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path: root/drivers/firewire/ohci.c
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2013-01-29Merge branch 'master' into for-nextJiri Kosina
Conflicts: drivers/devfreq/exynos4_bus.c Sync with Linus' tree to be able to apply patches that are against newer code (mvneta).
2013-01-09treewide: Fix typo in various driversMasanari Iida
Correct spelling typo in printk within various drivers. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-12-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial branch from Jiri Kosina: "Usual stuff -- comment/printk typo fixes, documentation updates, dead code elimination." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits) HOWTO: fix double words typo x86 mtrr: fix comment typo in mtrr_bp_init propagate name change to comments in kernel source doc: Update the name of profiling based on sysfs treewide: Fix typos in various drivers treewide: Fix typos in various Kconfig wireless: mwifiex: Fix typo in wireless/mwifiex driver messages: i2o: Fix typo in messages/i2o scripts/kernel-doc: check that non-void fcts describe their return value Kernel-doc: Convention: Use a "Return" section to describe return values radeon: Fix typo and copy/paste error in comments doc: Remove unnecessary declarations from Documentation/accounting/getdelays.c various: Fix spelling of "asynchronous" in comments. Fix misspellings of "whether" in comments. eisa: Fix spelling of "asynchronous". various: Fix spelling of "registered" in comments. doc: fix quite a few typos within Documentation target: iscsi: fix comment typos in target/iscsi drivers treewide: fix typo of "suport" in various comments and Kconfig treewide: fix typo of "suppport" in various comments ...
2012-11-28firewire: remove use of __devinitBill Pemberton
CONFIG_HOTPLUG is going away as an option so __devinit is no longer needed. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-19various: Fix spelling of "asynchronous" in comments.Adam Buchbinder
"Asynchronous" is misspelled in some comments. No code changes. Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-09-25firewire: ohci: get IR bit from TSB41BA3D phyStephan Gatzka
In case of a self constructed selfID packet this patch correctly determines the information if the TSB41BA3D phy initiated a bus reset. Signed-off-by: Stephan Gatzka <stephan.gatzka@gmail.com> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-06-17firewire: ohci: initialize multiChanMode bits after resetClemens Ladisch
OHCI 1.1 says: | Since the value of this bit is undefined after reset in all IR | contexts, software shall initialize this bit to zero in all contexts | whether or not active to maintain the exclusive nature of this bit. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-06-04firewire: ohci: sanity-check MMIO resourceClemens Ladisch
pci_request_region() does not fail on resources that have not been allocated by the BIOS or by the kernel, so to avoid accessing registers that are not there, we have to check for this explicitly. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-05-27firewire: ohci: lazy bus time initializationClemens Ladisch
The Bus_Time CSR is virtually never used, so we can avoid burning CPU in interrupt context for 1 or 3 IsochronousCycleTimer accesses every minute by not tracking the bus time until the CSR is actually accessed for the first time. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-04-17firewire: ohci: omit spinlock IRQ flags where possibleStefan Richter
bus_reset_work() is only called from workqueue thread context. ohci_set_config_rom() and ohci_allocate_iso_context() perform GFP_KERNEL memory allocations, therefore they must be called with interrupts enabled. Hence these functions may disable and enable local IRQs without having to track IRQ state. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-04-17firewire: ohci: correct signedness of a local variableStefan Richter
bus_reset_work's reg is a bitfield. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-04-09firewire: use module_pci_driverAxel Lin
This patch converts the drivers in drivers/firewire/* to use module_pci_driver() macro which makes the code smaller and a bit simpler. Signed-off-by: Axel Lin <axel.lin@gmail.com> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-03-28Remove all #inclusions of asm/system.hDavid Howells
Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
2012-03-23Merge tag 'firewire-updates' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394 Pull IEEE 1394 (FireWire) subsystem updates post v3.3 from Stefan Richter: - Some SBP-2 initiator fixes, side product from ongoing work on a target. - Reintroduction of an isochronous I/O feature of the older ieee1394 driver stack (flush buffer completions); it was evidently rarely used but not actually unused. Matching libraw1394 code is already available. - Be sure to prefix all kernel log messages with device name or card name, and other logging related cleanups. - Misc other small cleanups, among them a small API change that affects sound/firewire/ too. Clemens Ladisch is aware of it. * tag 'firewire-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394: (26 commits) firewire: allow explicit flushing of iso packet completions firewire: prevent dropping of completed iso packet header data firewire: ohci: factor out iso completion flushing code firewire: ohci: simplify iso header pointer arithmetic firewire: ohci: optimize control bit checks firewire: ohci: remove unused excess_bytes field firewire: ohci: copy_iso_headers(): make comment match the code firewire: cdev: fix IR multichannel event documentation firewire: ohci: fix too-early completion of IR multichannel buffers firewire: ohci: move runtime debug facility out of #ifdef firewire: tone down some diagnostic log messages firewire: sbp2: replace a GFP_ATOMIC allocation firewire: sbp2: Fix SCSI sense data mangling firewire: sbp2: Ignore SBP-2 targets on the local node firewire: sbp2: Take into account Unit_Unique_ID firewire: nosy: Use the macro DMA_BIT_MASK(). firewire: core: convert AR-req handler lock from _irqsave to _bh firewire: core: fix race at address_handler unregistration firewire: core: remove obsolete comment firewire: core: prefix log messages with card name ...
