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37 commits

Author SHA1 Message Date
Linus Torvalds
2f78d8e249 IEEE 1394 (FireWire) subsystem updates post v3.4:
- Fix mismatch between DMA mapping direction (was wrong) and DMA synchronization
     direction (was correct) of isochronous reception buffers of userspace drivers
     if vma-mapped for R/W access.  For example, libdc1394 was affected.
 
   - more consistent retry stategy in device discovery/ rediscovery, and improved
     failure diagnostics
 
   - various small cleanups, e.g. use SCSI layer's DMA mapping API in firewire-sbp2
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Merge tag 'firewire-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394

Pull IEEE 1394 (FireWire) subsystem updates from Stefan Richter:

 - Fix mismatch between DMA mapping direction (was wrong) and DMA
   synchronization direction (was correct) of isochronous reception
   buffers of userspace drivers if vma-mapped for R/W access.  For
   example, libdc1394 was affected.

 - more consistent retry stategy in device discovery/ rediscovery, and
   improved failure diagnostics

 - various small cleanups, e.g. use SCSI layer's DMA mapping API in
   firewire-sbp2

* tag 'firewire-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
  firewire: sbp2: document the absence of alignment requirements
  firewire: sbp2: remove superfluous blk_queue_max_segment_size() call
  firewire: sbp2: use scsi_dma_(un)map
  firewire: sbp2: give correct DMA device to scsi framework
  firewire: core: fw_device_refresh(): clean up error handling
  firewire: core: log config rom reading errors
  firewire: core: log error in case of failed bus manager lock
  firewire: move rcode_string() to core
  firewire: core: improve reread_config_rom() interface
  firewire: core: wait for inaccessible devices after bus reset
  firewire: ohci: omit spinlock IRQ flags where possible
  firewire: ohci: correct signedness of a local variable
  firewire: core: fix DMA mapping direction
  firewire: use module_pci_driver
2012-05-24 12:57:47 -07:00
Chris Boot
fc5f80b152 firewire: Move fw_card kref functions into linux/firewire.h
When writing a firewire driver that doesn't deal with struct fw_device
objects (e.g. it only publishes FireWire units and doesn't subscribe to
them), you likely need to keep referenced to struct fw_card objects so
that you can send messages to other nodes. This patch moves
fw_card_put(), fw_card_get() and fw_card_release() into the public
include/linux/firewire.h header instead of drivers/firewire/core.h, and
adds EXPORT_SYMBOL_GPL(fw_card_release).

The firewire-sbp-target module requires these so it can keep a reference
to the fw_card object in order that it can fetch ORBs to execute and
read/write related data and status information.

Signed-off-by: Chris Boot <bootc@bootc.net>
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-05-09 15:25:17 -07:00
Stefan Richter
0b6c4857f7 firewire: core: fix DMA mapping direction
Seen with recent libdc1394:  If a client mmap()s the buffer of an
isochronous reception buffer with PROT_READ|PROT_WRITE instead of just
PROT_READ, firewire-core sets the wrong DMA mapping direction during
buffer initialization.

The fix is to split fw_iso_buffer_init() into allocation and DMA mapping
and to perform the latter after both buffer and DMA context were
allocated.  Buffer allocation and context allocation may happen in any
order, but we need the context type (reception or transmission) in order
to set the DMA direction of the buffer.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-04-17 22:27:37 +02:00
Clemens Ladisch
d1bbd20972 firewire: allow explicit flushing of iso packet completions
Extend the kernel and userspace APIs to allow reporting all currently
completed isochronous packets, even if the next interrupt packet has not
yet been reached.  This is required to determine the status of the
packets at the end of a paused or stopped stream, and useful for more
precise synchronization of audio streams.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-03-18 22:15:39 +01:00
Stefan Richter
26b4950de1 firewire: core: prefix log messages with card name
Associate all log messages from firewire-core with the respective card
because some people have more than one card.  E.g.
    firewire_ohci 0000:04:00.0: added OHCI v1.10 device as card 0, 8 IR + 8 IT contexts, quirks 0x0
    firewire_ohci 0000:05:00.0: added OHCI v1.10 device as card 1, 8 IR + 8 IT contexts, quirks 0x0
    firewire_core: created device fw0: GUID 0814438400000389, S800
    firewire_core: phy config: new root=ffc1, gap_count=5
    firewire_core: created device fw1: GUID 0814438400000388, S800
    firewire_core: created device fw2: GUID 0001d202e06800d1, S800
turns into
    firewire_ohci 0000:04:00.0: added OHCI v1.10 device as card 0, 8 IR + 8 IT contexts, quirks 0x0
    firewire_ohci 0000:05:00.0: added OHCI v1.10 device as card 1, 8 IR + 8 IT contexts, quirks 0x0
    firewire_core 0000:04:00.0: created device fw0: GUID 0814438400000389, S800
    firewire_core 0000:04:00.0: phy config: new root=ffc1, gap_count=5
    firewire_core 0000:05:00.0: created device fw1: GUID 0814438400000388, S800
    firewire_core 0000:04:00.0: created device fw2: GUID 0001d202e06800d1, S800

