Freeing an AR buffer page just to allocate a new page immediately
afterwards is not only a pointless effort but also dangerous because
the allocation can fail, which would result in an oops later.
Split ar_context_add_page() into two functions so that we can reuse
the old page directly.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
When handling an AR buffer that has been completely filled, we assumed
that its descriptor will not be read by the controller and can be
overwritten. However, when the last received packet happens to end at
the end of the buffer, the controller might not yet have moved on to the
next buffer and might read the branch address later. If we overwrite
and free the page before that, the DMA context will either go dead
because of an invalid Z value, or go off into some random memory.
To fix this, ensure that the descriptor does not get overwritten by
using only the actual buffer instead of the entire page for reassembling
the split packet. Furthermore, to avoid freeing the page too early,
move on to the next buffer only when some data in it guarantees that the
controller has moved on.
This should eliminate the remaining firewire-net problems.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: 2.6.22-2.6.36 <stable@kernel.org>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
When the controller had to split a received asynchronous packet into two
buffers, the driver tries to reassemble it by copying both parts into
the first page. However, if size + rest > PAGE_SIZE, i.e., if the yet
unhandled packets before the split packet, the split packet itself, and
any received packets after the split packet are together larger than one
page, then the memory after the first page would get overwritten.
To fix this, do not try to copy the data of all unhandled packets at
once, but copy the possibly needed data every time when handling
a packet.
This gets rid of most of the infamous crashes and data corruptions when
using firewire-net.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: 2.6.22-2.6.36 <stable@kernel.org>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (cast PAGE_SIZE to size_t)
Revert commit 54672386cc
"firewire: ohci: fix up configuration of TI chips".
It caused massive slow-down and data corruption with a TSB82AA2 based
StarTech EC1394B2 ExpressCard and FireWire 800 harddisks.
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/657081http://thread.gmane.org/gmane.linux.kernel.firewire.user/4013
The fact that some card EEPROMs do not program these enhancements may be
related to TSB81BA3 phy chip errata, if not to bugs of TSB82AA2 itself.
We could re-add these configuration steps, but only conditional on a
whitelist of cards on which these enhancements bring a proven positive
effect.
Reported-and-tested-by: Eric Shattow <lucent@gmail.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: <stable@kernel.org> 2.6.35
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The Ricoh FireWire controllers appear to have the non-atomic cycle
timer register access bug, so, activate the driver workaround by
default.
The behaviour was observed on:
Ricoh Co Ltd R5C552 IEEE 1394 Controller [1180:0552] and
Ricoh Co Ltd R5C832 IEEE 1394 Controller [1180:0832] (rev 04).
Signed-off-by: Heikki Lindholm <holin@iki.fi>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
VIA VT6306, VIA VT6308, and NEC OrangeLink controllers do not write
packet event codes for received PHY packets (or perhaps write
evt_no_status, hard to tell). Work around it by overwriting the
packet's ACK by ack_complete, so that upper layers that listen to PHY
packet reception get to see these packets.
(Also tested: TI TSB82AA2, TI TSB43AB22/A, TI XIO2213A, Agere FW643,
JMicron JMB381 --- these do not exhibit this bug.)
Clemens proposed a quirks flag for that, IOW whitelist known misbehaving
controllers for this workaround. Though to me it seems harmless enough
to enable for all controllers.
The log_ar_at_event() debug log will continue to show the original
status from the DMA unit.
Reported-by: Clemens Ladisch <clemens@ladisch.de> (VT6308)
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Conflicts:
drivers/firewire/core-card.c
drivers/firewire/core-cdev.c
and forgotten #include <linux/time.h> in drivers/firewire/ohci.c
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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>
firewire-ohci keeps book of which isochronous channels are occupied by
IR DMA contexts, so that there cannot be more than one context listening
to a certain channel.
