/* * Copyright (C) 2005-2007 Kristian Hoegsberg * * 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 #include #include #include #include #include "fw-transaction.h" #include "fw-topology.h" #include "fw-device.h" int fw_compute_block_crc(u32 *block) { __be32 be32_block[256]; int i, length; length = (*block >> 16) & 0xff; for (i = 0; i < length; i++) be32_block[i] = cpu_to_be32(block[i + 1]); *block |= crc_itu_t(0, (u8 *) be32_block, length * 4); return length; } static DEFINE_MUTEX(card_mutex); static LIST_HEAD(card_list); static LIST_HEAD(descriptor_list); static int descriptor_count; #define BIB_CRC(v) ((v) << 0) #define BIB_CRC_LENGTH(v) ((v) << 16) #define BIB_INFO_LENGTH(v) ((v) << 24) #define BIB_LINK_SPEED(v) ((v) << 0) #define BIB_GENERATION(v) ((v) << 4) #define BIB_MAX_ROM(v) ((v) << 8) #define BIB_MAX_RECEIVE(v) ((v) << 12) #define BIB_CYC_CLK_ACC(v) ((v) << 16) #define BIB_PMC ((1) << 27) #define BIB_BMC ((1) << 28) #define BIB_ISC ((1) << 29) #define BIB_CMC ((1) << 30) #define BIB_IMC ((1) << 31) static u32 * generate_config_rom(struct fw_card *card, size_t *config_rom_length) { struct fw_descriptor *desc; static u32 config_rom[256]; int i, j, length; /* * Initialize contents of config rom buffer. On the OHCI * controller, block reads to the config rom accesses the host * memory, but quadlet read access the hardware bus info block * registers. That's just crack, but it means we should make * sure the contents of bus info block in host memory mathces * the version stored in the OHCI registers. */ memset(config_rom, 0, sizeof(config_rom)); config_rom[0] = BIB_CRC_LENGTH(4) | BIB_INFO_LENGTH(4) | BIB_CRC(0); config_rom[1] = 0x31333934; config_rom[2] = BIB_LINK_SPEED(card->link_speed) | BIB_GENERATION(card->config_rom_generation++ % 14 + 2) | BIB_MAX_ROM(2) | BIB_MAX_RECEIVE(card->max_receive) | BIB_BMC | BIB_ISC | BIB_CMC | BIB_IMC; config_rom[3] = card->guid >> 32; config_rom[4] = card->guid; /* Generate root directory. */ i = 5; config_rom[i++] = 0; config_rom[i++] = 0x0c0083c0; /* node capabilities */ j = i + descriptor_count; /* Generate root directory entries for descriptors. */ list_for_each_entry (desc, &descriptor_list, link) { if (desc->immediate > 0) config_rom[i++] = desc->immediate; config_rom[i] = desc->key | (j - i); i++; j += desc->length; } /* Update root directory length. */ config_rom[5] = (i - 5 - 1) << 16; /* End of root directory, now copy in descriptors. */ list_for_each_entry (desc, &descriptor_list, link) { memcpy(&config_rom[i], desc->data, desc->length * 4); i += desc->length; } /* Calculate CRCs for all blocks in the config rom. This * assumes that CRC length and info length are identical for * the bus info block, which is always the case for this * implementation. */ for (i = 0; i < j; i += length + 1) length = fw_compute_block_crc(config_rom + i); *config_rom_length = j; return config_rom; } static void update_config_roms(void) { struct fw_card *card; u32 *config_rom; size_t length; list_for_each_entry (card, &card_list, link) { config_rom = generate_config_rom(card, &length); card->driver->set_config_rom(card, config_rom, length); } } int fw_core_add_descriptor(struct fw_descriptor *desc) { size_t i; /* * Check descriptor is valid; the length of all blocks in the * descriptor has to add up to exactly the length of the * block. */ i = 0; while (i < desc->length) i += (desc->data[i] >> 16) + 1; if (i != desc->length) return -EINVAL; mutex_lock(&card_mutex); list_add_tail(&desc->link, &descriptor_list); descriptor_count++; if (desc->immediate > 0) descriptor_count++; update_config_roms(); mutex_unlock(&card_mutex); return 0; } EXPORT_SYMBOL(fw_core_add_descriptor); void fw_core_remove_descriptor(struct fw_descriptor *desc) { mutex_lock(&card_mutex); list_del(&desc->link); descriptor_count--; if (desc->immediate > 0) descriptor_count--; update_config_roms(); mutex_unlock(&card_mutex); } EXPORT_SYMBOL(fw_core_remove_descriptor); static const char gap_count_table[] = { 63, 5, 7, 8, 10, 13, 16, 18, 21, 24, 26, 29, 32, 35, 37, 40 }; struct bm_data { struct fw_transaction t; struct { __be32 arg; __be32 data; } lock; u32 old; int rcode; struct completion done; }; static void complete_bm_lock(struct fw_card *card, int rcode, void *payload, size_t length, void *data) { struct bm_data *bmd = data; if (rcode == RCODE_COMPLETE) bmd->old = be32_to_cpu(*(__be32 *) payload); bmd->rcode = rcode; complete(&bmd->done); } static void fw_card_bm_work(struct work_struct *work) { struct fw_card *card = container_of(work, struct fw_card, work.work); struct fw_device *root_device; struct fw_node *root_node, *local_node; struct bm_data bmd; unsigned long flags; int root_id, new_root_id, irm_id, gap_count, generation, grace; int do_reset = 0; spin_lock_irqsave(&card->lock, flags); local_node = card->local_node; root_node = card->root_node; if (local_node == NULL) { spin_unlock_irqrestore(&card->lock, flags); return; } fw_node_get(local_node); fw_node_get(root_node); generation = card->generation; root_device = root_node->data; if (root_device) fw_device_get(root_device); root_id = root_node->node_id; grace = time_after(jiffies, card->reset_jiffies + DIV_ROUND_UP(HZ, 10)); if (card->bm_generation + 1 == generation || (card->bm_generation != generation && grace)) { /* * This first step is to figure out who is IRM and * then try to become bus manager. If the IRM is not * well defined (e.g. does not have an active link * layer or does not responds to our lock request, we * will have to do a little vigilante bus management. * In that case, we do a goto into the gap count logic * so that when we do the reset, we still optimize the * gap count. That could well save a reset in the * next generation. */ irm_id = card->irm_node->node_id; if (!card->irm_node->link_on) { new_root_id = local_node->node_id; fw_notify("IRM has link off, making local node (%02x) root.\n", new_root_id); goto pick_me; } bmd.lock.arg = cpu_to_be32(0x3f); bmd.lock.data = cpu_to_be32(local_node->node_id); spin_unlock_irqrestore(&card->lock, flags); init_completion(&bmd.done); fw_send_request(card, &bmd.t, TCODE_LOCK_COMPARE_SWAP, irm_id, generation, SCODE_100, CSR_REGISTER_BASE + CSR_BUS_MANAGER_ID, &bmd.lock, sizeof(bmd.lock), complete_bm_lock, &bmd); wait_for_completion(&bmd.done); if (bmd.rcode == RCODE_GENERATION) { /* * Another bus reset happened. Just return, * the BM work has been rescheduled. */ goto out; } if (bmd.rcode == RCODE_COMPLETE && bmd.old != 0x3f) /* Somebody else is BM, let them do the work. */ goto out; spin_lock_irqsave(&card->lock, flags); if (bmd.rcode != RCODE_COMPLETE) { /* * The lock request failed, maybe the IRM * isn't really IRM capable after all. Let's * do a bus reset and pick the local node as * root, and thus, IRM. */ new_root_id = local_node->node_id; fw_notify("BM lock failed, making local node (%02x) root.\n", new_root_id); goto pick_me; } } else if (card->bm_generation != generation) { /* * OK, we weren't BM in the last generation, and it's * less than 100ms since last bus reset. Reschedule * this task 100ms from now. */ spin_unlock_irqrestore(&card->lock, flags); schedule_delayed_work(&card->work, DIV_ROUND_UP(HZ, 10)); goto out; } /* * We're bus manager for this generation, so next step is to * make sure we have an active cycle master and do gap count * optimization. */ card->bm_generation = generation; if (root_device == NULL) { /* * Either link_on is false, or we failed to read the * config rom. In either case, pick another root. */ new_root_id = local_node->node_id; } else if (atomic_read(&root_device->state) != FW_DEVICE_RUNNING) { /* * If we haven't probed this device yet, bail out now * and let's try again once that's done. */ spin_unlock_irqrestore(&card->lock, flags); goto out; } else if (root_device->config_rom[2] & BIB_CMC) { /* * FIXME: I suppose we should set the cmstr bit in the * STATE_CLEAR register of this node, as described in * 1394-1995, 8.4.2.6. Also, send out a force root * packet for this node. */ new_root_id = root_id; } else { /* * Current root has an active link layer and we * successfully read the config rom, but it's not * cycle master capable. */ new_root_id = local_node->node_id; } pick_me: /* * Pick a gap count from 1394a table E-1. The table doesn't cover * the typically much larger 1394b beta repeater delays though. */ if (!card->beta_repeaters_present && root_node->max_hops < ARRAY_SIZE(gap_count_table)) gap_count = gap_count_table[root_node->max_hops]; else gap_count = 63; /* * Finally, figure out if we should do a reset or not. If we've * done less that 5 resets with the same physical topology and we * have either a new root or a new gap count setting, let's do it. */ if (card->bm_retries++ < 5 && (card->gap_count != gap_count || new_root_id != root_id)) do_reset = 