This increases the module size slightly; to keep this in check, turn the
former printk wrapper macros into functions.  Their implementation is
largely copied from driver core's dev_printk counterparts.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-02-22 22:36:00 +01:00
Stefan Richter
2107622684 firewire: move fw_device reference counting from drivers to core
fw_unit device drivers invariably need to talk to the fw_unit's parent
(an fw_device) and grandparent (an fw_card).  firewire-core already
maintains an fw_card reference for the entire lifetime of an fw_device.
Likewise, let firewire-core maintain an fw_device reference for the
entire lifetime of an fw_unit so that fw_unit drivers don't have to.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-01-15 18:37:20 +01:00
Arun Sharma
60063497a9 atomic: use <linux/atomic.h>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:47 -07:00
Stefan Richter
105e53f863 firewire: sbp2: parallelize login, reconnect, logout
The struct sbp2_logical_unit.work items can all be executed in parallel
but are not reentrant.  Furthermore, reconnect or re-login work must be
executed in a WQ_MEM_RECLAIM workqueue.

Hence replace the old single-threaded firewire-sbp2 workqueue by a
concurrency-managed but non-reentrant workqueue with rescuer.
firewire-core already maintains one, hence use this one.

In earlier versions of this change, I observed occasional failures of
parallel INQUIRY to an Initio INIC-2430 FireWire 800 to dual IDE bridge.
More testing indicates that parallel INQUIRY is not actually a problem,
but too quick successions of logout and login + INQUIRY, e.g. a quick
sequence of cable plugout and plugin, can result in failed INQUIRY.
This does not seem to be something that should or could be addressed by
serialization.

Another dual-LU device to which I currently have access to, an
OXUF924DSB FireWire 800 to dual SATA bridge with firmware from MacPower,
has been successfully tested with this too.

This change is beneficial to environments with two or more FireWire
storage devices, especially if they are located on the same bus.
Management tasks that should be performed as soon and as quickly as
possible, especially reconnect, are no longer held up by tasks on other
devices that may take a long time, especially login with INQUIRY and sd
or sr driver probe.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-05-10 22:53:46 +02:00
Stefan Richter
6ea9e7bbfc firewire: core: use non-reentrant workqueue with rescuer
firewire-core manages the following types of work items:

fw_card.br_work:
  - resets the bus on a card and possibly sends a PHY packet before that
  - does not sleep for long or not at all
  - is scheduled via fw_schedule_bus_reset() by
      - firewire-ohci's pci_probe method
      - firewire-ohci's set_config_rom method, called by kernelspace
        protocol drivers and userspace drivers which add/remove
	Configuration ROM descriptors
      - userspace drivers which use the bus reset ioctl
      - itself if the last reset happened less than 2 seconds ago

fw_card.bm_work:
  - performs bus management duties
  - usually does not (but may in corner cases) sleep for long
  - is scheduled via fw_schedule_bm_work() by
      - firewire-ohci's self-ID-complete IRQ handler tasklet
      - firewire-core's fw_device.work instances whenever the root node
        device was (successfully or unsuccessfully) discovered,
	refreshed, or rediscovered
      - itself in case of resource allocation failures or in order to
        obey the 125ms bus manager arbitration interval

