Add a loop to wait for the controller to finish a locally-initiated CSR
lock operation. Google shows some occurrences of the "swap not done
yet" message which might indicate that some OHCI controllers are not
fast enough to do the lock/swap in the time needed for one PCI access.
This also correctly handles the case where the lock operation did not
finish, instead of silently returning an uninitialized value.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
We must compute the offset from the CSR register base with the
full 48 address bits to prevent matching with addresses whose
lower 32 bits happen to be equal with one of the specially
handled registers.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
1) Clean up two function names: The ohci_ prefix is only used in names
of fw_card_driver hooks. There were two unnecessary exceptions.
2) Replace empty macros by empty inline functions so that call parameter
type checking is available in #ifndef'd builds.
3) CONFIG_FIREWIRE_OHCI_DEBUG is currently a hidden kconfig variable,
hence is not going to be switched off by anybody. Still, it can be
switched off but then compilation will fail in ohci_enable() at the
expression param_debug & OHCI_PARAM_DEBUG_BUSRESETS. Add the necessary
definitions in the nonstandard case.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Rather than having the arbitrary msleep(2) pause, let read_phy_reg()
loop until the link--phy access was finished.
Factor write_phy_reg() out of ohci_update_phy_reg() and of
read_paged_phy_reg() and let it loop too until the link--phy access was
finished.
Like in the older ohci1394 driver, a timeout of 100 milliseconds is
chosen. Unlike the old driver, we sleep instead of busy-wait in each
waiting loop iteration. Instead of a loop, the waiting could probably
also be implemented interrupt driven, but why bother. It would require
up and running interrupt handling before the link was fully configured
and enabled.
Also modify functions a bit: Error return and value return can be
combined in read_phy_reg() since the domain of values is only u8.
Likewise in read_paged_phy_reg().
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
On TI chips (OHCI-Lynx and later), enable link enhancements features
that TI recommends to be used. None of these are required for proper
operation, but they are safe and nice to have.
In theory, these bits should have been set by default, but in practice,
some BIOS/EEPROM writers apparently do not read the datasheet, or get
spooked by names like "unfair".
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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>
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>
Move the register reading code from ohci_update_phy_reg() into
a function which can be used separately.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Among the many entries in the TSB12LV22 errata list (TI literature
number SLLS312) is the following:
PCI Slave reads of the Cycle Timer register may occasionally get an
incorrect value.
Software may be able to validate value by reading the register
multiple times rapidly and evaluating for a reasonable difference.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de> (untested)
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (added #define)
by the number of available isochronous DMA contexts and active quirks
which is occasionally useful information.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This bug was present in firewire-ohci since day one: The number of
available isochronous receive DMA contexts was mixed up with that of
available isochronous transmit DMA contexts.
This is harmless on a few chips which offer the same number of contexts
in both directions, but most chips nowadays implement only the standard
minimum of 4 IR contexts, but 8 IT contexts. If a user attempted to run
a lot of IR contexts at once, results with more than four were therefore
unpredictable. I suppose the controller would simply refuse to start
DMA of any unimplemented context.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This way, we can advise users of precompiled kernel packages to test
existing quirk fixes on chips which have not been listed yet, without
them having to build a kernel from source.
Note, to use this feature on a machine with more than one controller,
steps like these are necessary:
# lspci | grep 1394
# ls /sys/bus/pci/drivers/firewire_ohci/
# echo -n "0000:03:02.0" > /sys/bus/pci/drivers/firewire_ohci/unbind
# echo 2 > /sys/module/firewire_ohci/parameters/quirks
# echo -n "0000:03:02.0" > /sys/bus/pci/drivers/firewire_ohci/bind
# echo 0 > /sys/module/firewire_ohci/parameters/quirks
The parameter can also be used to switch off quirk flags that were
hardwired into firewire-ohci's quirks table. Simply specify a non-zero
quirks value but without any known flags, e.g. 0x100.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
We don't have a lot of quirks to take into account (especially since
dual-buffer IR is out of the picture), but still, a table-based approach
is more organized than a series of if () clauses.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The config_rom struct members are only accessed during relatively
infrequent self-ID-complete interrupts and only if the local config ROM
was changed, while the ar_, at_, ir_, it_ members are used very
frequently during I/O. Hence move the config_rom members further down.
