linux/drivers/firewire/core-card.c
Clemens Ladisch dd5eeb99f4 firewire: core: increase default SPLIT_TIMEOUT value
The SPLIT_TIMEOUT mechanism is intended to detect requests that somehow
got lost.  However, when the timeout value is too low, transactions that
could have been completed successfully will be cancelled.  Furthermore,
there are chips whose firmwares ignore the configured split timeout and
send late split response; known examples are the DM1x00 (BeBoB), TCD22x0
(DICE), and some OXUF936QSE firmwares.

This patch changes the default timeout to two seconds, which happens to
be the default on other OSes, too.

Actual lost requests are extremely rare, so there should be no practical
downside to increasing the split timeout even on devices that work
correctly.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-03-20 16:45:24 +01:00

678 lines
19 KiB
C

/*
* 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/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_BUS_NAME 0x31333934 /* "1394" */
#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_IRMC ((1) << 31)
#define NODE_CAPABILITIES 0x0c0083c0 /* per IEEE 1394 clause 8.3.2.6.5.2 */
/*
* IEEE-1394 specifies a default SPLIT_TIMEOUT value of 800 cycles (100 ms),
* but we have to make it longer because there are many devices whose firmware
* is just too slow for that.
*/
#define DEFAULT_SPLIT_TIMEOUT (2 * 8000)
#define CANON_OUI 0x000085
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(BIB_BUS_NAME);
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_IRMC);
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(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 int reset_bus(struct fw_card *card, bool 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);
}
void fw_schedule_bus_reset(struct fw_card *card, bool delayed, bool short_reset)
{
/* We don't try hard to sort out requests of long vs. short resets. */
card->br_short = short_reset;
/* Use an arbitrary short delay to combine multiple reset requests. */
fw_card_get(card);
if (!schedule_delayed_work(&card->br_work,
delayed ? DIV_ROUND_UP(HZ, 100) : 0))
fw_card_put(card);
}
EXPORT_SYMBOL(fw_schedule_bus_reset);
static void br_work(struct work_struct *work)
{
struct fw_card *card = container_of(work, struct fw_card, br_work.work);
/* Delay for 2s after last reset per IEEE 1394 clause 8.2.1. */
if (card->reset_jiffies != 0 &&
time_before64(get_jiffies_64(), card->reset_jiffies + 2 * HZ)) {
if (!schedule_delayed_work(&card->br_work, 2 * HZ))
fw_card_put(card);
return;
}
fw_send_phy_config(card, FW_PHY_CONFIG_NO_NODE_ID, card->generation,
FW_PHY_CONFIG_CURRENT_GAP_COUNT);
reset_bus(card, card->br_short);
fw_card_put(card);
}
static void allocate_broadcast_channel(struct fw_card *card, int generation)
{
int channel, bandwidth = 0;
if (!card->broadcast_channel_allocated) {
fw_iso_resource_manage(card, generation, 1ULL << 31,
&channel, &bandwidth, true,
card->bm_transaction_data);
if (channel != 31) {
fw_notify("failed to allocate broadcast channel\n");
return;
}
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->bm_work, delay))
fw_card_put(card);
}
static void bm_work(struct work_struct *work)
{
struct fw_card *card = container_of(work, struct fw_card, bm_work.work);
struct fw_device *root_device, *irm_device;
struct fw_node *root_node;
int root_id, new_root_id, irm_id, bm_id, local_id;
int gap_count, generation, grace, rcode;
bool do_reset = false;
bool root_device_is_running;
bool root_device_is_cmc;
bool irm_is_1394_1995_only;
bool keep_this_irm;
spin_lock_irq(&card->lock);
if (card->local_node == NULL) {
spin_unlock_irq(&card->lock);
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;
irm_device = card->irm_node->data;
irm_is_1394_1995_only = irm_device && irm_device->config_rom &&
(irm_device->config_rom[2] & 0x000000f0) == 0;
/* Canon MV5i works unreliably if it is not root node. */
keep_this_irm = irm_device && irm_device->config_rom &&
irm_device->config_rom[3] >> 8 == CANON_OUI;
root_id = root_node->node_id;
irm_id = card->irm_node->node_id;
local_id = card->local_node->node_id;
grace = time_after64(get_jiffies_64(),
card->reset_jiffies + DIV_ROUND_UP(HZ, 8));
if ((is_next_generation(generation, card->bm_generation) &&
!card->bm_abdicate) ||
(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("%s, making local node (%02x) root.\n",
"IRM has link off", new_root_id);
goto pick_me;
}
if (irm_is_1394_1995_only && !keep_this_irm) {
new_root_id = local_id;
fw_notify("%s, making local node (%02x) root.\n",
"IRM is not 1394a compliant", 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_irq(&card->lock);