fw_device.work:
  - performs node probe, update, shutdown, revival, removal; including
    kernel driver probe, update, shutdown and bus reset notification to
    userspace drivers
  - usually sleeps moderately long, in corner cases very long
  - is scheduled by
      - firewire-ohci's self-ID-complete IRQ handler tasklet via the
        core's fw_node_event
      - firewire-ohci's pci_remove method via core's fw_destroy_nodes/
        fw_node_event
      - itself during retries, e.g. while a node is powering up

iso_resource.work:
  - accesses registers at the Isochronous Resource Manager node
  - usually does not (but may in corner cases) sleep for long
  - is scheduled via schedule_iso_resource() by
      - the owning userspace driver at addition and removal of the
        resource
      - firewire-core's fw_device.work instances after bus reset
      - itself in case of resource allocation if necessary to obey the
        1000ms reallocation period after bus reset

fw_card.br_work instances should not, and instances of the others must
not, be executed in parallel by multiple CPUs -- but were not protected
against that.  Hence allocate a non-reentrant workqueue for them.

fw_device.work may be used in the memory reclaim path in case of SBP-2
device updates.  Hence we need a workqueue with rescuer and cannot use
system_nrt_wq.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
2011-05-10 22:53:45 +02:00
Clemens Ladisch
13882a82ee firewire: optimize iso queueing by setting wake only after the last packet
When queueing iso packets, the run time is dominated by the two
MMIO accesses that set the DMA context's wake bit.  Because most
drivers submit packets in batches, we can save much time by
removing all but the last wakeup.

The internal kernel API is changed to require a call to
fw_iso_context_queue_flush() after a batch of queued packets.
The user space API does not change, so one call to
FW_CDEV_IOC_QUEUE_ISO must specify multiple packets to take
advantage of this optimization.

In my measurements, this patch reduces the time needed to queue
fifty skip packets from userspace to one sixth on a 2.5 GHz CPU,
or to one third at 800 MHz.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-05-10 22:53:45 +02:00
Clemens Ladisch
31ef9134eb ALSA: add LaCie FireWire Speakers/Griffin FireWave Surround driver
Add a driver for two playback-only FireWire devices based on the OXFW970
chip.

v2: better AMDTP API abstraction; fix fw_unit leak; small fixes
v3: cache the iPCR value
v4: FireWave constraints; fix fw_device reference counting;
    fix PCR caching; small changes and fixes
v5: volume/mute support; fix crashing due to pcm stop races
v6: fix build; one-channel volume for LaCie
v7: use signed values to make volume (range checks) work; fix function
    block IDs for volume/mute; always use channel 0 for LaCie volume

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Tested-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-03-15 08:42:22 +01:00
Clemens Ladisch
5b06db166c firewire: make PHY packet header format consistent
Change the header of PHY packets to be sent to include a pseudo
transaction code.  This makes the header consistent with that of
received PHY packets, and allows at_context_queue_packet() and
log_ar_at_event() to see the packet type directly instead of having
to deduce it from the header length or even from the header contents.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:14 +01:00
Stefan Richter
872e330e38 firewire: add isochronous multichannel reception
This adds the DMA context programming and userspace ABI for multichannel
reception, i.e. for listening on multiple channel numbers by means of a
single DMA context.

The use case is reception of more streams than there are IR DMA units
offered by the link layer.  This is already implemented by the older
ohci1394 + ieee1394 + raw1394 stack.  And as discussed recently on
linux1394-devel, this feature is occasionally used in practice.

The big drawbacks of this mode are that buffer layout and interrupt
generation necessarily differ from single-channel reception:  Headers
and trailers are not stripped from packets, packets are not aligned with
buffer chunks, interrupts are per buffer chunk, not per packet.

These drawbacks also cause a rather hefty code footprint to support this
rarely used OHCI-1394 feature.  (367 lines added, among them 94 lines of
added userspace ABI documentation.)

This implementation enforces that a multichannel reception context may
only listen to channels to which no single-channel context on the same
link layer is presently listening to.  OHCI-1394 would allow to overlay
single-channel contexts by the multi-channel context, but this would be
a departure from the present first-come-first-served policy of IR
context creation.

