2 * Copyright (C) 2005-2007 Kristian Hoegsberg <krh@bitplanet.net>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software Foundation,
16 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 #include <linux/bug.h>
20 #include <linux/completion.h>
21 #include <linux/crc-itu-t.h>
22 #include <linux/device.h>
23 #include <linux/errno.h>
24 #include <linux/firewire.h>
25 #include <linux/firewire-constants.h>
26 #include <linux/jiffies.h>
27 #include <linux/kernel.h>
28 #include <linux/kref.h>
29 #include <linux/list.h>
30 #include <linux/module.h>
31 #include <linux/mutex.h>
32 #include <linux/spinlock.h>
33 #include <linux/workqueue.h>
35 #include <asm/atomic.h>
36 #include <asm/byteorder.h>
40 int fw_compute_block_crc(__be32 *block)
45 length = (be32_to_cpu(block[0]) >> 16) & 0xff;
46 crc = crc_itu_t(0, (u8 *)&block[1], length * 4);
47 *block |= cpu_to_be32(crc);
52 static DEFINE_MUTEX(card_mutex);
53 static LIST_HEAD(card_list);
55 static LIST_HEAD(descriptor_list);
56 static int descriptor_count;
58 static __be32 tmp_config_rom[256];
59 /* ROM header, bus info block, root dir header, capabilities = 7 quadlets */
60 static size_t config_rom_length = 1 + 4 + 1 + 1;
62 #define BIB_CRC(v) ((v) << 0)
63 #define BIB_CRC_LENGTH(v) ((v) << 16)
64 #define BIB_INFO_LENGTH(v) ((v) << 24)
65 #define BIB_BUS_NAME 0x31333934 /* "1394" */
66 #define BIB_LINK_SPEED(v) ((v) << 0)
67 #define BIB_GENERATION(v) ((v) << 4)
68 #define BIB_MAX_ROM(v) ((v) << 8)
69 #define BIB_MAX_RECEIVE(v) ((v) << 12)
70 #define BIB_CYC_CLK_ACC(v) ((v) << 16)
71 #define BIB_PMC ((1) << 27)
72 #define BIB_BMC ((1) << 28)
73 #define BIB_ISC ((1) << 29)
74 #define BIB_CMC ((1) << 30)
75 #define BIB_IRMC ((1) << 31)
76 #define NODE_CAPABILITIES 0x0c0083c0 /* per IEEE 1394 clause 8.3.2.6.5.2 */
78 static void generate_config_rom(struct fw_card *card, __be32 *config_rom)
80 struct fw_descriptor *desc;
84 * Initialize contents of config rom buffer. On the OHCI
85 * controller, block reads to the config rom accesses the host
86 * memory, but quadlet read access the hardware bus info block
87 * registers. That's just crack, but it means we should make
88 * sure the contents of bus info block in host memory matches
89 * the version stored in the OHCI registers.
92 config_rom[0] = cpu_to_be32(
93 BIB_CRC_LENGTH(4) | BIB_INFO_LENGTH(4) | BIB_CRC(0));
94 config_rom[1] = cpu_to_be32(BIB_BUS_NAME);
95 config_rom[2] = cpu_to_be32(
96 BIB_LINK_SPEED(card->link_speed) |
97 BIB_GENERATION(card->config_rom_generation++ % 14 + 2) |
99 BIB_MAX_RECEIVE(card->max_receive) |
100 BIB_BMC | BIB_ISC | BIB_CMC | BIB_IRMC);
101 config_rom[3] = cpu_to_be32(card->guid >> 32);
102 config_rom[4] = cpu_to_be32(card->guid);
104 /* Generate root directory. */
105 config_rom[6] = cpu_to_be32(NODE_CAPABILITIES);
107 j = 7 + descriptor_count;
109 /* Generate root directory entries for descriptors. */
110 list_for_each_entry (desc, &descriptor_list, link) {
111 if (desc->immediate > 0)
112 config_rom[i++] = cpu_to_be32(desc->immediate);
113 config_rom[i] = cpu_to_be32(desc->key | (j - i));
118 /* Update root directory length. */
119 config_rom[5] = cpu_to_be32((i - 5 - 1) << 16);
121 /* End of root directory, now copy in descriptors. */
122 list_for_each_entry (desc, &descriptor_list, link) {
123 for (k = 0; k < desc->length; k++)
124 config_rom[i + k] = cpu_to_be32(desc->data[k]);
128 /* Calculate CRCs for all blocks in the config rom. This
129 * assumes that CRC length and info length are identical for
130 * the bus info block, which is always the case for this
