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path: root/include/linux/dmaengine.h
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2009-12-10dmaengine: clarify the meaning of the DMA_CTRL_ACK flagGuennadi Liakhovetski
DMA_CTRL_ACK's description applies to its clear state, not to its set state. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08Merge branch 'dmaengine' into async-tx-nextDan Williams
Conflicts: crypto/async_tx/async_xor.c drivers/dma/ioat/dma_v2.h drivers/dma/ioat/pci.c drivers/md/raid5.c
2009-09-08dmaengine: kill tx_listDan Williams
The tx_list attribute of struct dma_async_tx_descriptor is common to most, but not all dma driver implementations. None of the upper level code (dmaengine/async_tx) uses it, so allow drivers to implement it locally if they need it. This saves sizeof(struct list_head) bytes for drivers that do not manage descriptors with a linked list (e.g.: ioatdma v2,3). Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08dmaengine, async_tx: support alignment checksDan Williams
Some engines have transfer size and address alignment restrictions. Add a per-operation alignment property to struct dma_device that the async routines and dmatest can use to check alignment capabilities. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08dmaengine: cleanup unused transaction typesDan Williams
No drivers currently implement these operation types, so they can be deleted. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08dmaengine, async_tx: add a "no channel switch" allocatorDan Williams
Channel switching is problematic for some dmaengine drivers as the architecture precludes separating the ->prep from ->submit. In these cases the driver can select ASYNC_TX_DISABLE_CHANNEL_SWITCH to modify the async_tx allocator to only return channels that support all of the required asynchronous operations. For example MD_RAID456=y selects support for asynchronous xor, xor validate, pq, pq validate, and memcpy. When ASYNC_TX_DISABLE_CHANNEL_SWITCH=y any channel with all these capabilities is marked DMA_ASYNC_TX allowing async_tx_find_channel() to quickly locate compatible channels with the guarantee that dependency chains will remain on one channel. When ASYNC_TX_DISABLE_CHANNEL_SWITCH=n async_tx_find_channel() may select channels that lead to operation chains that need to cross channel boundaries using the async_tx channel switch capability. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08dmaengine: add fence supportDan Williams
Some engines optimize operation by reading ahead in the descriptor chain such that descriptor2 may start execution before descriptor1 completes. If descriptor2 depends on the result from descriptor1 then a fence is required (on descriptor2) to disable this optimization. The async_tx api could implicitly identify dependencies via the 'depend_tx' parameter, but that would constrain cases where the dependency chain only specifies a completion order rather than a data dependency. So, provide an ASYNC_TX_FENCE to explicitly identify data dependencies. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08Merge branch 'md-raid6-accel' into ioat3.2Dan Williams
Conflicts: include/linux/dmaengine.h
2009-08-29async_tx: add support for asynchronous GF multiplicationDan Williams
[ Based on an original patch by Yuri Tikhonov ] This adds support for doing asynchronous GF multiplication by adding two additional functions to the async_tx API: async_gen_syndrome() does simultaneous XOR and Galois field multiplication of sources. async_syndrome_val() validates the given source buffers against known P and Q values. When a request is made to run async_pq against more than the hardware maximum number of supported sources we need to reuse the previous generated P and Q values as sources into the next operation. Care must be taken to remove Q from P' and P from Q'. For example to perform a 5 source pq op with hardware that only supports 4 sources at a time the following approach is taken: p, q = PQ(src0, src1, src2, src3, COEF({01}, {02}, {04}, {08})) p', q' = PQ(p, q, q, src4, COEF({00}, {01}, {00}, {10})) p' = p + q + q + src4 = p + src4 q' = {00}*p + {01}*q + {00}*q + {10}*src4 = q + {10}*src4 Note: 4 is the minimum acceptable maxpq otherwise we punt to synchronous-software path. The DMA_PREP_CONTINUE flag indicates to the driver to reuse p and q as sources (in the above manner) and fill the remaining slots up to maxpq with the new sources/coefficients. Note1: Some devices have native support for P+Q continuation and can skip this extra work. Devices with this capability can advertise it with dma_set_maxpq. It is up to each driver how to handle the DMA_PREP_CONTINUE flag. Note2: The api supports disabling the generation of P when generating Q, this is ignored by the synchronous path but is implemented by some dma devices to save unnecessary writes. In this case the continuation algorithm is simplified to only reuse Q as a source. Cc: H. Peter Anvin <hpa@zytor.com> Cc: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-08-29async_tx: add sum check flagsDan Williams