2012-03-18firewire: allow explicit flushing of iso packet completionsClemens Ladisch
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>
2012-03-18firewire: prevent dropping of completed iso packet header dataClemens Ladisch
The buffer for the header data of completed iso packets has a fixed size, so it is possible to configure a stream with a big interval between interrupt packets or with big headers so that this buffer would overflow. Previously, ohci.c would drop any data that would not fit, but this could make unsuspecting applications believe that fewer than the actual number of packets have completed. Instead of dropping data, add calls to flush_iso_completion() so that there are as many events as needed to report all of the data. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-03-18firewire: ohci: factor out iso completion flushing codeClemens Ladisch
In preparation for the following patches that add more flushing, move the code for flushing accumulated header data into a common function. The timestamp of the last completed packed is passed through the context structure instead of a function parameter to allow accessing this value later outside of the handle_i?_packet functions. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-03-18firewire: ohci: simplify iso header pointer arithmeticClemens Ladisch
When storing the header data of completed iso packets, we effectively treat the buffers as arrays of quadlets. Actually declaring the pointers as u32* avoids repetitive pointer arithmetic, removes the unhelpfully named "i" variables, and thus makes the code clearer. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-03-18firewire: ohci: optimize control bit checksClemens Ladisch
Doing the endian conversion on the constant instead of the memory field allows the compiler to do the conversion at compile time. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-03-18firewire: ohci: remove unused excess_bytes fieldClemens Ladisch
Commit 6498ba04aee6 (remove unused dualbuffer IR code) overlooked a field in struct iso_context. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-03-18firewire: ohci: copy_iso_headers(): make comment match the codeClemens Ladisch
The comment incorrectly talked about one little-endian quadlet, while there are actually two. Furthermore, the endianness of the remaining headers depends on whatever protocol is used, so don't mention them. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-03-17firewire: ohci: fix too-early completion of IR multichannel buffersClemens Ladisch
handle_ir_buffer_fill() assumed that a completed descriptor would be indicated by a non-zero transfer_status (as in most other descriptors). However, this field is written by the controller as soon as (the end of) the first packet has been written into the buffer. As a consequence, if we happen to run into such a descriptor when the interrupt handler is executed after such a packet has completed, the descriptor would be taken out of the list of active descriptors as soon as the buffer had been partially filled, so the event for the buffer being completely filled would never be sent. To fix this, handle descriptors only when they have been completely filled, i.e., when res_count == 0. (This also matches the condition that is reported by the controller with an interrupt.) Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Cc: 2.6.36+ <stable@vger.kernel.org> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-03-10firewire: ohci: move runtime debug facility out of #ifdefStefan Richter
CONFIG_FIREWIRE_OHCI_DEBUG could have been exposed to kernel tweakers if CONFIG_EXPERT was set. But in hindsight, this stuff is far too useful to omit it. So get rid of two #else branches that are only going to bitrot otherwise. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-03-10firewire: tone down some diagnostic log messagesStefan Richter
The "skipped bus generations" message was added together with the respective fw_device retaining/ reviving code in order to see how it all works out. It did well, so don't spam the log anymore. The "register access failure" situation still needs an actual handler. But at this point it makes less sense to ask folks to send mails about it. We now have a pretty good picture of what controllers emit this and when: Texas Instruments PCIxx21 FireWire + CardBus + flash memory card controller: https://bugzilla.redhat.com/show_bug.cgi?id=608544 O2 Micro FireWire + flash memory card controller: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/801719 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/881688 http://marc.info/?l=linux1394-devel&m=132309283531423 http://marc.info/?l=linux1394-devel&m=132368567907469 http://marc.info/?l=linux1394-devel&m=132516165727468 http://marc.info/?l=linux1394-devel&m=133006486927699 Pinnacle Movieboard: commit 7f7e37115a8b6724f26d0637a04e1d35e3c59717 http://marc.info/?l=linux1394-devel&m=130714243325962 Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-01-30firewire: ohci: disable MSI on Ricoh controllersStefan Richter