132 for (i = 0; i < j; i += length + 1)
133 length = fw_compute_block_crc(config_rom + i);
135 WARN_ON(j != config_rom_length);
138 static void update_config_roms(void)
140 struct fw_card *card;
142 list_for_each_entry (card, &card_list, link) {
143 generate_config_rom(card, tmp_config_rom);
144 card->driver->set_config_rom(card, tmp_config_rom,
149 static size_t required_space(struct fw_descriptor *desc)
151 /* descriptor + entry into root dir + optional immediate entry */
152 return desc->length + 1 + (desc->immediate > 0 ? 1 : 0);
155 int fw_core_add_descriptor(struct fw_descriptor *desc)
161 * Check descriptor is valid; the length of all blocks in the
162 * descriptor has to add up to exactly the length of the
166 while (i < desc->length)
167 i += (desc->data[i] >> 16) + 1;
169 if (i != desc->length)
172 mutex_lock(&card_mutex);
174 if (config_rom_length + required_space(desc) > 256) {
177 list_add_tail(&desc->link, &descriptor_list);
178 config_rom_length += required_space(desc);
180 if (desc->immediate > 0)
182 update_config_roms();
186 mutex_unlock(&card_mutex);
190 EXPORT_SYMBOL(fw_core_add_descriptor);
192 void fw_core_remove_descriptor(struct fw_descriptor *desc)
194 mutex_lock(&card_mutex);
196 list_del(&desc->link);
197 config_rom_length -= required_space(desc);
199 if (desc->immediate > 0)
201 update_config_roms();
203 mutex_unlock(&card_mutex);
205 EXPORT_SYMBOL(fw_core_remove_descriptor);
207 static void allocate_broadcast_channel(struct fw_card *card, int generation)
209 int channel, bandwidth = 0;
211 if (!card->broadcast_channel_allocated) {
212 fw_iso_resource_manage(card, generation, 1ULL << 31,
213 &channel, &bandwidth, true,
214 card->bm_transaction_data);
216 fw_notify("failed to allocate broadcast channel\n");
219 card->broadcast_channel_allocated = true;
222 device_for_each_child(card->device, (void *)(long)generation,
223 fw_device_set_broadcast_channel);
226 static const char gap_count_table[] = {
227 63, 5, 7, 8, 10, 13, 16, 18, 21, 24, 26, 29, 32, 35, 37, 40
230 void fw_schedule_bm_work(struct fw_card *card, unsigned long delay)
233 if (!schedule_delayed_work(&card->work, delay))
237 static void fw_card_bm_work(struct work_struct *work)
239 struct fw_card *card = container_of(work, struct fw_card, work.work);
240 struct fw_device *root_device;
241 struct fw_node *root_node;
243 int root_id, new_root_id, irm_id, local_id;
244 int gap_count, generation, grace, rcode;
245 bool do_reset = false;
246 bool root_device_is_running;
247 bool root_device_is_cmc;
249 spin_lock_irqsave(&card->lock, flags);
251 if (card->local_node == NULL) {
252 spin_unlock_irqrestore(&card->lock, flags);
256 generation = card->generation;
257 root_node = card->root_node;
258 fw_node_get(root_node);
259 root_device = root_node->data;
260 root_device_is_running = root_device &&
261 atomic_read(&root_device->state) == FW_DEVICE_RUNNING;
262 root_device_is_cmc = root_device && root_device->cmc;
263 root_id = root_node->node_id;
264 irm_id = card->irm_node->node_id;
265 local_id = card->local_node->node_id;
267 grace = time_after(jiffies, card->reset_jiffies + DIV_ROUND_UP(HZ, 8));
269 if ((is_next_generation(generation, card->bm_generation) &&
270 !card->bm_abdicate) ||
271 (card->bm_generation != generation && grace)) {
273 * This first step is to figure out who is IRM and
274 * then try to become bus manager. If the IRM is not
275 * well defined (e.g. does not have an active link
276 * layer or does not responds to our lock request, we
277 * will have to do a little vigilante bus management.
