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path: root/drivers/firewire/core.h
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2010-07-29firewire: add isochronous multichannel receptionStefan Richter
This adds the DMA context programming and userspace ABI for multichannel reception, i.e. for listening on multiple channel numbers by means of a single DMA context. The use case is reception of more streams than there are IR DMA units offered by the link layer. This is already implemented by the older ohci1394 + ieee1394 + raw1394 stack. And as discussed recently on linux1394-devel, this feature is occasionally used in practice. The big drawbacks of this mode are that buffer layout and interrupt generation necessarily differ from single-channel reception: Headers and trailers are not stripped from packets, packets are not aligned with buffer chunks, interrupts are per buffer chunk, not per packet. These drawbacks also cause a rather hefty code footprint to support this rarely used OHCI-1394 feature. (367 lines added, among them 94 lines of added userspace ABI documentation.) This implementation enforces that a multichannel reception context may only listen to channels to which no single-channel context on the same link layer is presently listening to. OHCI-1394 would allow to overlay single-channel contexts by the multi-channel context, but this would be a departure from the present first-come-first-served policy of IR context creation. The implementation is heavily based on an earlier one by Jay Fenlason. Thanks Jay. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23firewire: cdev: add PHY pingingStefan Richter
This extends the FW_CDEV_IOC_SEND_PHY_PACKET ioctl() for /dev/fw* to be useful for ping time measurements. One application for it would be gap count optimization in userspace that is based on ping times rather than hop count. (The latter is implemented in firewire-core itself but is not applicable to beta PHYs that act as repeater.) Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23firewire: cdev: add PHY packet receptionStefan Richter
Add an FW_CDEV_IOC_RECEIVE_PHY_PACKETS ioctl() and FW_CDEV_EVENT_PHY_PACKET_RECEIVED poll()/read() event for /dev/fw*. This can be used to get information from remote PHYs by remote access PHY packets. This is also the 2nd half of the functionality (the receive part) to support a userspace implementation of a VersaPHY transaction layer. Safety considerations: - PHY packets are generally broadcasts, hence some kind of elevated privileges should be required of a process to be able to listen in on PHY packets. This implementation assumes that a process that is allowed to open the /dev/fw* of a local node does have this privilege. There was an inconclusive discussion about introducing POSIX capabilities as a means to check for user privileges for these kinds of operations. Other limitations: - PHY packet reception may be switched on by ioctl() but cannot be switched off again. It would be trivial to provide an off switch, but this is not worth the code. The client should simply close() the fd then, or just ignore further events. - For sake of simplicity of API and kernel-side implementation, no filter per packet content is provided. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-13firewire: core: integrate software-forced bus resets with bus managementStefan Richter
Bus resets which are triggered - by the kernel drivers after updates of the local nodes' config ROM, - by userspace software via ioctl shall be deferred until after >=2 seconds after the last bus reset. If multiple modifications of the local nodes' config ROM happen in a row, only a single bus reset should happen after them. When the local node's link goes from inactive to active or vice versa, and at the two occasions of bus resets mentioned above --- and if the current gap count differs from 63 --- the bus reset should be preceded by a PHY configuration packet that reaffirms the gap count. Otherwise a bus manager would have to reset the bus again right after that. This is necessary to promote bus stability, e.g. leave grace periods for allocations and reallocations of isochronous channels and bandwidth, SBP-2 reconnections etc.; see IEEE 1394 clause 8.2.1. This change implements all of the above by moving bus reset initiation into a delayed work (except for bus resets which are triggered by the bus manager workqueue job and are performed there immediately). It comes with a necessary addition to the card driver methods that allows to get the current gap count from PHY registers. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19firewire: rename CSR access driver methodsStefan Richter
Rather than "read a Control and Status Registers (CSR) Architecture register" I prefer to say "read a Control and Status Register". Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19firewire: normalize STATE_CLEAR/SET CSR access interfaceStefan Richter
Push the maintenance of STATE_CLEAR/SET.abdicate down into the card driver. This way, the read/write_csr_reg driver method works uniformly across all CSR offsets. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19firewire: replace get_features card driver hookStefan Richter
by feature variables in the fw_card struct. The hook appeared to be an unnecessary abstraction in the card driver interface. Cleaner would be to pass those feature flags as arguments to fw_card_initialize() or fw_card_add(), but the FairnessControl register is in the SCLK domain and may therefore not be accessible while Link Power Status is off, i.e. before the card->driver->enable call from fw_card_add(). Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-10firewire: allocate broadcast channel in hardwareClemens Ladisch
On OHCI 1.1 controllers, let the hardware allocate the broadcast channel automatically. This removes a theoretical race condition directly after a bus reset where it could be possible to read the channel allocation register with channel 31 still being unallocated. Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10firewire: core: add CSR abdicate supportClemens Ladisch
Implement the abdicate bit, which is required for bus manager capable nodes and tested by the Base 1394 Test Suite. Finally, something to do at a command reset! :-) Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10firewire: add CSR cmstr supportClemens Ladisch