More importantly, make the huge self_id_buffer member the last one; this
is only accessed in self-ID-complete interrupts.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This code was no longer used since 2.6.33, "firewire: ohci: always use
packet-per-buffer mode for isochronous reception" commit 090699c0. If
anybody needs this code in the future for special purposes, it can be
brought back in. But it must not be re-enabled by default; drivers
(kernelspace or userspace drivers) should only get this mode if they
explicitly request it.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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>
ohci: Break out of the retry loop if too many attempts were necessary.
This may theoretically happen if the chip is fatally defective or if the
get_cycle_timer ioctl was performed after a CardBus controller was
ejected.
Also micro-optimize the loop by re-using the last two register reads in
the next iteration, remove a questionable inline keyword, and shuffle a
comment around.
core: ioctl_get_cycle_timer() is always called with interrupts on,
therefore local_irq_save() can be replaced by local_irq_disable().
Disabled local IRQs imply disabled preemption, hence preempt_disable()
can be removed.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Discussed in "read_cycle_timer backwards for sub-cycle 0000, 0001",
http://thread.gmane.org/gmane.linux.kernel.firewire.devel/13704
Known bad controllers:
ALi M5271, listed by lspci as M5253 [10b9:5253]
NEC OrangeLink [1033:00cd] (rev 03)
NEC uPD72874 [1033:00f2] (rev 01)
VIA VT6306 [1106:3044] (rev 46)
VIA VT6308P, listed by lspci as rev c0
Reported-by: Pieter Palmers <pieterp@joow.be>
Reported-by: Håkan Johansson <f96hajo@chalmers.se>
Reported-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
VIA controllers sometimes return an inconsistent value when reading the
isochronous cycle timer register. To work around this, read the
register multiple times and add consistency checks.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Reported-by: Pieter Palmers <pieterp@joow.be>
Reported-by: Håkan Johansson <f96hajo@chalmers.se>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
In isochronous transmit DMA descriptors, link the skip address pointer
back to the descriptor itself. When a cycle is lost, the controller
will send the packet in the next cycle, instead of terminating the
entire DMA program.
There are two reasons for this:
* This behaviour is compatible with the old IEEE1394 stack. Old
applications would not expect the DMA program to stop in this case.
* Since the OHCI driver does not report any uncompleted packets, the
context would stop silently; clients would not have any chance to
detect and handle this error without a watchdog timer.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Pieter Palmers notes:
"The reason I added this retry behavior to the old stack is because some
cards now and then fail to send a packet (e.g. the o2micro card in my
dell laptop). I couldn't figure out why exactly this happens, my best
guess is that the card cannot fetch the payload data on time. This
happens much more frequently when sending large packets, which leads me
to suspect that there are some contention issues with the DMA that fills
the transmit FIFO.
In the old stack it was a pretty critical issue as it resulted in a
freeze of the userspace application.
The omission of a packet doesn't necessarily have to be an issue. E.g.
in IEC61883 streams the DBC field can be used to detect discontinuities
in the stream. So as long as the other side doesn't bail when no
[packet] is present in a cycle, there is not really a problem.
I'm not convinced though that retrying is the proper solution, but it is
simple and effective for what it had to do. And I think there are no
reasons not to do it this way. Userspace can still detect this by
checking the cycle the descriptor was sent in."
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (changelog, comment)
Unsurprisingly, Texas Instruments TSB43AB23 exhibits the same behaviour
as TSB43AB22/A in dual buffer IR DMA mode: If descriptors are located
at physical addresses above the 31 bit address range (2 GB), the
controller will overwrite random memory. With luck, this merely
prevents video reception. With only a little less luck, the machine
crashes.
We use the same workaround here as with TSB43AB22/A: Switch off the
dual buffer capability flag and use packet-per-buffer IR DMA instead.
Another possible workaround would be to limit the coherent DMA mask to
31 bits.
In Linux 2.6.33, this change serves effectively only as documentation
since dual buffer mode is not used for any controller anymore. But
somebody might want to re-enable it in the future to make use of
features of dual buffer DMA that are not available in packet-per-buffer
mode.