The implementation is heavily based on an earlier one by Jay Fenlason.
Thanks Jay.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-29 23:09:18 +02:00
Stefan Richter
cc550216ae firewire: cdev: add PHY pinging
This extends the FW_CDEV_IOC_SEND_PHY_PACKET ioctl() for /dev/fw* to be
useful for ping time measurements.  One application for it would be gap
count optimization in userspace that is based on ping times rather than
hop count.  (The latter is implemented in firewire-core itself but is
not applicable to beta PHYs that act as repeater.)

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:28 +02:00
Stefan Richter
bf54e1462b firewire: cdev: add PHY packet reception
Add an FW_CDEV_IOC_RECEIVE_PHY_PACKETS ioctl() and
FW_CDEV_EVENT_PHY_PACKET_RECEIVED poll()/read() event for /dev/fw*.
This can be used to get information from remote PHYs by remote access
PHY packets.

This is also the 2nd half of the functionality (the receive part) to
support a userspace implementation of a VersaPHY transaction layer.

Safety considerations:

  - PHY packets are generally broadcasts, hence some kind of elevated
    privileges should be required of a process to be able to listen in
    on PHY packets.  This implementation assumes that a process that is
    allowed to open the /dev/fw* of a local node does have this
    privilege.

    There was an inconclusive discussion about introducing POSIX
    capabilities as a means to check for user privileges for these
    kinds of operations.

Other limitations:

  - PHY packet reception may be switched on by ioctl() but cannot be
    switched off again.  It would be trivial to provide an off switch,
    but this is not worth the code.  The client should simply close()
    the fd then, or just ignore further events.

  - For sake of simplicity of API and kernel-side implementation, no
    filter per packet content is provided.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:28 +02:00
Stefan Richter
02d37bed18 firewire: core: integrate software-forced bus resets with bus management
Bus resets which are triggered
  - by the kernel drivers after updates of the local nodes' config ROM,
  - by userspace software via ioctl
shall be deferred until after >=2 seconds after the last bus reset.

If multiple modifications of the local nodes' config ROM happen in a row,
only a single bus reset should happen after them.

When the local node's link goes from inactive to active or vice versa,
and at the two occasions of bus resets mentioned above --- and if the
current gap count differs from 63 --- the bus reset should be preceded
by a PHY configuration packet that reaffirms the gap count.  Otherwise a
bus manager would have to reset the bus again right after that.

This is necessary to promote bus stability, e.g. leave grace periods for
allocations and reallocations of isochronous channels and bandwidth,
SBP-2 reconnections etc.; see IEEE 1394 clause 8.2.1.

This change implements all of the above by moving bus reset initiation
into a delayed work (except for bus resets which are triggered by the
bus manager workqueue job and are performed there immediately).  It
comes with a necessary addition to the card driver methods that allows
to get the current gap count from PHY registers.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-13 09:58:27 +02:00
Stefan Richter
0fcff4e393 firewire: rename CSR access driver methods
Rather than "read a Control and Status Registers (CSR) Architecture
register" I prefer to say "read a Control and Status Register".

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
c8a94ded57 firewire: normalize STATE_CLEAR/SET CSR access interface
Push the maintenance of STATE_CLEAR/SET.abdicate down into the card
driver.  This way, the read/write_csr_reg driver method works uniformly
across all CSR offsets.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
db3c9cc105 firewire: replace get_features card driver hook
by feature variables in the fw_card struct.  The hook appeared to be an
unnecessary abstraction in the card driver interface.

Cleaner would be to pass those feature flags as arguments to
fw_card_initialize() or fw_card_add(), but the FairnessControl register
is in the SCLK domain and may therefore not be accessible while Link
Power Status is off, i.e. before the card->driver->enable call from
fw_card_add().

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Clemens Ladisch
e91b2787d0 firewire: allocate broadcast channel in hardware
On OHCI 1.1 controllers, let the hardware allocate the broadcast channel
automatically.  This removes a theoretical race condition directly after
a bus reset where it could be possible to read the channel allocation
register with channel 31 still being unallocated.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:40:49 +02:00
Clemens Ladisch
7e0e314f19 firewire: core: add CSR abdicate support
Implement the abdicate bit, which is required for bus manager
capable nodes and tested by the Base 1394 Test Suite.