The PCIe device FireWire (IEEE 1394) [0c00]: Ricoh Co Ltd FireWire Host Controller [1180:e832] (prog-if 10 [OHCI]) is unable to access attached FireWire devices when MSI is enabled but works if MSI is disabled. http://www.mail-archive.com/alsa-user@lists.sourceforge.net/msg28251.html Hence add the "disable MSI" quirks flag for this device, or in fact for safety and simplicity for all current (R5U230, R5U231, R5U240) and future Ricoh PCIe 1394 controllers. Reported-by: Stefan Thomas <kontrapunktstefan@googlemail.com> Cc: 2.6.36+ <stable@vger.kernel.org> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-01-26firewire: ohci: add reset packet quirk for SB AudigyClemens Ladisch
The Audigy's SB1394 controller is actually from Texas Instruments and has the same bus reset packet generation bug, so it needs the same quirk entry. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Cc: 2.6.36+ <stable@vger.kernel.org> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2012-01-15firewire: ohci: use dev_printk APIStefan Richter
All messages are uniformly prefixed by driver name and device name now. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-10-18firewire: ohci: fix isochronous DMA synchronizationClemens Ladisch
Add the dma_sync_single_* calls necessary to ensure proper cache synchronization for isochronous data buffers on non-coherent architectures. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-10-18firewire: ohci: work around selfID junk due to wrong gap countClemens Ladisch
If a device's firmware initiates a bus reset by setting the IBR bit in PHY register 1 without resetting the gap count field to 63 (and without having sent a PHY configuration packet beforehand), the gap count of this node will remain at the old value after the bus reset and thus be inconsistent with the gap count on all other nodes. The bus manager is supposed to detect the inconsistent gap count values in the self ID packets and correct them by issuing another bus reset. However, if the buggy device happens to be the cycle master, and if it sends a cycle start packet immediately after the bus reset (which is likely after a long bus reset), then the time between the end of the selfID phase and the start of the cycle start packet will be based on the too-small gap count value, so this gap will be too short to be detected as a subaction gap by the other nodes. This means that the cycle start packet will be assumed to be self ID data, and will be stored after the actual self ID quadlets in the self ID buffer. This garbage in the self ID buffer made firewire-core ignore all of the self ID data, and thus prevented the Linux bus manager from correcting the problem. Furthermore, because the bus reset handling was aborted completely, asynchronous transfers would be no longer handled correctly, and fw_run_transaction() would hang until the next bus reset. To fix this, make the detection of inconsistent self IDs more discriminating: If the invalid data in the self ID buffer looks like a cycle start packet, we can assume that the previous data in the buffer is correctly received self ID information, and process it normally. (We inspect only the first quadlet of the cycle start packet, because this value is different enough from any valid self ID quadlet, and many controllers do not store the cycle start packet in five quadlets because they expect self ID data to have an even number of quadlets.) This bug has been observed when a bus-powered DesktopKonnekt6 is switched off with its power button. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-10-09firewire: net: Use posted writesStephan Gatzka
Change memory region to ohci "middle address space". This effectively reduces the number of packets by 50%. [Stefan R.:] This eliminates 1394 ack packets and improved throughput by a few percent in some tests with an S400a connection with and without gap count optimization. Since firewire-net taxes the AR-req DMA unit of a FireWire controller much more than firewire-sbp2 (which uses the middle address space with PCI posted writes too), this commit also changes a related error printk into a ratelimited one as a precaution. Side note: The IPv4-over-1394 drivers of Mac OS X 10.4, Windows XP SP3, and the Thesycon 1394 bus driver for Windows all use the middle address space too. Signed-off-by: Stephan Gatzka <stephan@gatzka.org> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-10-09firewire: ohci: optimize TSB41BA3D detectionStefan Richter
Takes less source code and machine code, and less runtime with PHYs other than TSB41BA3D (e.g. TSB81BA3 with device ID 0x831304 which takes one instead of six read_paged_phy_reg now). Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-10-09firewire: ohci: TSB41BA3D support tweaksStefan Richter
Fix: phy_reg_mutex must be held over the write/read_phy_reg pair which gets PHY port status. Only print to the log when a TSB41BA3D was found. By far most TSB82AA2 cards have a TSB81BA3, and firewire-ohci can keep quiet about that. Shorten some strings and comments. Change some whitespace. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-09-16firewire: ohci: Add support for TSB41BA3D phyStephan Gatzka
