aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/dma
Commit message (Collapse)AuthorAge
* ioatdma: add the unisys "i/oat" pci vendor/device idDan Williams2007-07-13
| | | | | | Cc: John Magolan <john.magolan@unisys.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: driver for the iop32x, iop33x, and iop13xx raid enginesDan Williams2007-07-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Intel(R) IOP series of i/o processors integrate an Xscale core with raid acceleration engines. The capabilities per platform are: iop219: (2) copy engines iop321: (2) copy engines (1) xor and block fill engine iop33x: (2) copy and crc32c engines (1) xor, xor zero sum, pq, pq zero sum, and block fill engine iop34x (iop13xx): (2) copy, crc32c, xor, xor zero sum, and block fill engines (1) copy, crc32c, xor, xor zero sum, pq, pq zero sum, and block fill engine The driver supports the features of the async_tx api: * asynchronous notification of operation completion * implicit (interupt triggered) handling of inter-channel transaction dependencies The driver adapts to the platform it is running by two methods. 1/ #include <asm/arch/adma.h> which defines the hardware specific iop_chan_* and iop_desc_* routines as a series of static inline functions 2/ The private platform data attached to the platform_device defines the capabilities of the channels 20070626: Callbacks are run in a tasklet. Given the recent discussion on LKML about killing tasklets in favor of workqueues I did a quick conversion of the driver. Raid5 resync performance dropped from 50MB/s to 30MB/s, so the tasklet implementation remains until a generic softirq interface is available. Changelog: * fixed a slot allocation bug in do_iop13xx_adma_xor that caused too few slots to be requested eventually leading to data corruption * enabled the slot allocation routine to attempt to free slots before returning -ENOMEM * switched the cleanup routine to solely use the software chain and the status register to determine if a descriptor is complete. This is necessary to support other IOP engines that do not have status writeback capability * make the driver iop generic * modified the allocation routines to understand allocating a group of slots for a single operation * added a null xor initialization operation for the xor only channel on iop3xx * support xor operations on buffers larger than the hardware maximum * split the do_* routines into separate prep, src/dest set, submit stages * added async_tx support (dependent operations initiation at cleanup time) * simplified group handling * added interrupt support (callbacks via tasklets) * brought the pending depth inline with ioat (i.e. 4 descriptors) * drop dma mapping methods, suggested by Chris Leech * don't use inline in C files, Adrian Bunk * remove static tasklet declarations * make iop_adma_alloc_slots easier to read and remove chances for a corrupted descriptor chain * fix locking bug in iop_adma_alloc_chan_resources, Benjamin Herrenschmidt * convert capabilities over to dma_cap_mask_t * fixup sparse warnings * add descriptor flush before iop_chan_enable * checkpatch.pl fixes * gpl v2 only correction * move set_src, set_dest, submit to async_tx methods * move group_list and phys to async_tx Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* async_tx: add the async_tx apiDan Williams2007-07-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The async_tx api provides methods for describing a chain of asynchronous bulk memory transfers/transforms with support for inter-transactional dependencies. It is implemented as a dmaengine client that smooths over the details of different hardware offload engine implementations. Code that is written to the api can optimize for asynchronous operation and the api will fit the chain of operations to the available offload resources. I imagine that any piece of ADMA hardware would register with the 'async_*' subsystem, and a call to async_X would be routed as appropriate, or be run in-line. - Neil Brown async_tx exploits the capabilities of struct dma_async_tx_descriptor to provide an api of the following general format: struct dma_async_tx_descriptor * async_<operation>(..., struct dma_async_tx_descriptor *depend_tx, dma_async_tx_callback cb_fn, void *cb_param) { struct dma_chan *chan = async_tx_find_channel(depend_tx, <operation>); struct dma_device *device = chan ? chan->device : NULL; int int_en = cb_fn ? 