Finally, something to do at a command reset!  :-)

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:37:15 +02:00
Clemens Ladisch
4ffb7a6a06 firewire: add CSR cmstr support
Implement the cmstr bit, which is required for cycle master capable
nodes and tested for by the Base 1394 Test Suite.

This bit allows the bus master to disable cycle start packets; there are
bus master implementations that actually do this.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:36:37 +02:00
Clemens Ladisch
a1a1132bd8 firewire: add CSR PRIORITY_BUDGET support
If supported by the OHCI controller, implement the PRIORITY_BUDGET
register, which is required for nodes that can use asynchronous
priority arbitration.

To allow the core to determine what features the lowlevel device
supports, add a new card driver callback.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:35:06 +02:00
Clemens Ladisch
506f1a3193 firewire: add CSR NODE_IDS support
The NODE_IDS register, and especially its bus_id field, is quite
useless because 1394.1 requires that the bus_id field always stays
0x3ff.  However, the 1394 specification requires this register on all
transaction capable nodes, and the Base 1394 Test Suite tests for it,
so we better implement it.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:25:19 +02:00
Clemens Ladisch
60d32970c5 firewire: add read_csr_reg driver callback
To prepare for the following additions of more OHCI-implemented CSR
registers, replace the get_cycle_time driver callback with a generic
CSR register callback.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:24:35 +02:00
Clemens Ladisch
a10c0ce760 firewire: check cdev response length
Add a check that the data length in the SEND_RESPONSE ioctl is correct.
Incidentally, this also fixes the previously wrong response length of
software-handled lock requests.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-09 19:42:18 +02:00
Clemens Ladisch
5c40cbfefa firewire: core: use separate timeout for each transaction
Using a single timeout for all transaction that need to be flushed does
not work if the submission of new transactions can defer the timeout
indefinitely into the future.  We need to have timeouts that do not
change due to other transactions; the simplest way to do this is with a
separate timer for each transaction.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (+ one lockdep annotation)
2010-05-19 00:26:30 +02:00
Clemens Ladisch
925e7a6504 firewire: ohci: enable 1394a enhancements
The OHCI spec says that, if the programPhyEnable bit is set, the driver
is responsible for configuring the IEEE1394a enhancements within the PHY
and the link consistently.  So do this.

Also add a quirk to allow disabling these enhancements; this is needed
for the TSB12LV22 where ack accelerations are buggy (erratum b).

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-10 16:51:14 +02:00
Clemens Ladisch
e7014dada0 firewire: ohci: do not clear PHY interrupt status inadvertently
The interrupt status bits in PHY register 5 are cleared by writing a one
bit.  To avoid clearing them unadvertently, do not write them back when
they were read as set, but only when they have been explicitly requested
to be set.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-10 16:51:14 +02:00
Stefan Richter
168cf9af69 firewire: remove incomplete Bus_Time CSR support
The current implementation of Bus_Time read access was buggy since it
did not ensure that Bus_Time.second_count_hi and second_count_lo came
from the same 128 seconds period.

Reported-by: Håkan Johansson <f96hajo@chalmers.se>

Instead of a fix, remove Bus_Time register support altogether.  The spec
requires all cycle master capable nodes to implement this (all Linux
nodes are cycle master capable) while it also says that it "may" be
initialized by the bus manager or by the IRM standing in for a bus
manager.  (Neither Linux' firewire-core nor ieee1394 nodemgr implement
this.)

Since we cannot rely on Bus_Time having been initialized by a bus
manager, it is better to return an error instead of a nonsensical value
on a read request to Bus_Time.

Alternatively, we could fix the Bus_Time read integrity bug _and_
implement (a) cycle master's write support of the register as well as
(b) bus manager's Bus_Time initialization service, i.e. preservation of
the Bus_Time when the cycle master node of a bus changes.  However, that
would be quite some code for a feature that is unreliable to begin with
and very likely unused in practice.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-02-20 22:33:14 +01:00
Stefan Richter
cb7c96da36 firewire: core: optimize Topology Map creation
The Topology Map of the local node was created in CPU byte order,
then a temporary big endian copy was created to compute the CRC,
and when a read request to the Topology Map arrived it had to be
converted to big endian byte order again.