This patch implements a work around for the Texas Instruments PHY TSB41BA3D. This phy has a bug at least in combination with the TI LLCs TSB82AA2B and TSB12LV26. The selfid coming from the locally connected phy is not propagated into the selfid buffer of the OHCI (see http://www.ti.com/litv/pdf/sllz059 for details). The main idea is to construct the selfid ourselves. Signed-off-by: Stephan Gatzka <stephan@gatzka.org> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-09-16firewire: ohci: Move code from the bus reset tasklet into a workqueueStephan Gatzka
Code inside bus_reset_work may now sleep. This is a prerequisite to support a phy from Texas Instruments cleanly. The patch to support this phy will be submitted later. Signed-off-by: Stephan Gatzka <stephan@gatzka.org> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-09-16firewire: ohci: add no MSI quirk for O2Micro controllerMing Lei
This fixes https://bugs.launchpad.net/ubuntu/+source/linux/+bug/801719 . An O2Micro PCI Express FireWire controller, "FireWire (IEEE 1394) [0c00]: O2 Micro, Inc. Device [1217:11f7] (rev 05)" which is a combination device together with an SDHCI controller and some sort of storage controller, misses SBP-2 status writes from an attached FireWire HDD. This problem goes away if MSI is disabled for this FireWire controller. The device reportedly does not require QUIRK_CYCLE_TIMER. Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (amended changelog) Cc: <stable@kernel.org>
2011-08-15Merge branch 'fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6: firewire: ohci: fix DMA unmapping in an error path firewire: cdev: fix 32 bit userland on 64 bit kernel compat corner cases
2011-08-12firewire: ohci: fix DMA unmapping in an error pathStefan Richter
If request_irq failed, we would pass wrong arguments to dma_free_coherent. https://bugzilla.redhat.com/show_bug.cgi?id=728185 Reported-by: Mads Kiilerich Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-22Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6: firewire: document the sysfs ABIs firewire: cdev: ABI documentation enhancements firewire: cdev: prevent race between first get_info ioctl and bus reset event queuing firewire: cdev: return -ENOTTY for unimplemented ioctls, not -EINVAL firewire: ohci: skip soft reset retries after card ejection firewire: ohci: fix PHY reg access after card ejection firewire: ohci: add a comment on PHY reg access serialization firewire: ohci: reduce potential context_stop latency firewire: ohci: remove superfluous posted write flushes firewire: net: replacing deprecated __attribute__((packed)) with __packed
2011-07-10firewire: ohci: do not bind to Pinnacle cards, avert panicStefan Richter
When firewire-ohci is bound to a Pinnacle MovieBoard, eventually a "Register access failure" is logged and an interrupt storm or a kernel panic happens. https://bugzilla.kernel.org/show_bug.cgi?id=36622 Until this is sorted out (if that is going to succeed at all), let's just prevent firewire-ohci from touching these devices. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: <stable@kernel.org>
2011-07-09firewire: ohci: skip soft reset retries after card ejectionStefan Richter
The software reset in firewire-ohci's pci_remove does not have a great prospect of success if the card was already physically removed at this point. So let's skip the 500 ms that were spent in retries here. Also, replace a defined constant by its open-coded value. This is not a constant from a specification but an arbitrarily chosen retry limit. It was only used in this single place. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09firewire: ohci: fix PHY reg access after card ejectionStefan Richter
Detect and handle ejection of FireWire CardBus cards in PHY register accesses: - The last attempt of firewire-core to reset the bus during shutdown caused a spurious "firewire_ohci: failed to write phy reg" error message in the log. Skip this message as well as the prior retry loop that needlessly took 100 milliseconds. - In the unlikely case that a PHY register was read right after card ejection, a bogus value was obtained and possibly acted upon. Instead, fail the read attempt. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09firewire: ohci: add a comment on PHY reg access serializationStefan Richter
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09firewire: ohci: reduce potential context_stop latencyStefan Richter