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, 8);
if (rcode == RCODE_GENERATION)
/* Another bus reset, BM work has been rescheduled. */
goto out;
bm_id = be32_to_cpu(card->bm_transaction_data[0]);
spin_lock_irq(&card->lock);
if (rcode == RCODE_COMPLETE && generation == card->generation)
card->bm_node_id =
bm_id == 0x3f ? local_id : 0xffc0 | bm_id;
spin_unlock_irq(&card->lock);
if (rcode == RCODE_COMPLETE && bm_id != 0x3f) {
/* Somebody else is BM. Only act as IRM. */
if (local_id == irm_id)
allocate_broadcast_channel(card, generation);
goto out;
}
if (rcode == RCODE_SEND_ERROR) {
/*
* We have been unable to send the lock request due to
* some local problem. Let's try again later and hope
* that the problem has gone away by then.
*/
fw_schedule_bm_work(card, DIV_ROUND_UP(HZ, 8));
goto out;
}
spin_lock_irq(&card->lock);
if (rcode != RCODE_COMPLETE && !keep_this_irm) {
/*
* 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("%s, making local node (%02x) root.\n",
"BM lock failed", 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_irq(&card->lock);
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_irq(&card->lock);
goto out;
} else if (root_device_is_cmc) {
/*
* We will send out a force root packet for this
* node as part of the gap count optimization.
*/
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_irq(&card->lock);
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);
reset_bus(card, true);
/* Will allocate broadcast channel after the reset. */
goto out;
}
if (root_device_is_cmc) {
/*
* Make sure that the cycle master sends cycle start packets.
*/
card->bm_transaction_data[0] = cpu_to_be32(CSR_STATE_BIT_CMSTR);
rcode = fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
root_id, generation, SCODE_100,
CSR_REGISTER_BASE + CSR_STATE_SET,
card->bm_transaction_data, 4);
if (rcode == RCODE_GENERATION)
goto out;
}
if (local_id == irm_id)
allocate_broadcast_channel(card, generation);
out:
fw_node_put(root_node);
out_put_card:
fw_card_put(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->split_timeout_hi = DEFAULT_SPLIT_TIMEOUT / 8000;
card->split_timeout_lo = (DEFAULT_SPLIT_TIMEOUT % 8000) << 19;
card->split_timeout_cycles = DEFAULT_SPLIT_TIMEOUT;
card->split_timeout_jiffies =
DIV_ROUND_UP(DEFAULT_SPLIT_TIMEOUT * HZ, 8000);
card->color = 0;
card->broadcast_channel = BROADCAST_CHANNEL_INITIAL;
kref_init(&card->kref);
init_completion(&card->done);
INIT_LIST_HEAD(&card->transaction_list);
INIT_LIST_HEAD(&card->phy_receiver_list);
spin_lock_init(&card->lock);
card->local_node = NULL;
INIT_DELAYED_WORK(&card->br_work, br_work);
INIT_DELAYED_WORK(&card->bm_work, 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.
*
* .read/write_csr() should never be called anymore after the dummy driver
* was bound since they are only used within request handler context.
* .set_config_rom() is never called since the card is taken out of card_list
* before switching to the dummy driver.
*/
static int dummy_read_phy_reg(struct fw_card *card, int address)
{
return -ENODEV;
}
static int dummy_update_phy_reg(struct fw_card *card, int address,
int clear_bits, int set_bits)
{
return -ENODEV;
}
static void dummy_send_request(struct fw_card *card, struct fw_packet *packet)
{
packet->callback(packet, card, RCODE_CANCELLED);
}
static void dummy_send_response(struct fw_card *card, struct fw_packet *packet)
{
packet->callback(packet, card, RCODE_CANCELLED);
}
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_iso_context *dummy_allocate_iso_context(struct fw_card *card,
int type, int channel, size_t header_size)
{
return ERR_PTR(-ENODEV);
}
static int dummy_start_iso(struct fw_iso_context *ctx,
s32 cycle, u32 sync, u32 tags)
{
return -ENODEV;
}
static int dummy_set_iso_channels(struct fw_iso_context *ctx, u64 *channels)
{
return -ENODEV;
}
static int dummy_queue_iso(struct fw_iso_context *ctx, struct fw_iso_packet *p,
struct fw_iso_buffer *buffer, unsigned long payload)
{
return -ENODEV;
}
static const struct fw_card_driver dummy_driver_template = {
.read_phy_reg = dummy_read_phy_reg,
.update_phy_reg = dummy_update_phy_reg,
.send_request = dummy_send_request,
.send_response = dummy_send_response,
.cancel_packet = dummy_cancel_packet,
.enable_phys_dma = dummy_enable_phys_dma,
.allocate_iso_context = dummy_allocate_iso_context,
.start_iso = dummy_start_iso,
.set_iso_channels = dummy_set_iso_channels,
.queue_iso = dummy_queue_iso,
};
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_schedule_bus_reset(card, false, true);
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));
}
EXPORT_SYMBOL(fw_core_remove_card);