We now generate it in big endian byte order in the first place.
This also rids us of 1000 bytes stack usage in tasklet context.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-10-14 23:10:48 +02:00
Stefan Richter
8e85973efc firewire: optimize config ROM creation
The config ROM image of the local node was created in CPU byte order,
then a temporary big endian copy was created to compute the CRC, and
finally the card driver created its own big endian copy.

We now generate it in big endian byte order in the first place to avoid
one byte order conversion and the temporary on-stack copy of the ROM
image (1000 bytes stack usage in process context).  Furthermore, two
1000 bytes memset()s are replaced by one 1000 bytes - ROM length sized
memset.

The trivial fw_memcpy_{from,to}_be32() helpers are now superfluous and
removed.  The newly added __compute_block_crc() function will be folded
into fw_compute_block_crc() in a subsequent change.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-10-14 23:10:48 +02:00
Stefan Richter
18668ff9a3 firewire: core: header file cleanup
fw_card_get, fw_card_put, fw_card_release are currently not exported for
use outside the firewire-core.  Move their definitions/ declarations
from the subsystem header file to the core header file.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-09-12 14:48:40 +02:00
Stefan Richter
6fdc037094 firewire: core: do not DMA-map stack addresses
The DMA mapping API cannot map on-stack addresses, as explained in
Documentation/DMA-mapping.txt.  Convert the two cases of on-stack packet
payload buffers in firewire-core (payload of lock requests in the bus
manager work and in iso resource management) to slab-allocated memory.

There are a number on-stack buffers for quadlet write or quadlet read
requests in firewire-core and firewire-sbp2.  These are harmless; they
are copied to/ from card driver internal DMA buffers since quadlet
payloads are inlined with packet headers.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-25 19:42:36 +02:00
Jay Fenlason
c76acec6d5 firewire: add IPv4 support
Implement IPv4 over IEEE 1394 as per RFC 2734 for the newer firewire
stack.  This feature has only been present in the older ieee1394 stack
via the eth1394 driver.

Still to do:
  - fix ipv4_priv and ipv4_node lifetime logic
  - fix determination of speeds and max payloads
  - fix bus reset handling
  - fix unaligned memory accesses
  - fix coding style
  - further testing/ improvement of fragment reassembly
  - perhaps multicast support

Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (rebased, copyright note, changelog)
2009-06-14 14:26:28 +02:00
Stefan Richter
099d54143e firewire: core: prepare for non-core children of card devices
The IP-over-1394 driver will add child devices beneath card devices
which are not of type fw_device.  Hence firewire-core's callbacks in
device_for_each_child() and device_find_child() need to check for the
device type now.

Initial version written by Jay Fenlason.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-06 21:45:50 +02:00
Stefan Richter
77c9a5daa9 firewire: reorganize header files
The three header files of firewire-core, i.e.
 "drivers/firewire/fw-device.h",
 "drivers/firewire/fw-topology.h",
 "drivers/firewire/fw-transaction.h",
are replaced by
 "drivers/firewire/core.h",
 "include/linux/firewire.h".

The latter includes everything which a firewire high-level driver (like
firewire-sbp2) needs besides linux/firewire-constants.h, while core.h
contains the rest which is needed by firewire-core itself and by low-
level drivers (card drivers) like firewire-ohci.

High-level drivers can now also reside outside of drivers/firewire
without having to add drivers/firewire to the header file search path in
makefiles.  At least the firedtv driver will be such a driver.

I also considered to spread the contents of core.h over several files,
one for each .c file where the respective implementation resides.  But
it turned out that most core .c files will end up including most of the
core .h files.  Also, the combined core.h isn't unreasonably big, and it
will lose more of its contents to linux/firewire.h anyway soon when more
firewire drivers are added.  (IP-over-1394, firedtv, and there are plans
for one or two more.)

Furthermore, fw-ohci.h is renamed to ohci.h.  The name of core.h and
ohci.h is chosen with regard to name changes of the .c files in a
follow-up change.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-05 16:26:18 +02:00