/* * Copyright (C) 2005-2007 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/crc-itu-t.h> #include <linux/device.h> #include <linux/errno.h> #include <linux/firewire.h> #include <linux/firewire-constants.h> #include <linux/jiffies.h> #include <linux/kernel.h> #include <linux/kref.h> #include <linux/list.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/spinlock.h> #include <linux/timer.h> #include <linux/workqueue.h> #include <asm/atomic.h> #include <asm/byteorder.h> #include "core.h" int fw_compute_block_crc(__be32 *block) { int length; u16 crc; length = (be32_to_cpu(block[0]) >> 16) & 0xff; crc = crc_itu_t(0, (u8 *)&block[1], length * 4); *block |= cpu_to_be32(crc); return length; } static DEFINE_MUTEX(card_mutex); static LIST_HEAD(card_list); static LIST_HEAD(descriptor_list); static int descriptor_count; static __be32 tmp_config_rom[256]; /* ROM header, bus info block, root dir header, capabilities = 7 quadlets */ static size_t config_rom_length = 1 + 4 + 1 + 1; #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 void generate_config_rom(struct fw_card *card, __be32 *config_rom) { struct fw_descriptor *desc; int i, j, k, 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 matches * the version stored in the OHCI registers. */ config_rom[0] = cpu_to_be32( BIB_CRC_LENGTH(4) | BIB_INFO_LENGTH(4) | BIB_CRC(0)); config_rom[1] = cpu_to_be32(0x31333934); config_rom[2] = cpu_to_be32( 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] = cpu_to_be32(card->guid >> 32); config_rom[4] = cpu_to_be32(card->guid); /* Generate root directory. */ config_rom[6] = cpu_to_be32(0x0c0083c0); /* node capabilities */ i = 7; j = 7 + descriptor_count; /* Generate root directory entries for descriptors. */ list_for_each_entry (desc, &descriptor_list, link) { if (desc->immediate > 0) config_rom[i++] = cpu_to_be32(desc->immediate); config_rom[i] = cpu_to_be32(desc->key | (j - i)); i++; j += desc->length; } /* Update root directory length. */ config_rom[5] = cpu_to_be32((i - 5 - 1) << 16); /* End of root directory, now copy in descriptors. */ list_for_each_entry (desc, &descriptor_list, link) { for (k = 0; k < desc->length; k++) config_rom[i + k] = cpu_to_be32(desc->data[k]); 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); WARN_ON(j != config_rom_length); } static void update_config_roms(void) { struct fw_card *card; list_for_each_entry (card, &card_list, link) { generate_config_rom(card, tmp_config_rom); card->driver->set_config_rom(card, tmp_config_rom, config_rom_length); } } static size_t required_space(struct fw_descriptor *desc) { /* descriptor + entry into root dir + optional immediate entry */ return desc->length + 1 + (desc->immediate > 0 ? 1 : 0); } int fw_core_add_descriptor(struct fw_descriptor *desc) { size_t i; int ret; /* * 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); if (config_rom_length + required_space(desc) > 256) { ret = -EBUSY; } else { list_add_tail(&desc->link, &descriptor_list); config_rom_length += required_space(desc); descriptor_count++; if (desc->immediate > 0) descriptor_count++; update_config_roms(); ret = 0; } mutex_unlock(&card_mutex); return ret; } EXPORT_SYMBOL(fw_core_add_descriptor); void fw_core_remove_descriptor(struct fw_descriptor *desc) { mutex_lock(&card_mutex); list_del(&desc->link); config_rom_length -= required_space(desc); descriptor_count--; if (desc->immediate > 0) descriptor_count--; update_config_roms(); mutex_unlock(&card_mutex); } EXPORT_SYMBOL(fw_core_remove_descriptor); static void allocate_broadcast_channel(struct fw_card *card, int generation) { int channel, bandwidth = 0; fw_iso_resource_manage(card, generation, 1ULL << 31, &channel, &bandwidth, true, card->bm_transaction_data); if (channel == 31) { card->broadcast_channel_allocated = true; device_for_each_child(card->device, (void *)(long)generation, fw_device_set_broadcast_channel); } } static const char gap_count_table[] = { 63, 5, 7, 8, 10, 13, 16, 18, 21, 24, 26, 29, 32, 35, 37, 40 }; void fw_schedule_bm_work(struct fw_card *card, unsigned long delay) { fw_card_get(card); if (!schedule_delayed_work(&card->work, delay)) fw_card_put(card); } 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; unsigned long flags; int root_id, new_root_id, irm_id, local_id; int gap_count, generation, grace, rcode; bool do_reset = false; bool root_device_is_running; bool root_device_is_cmc; spin_lock_irqsave(&card->lock, flags); if (card->local_node == NULL) { spin_unlock_irqrestore(&card->lock, flags); goto out_put_card; } generation = card->generation; root_node = card->root_node; fw_node_get(root_node); root_device = root_node->data; root_device_is_running = root_device && atomic_read(&root_device->state) == FW_DEVICE_RUNNING; root_device_is_cmc = root_device && root_device->cmc; root_id = root_node->node_id; irm_id = card->irm_node->node_id; local_id = card->local_node->node_id; grace = time_after(jiffies, card->reset_jiffies + DIV_ROUND_UP(HZ, 8)); if (is_next_generation(generation, card->bm_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. */ if (!card->irm_node->link_on) { new_root_id = local_id; fw_notify("IRM has link off, making local node (%02x) root.