Replace the flat zero_sum_result with a collection of flags to contain the P (xor) zero-sum result, and the soon to be utilized Q (raid6 reed solomon syndrome) zero-sum result. Use the SUM_CHECK_ namespace instead of DMA_ since these flags will be used on non-dma-zero-sum enabled platforms. Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-05-12ioatdma: fix "ioatdma frees DMA memory with wrong function"Maciej Sosnowski
as reported by Alexander Beregalov <a.beregalov@gmail.com> ioatdma 0000:00:08.0: DMA-API: device driver frees DMA memory with wrong function [device address=0x000000007f76f800] [size=2000 bytes] [map ped as single] [unmapped as page] The ioatdma driver was unmapping all regions (either allocated as page or single) using unmap_page. This patch lets dma driver recognize if unmap_single or unmap_page should be used. It introduces two new dma control flags: DMA_COMPL_SRC_UNMAP_SINGLE and DMA_COMPL_DEST_UNMAP_SINGLE. They should be set to indicate dma driver to do dma-unmapping as single (first one for the source, tha latter for the destination). If respective flag is not set, the driver assumes dma-unmapping as page. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Reported-by: Alexander Beregalov <a.beregalov@gmail.com> Tested-by: Alexander Beregalov <a.beregalov@gmail.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-04-08async_tx: rename zero_sum to valDan Williams
'zero_sum' does not properly describe the operation of generating parity and checking that it validates against an existing buffer. Change the name of the operation to 'val' (for 'validate'). This is in anticipation of the p+q case where it is a requirement to identify the target parity buffers separately from the source buffers, because the target parity buffers will not have corresponding pq coefficients. Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-26dmaengine: Add privatecnt to revert DMA_PRIVATE propertyAtsushi Nemoto
Currently dma_request_channel() set DMA_PRIVATE capability but never clear it. So if a public channel was once grabbed by dma_request_channel(), the device stay PRIVATE forever. Add privatecnt member to dma_device to correctly revert it. [lg@denx.de: fix bad usage of 'chan' in dma_async_device_register] Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-25dmaengine: allow dma support for async_tx to be toggledDan Williams
Provide a config option for blocking the allocation of dma channels to the async_tx api. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-25dmaengine: kill some unused headersDan Williams
The dmaengine redux left some unneeded headers in include/linux/dmaengine.h, clean them up. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-08Merge branch 'fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: dmatest: fix use after free in dmatest_exit ipu_idmac: fix spinlock type iop-adma, mv_xor: fix mem leak on self-test setup failure fsldma: fix off by one in dma_halt I/OAT: fail self-test if callback test reaches timeout I/OAT: update driver version and copyright dates I/OAT: list usage cleanup I/OAT: set tcp_dma_copybreak to 256k for I/OAT ver.3 I/OAT: cancel watchdog before dma remove I/OAT: fail initialization on zero channels detection I/OAT: do not set DCACTRL_CMPL_WRITE_ENABLE for I/OAT ver.3 I/OAT: add verification for proper APICID_TAG_MAP setting by BIOS dmaengine: update kerneldoc
2009-02-18atmel-mci: fix initialization of dma slave dataDan Williams
The conversion of atmel-mci to dma_request_channel missed the initialization of the channel dma_slave information. The filter_fn passed to dma_request_channel is responsible for initializing the channel's private data. This implementation has the additional benefit of enabling a generic client-channel data passing mechanism. Reviewed-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-11dmaengine: update kerneldocJohannes Weiner
Some of the kerneldoc comments in the dmaengine header describe already removed structure members. Remove them. Also add a short description for dma_device->device_is_tx_complete. Signed-off-by: Johannes Weiner <jw@emlix.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-02-06net_dma: call dmaengine_get only if NET_DMA enabledDavid S. Miller
Based upon a patch from Atsushi Nemoto <anemo@mba.ocn.ne.jp> -------------------- The commit 649274d993212e7c23c0cb734572c2311c200872 ("net_dma: acquire/release dma channels on ifup/ifdown") added unconditional call of dmaengine_get() to net_dma. The API should be called only if NET_DMA was enabled. -------------------- Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Dan Williams <dan.j.williams@intel.com>
2009-01-26Merge branch 'fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: i.MX31: framebuffer driver i.MX31: Image Processing Unit DMA and IRQ drivers dmaengine: add async_tx_clear_ack() macro dmaengine: dma_issue_pending_all == nop when CONFIG_DMA_ENGINE=n dmaengine: kill some dubious WARN_ONCEs fsldma: print correct IRQ on mpc83xx fsldma: check for NO_IRQ in fsl_dma_chan_remove() dmatest: Use custom map/unmap for destination buffer fsldma: use a valid 'device' for dma_pool_create dmaengine: fix dependency chaining