1 : 0; struct dma_async_tx_descriptor *tx = device ? device->device_prep_dma_<operation>(chan, len, int_en) : NULL; if (tx) { /* run <operation> asynchronously */ ... tx->tx_set_dest(addr, tx, index); ... tx->tx_set_src(addr, tx, index); ... async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param); } else { /* run <operation> synchronously */ ... <operation> ... async_tx_sync_epilog(flags, depend_tx, cb_fn, cb_param); } return tx; } async_tx_find_channel() returns a capable channel from its pool. The channel pool is organized as a per-cpu array of channel pointers. The async_tx_rebalance() routine is tasked with managing these arrays. In the uniprocessor case async_tx_rebalance() tries to spread responsibility evenly over channels of similar capabilities. For example if there are two copy+xor channels, one will handle copy operations and the other will handle xor. In the SMP case async_tx_rebalance() attempts to spread the operations evenly over the cpus, e.g. cpu0 gets copy channel0 and xor channel0 while cpu1 gets copy channel 1 and xor channel 1. When a dependency is specified async_tx_find_channel defaults to keeping the operation on the same channel. A xor->copy->xor chain will stay on one channel if it supports both operation types, otherwise the transaction will transition between a copy and a xor resource. Currently the raid5 implementation in the MD raid456 driver has been converted to the async_tx api. A driver for the offload engines on the Intel Xscale series of I/O processors, iop-adma, is provided in a later commit. With the iop-adma driver and async_tx, raid456 is able to offload copy, xor, and xor-zero-sum operations to hardware engines. On iop342 tiobench showed higher throughput for sequential writes (20 - 30% improvement) and sequential reads to a degraded array (40 - 55% improvement). For the other cases performance was roughly equal, +/- a few percentage points. On a x86-smp platform the performance of the async_tx implementation (in synchronous mode) was also +/- a few percentage points of the original implementation. According to 'top' on iop342 CPU utilization drops from ~50% to ~15% during a 'resync' while the speed according to /proc/mdstat doubles from ~25 MB/s to ~50 MB/s. The tiobench command line used for testing was: tiobench --size 2048 --block 4096 --block 131072 --dir /mnt/raid --numruns 5 * iop342 had 1GB of memory available Details: * if CONFIG_DMA_ENGINE=n the asynchronous path is compiled away by making async_tx_find_channel a static inline routine that always returns NULL * when a callback is specified for a given transaction an interrupt will fire at operation completion time and the callback will occur in a tasklet. if the the channel does not support interrupts then a live polling wait will be performed * the api is written as a dmaengine client that requests all available channels * In support of dependencies the api implicitly schedules channel-switch interrupts. The interrupt triggers the cleanup tasklet which causes pending operations to be scheduled on the next channel * Xor engines treat an xor destination address differently than a software xor routine. To the software routine the destination address is an implied source, whereas engines treat it as a write-only destination. This patch modifies the xor_blocks routine to take a an explicit destination address to mirror the hardware. Changelog: * fixed a leftover debug print * don't allow callbacks in async_interrupt_cond * fixed xor_block changes * fixed usage of ASYNC_TX_XOR_DROP_DEST * drop dma mapping methods, suggested by Chris Leech * printk warning fixups from Andrew Morton * don't use inline in C files, Adrian Bunk * select the API when MD is enabled * BUG_ON xor source counts <= 1 * implicitly handle hardware concerns like channel switching and interrupts, Neil Brown * remove the per operation type list, and distribute operation capabilities evenly amongst the available channels * simplify async_tx_find_channel to optimize the fast path * introduce the channel_table_initialized flag to prevent early calls to the api * reorganize the code to mimic crypto * include mm.h as not all archs include it in dma-mapping.h * make the Kconfig options non-user visible, Adrian Bunk * move async_tx under crypto since it is meant as 'core' functionality, and the two may share algorithms in the future * move large inline functions into c files * checkpatch.pl fixes * gpl v2 only correction Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
