]     = "data error",
+		[RCODE_TYPE_ERROR]     = "type error",
+		[RCODE_ADDRESS_ERROR]  = "address error",
+		[RCODE_SEND_ERROR]     = "send error",
+		[RCODE_CANCELLED]      = "timeout",
+		[RCODE_BUSY]           = "busy",
+		[RCODE_GENERATION]     = "bus reset",
+		[RCODE_NO_ACK]         = "no ack",
+	};
+
+	if ((unsigned int)rcode < ARRAY_SIZE(names) && names[rcode])
+		return names[rcode];
+	else
+		return "unknown";
+}
+EXPORT_SYMBOL(fw_rcode_string);
+
+static const struct fw_address_region topology_map_region =
+	{ .start = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP,
+	  .end   = CSR_REGISTER_BASE | CSR_TOPOLOGY_MAP_END, };
+
+static void handle_topology_map(struct fw_card *card, struct fw_request *request,
+		int tcode, int destination, int source, int generation,
+		unsigned long long offset, void *payload, size_t length,
+		void *callback_data)
+{
+	int start;
+
+	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;
+	memcpy(payload, &card->topology_map[start], length);
+
+	fw_send_response(card, request, RCODE_COMPLETE);
+}
+
+static struct fw_address_handler topology_map = {
+	.length			= 0x400,
+	.address_callback	= handle_topology_map,
+};
+
+static const struct fw_address_region registers_region =
+	{ .start = CSR_REGISTER_BASE,
+	  .end   = CSR_REGISTER_BASE | CSR_CONFIG_ROM, };
+
+static void update_split_timeout(struct fw_card *card)
+{
+	unsigned int cycles;
+
+	cycles = card->split_timeout_hi * 8000 + (card->split_timeout_lo >> 19);
+
+	/* minimum per IEEE 1394, maximum which doesn't overflow OHCI */
+	cycles = clamp(cycles, 800u, 3u * 8000u);
+
+	card->split_timeout_cycles = cycles;
+	card->split_timeout_jiffies = DIV_ROUND_UP(cycles * HZ, 8000);
+}
+
+static void handle_registers(struct fw_card *card, struct fw_request *request,
+		int tcode, int destination, int source, int generation,
+		unsigned long long offset, void *payload, size_t length,
+		void *callback_data)
+{
+	int reg = offset & ~CSR_REGISTER_BASE;
+	__be32 *data = payload;
+	int rcode = RCODE_COMPLETE;
+	unsigned long flags;
+
+	switch (reg) {
+	case CSR_PRIORITY_BUDGET:
+		if (!card->priority_budget_implemented) {
+			rcode = RCODE_ADDRESS_ERROR;
+			break;
+		}
+		/* else fall through */
+
+	case CSR_NODE_IDS:
+		/*
+		 * per IEEE 1394-2008 8.3.22.3, not IEEE 1394.1-2004 3.2.8
+		 * and 9.6, but interoperable with IEEE 1394.1-2004 bridges
+		 */
+		/* fall through */
+
+	case CSR_STATE_CLEAR:
+	case CSR_STATE_SET:
+	case CSR_CYCLE_TIME:
+	case CSR_BUS_TIME:
+	case CSR_BUSY_TIMEOUT:
+		if (tcode == TCODE_READ_QUADLET_REQUEST)
+			*data = cpu_to_be32(card->driver->read_csr(card, reg));
+		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
+			card->driver->write_csr(card, reg, be32_to_cpu(*data));
+		else
+			rcode = RCODE_TYPE_ERROR;
+		break;
+
+	case CSR_RESET_START:
+		if (tcode == TCODE_WRITE_QUADLET_REQUEST)
+			card->driver->write_csr(card, CSR_STATE_CLEAR,
+						CSR_STATE_BIT_ABDICATE);
+		else
+			rcode = RCODE_TYPE_ERROR;
+		break;
+
+	case CSR_SPLIT_TIMEOUT_HI:
+		if (tcode == TCODE_READ_QUADLET_REQUEST) {
+			*data = cpu_to_be32(card->split_timeout_hi);
+		} else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
+			spin_lock_irqsave(&card->lock, flags);
+			card->split_timeout_hi = be32_to_cpu(*data) & 7;
+			update_split_timeout(card);
+			spin_unlock_irqrestore(&card->lock, flags);