Stopping an isochronous reception DMA context takes two loop iterations in context_stop on several controllers (JMicron, NEC, VIA). But there is no extra delay necessary between these two reg_read trials; the MMIO reads themselves are slow enough. Hence bring back the behavior from before commit dd6254e5c0efe01ad255188898cb3dadf98cb56d "firewire: ohci: remove superfluous posted write flushes" on these controllers by means of an "if (i)" condition. Isochronous context stop is performed in preemptible contexts (and only rarely), hence this change is of little impact. (Besides, Agere and TI controllers always, or almost always, have the context stopped already at the first ContextControl read.) More important is asynchronous transmit context stop, which is performed while local interrupts are disabled (on the two AT DMAs in bus_reset_tasklet, i.e. after a self-ID-complete event). In my experience with several controllers, tested with a usermode AT-request transmitter as well as with FTP transmission over firewire-net, the AT contexts were luckily already stopped at the first ContextControl read, i.e. never required another MMIO read let alone mdelay. A possible explanation for this is that the controllers which I tested perhaps stop AT DMA before they perform the self-ID reception DMA. But we cannot be sure about that and should keep the interrupts-disabled busy loop as short as possible. Hence, query the ContextControl register in 1000 udelay(10) intervals instead of 10 udelay(1000) intervals. I understand from an estimation by Clemens Ladisch that stopping a busy DMA context should take microseconds or at worst tens of microseconds, not milliseconds. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-06-02firewire: ohci: remove superfluous posted write flushesClemens Ladisch
The call to flush_writes() in context_stop() is superfluous because another register read is done immediately afterwards. The call to flush_writes() in ar_context_run() does not need to be done individually for each AR context, so move it to ohci_enable(). This also makes ohci_enable() clearer because it no longer depends on a side effect of ar_context_run() to flush its own register writes. Finally, the setting of a context's wake bit does not need to be flushed because neither the driver logic nor the API require the CPU to wait for this action. This removes the last MMIO reads from the packet queueing code paths. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-05-10firewire: optimize iso queueing by setting wake only after the last packetClemens Ladisch
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>
2011-05-10Merge tag 'v2.6.39-rc7'Stefan Richter
in order to pull in changes in drivers/media/dvb/firewire/ and sound/firewire/.
2011-05-02firewire: Fix for broken configrom updates in quick successionB.J. Buchalter
Current implementation of ohci_set_config_rom() uses a deferred bus reset via fw_schedule_bus_reset(). If clients add multiple unit descriptors to the config_rom in quick succession, the deferred bus reset may not have fired before succeeding update requests have come in. This can lead to an incorrect partial update of the config_rom for both addition and removal of config_rom descriptors, as the ohci_set_config_rom() routine will return -EBUSY if a previous pending update has not been completed yet; the requested update just gets dropped on the floor. This patch recognizes that the "in-flight" update can be modified until it has been processed by the bus-reset, and the locking in the bus_reset_tasklet ensures that the update is done atomically with respect to modifications made by ohci_set_config_rom(). The -EBUSY error case is simply removed. [Stefan R: The bug always existed at least theoretically. But it became easy to trigger since 2.6.36 commit 02d37bed188c "firewire: core: integrate software-forced bus resets with bus management" which introduced long mandatory delays between janitorial bus resets.] Signed-off-by: Benjamin Buchalter <bj@mhlabs.com> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (trivial style changes) Cc: <stable@kernel.org> # 2.6.36.y and newer
2011-04-19firewire: ohci: optimize find_branch_descriptor()Clemens Ladisch
When z==2, the condition "key == 2" is superfluous because it cannot occur without "b == 3", as a descriptor with b!=3 and key==2 would be an OUTPUT_MORE_IMMEDIATE descriptor which cannot be used alone. Also remove magic numbers and needless computations on the b field. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-04-19firewire: ohci: avoid separate DMA mapping for small AT payloadsClemens Ladisch
For AT packet payloads of up to eight bytes, we have enough unused space in the DMA descriptors list so that we can put a copy of the payload there and thus avoid having to create a separate streaming DMA mapping for the payload buffer. In a CPU-bound microbenchmark that just sends 8-byte packets, bandwidth was measured to increase by 5.7 %, from 1009 KB/s to 1067 KB/s. In practice, the only performance-sensitive usage of small asynchronous packets is the SBP-2 driver's write to the ORB_POINTER register during SCSI command submission. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-04-19firewire: ohci: do not start DMA contexts before link is enabledClemens Ladisch
OHCI 1.1 5.7.3 not only forbids enabling or starting any DMA contexts before the linkEnable bit is set, but also explicitly warns of undefined behaviour if this order is violated. Don't violate it then. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>