* dmaengine: make clients responsible for managing channelsDan Williams2007-07-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The current implementation assumes that a channel will only be used by one client at a time. In order to enable channel sharing the dmaengine core is changed to a model where clients subscribe to channel-available-events. Instead of tracking how many channels a client wants and how many it has received the core just broadcasts the available channels and lets the clients optionally take a reference. The core learns about the clients' needs at dma_event_callback time. In support of multiple operation types, clients can specify a capability mask to only be notified of channels that satisfy a certain set of capabilities. Changelog: * removed DMA_TX_ARRAY_INIT, no longer needed * dma_client_chan_free -> dma_chan_release: switch to global reference counting only at device unregistration time, before it was also happening at client unregistration time * clients now return dma_state_client to dmaengine (ack, dup, nak) * checkpatch.pl fixes * fixup merge with git-ioat Cc: Chris Leech <christopher.leech@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: David S. Miller <davem@davemloft.net>
* dmaengine: refactor dmaengine around dma_async_tx_descriptorDan Williams2007-07-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current dmaengine interface defines mutliple routines per operation, i.e. dma_async_memcpy_buf_to_buf, dma_async_memcpy_buf_to_page etc. Adding more operation types (xor, crc, etc) to this model would result in an unmanageable number of method permutations. Are we really going to add a set of hooks for each DMA engine whizbang feature? - Jeff Garzik The descriptor creation process is refactored using the new common dma_async_tx_descriptor structure. Instead of per driver do_<operation>_<dest>_to_<src> methods, drivers integrate dma_async_tx_descriptor into their private software descriptor and then define a 'prep' routine per operation. The prep routine allocates a descriptor and ensures that the tx_set_src, tx_set_dest, tx_submit routines are valid. Descriptor creation and submission becomes: struct dma_device *dev; struct dma_chan *chan; struct dma_async_tx_descriptor *tx; tx = dev->device_prep_dma_<operation>(chan, len, int_flag) tx->tx_set_src(dma_addr_t, tx, index /* for multi-source ops */) tx->tx_set_dest(dma_addr_t, tx, index) tx->tx_submit(tx) In addition to the refactoring, dma_async_tx_descriptor also lays the groundwork for definining cross-channel-operation dependencies, and a callback facility for asynchronous notification of operation completion. Changelog: * drop dma mapping methods, suggested by Chris Leech * fix ioat_dma_dependency_added, also caught by Andrew Morton * fix dma_sync_wait, change from Andrew Morton * uninline large functions, change from Andrew Morton * add tx->callback = NULL to dmaengine calls to interoperate with async_tx calls * hookup ioat_tx_submit * convert channel capabilities to a 'cpumask_t like' bitmap * removed DMA_TX_ARRAY_INIT, no longer needed * checkpatch.pl fixes * make set_src, set_dest, and tx_submit descriptor specific methods * fixup git-ioat merge * move group_list and phys to dma_async_tx_descriptor Cc: Jeff Garzik <jeff@garzik.org> Cc: Chris Leech <christopher.leech@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: David S. Miller <davem@davemloft.net>
* I/OAT: fix I/OAT for kexecDan Aloni2007-07-11
| | | | | | | | | | | | Under kexec, I/OAT initialization breaks over busy resources because the previous kernel did not release them. I'm not sure this fix can be considered a complete one but it works for me. I guess something similar to the *_remove method should occur there.. Signed-off-by: Dan Aloni <da-x@monatomic.org> Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* ioatdma: Remove the use of writeq from the ioatdma driverChris Leech2007-07-11
| | | | | | | There's only one now anyway, and it's not in a performance path, so make it behave the same on 32-bit and 64-bit CPUs. Signed-off-by: Chris Leech <christopher.leech@intel.com>
* ioatdma: Remove the wrappers around read(bwl)/write(bwl) in ioatdmaChris Leech2007-07-11
| | | | Signed-off-by: Chris Leech <christopher.leech@intel.com>
* drivers/dma: handle sysfs errorsJeff Garzik2007-07-11
| | | | | | | From: Jeff Garzik <jeff@garzik.org> Signed-off-by: Jeff Garzik <jeff@garzik.org> Signed-off-by: Chris Leech <christopher.leech@intel.com>
* ioatdma: Push pending transactions to hardware more frequentlyChris Leech2007-07-11
| | | | | | | | Every 20 descriptors turns out to be to few append commands with newer/faster CPUs. Pushing every 4 still cuts down on MMIO writes to an acceptable level without letting the DMA engine run out of work. Signed-off-by: Chris Leech <christopher.leech@intel.com>
* IOATDMA: fix section mismatchesRandy Dunlap2007-06-28
