diff options
Diffstat (limited to 'drivers/firewire/core-card.c')
| -rw-r--r-- | drivers/firewire/core-card.c | 567 |
1 files changed, 567 insertions, 0 deletions
diff --git a/drivers/firewire/core-card.c b/drivers/firewire/core-card.c new file mode 100644 index 000000000000..ba6cd70b8518 --- /dev/null +++ b/drivers/firewire/core-card.c @@ -0,0 +1,567 @@ +/* + * 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(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 matches + * 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; +} + +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); +} + +static int set_broadcast_channel(struct device *dev, void *data) +{ + fw_device_set_broadcast_channel(fw_device(dev), (long)data); + return 0; +} + +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); + if (channel == 31) { + card->broadcast_channel_allocated = true; + device_for_each_child(card->device, (void *)(long)generation, + 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) +{ + int scheduled; + + fw_card_get(card); + scheduled = schedule_delayed_work(&card->work, delay); + if (!scheduled) + 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; + __be32 lock_data[2]; + + 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; + } + + lock_data[0] = cpu_to_be32(0x3f); + lock_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, + lock_data, sizeof(lock_data)); + + if (rcode == RCODE_GENERATION) + /* Another bus reset, BM work has been rescheduled. */ + goto out; + + if (rcode == RCODE_COMPLETE && + lock_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) +{ + u32 *config_rom; + size_t length; + int ret; + + card->max_receive = max_receive; + card->link_speed = link_speed; + card->guid = guid; + + mutex_lock(&card_mutex); + config_rom = generate_config_rom(card, &length); + list_add_tail(&card->link, &card_list); + mutex_unlock(&card_mutex); + + ret = card->driver->enable(card, config_rom, length); + if (ret < 0) { + mutex_lock(&card_mutex); + list_del(&card->link); + mutex_unlock(&card_mutex); + } + + return ret; +} +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 = { + .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) +{ + 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); + + /* Set up the dummy driver. */ + 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); |