278 * In that case, we do a goto into the gap count logic
279 * so that when we do the reset, we still optimize the
280 * gap count. That could well save a reset in the
284 if (!card->irm_node->link_on) {
285 new_root_id = local_id;
286 fw_notify("IRM has link off, making local node (%02x) root.\n",
291 card->bm_transaction_data[0] = cpu_to_be32(0x3f);
292 card->bm_transaction_data[1] = cpu_to_be32(local_id);
294 spin_unlock_irqrestore(&card->lock, flags);
296 rcode = fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
297 irm_id, generation, SCODE_100,
298 CSR_REGISTER_BASE + CSR_BUS_MANAGER_ID,
299 card->bm_transaction_data, 8);
301 if (rcode == RCODE_GENERATION)
302 /* Another bus reset, BM work has been rescheduled. */
305 if (rcode == RCODE_COMPLETE &&
306 card->bm_transaction_data[0] != cpu_to_be32(0x3f)) {
308 /* Somebody else is BM. Only act as IRM. */
309 if (local_id == irm_id)
310 allocate_broadcast_channel(card, generation);
315 if (rcode == RCODE_SEND_ERROR) {
317 * We have been unable to send the lock request due to
318 * some local problem. Let's try again later and hope
319 * that the problem has gone away by then.
321 fw_schedule_bm_work(card, DIV_ROUND_UP(HZ, 8));
325 spin_lock_irqsave(&card->lock, flags);
327 if (rcode != RCODE_COMPLETE) {
329 * The lock request failed, maybe the IRM
330 * isn't really IRM capable after all. Let's
331 * do a bus reset and pick the local node as
332 * root, and thus, IRM.
334 new_root_id = local_id;
335 fw_notify("BM lock failed, making local node (%02x) root.\n",
339 } else if (card->bm_generation != generation) {
341 * We weren't BM in the last generation, and the last
342 * bus reset is less than 125ms ago. Reschedule this job.
344 spin_unlock_irqrestore(&card->lock, flags);
345 fw_schedule_bm_work(card, DIV_ROUND_UP(HZ, 8));
350 * We're bus manager for this generation, so next step is to
351 * make sure we have an active cycle master and do gap count
354 card->bm_generation = generation;
356 if (root_device == NULL) {
358 * Either link_on is false, or we failed to read the
359 * config rom. In either case, pick another root.
361 new_root_id = local_id;
362 } else if (!root_device_is_running) {
364 * If we haven't probed this device yet, bail out now
365 * and let's try again once that's done.
367 spin_unlock_irqrestore(&card->lock, flags);
369 } else if (root_device_is_cmc) {
371 * We will send out a force root packet for this
372 * node as part of the gap count optimization.
374 new_root_id = root_id;
377 * Current root has an active link layer and we
378 * successfully read the config rom, but it's not
379 * cycle master capable.
381 new_root_id = local_id;
386 * Pick a gap count from 1394a table E-1. The table doesn't cover
387 * the typically much larger 1394b beta repeater delays though.
389 if (!card->beta_repeaters_present &&
390 root_node->max_hops < ARRAY_SIZE(gap_count_table))
391 gap_count = gap_count_table[root_node->max_hops];
396 * Finally, figure out if we should do a reset or not. If we have
397 * done less than 5 resets with the same physical topology and we
398 * have either a new root or a new gap count setting, let's do it.
401 if (card->bm_retries++ < 5 &&
402 (card->gap_count != gap_count || new_root_id != root_id))
405 spin_unlock_irqrestore(&card->lock, flags);
408 fw_notify("phy config: card %d, new root=%x, gap_count=%d\n",
409 card->index, new_root_id, gap_count);
410 fw_send_phy_config(card, new_root_id, generation, gap_count);
411 fw_core_initiate_bus_reset(card, 1);
412 /* Will allocate broadcast channel after the reset. */
416 if (root_device_is_cmc) {
418 * Make sure that the cycle master sends cycle start packets.