2009-01-19dmaengine: add async_tx_clear_ack() macroGuennadi Liakhovetski
To complete the DMA_CTRL_ACK handling API add a async_tx_clear_ack() macro. Signed-off-by: Guennadi Liakhovetski <lg@denx.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-19dmaengine: dma_issue_pending_all == nop when CONFIG_DMA_ENGINE=nDan Williams
The device list will always be empty in this configuration, so no need to walk the list. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-11net_dma: acquire/release dma channels on ifup/ifdownDan Williams
The recent dmaengine rework removed the capability to remove dma device driver modules while net_dma is active. Rather than notify dmaengine-clients that channels are trying to be removed, we now rely on clients to notify dmaengine when they no longer have a need for channels. Teach net_dma to release channels by taking dmaengine references at netdevice open and dropping references at netdevice close. Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-06dmaengine: use idr for registering dma device numbersDan Williams
This brings some predictability to dma device numbers, i.e. an rmmod/insmod cycle may now result in /sys/class/dma/dma0chan0 being restored rather than /sys/class/dma/dma1chan0 appearing. Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: add a release for dma class devices and dependent infrastructureDan Williams
Resolves: WARNING: at drivers/base/core.c:122 device_release+0x4d/0x52() Device 'dma0chan0' does not have a release() function, it is broken and must be fixed. The dma_chan_dev object is introduced to gear-match sysfs kobject and dmaengine channel lifetimes. When a channel is removed access to the sysfs entries return -ENODEV until the kobject can be released. The bulk of the change is updates to existing code to handle the extra layer of indirection between a dma_chan and its struct device. Reported-by: Alexander Beregalov <a.beregalov@gmail.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: kill enum dma_state_clientDan Williams
DMA_NAK is now useless. We can just use a bool instead. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: remove 'bigref' infrastructureDan Williams
Reference counting is done at the module level so clients need not worry that a channel will leave while they are actively using dmaengine. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: kill struct dma_client and supporting infrastructureDan Williams
All users have been converted to either the general-purpose allocator, dma_find_channel, or dma_request_channel. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: replace dma_async_client_register with dmaengine_getDan Williams
Now that clients no longer need to be notified of channel arrival dma_async_client_register can simply increment the dmaengine_ref_count. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06atmel-mci: convert to dma_request_channel and down-level dma_slaveDan Williams
dma_request_channel provides an exclusive channel, so we no longer need to pass slave data through dmaengine. Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmatest: convert to dma_request_channelDan Williams
Replace the client registration infrastructure with a custom loop to poll for channels. Once dma_request_channel returns NULL stop asking for channels. A userspace side effect of this change if that loading the dmatest module before loading a dma driver will result in no channels being found, previously dmatest would get a callback. To facilitate testing in the built-in case dmatest_init is marked as a late_initcall. Another side effect is that channels under test can not be used for any other purpose. Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: introduce dma_request_channel and private channelsDan Williams
This interface is primarily for device-to-memory clients which need to search for dma channels with platform-specific characteristics. The prototype is: struct dma_chan *dma_request_channel(dma_cap_mask_t mask, dma_filter_fn filter_fn, void *filter_param); When the optional 'filter_fn' parameter is set to NULL dma_request_channel simply returns the first channel that satisfies the capability mask. Otherwise, when the mask parameter is insufficient for specifying the necessary channel, the filter_fn routine can be used to disposition the available channels in the system. The filter_fn routine is called once for each free channel in the system. Upon seeing a suitable channel filter_fn returns DMA_ACK which flags that channel to be the return value from dma_request_channel. A channel allocated via this interface is exclusive to the caller, until dma_release_channel() is called. To ensure that all channels are not consumed by the general-purpose allocator the DMA_PRIVATE capability is provided to exclude a dma_device from general-purpose (memory-to-memory) consideration. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: provide a common 'issue_pending_all' implementationDan Williams