1; spin_unlock_irqrestore(&card->lock, flags); if (do_reset) { fw_notify("phy config: card %d, new root=%x, gap_count=%d\n", card->index, new_root_id, gap_count); fw_send_phy_config(card, new_root_id, generation, gap_count); fw_core_initiate_bus_reset(card, 1); } out: if (root_device) fw_device_put(root_device); fw_node_put(root_node); fw_node_put(local_node); } static void flush_timer_callback(unsigned long data) { struct fw_card *card = (struct fw_card *)data; fw_flush_transactions(card); } void fw_card_initialize(struct fw_card *card, const struct fw_card_driver *driver, struct device *device) { static atomic_t index = ATOMIC_INIT(-1); kref_init(&card->kref); card->index = atomic_inc_return(&index); card->driver = driver; card->device = device; card->current_tlabel = 0; card->tlabel_mask = 0; card->color = 0; INIT_LIST_HEAD(&card->transaction_list); spin_lock_init(&card->lock); setup_timer(&card->flush_timer, flush_timer_callback, (unsigned long)card); card->local_node = NULL; INIT_DELAYED_WORK(&card->work, fw_card_bm_work); } EXPORT_SYMBOL(fw_card_initialize); int fw_card_add(struct fw_card *card, u32 max_receive, u32 link_speed, u64 guid) { u32 *config_rom; size_t length; card->max_receive = max_receive; card->link_speed = link_speed; card->guid = guid; /* * The subsystem grabs a reference when the card is added and * drops it when the driver calls fw_core_remove_card. */ fw_card_get(card); mutex_lock(&card_mutex); config_rom = generate_config_rom(card, &length); list_add_tail(&card->link, &card_list); mutex_unlock(&card_mutex); return card->driver->enable(card, config_rom, length); } EXPORT_SYMBOL(fw_card_add); /* * The next few functions implements a dummy driver that use once a * card driver shuts down an fw_card. This allows the driver to * cleanly unload, as all IO to the card will be handled by the dummy * driver instead of calling into the (possibly) unloaded module. The * dummy driver just fails all IO. */ static int dummy_enable(struct fw_card *card, u32 *config_rom, size_t length) { BUG(); return -1; } static int dummy_update_phy_reg(struct fw_card *card, int address, int clear_bits, int set_bits) { return -ENODEV; } static int dummy_set_config_rom(struct fw_card *card, u32 *config_rom, size_t length) { /* * We take the card out of card_list before setting the dummy * driver, so this should never get called. */ BUG(); return -1; } static void dummy_send_request(struct fw_card *card, struct fw_packet *packet) { packet->callback(packet, card, -ENODEV); } static void dummy_send_response(struct fw_card *card, struct fw_packet *packet) { packet->callback(packet, card, -ENODEV); } static int dummy_cancel_packet(struct fw_card *card, struct fw_packet *packet) { return -ENOENT; } static int dummy_enable_phys_dma(struct fw_card *card, int node_id, int generation) { return -ENODEV; } static struct fw_card_driver dummy_driver = { .name = "dummy", .enable = dummy_enable, .update_phy_reg = dummy_update_phy_reg, .set_config_rom = dummy_set_config_rom, .send_request = dummy_send_request, .cancel_packet = dummy_cancel_packet, .send_response = dummy_send_response, .enable_phys_dma = dummy_enable_phys_dma, }; void fw_core_remove_card(struct fw_card *card) { card->driver->update_phy_reg(card, 4, PHY_LINK_ACTIVE | PHY_CONTENDER, 0); fw_core_initiate_bus_reset(card, 1); mutex_lock(&card_mutex); list_del(&card->link); mutex_unlock(&card_mutex); /* Set up the dummy driver. */ card->driver = &dummy_driver; fw_destroy_nodes(card); flush_scheduled_work(); fw_flush_transactions(card); del_timer_sync(&card->flush_timer); fw_card_put(card); } EXPORT_SYMBOL(fw_core_remove_card); struct fw_card * fw_card_get(struct fw_card *card) { kref_get(&card->kref); return card; } EXPORT_SYMBOL(fw_card_get); static void release_card(struct kref *kref) { struct fw_card *card = container_of(kref, struct fw_card, kref); kfree(card); } /* * An assumption for fw_card_put() is that the card driver allocates * the fw_card struct with kalloc and that it has been shut down * before the last ref is dropped. */ void fw_card_put(struct fw_card *card) { kref_put(&card->kref, release_card); } EXPORT_SYMBOL(fw_card_put); int fw_core_initiate_bus_reset(struct fw_card *card, int short_reset) { int reg = short_reset ? 5 : 1; int bit = short_reset ? PHY_BUS_SHORT_RESET : PHY_BUS_RESET; return card->driver->update_phy_reg(card, reg, 0, bit); } EXPORT_SYMBOL(fw_core_initiate_bus_reset);