| | | | | | | | | | | | | | | | | | | | Rename struct pci_driver data so that false section mismatch warnings won't be produced. Sam, ISTM that depending on variable names is the weakest & worst part of modpost section checking. Should __init_refok work here? I got build errors when I tried to use it, probably because the struct pci_driver probe and remove methods are not marked "__init_refok". WARNING: drivers/dma/ioatdma.o(.data+0x10): Section mismatch: reference to .init.text: (between 'ioat_pci_drv' and 'ioat_pci_tbl') WARNING: drivers/dma/ioatdma.o(.data+0x14): Section mismatch: reference to .exit.text: (between 'ioat_pci_drv' and 'ioat_pci_tbl') Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Chris Leech <christopher.leech@intel.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [S390] Kconfig: unwanted menus for s390.Martin Schwidefsky2007-05-10
| | | | | | | Disable some more menus in the configuration files that are of no interest to a s390 machine. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [PATCH] rm pointless dmaengine exportsDavid Brownell2007-03-16
| | | | | | | | | | | | | | | | This removes several pointless exports from drivers/dma/dmaengine.c; the dma_async_memcpy_*() functions are inlined by <linux/dmaengine.h> so those exports are inappropriate. It also moves the existing EXPORT_SYMBOL declarations next to their functions, so it's now trivial to confirm one-to-one correspondence between exports and nonstatic symbols. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] slab: remove SLAB_KERNELChristoph Lameter2006-12-07
| | | | | | | | SLAB_KERNEL is an alias of GFP_KERNEL. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] drivers/dma trivial annotationsAl Viro2006-10-10
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells2006-10-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
* [I/OAT]: Remove pci_module_init() from Intel I/OAT DMA engineHenrik Kretzschmar2006-07-21
| | | | | | | Changes pci_module_init() to pci_register_driver(). Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IOAT]: fix kernel-doc in source filesRandy Dunlap2006-07-03
| | | | | | | | | Fix kernel-doc warnings in drivers/dma/: - use correct function & parameter names - add descriptions where omitted Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IOAT]: Fix a warning in ioatdmaBenoit Boissinot2006-07-03
| | | | | | | | | drivers/dma/ioatdma.c: In function 'ioat_init_module': drivers/dma/ioatdma.c:830: warning: control reaches end of non-void function Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IOAT]: drivers/dma/iovlock.c: make num_pages_spanned() staticAdrian Bunk2006-07-03
| | | | | | | | This patch makes the needlessly global num_pages_spanned() static. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IOAT]: fix sparse ulong warningRandy Dunlap2006-07-03
| | | | | | | | | | | Fix sparse warning: drivers/dma/ioatdma.c:444:32: warning: constant 0xFFFFFFFFFFFFFFC0 is so big it is unsigned long Also needs a MAINTAINERS entry. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [PATCH] irq-flags: misc drivers: Use the new IRQF_ constantsThomas Gleixner2006-07-02
| | | | | | | | | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [IOAT]: Do not dereference THIS_MODULE directly to set unsafe.David S. Miller2006-06-26
| | | | | | | | Use the __unsafe() macro instead. Noticed by Miles Lane. Signed-off-by: David S. Miller <davem@davemloft.net>
* [I/OAT]: Do not use for_each_cpu().Andrew Morton2006-06-18
| | | | | | | | for_each_cpu() is going away (and is gone in -mm). Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [I/OAT]: Utility functions for offloading sk_buff to iovec copiesChris Leech2006-06-18
| | | | | | | | Provides for pinning user space pages in memory, copying to iovecs, and copying from sk_buffs including fragmented and chained sk_buffs. Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [I/OAT]: Setup the networking subsystem as a DMA clientChris Leech2006-06-18
| | | | | | | Attempts to allocate per-CPU DMA channels Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [I/OAT]: Move PCI_DEVICE_ID_INTEL_IOAT to linux/pci_ids.hDavid S. Miller2006-06-18
| | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* [I/OAT]: ioatdma.c needs linux/dma-mapping.hDavid S. Miller2006-06-18
| | | | | | For DMA_*_MASK defines. Signed-off-by: David S. Miller <davem@davemloft.net>
* [I/OAT]: Driver for the Intel(R) I/OAT DMA engineChris Leech2006-06-18
| | | | | | | Adds a new ioatdma driver Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [I/OAT]: DMA memcpy subsystemChris Leech2006-06-18
Provides an API for offloading memory copies to DMA devices Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>