\n", new_root_id); goto pick_me; } card->bm_transaction_data[0] = cpu_to_be32(0x3f); card->bm_transaction_data[1] = cpu_to_be32(local_id); spin_unlock_irqrestore(&card->lock, flags); rcode = fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP, irm_id, generation, SCODE_100, CSR_REGISTER_BASE + CSR_BUS_MANAGER_ID, card->bm_transaction_data, sizeof(card->bm_transaction_data)); if (rcode == RCODE_GENERATION) /* Another bus reset, BM work has been rescheduled. */ goto out; if (rcode == RCODE_COMPLETE && card->bm_transaction_data[0] != cpu_to_be32(0x3f)) { /* Somebody else is BM. Only act as IRM. */ if (local_id == irm_id) allocate_broadcast_channel(card, generation); goto out; } spin_lock_irqsave(&card->lock, flags); if (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_id; fw_notify("BM lock failed, making local node (%02x) root.\n", new_root_id); goto pick_me; } } else if (card->bm_generation != generation) { /* * We weren't BM in the last generation, and the last * bus reset is less than 125ms ago. Reschedule this job. */ spin_unlock_irqrestore(&card->lock, flags); fw_schedule_bm_work(card, DIV_ROUND_UP(HZ, 8)); 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_id; } else if (!root_device_is_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_is_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_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 have * done less than 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 = true; 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); /* Will allocate broadcast channel after the reset. */ } else { if (local_id == irm_id) allocate_broadcast_channel(card, generation); } out: fw_node_put(root_node); out_put_card: fw_card_put(card); } 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); card->index = atomic_inc_return(&index); card->driver = driver; card->device = device; card->current_tlabel = 0; card->tlabel_mask = 0; card->color = 0; card->broadcast_channel = BROADCAST_CHANNEL_INITIAL; kref_init(&card->kref); init_completion(&card->done); 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) { int ret; card->max_receive = max_receive; card->link_speed = link_speed; card->guid = guid; mutex_lock(&card_mutex); generate_config_rom(card, tmp_config_rom); ret = card->driver->enable(card, tmp_config_rom, config_rom_length); if (ret == 0) list_add_tail(&card->link, &card_list); mutex_unlock(&card_mutex); return ret; } EXPORT_SYMBOL(fw_card_add); /* * The next few functions implement a dummy driver that is used 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 (and failed) by the dummy driver * instead of calling into the module. Only functions for iso context * shutdown still need to be provided by the card driver. */ static int dummy_enable(struct fw_card *card, const __be32 *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, const __be32 *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 const struct fw_card_driver dummy_driver_template = { .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_card_release(struct kref *kref) { struct fw_card *card = container_of(kref, struct fw_card, kref); complete(&card->done); } void fw_core_remove_card(struct fw_card *card) { struct fw_card_driver dummy_driver = dummy_driver_template; 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_init(&card->link); mutex_unlock(&card_mutex); /* Switch off most of the card driver interface. */ dummy_driver.free_iso_context = card->driver->free_iso_context; dummy_driver.stop_iso = card->driver->stop_iso; card->driver = &dummy_driver; fw_destroy_nodes(card); /* Wait for all users, especially device workqueue jobs, to finish. */ fw_card_put(card); wait_for_completion(&card->done); WARN_ON(!list_empty(&card->transaction_list)); del_timer_sync(&card->flush_timer); } EXPORT_SYMBOL(fw_core_remove_card); 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);