In Linux 2.6.32 and older, this update is vital for anyone with this
controller, more than 2 GB RAM, a 64 bit kernel, and FireWire video or
audio applications.
We have at least four reports:
http://bugzilla.kernel.org/show_bug.cgi?id=13808http://marc.info/?l=linux1394-user&m=126154279004083https://bugzilla.redhat.com/show_bug.cgi?id=552142http://marc.info/?l=linux1394-user&m=126432246128386
Reported-by: Paul Johnson
Reported-by: Ronneil Camara
Reported-by: G Zornetzer
Reported-by: Mark Thompson
Cc: stable@kernel.org
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The id_table field of the struct pci_driver is constant in <linux/pci.h>
so it is worth to make pci_table also constant. Found with Coccinelle.
Signed-off-by: Márton Németh <nm127@freemail.hu>
Cc: Julia Lawall <julia@diku.dk>
Cc: cocci@diku.dk
Signed-off-by: Stefan Richter stefanr@s5r6.in-berlin.de> (changelog)
This is a minimal change meant for the short term: Never set the
ohci->use_dualbuffer flag to true.
There are two reasons to do so:
- Packet-per-buffer mode and dual-buffer mode do not behave the same
under certain circumstances, notably if several packets are covered
by a single fw_cdev_iso_packet descriptor.
http://marc.info/?l=linux1394-devel&m=124965653718313
Therefore the driver stack should not silently choose one or the
other mode but should leave the choice to the high-level driver
(regardless if kernel driver or userspace driver). Or simply always
only offer packet-per-buffer mode, since a considerable number of
controllers, even current ones, does not offer dual-buffer support.
- Even under circumstances where packet-per-buffer mode and
dual-buffer mode behave exactly the same --- notably when used
through libraw1394, libdc1394, as well as the current two kernel
drivers which use isochronous reception (firewire-net and firedtv)
--- we are still faced with the problem that several OHCI 1.1
controllers have bugs in dual-buffer mode. Although it looks like
we have identified most of those buggy controllers by now, we
cannot be quite sure about that.
So, use packet-per-buffer by default from now on. This change should
be followed up by a more complete solution: Either extend the
in-kernel API and the userspace ABI by a choice between the two IR modes
or remove all dual-buffer related code from firewire-ohci.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Queueing to receive an ISO packet with a payload length of zero
silently does nothing in dualbuffer mode, and crashes the kernel in
packet-per-buffer mode. Return an error in dualbuffer mode, because
the DMA controller won't let us do what we want, and work correctly in
packet-per-buffer mode.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: stable@kernel.org
Here is the final set of patches I used to get ffado to work with the
new firewire stack. With these patches, I was able to start ardour
and record from and playback to my PreSonus Inspire1394 from a
(mostly) Fedora 12 system.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Until now, firewire-ohci exposed only the transmit cycle of the last
transmitted packet at each isochronous transmit complete event. This
made it impossible for FFADO (FireWire audio drivers in userspace) to
synchronize audio-out streams. The fix is to store the timestamp of
each packet in the iso xmit event. As a bonus, the transfer status is
stored too.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Calling the START_ISO ioctl with a nonnegative cycle paramater has
never worked. Last night I got around to figuring out why. Most of
this patch is a big comment explaining why we enable an interrupt
source then don't actually do anything when we get one. As the
comment says, we should do more, but we don't have a way to tell
userspace what happened. . .
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (edited comment)
I was told that there are obscure architectures with non-coherent DMA
which may DMA-map to bus address 0. We shall not use 0 as a magic
number of uninitialized bus address variables.
The packet->payload_length > 0 test cannot be used either (except in
at_context_queue_packet) because local requests are not DMA-mapped
regardless of payload_length. Hence add a state flag to struct
fw_packet.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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>
The selfIDSize field of Self ID Count is 9 bits wide, and we are only
interested in the high 8 bits. Fix the mask accordingly. The
previously too large mask didn't do damage though because the next few
bits in the register are reserved and therefore zero with presently
existing hardware.