+		} else {
+			rcode = RCODE_TYPE_ERROR;
+		}
+		break;
+
+	case CSR_SPLIT_TIMEOUT_LO:
+		if (tcode == TCODE_READ_QUADLET_REQUEST) {
+			*data = cpu_to_be32(card->split_timeout_lo);
+		} else if (tcode == TCODE_WRITE_QUADLET_REQUEST) {
+			spin_lock_irqsave(&card->lock, flags);
+			card->split_timeout_lo =
+					be32_to_cpu(*data) & 0xfff80000;
+			update_split_timeout(card);
+			spin_unlock_irqrestore(&card->lock, flags);
+		} else {
+			rcode = RCODE_TYPE_ERROR;
+		}
+		break;
+
+	case CSR_MAINT_UTILITY:
+		if (tcode == TCODE_READ_QUADLET_REQUEST)
+			*data = card->maint_utility_register;
+		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
+			card->maint_utility_register = *data;
+		else
+			rcode = RCODE_TYPE_ERROR;
+		break;
+
+	case CSR_BROADCAST_CHANNEL:
+		if (tcode == TCODE_READ_QUADLET_REQUEST)
+			*data = cpu_to_be32(card->broadcast_channel);
+		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)
+			card->broadcast_channel =
+			    (be32_to_cpu(*data) & BROADCAST_CHANNEL_VALID) |
+			    BROADCAST_CHANNEL_INITIAL;
+		else
+			rcode = RCODE_TYPE_ERROR;
+		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;
+
+	default:
+		rcode = RCODE_ADDRESS_ERROR;
+		break;
+	}
+
+	fw_send_response(card, request, rcode);
+}
+
+static struct fw_address_handler registers = {
+	.length			= 0x400,
+	.address_callback	= handle_registers,
+};
+
+static void handle_low_memory(struct fw_card *card, struct fw_request *request,
+		int tcode, int destination, int source, int generation,
+		unsigned long long offset, void *payload, size_t length,
+		void *callback_data)
+{
+	/*
+	 * This catches requests not handled by the physical DMA unit,
+	 * i.e., wrong transaction types or unauthorized source nodes.
+	 */
+	fw_send_response(card, request, RCODE_TYPE_ERROR);
+}
+
+static struct fw_address_handler low_memory = {
+	.length			= FW_MAX_PHYSICAL_RANGE,
+	.address_callback	= handle_low_memory,
+};
+
+MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
+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 = 0x03001f11,
+	.key = 0x81000000,
+	.data = vendor_textual_descriptor,
+};
+
+static struct fw_descriptor model_id_descriptor = {
+	.length = ARRAY_SIZE(model_textual_descriptor),
+	.immediate = 0x17023901,
+	.key = 0x81000000,
+	.data = model_textual_descriptor,
+};
+
+static int __init fw_core_init(void)
+{
+	int ret;
+
+	fw_workqueue = alloc_workqueue("firewire", WQ_MEM_RECLAIM, 0);
+	if (!fw_workqueue)
+		return -ENOMEM;
+
+	ret = bus_register(&fw_bus_type);
+	if (ret < 0) {
+		destroy_workqueue(fw_workqueue);
+		return ret;
+	}
+
+	fw_cdev_major = register_chrdev(0, "firewire", &fw_device_ops);
+	if (fw_cdev_major < 0) {
+		bus_unregister(&fw_bus_type);
+		destroy_workqueue(fw_workqueue);
+		return fw_cdev_major;
+	}
+
+	fw_core_add_address_handler(&topology_map, &topology_map_region);
+	fw_core_add_address_handler(&registers, &registers_region);
+	fw_core_add_address_handler(&low_memory, &low_memory_region);
+	fw_core_add_descriptor(&vendor_id_descriptor);
+	fw_core_add_descriptor(&model_id_descriptor);
+
+	return 0;
+}
+
+static void __exit fw_core_cleanup(void)
+{
+	unregister_chrdev(fw_cdev_major, "firewire");
+	bus_unregister(&fw_bus_type);
+	destroy_workqueue(fw_workqueue);
+	idr_destroy(&fw_device_idr);
+}
+
+module_init(fw_core_init);
+module_exit(fw_core_cleanup);