If IR context creation failed due to an out-of-memory condition, this
bookkeeping leaked a channel.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
When we append to a DMA program, we need to ensure that the order in
which initialization of the new descriptors and update of the
branch_address of the old tail descriptor, as seen by the PCI device,
happen as intended.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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>
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>
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>
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>
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>
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>
Add a comment on which of the conflicting NODE_IDS specifications we
implement. Reduce a comment on rather irrelevant register bits that can
all be looked up in the spec (or from now on in the code history).
Directly include the required indirectly included bug.h.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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>
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>
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>
Implement the BUS_TIME register, which is required for cycle master
capable nodes and tested for by the Base 1393 Test Suite. Even when
there is not yet bus master initialization support, this register allows
us to work together with other bus masters.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
The specification requires that CYCLE_TIME is writable so that it can be
initialized, so we better implement it.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
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>
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>
Most PHY chips, when idle, can complete a register access in the time
needed for two or three PCI read transactions; bigger delays occur only
when data is currently being moved over the link/PHY interface. So if
we busy-wait a few times when waiting for the register access to finish,
it is likely that we can finish without having to sleep.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
This patch adds support for message-signaled interrupts.
Any native PCI-Express OHCI controller should support MSI, but most are
just PCI cores behind a PCI-E/PCI bridge. The only chips that are known
to claim to support MSI are the Lucent/Agere/LSI FW643 and the VIA
VT6315, none of which I have been able to test.
Due to the high level of trust I have in the competence of these and any
future chip makers, I thought it a good idea to add a disable-MSI quirk.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Tested Agere FW643 rev 07 [11c1:5901] and JMicron JMB381 [197b:2380].
Added a quirks list entry for JMB38X since it kept its count of MSI
events consistently at zero.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
On 26 Apr 2010, Clemens Ladisch wrote:
> In theory, none of the interrupts should occur before the link is
> enabled. In practice, I'd rather make sure to not set the master
> interrupt enable bit until we have installed the interrupt handler.
and proposed to move OHCI1394_masterIntEnable out of the present
reg_write() into a new one before the HCControl.linkEnable reg_write().
Why not defer setting /all/ of the bits until right before linkEnable?
Reviewed-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
ieee1394: schedule for removal
firewire: core: use separate timeout for each transaction
firewire: core: Fix tlabel exhaustion problem
firewire: core: make transaction label allocation more robust
firewire: core: clean up config ROM related defined constants
ieee1394: mark char device files as not seekable
firewire: cdev: mark char device files as not seekable
firewire: ohci: cleanups and fix for nonstandard build without debug facility
firewire: ohci: wait for PHY register accesses to complete
firewire: ohci: fix up configuration of TI chips
firewire: ohci: enable 1394a enhancements
firewire: ohci: do not clear PHY interrupt status inadvertently
firewire: ohci: add a function for reading PHY registers
Trivial conflicts in Documentation/feature-removal-schedule.txt
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (44 commits)
vlynq: make whole Kconfig-menu dependant on architecture
add descriptive comment for TIF_MEMDIE task flag declaration.
EEPROM: max6875: Header file cleanup
EEPROM: 93cx6: Header file cleanup
EEPROM: Header file cleanup
agp: use NULL instead of 0 when pointer is needed
rtc-v3020: make bitfield unsigned
PCI: make bitfield unsigned
jbd2: use NULL instead of 0 when pointer is needed
cciss: fix shadows sparse warning
doc: inode uses a mutex instead of a semaphore.
uml: i386: Avoid redefinition of NR_syscalls
fix "seperate" typos in comments
cocbalt_lcdfb: correct sections
doc: Change urls for sparse
Powerpc: wii: Fix typo in comment
i2o: cleanup some exit paths
Documentation/: it's -> its where appropriate
UML: Fix compiler warning due to missing task_struct declaration
UML: add kernel.h include to signal.c
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
firewire: ohci: wait for local CSR lock access to finish
firewire: ohci: prevent aliasing of locally handled register addresses
firewire: core: fw_iso_resource_manage: return -EBUSY when out of resources
firewire: core: fix retries calculation in iso manage_channel()
firewire: cdev: fix cut+paste mistake in disclaimer
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>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
firewire: ohci: handle receive packets with a data length of zero
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>
Clemens Ladisch