Also, check for the maximum possible self ID count of 252 (according to
OHCI 1.1 clause 11.2 and IEEE 1394a-2000 clause 4.3.4.1, i.e. up to four
self IDs of up to 63 nodes, even though IEEE 1394 up to edition 2008
defines only up to three self IDs per node). More than 252 self IDs
would only happen if the self ID receive DMA unit malfunctioned, which
would likely be caught by other self ID buffer checks. However, check
it early to be sure. More than 253 quadlets would overflow the Topology
Map CSR.
Reported-By: PaX Team
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
In dual-buffer DMA mode, no video frames are ever received from R5C832
by libdc1394. Fallback to packet-per-buffer DMA works reliably.
http://thread.gmane.org/gmane.linux.kernel.firewire.devel/13393/focus=13476
Reported-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
An Agere FW643 OHCI 1.1 card works fine for video reception from one
camera but fails early if receiving from two cameras. After a short
while, no IR IRQ events occur and the context control register does not
react anymore. This happens regardless whether both IR DMA contexts are
dual-buffer or one is dual-buffer and the other packet-per-buffer.
This can be worked around by disabling dual buffer DMA mode entirely.
http://sourceforge.net/mailarchive/message.php?msg_name=4A7C0594.2020208%40gmail.com
(Reported by Samuel Audet.)
In another report (by Jonathan Cameron), an FW643 works OK with two
cameras in dual buffer mode. Whether this is due to different chip
revisions or different usage patterns (different video formats) is not
yet clear. However, as far as the current capabilities of
firewire-core's isochronous I/O interface are concerned, simply
switching off dual-buffer on non-working and working FW643s alike is not
a problem in practice. We only need to revisit this issue if we are
going to enhance the interface, e.g. so that applications can explicitly
choose modes.
Reported-by: Samuel Audet <samuel.audet@gmail.com>
Reported-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The source files of firewire-core, firewire-ohci, firewire-sbp2, i.e.
"drivers/firewire/fw-*.c"
are renamed to
"drivers/firewire/core-*.c",
"drivers/firewire/ohci.c",
"drivers/firewire/sbp2.c".
The old fw- prefix was redundant to the directory name. The new core-
prefix distinguishes the files according to which driver they belong to.
This change comes a little late, but still before further firewire
drivers are added as anticipated RSN.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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>
Include required headers which were only indirectly included.
Remove unused includes and an unused constant.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
In the unlikely event that card->driver->get_bus_time() is called during
a cycle64Seconds interrupt, we could read garbage unless atomic accesses
are used.
The switch to atomic ops requires to change the 64 seconds counter from
unsigned to signed, but this shouldn't matter to the end result.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Allow userspace and other firewire drivers (fw-ipv4 I'm looking at
you!) to send Asynchronous Transmit Streams as described in 7.8.3 of
release 1.1 of the 1394 Open Host Controller Interface Specification.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (tweaks)
Standardize on if (err)
handle_error;
and if (ret < 0)
handle_error;
Don't call a variable err if we store values in it which mean success.
Also, offset some return statements by a blank line since this how we do
it in drivers/firewire.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
OHCI-1394 1.1 clause 10.4.3 says: "If more than one IR DMA context
specifies receives for packets from the same isochronous channel, the
context destination for that channel's packets is undefined."
Any userspace client and in the future also kernelspace clients can
allocate IR DMA contexts for any channel. We don't want them to
interfere with each other, hence it is preferable to return -EBUSY if
allocation of a second context for a channel is attempted.
Notes:
- This limitation is OHCI-1394 specific, therefore its proper place of
implementation is down in the low-level driver.
- Since the <linux/firewire-cdev.h> ABI simply maps one userspace iso
client context to one hardware iso context, this OHCI-1394
limitation alas requires userspace to implement its own multiplexing
of iso reception from the same channel and card to multiple clients
when needed.
- The limitation is independent of channel allocation at the IRM; the
latter is really only important for the initiation of iso
transmission but not of iso reception.
- We don't need to do the same for IT DMA because OHCI-1394 does not
have any ties between IT contexts and channels. Only the voluntary
channel allocation protocol via the IRM, globally to the FireWire
bus, can ensure proper isochronous transmit behaviour anyway.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Previously, when an iso context had header_size > 4, the iso header
(len/tag/channel/tcode/sy) was passed to userspace followed by quadlets
stripped from the payload. This patch changes the behavior:
header_size = 8 now passes the header quadlet followed by the timestamp
quadlet. When header_size > 8, quadlets are stripped from the payload.