420 card->bm_transaction_data[0] = cpu_to_be32(CSR_STATE_BIT_CMSTR);
421 rcode = fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
422 root_id, generation, SCODE_100,
423 CSR_REGISTER_BASE + CSR_STATE_SET,
424 card->bm_transaction_data, 4);
425 if (rcode == RCODE_GENERATION)
429 if (local_id == irm_id)
430 allocate_broadcast_channel(card, generation);
433 fw_node_put(root_node);
438 void fw_card_initialize(struct fw_card *card,
439 const struct fw_card_driver *driver,
440 struct device *device)
442 static atomic_t index = ATOMIC_INIT(-1);
444 card->index = atomic_inc_return(&index);
445 card->driver = driver;
446 card->device = device;
447 card->current_tlabel = 0;
448 card->tlabel_mask = 0;
449 card->split_timeout_hi = 0;
450 card->split_timeout_lo = 800 << 19;
451 card->split_timeout_cycles = 800;
452 card->split_timeout_jiffies = DIV_ROUND_UP(HZ, 10);
454 card->broadcast_channel = BROADCAST_CHANNEL_INITIAL;
456 kref_init(&card->kref);
457 init_completion(&card->done);
458 INIT_LIST_HEAD(&card->transaction_list);
459 spin_lock_init(&card->lock);
461 card->local_node = NULL;
463 INIT_DELAYED_WORK(&card->work, fw_card_bm_work);
465 EXPORT_SYMBOL(fw_card_initialize);
467 int fw_card_add(struct fw_card *card,
468 u32 max_receive, u32 link_speed, u64 guid)
472 card->max_receive = max_receive;
473 card->link_speed = link_speed;
476 mutex_lock(&card_mutex);
478 generate_config_rom(card, tmp_config_rom);
479 ret = card->driver->enable(card, tmp_config_rom, config_rom_length);
481 list_add_tail(&card->link, &card_list);
483 mutex_unlock(&card_mutex);
487 EXPORT_SYMBOL(fw_card_add);
491 * The next few functions implement a dummy driver that is used once a card
492 * driver shuts down an fw_card. This allows the driver to cleanly unload,
493 * as all IO to the card will be handled (and failed) by the dummy driver
494 * instead of calling into the module. Only functions for iso context
495 * shutdown still need to be provided by the card driver.
498 static int dummy_enable(struct fw_card *card,
499 const __be32 *config_rom, size_t length)
505 static int dummy_update_phy_reg(struct fw_card *card, int address,
506 int clear_bits, int set_bits)
511 static int dummy_set_config_rom(struct fw_card *card,
512 const __be32 *config_rom, size_t length)
515 * We take the card out of card_list before setting the dummy
516 * driver, so this should never get called.
522 static void dummy_send_request(struct fw_card *card, struct fw_packet *packet)
524 packet->callback(packet, card, -ENODEV);
527 static void dummy_send_response(struct fw_card *card, struct fw_packet *packet)
529 packet->callback(packet, card, -ENODEV);
532 static int dummy_cancel_packet(struct fw_card *card, struct fw_packet *packet)
537 static int dummy_enable_phys_dma(struct fw_card *card,
538 int node_id, int generation)
543 static const struct fw_card_driver dummy_driver_template = {
544 .enable = dummy_enable,
545 .update_phy_reg = dummy_update_phy_reg,
546 .set_config_rom = dummy_set_config_rom,
547 .send_request = dummy_send_request,
548 .cancel_packet = dummy_cancel_packet,
549 .send_response = dummy_send_response,
550 .enable_phys_dma = dummy_enable_phys_dma,
553 void fw_card_release(struct kref *kref)
555 struct fw_card *card = container_of(kref, struct fw_card, kref);
557 complete(&card->done);
560 void fw_core_remove_card(struct fw_card *card)
562 struct fw_card_driver dummy_driver = dummy_driver_template;
564 card->driver->update_phy_reg(card, 4,
565 PHY_LINK_ACTIVE | PHY_CONTENDER, 0);
566 fw_core_initiate_bus_reset(card, 1);
568 mutex_lock(&card_mutex);
569 list_del_init(&card->link);
570 mutex_unlock(&card_mutex);
572 /* Switch off most of the card driver interface. */
573 dummy_driver.free_iso_context = card->driver->free_iso_context;
574 dummy_driver.stop_iso = card->driver->stop_iso;
575 card->driver = &dummy_driver;
577 fw_destroy_nodes(card);
579 /* Wait for all users, especially device workqueue jobs, to finish. */
581 wait_for_completion(&card->done);
583 WARN_ON(!list_empty(&card->transaction_list));
585 EXPORT_SYMBOL(fw_core_remove_card);
587 int fw_core_initiate_bus_reset(struct fw_card *card, int short_reset)
589 int reg = short_reset ? 5 : 1;
590 int bit = short_reset ? PHY_BUS_SHORT_RESET : PHY_BUS_RESET;
592 return card->driver->update_phy_reg(card, reg, 0, bit);
594 EXPORT_SYMBOL(fw_core_initiate_bus_reset);