Implement the cmstr bit, which is required for cycle master capable nodes and tested for by the Base 1394 Test Suite. This bit allows the bus master to disable cycle start packets; there are bus master implementations that actually do this. Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10firewire: add CSR PRIORITY_BUDGET supportClemens Ladisch
If supported by the OHCI controller, implement the PRIORITY_BUDGET register, which is required for nodes that can use asynchronous priority arbitration. To allow the core to determine what features the lowlevel device supports, add a new card driver callback. Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10firewire: add CSR NODE_IDS supportClemens Ladisch
The NODE_IDS register, and especially its bus_id field, is quite useless because 1394.1 requires that the bus_id field always stays 0x3ff. However, the 1394 specification requires this register on all transaction capable nodes, and the Base 1394 Test Suite tests for it, so we better implement it. Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10firewire: add read_csr_reg driver callbackClemens Ladisch
To prepare for the following additions of more OHCI-implemented CSR registers, replace the get_cycle_time driver callback with a generic CSR register callback. Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-09firewire: check cdev response lengthClemens Ladisch
Add a check that the data length in the SEND_RESPONSE ioctl is correct. Incidentally, this also fixes the previously wrong response length of software-handled lock requests. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-05-18firewire: core: use separate timeout for each transactionClemens Ladisch
Using a single timeout for all transaction that need to be flushed does not work if the submission of new transactions can defer the timeout indefinitely into the future. We need to have timeouts that do not change due to other transactions; the simplest way to do this is with a separate timer for each transaction. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (+ one lockdep annotation)
2010-04-10firewire: ohci: enable 1394a enhancementsClemens Ladisch
The OHCI spec says that, if the programPhyEnable bit is set, the driver is responsible for configuring the IEEE1394a enhancements within the PHY and the link consistently. So do this. Also add a quirk to allow disabling these enhancements; this is needed for the TSB12LV22 where ack accelerations are buggy (erratum b). Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-10firewire: ohci: do not clear PHY interrupt status inadvertentlyClemens Ladisch
The interrupt status bits in PHY register 5 are cleared by writing a one bit. To avoid clearing them unadvertently, do not write them back when they were read as set, but only when they have been explicitly requested to be set. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-02-20firewire: remove incomplete Bus_Time CSR supportStefan Richter
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: HÃ¥kan 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>
2009-10-14firewire: core: optimize Topology Map creationStefan Richter
The Topology Map of the local node was created in CPU byte order, then a temporary big endian copy was created to compute the CRC, and when a read request to the Topology Map arrived it had to be converted to big endian byte order again. We now generate it in big endian byte order in the first place. This also rids us of 1000 bytes stack usage in tasklet context. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-10-14firewire: optimize config ROM creationStefan Richter
The config ROM image of the local node was created in CPU byte order, then a temporary big endian copy was created to compute the CRC, and finally the card driver created its own big endian copy. We now generate it in big endian byte order in the first place to avoid one byte order conversion and the temporary on-stack copy of the ROM image (1000 bytes stack usage in process context). Furthermore, two 1000 bytes memset()s are replaced by one 1000 bytes - ROM length sized memset. The trivial fw_memcpy_{from,to}_be32() helpers are now superfluous and removed. The newly added __compute_block_crc() function will be folded into fw_compute_block_crc() in a subsequent change. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-09-12firewire: core: header file cleanupStefan Richter
fw_card_get, fw_card_put, fw_card_release are currently not exported for use outside the firewire-core. Move their definitions/ declarations from the subsystem header file to the core header file. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-25firewire: core: do not DMA-map stack addressesStefan Richter
The DMA mapping API cannot map on-stack addresses, as explained in Documentation/DMA-mapping.txt. Convert the two cases of on-stack packet payload buffers in firewire-core (payload of lock requests in the bus manager work and in iso resource management) to slab-allocated memory. There are a number on-stack buffers for quadlet write or quadlet read requests in firewire-core and firewire-sbp2. These are harmless; they are copied to/ from card driver internal DMA buffers since quadlet payloads are inlined with packet headers. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-14firewire: add IPv4 supportJay Fenlason
Implement IPv4 over IEEE 1394 as per RFC 2734 for the newer firewire stack. This feature has only been present in the older ieee1394 stack via the eth1394 driver. Still to do: - fix ipv4_priv and ipv4_node lifetime logic - fix determination of speeds and max payloads - fix bus reset handling - fix unaligned memory accesses - fix coding style - further testing/ improvement of fragment reassembly - perhaps multicast support Signed-off-by: Jay Fenlason <fenlason@redhat.com> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (rebased, copyright note, changelog)
2009-06-06firewire: core: prepare for non-core children of card devicesStefan Richter
The IP-over-1394 driver will add child devices beneath card devices which are not of type fw_device. Hence firewire-core's callbacks in device_for_each_child() and device_find_child() need to check for the device type now. Initial version written by Jay Fenlason. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-05firewire: reorganize header filesStefan Richter
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>