The header_size = 4 case remains identical.
Since this alters the semantics of the API, the firewire API version
needs to be bumped concurrently with this change.
This change also refactors the header copying code slightly to be much
easier to read.
Signed-off-by: David Moore <dcm@acm.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Camcorders have a tendency to fail read requests to their config ROM and
write request to their FCP command register with ack_busy_X. This has
become a problem with newer kernels and especially Panasonic camcorders,
causing AV/C in dvgrab and kino to fail. Dvgrab for example frequently
logs "send oops"; kino reports loss of AV/C control. I suspect that
lower CPU scheduling latencies in newer kernels made this issue more
prominent now.
According to
https://sourceforge.net/tracker/?func=detail&atid=114103&aid=2492640&group_id=14103
this can be fixed by configuring the FireWire controller for more
hardware retries for request transmission; these retries are evidently
more successful than libavc1394's own retry loop (typically 3 tries on
top of hardware retries).
Presumably the same issue has been reported at
https://bugzilla.redhat.com/show_bug.cgi?id=449252 and
https://bugzilla.redhat.com/show_bug.cgi?id=477279 .
In a quick test with a JVC camcorder (which didn't malfunction like the
reported camcorders), this change decreased the number of ack_busy_X
from 16 in three runs of dvgrab to 4 in three runs of the same capture
duration.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The present message is mostly just noise. We only need to be notified
if the "active" flag does not go off before the retry loop terminates.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
There is a DMA map/ unmap imbalance whenever a block write request
packet is sent and then dequeued with ohci_cancel_packet. The latter
may happen frequently if the AR resp tasklet is executed before the AT
req tasklet for the same transaction.
Add the missing dma_unmap_single. This fixes
https://bugzilla.redhat.com/show_bug.cgi?id=475156
Reported-by: Emmanuel Kowalski
Tested-by: Emmanuel Kowalski
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The transmit and receive context dma memory was not being freed on
module removal. Neither was the config rom memory. Fix that.
The ab->next assignment is pure paranoia.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Add per-device dma_mapping_ops support for CONFIG_X86_64 as POWER
architecture does:
This enables us to cleanly fix the Calgary IOMMU issue that some devices
are not behind the IOMMU (http://lkml.org/lkml/2008/5/8/423).
I think that per-device dma_mapping_ops support would be also helpful for
KVM people to support PCI passthrough but Andi thinks that this makes it
difficult to support the PCI passthrough (see the above thread). So I
CC'ed this to KVM camp. Comments are appreciated.
A pointer to dma_mapping_ops to struct dev_archdata is added. If the
pointer is non NULL, DMA operations in asm/dma-mapping.h use it. If it's
NULL, the system-wide dma_ops pointer is used as before.
If it's useful for KVM people, I plan to implement a mechanism to register
a hook called when a new pci (or dma capable) device is created (it works
with hot plugging). It enables IOMMUs to set up an appropriate
dma_mapping_ops per device.
The major obstacle is that dma_mapping_error doesn't take a pointer to the
device unlike other DMA operations. So x86 can't have dma_mapping_ops per
device. Note all the POWER IOMMUs use the same dma_mapping_error function
so this is not a problem for POWER but x86 IOMMUs use different
dma_mapping_error functions.
The first patch adds the device argument to dma_mapping_error. The patch
is trivial but large since it touches lots of drivers and dma-mapping.h in
all the architecture.
This patch:
dma_mapping_error() doesn't take a pointer to the device unlike other DMA
operations. So we can't have dma_mapping_ops per device.
Note that POWER already has dma_mapping_ops per device but all the POWER
IOMMUs use the same dma_mapping_error function. x86 IOMMUs use device
argument.
[akpm@linux-foundation.org: fix sge]
[akpm@linux-foundation.org: fix svc_rdma]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix bnx2x]
[akpm@linux-foundation.org: fix s2io]
[akpm@linux-foundation.org: fix pasemi_mac]
[akpm@linux-foundation.org: fix sdhci]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix sparc]
[akpm@linux-foundation.org: fix ibmvscsi]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clemens Ladisch