async_tx and net_dma each have open-coded versions of issue_pending_all, so provide a common routine in dmaengine. The implementation needs to walk the global device list, so implement rcu to allow dma_issue_pending_all to run lockless. Clients protect themselves from channel removal events by holding a dmaengine reference. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: centralize channel allocation, introduce dma_find_channelDan Williams
Allowing multiple clients to each define their own channel allocation scheme quickly leads to a pathological situation. For memory-to-memory offload all clients can share a central allocator. This simply moves the existing async_tx allocator to dmaengine with minimal fixups: * async_tx.c:get_chan_ref_by_cap --> dmaengine.c:nth_chan * async_tx.c:async_tx_rebalance --> dmaengine.c:dma_channel_rebalance * split out common code from async_tx.c:__async_tx_find_channel --> dma_find_channel Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: up-level reference counting to the module levelDan Williams
Simply, if a client wants any dmaengine channel then prevent all dmaengine modules from being removed. Once the clients are done re-enable module removal. Why?, beyond reducing complication: 1/ Tracking reference counts per-transaction in an efficient manner, as is currently done, requires a complicated scheme to avoid cache-line bouncing effects. 2/ Per-transaction ref-counting gives the false impression that a dma-driver can be gracefully removed ahead of its user (net, md, or dma-slave) 3/ None of the in-tree dma-drivers talk to hot pluggable hardware, but if such an engine were built one day we still would not need to notify clients of remove events. The driver can simply return NULL to a ->prep() request, something that is much easier for a client to handle. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-05dmaengine: remove dependency on async_txDan Williams
async_tx.ko is a consumer of dma channels. A circular dependency arises if modules in drivers/dma rely on common code in async_tx.ko. It prevents either module from being unloaded. Move dma_wait_for_async_tx and async_tx_run_dependencies to dmaeninge.o where they should have been from the beginning. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-07-17async_tx: make async_tx_test_ack a boolean routineDan Williams
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-07-08dmaengine: Add slave DMA interfaceHaavard Skinnemoen
This patch adds the necessary interfaces to the DMA Engine framework to use functionality found on most embedded DMA controllers: DMA from and to I/O registers with hardware handshaking. In this context, hardware hanshaking means that the peripheral that owns the I/O registers in question is able to tell the DMA controller when more data is available for reading, or when there is room for more data to be written. This usually happens internally on the chip, but these signals may also be exported outside the chip for things like IDE DMA, etc. A new struct dma_slave is introduced. This contains information that the DMA engine driver needs to set up slave transfers to and from a slave device. Most engines supporting DMA slave transfers will want to extend this structure with controller-specific parameters. This additional information is usually passed from the platform/board code through the client driver. A "slave" pointer is added to the dma_client struct. This must point to a valid dma_slave structure iff the DMA_SLAVE capability is requested. The DMA engine driver may use this information in its device_alloc_chan_resources hook to configure the DMA controller for slave transfers from and to the given slave device. A new operation for preparing slave DMA transfers is added to struct dma_device. This takes a scatterlist and returns a single descriptor representing the whole transfer. Another new operation for terminating all pending transfers is added as well. The latter is needed because there may be errors outside the scope of the DMA Engine framework that may require DMA operations to be terminated prematurely. DMA Engine drivers may extend the dma_device, dma_chan and/or dma_slave_descriptor structures to allow controller-specific operations. The client driver can detect such extensions by looking at the DMA Engine's struct device, or it can request a specific DMA Engine device by setting the dma_dev field in struct dma_slave. dmaslave interface changes since v4: * Fix checkpatch errors * Fix changelog (there are no slave descriptors anymore) dmaslave interface changes since v3: * Use dma_data_direction instead of a new enum * Submit slave transfers as scatterlists * Remove the DMA slave descriptor struct dmaslave interface changes since v2: * Add a dma_dev field to struct dma_slave. If set, the client can only be bound to the DMA controller that corresponds to this device. This allows controller-specific extensions of the dma_slave structure; if the device matches, the controller may safely assume its extensions are present. * Move reg_width into struct dma_slave as there are currently no users that need to be able to set the width on a per-transfer basis. dmaslave interface changes since v1: * Drop the set_direction and set_width descriptor hooks. Pass the direction and width to the prep function instead. * Declare a dma_slave struct with fixed information about a slave, i.e. register addresses, handshake interfaces and such. * Add pointer to a dma_slave struct to dma_client. Can be NULL if the DMA_SLAVE capability isn't requested. * Drop the set_slave device hook since the alloc_chan_resources hook now has enough information to set up the channel for slave transfers. Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-07-08dmaengine: add DMA_COMPL_SKIP_{SRC,DEST}_UNMAP flags to control dma unmapDan Williams
In some cases client code may need the dma-driver to skip the unmap of source and/or destination buffers. Setting these flags indicates to the driver to skip the unmap step. In this regard async_xor is currently broken in that it allows the destination buffer to be unmapped while an operation is still in progress, i.e. when the number of sources exceeds the hardware channel's maximum (fixed in a subsequent patch). Acked-by: Saeed Bishara <saeed@marvell.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-07-08dmaengine: Add dma_client parameter to device_alloc_chan_resourcesHaavard Skinnemoen
A DMA controller capable of doing slave transfers may need to know a few things about the slave when preparing the channel. We don't want to add this information to struct dma_channel since the channel hasn't yet been bound to a client at this point. Instead, pass a reference to the client requesting the channel to the driver's device_alloc_chan_resources hook so that it can pick the necessary information from the dma_client struct by itself. [dan.j.williams@intel.com: fixed up fsldma and mv_xor] Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-07-08dmaengine: track the number of clients using a channelDan Williams
Haavard's dma-slave interface would like to test for exclusive access to a channel. The standard channel refcounting is not sufficient in that it tracks more than just client references, it is also inaccurate as reference counts are percpu until the channel is removed. This change also enables a future fix to deallocate resources when a client declines to use a capable channel. Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-04-21DMA engine: typo fixesSebastian Siewior
Spelling fixes for dmaengine.[ch] Signed-off-by: Sebastian Siewior <bigeasy@linutronix.de> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
2008-04-17dmaengine: ack to flags: make use of the unused bits in the 'ack' fieldDan Williams
'ack' is currently a simple integer that flags whether or not a client is done touching fields in the given descriptor. It is effectively just a single bit of information. Converting this to a flags parameter allows the other bits to be put to use to control completion actions, like dma-unmap, and capture results, like xor-zero-sum == 0. Changes are one of: 1/ convert all open-coded ->ack manipulations to use async_tx_ack and async_tx_test_ack. 2/ set the ack bit at prep time where possible 3/ make drivers store the flags at prep time 4/ add flags to the device_prep_dma_interrupt prototype Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-04-17async_tx: kill ->device_dependency_addedDan Williams
DMA drivers no longer need to be notified of dependency submission events as async_tx_run_dependencies and async_tx_channel_switch will handle the scheduling and execution of dependent operations. [sfr@canb.auug.org.au: extend this for fsldma] Acked-by: Shannon Nelson <shannon.nelson@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-04-17async_tx: fix multiple dependency submissionDan Williams
Shrink struct dma_async_tx_descriptor and introduce async_tx_channel_switch to properly inject a channel switch interrupt in the descriptor stream. This simplifies the locking model as drivers no longer need to handle dma_async_tx_descriptor.lock. Acked-by: Shannon Nelson <shannon.nelson@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-03-30dma_page_list ->base_address is a userland pointerAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-04dmaengine: fix sparse warningDan Williams
include/linux/dmaengine.h:364:2: warning: returning void-valued expression Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-02-06async_tx: replace 'int_en' with operation preparation flagsDan Williams
Pass a full set of flags to drivers' per-operation 'prep' routines. Currently the only flag passed is DMA_PREP_INTERRUPT. The expectation is that arch-specific async_tx_find_channel() implementations can exploit this capability to find the best channel for an operation. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Shannon Nelson <shannon.nelson@intel.com> Reviewed-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
2008-02-06async_tx: kill tx_set_src and tx_set_dest methodsDan Williams
The tx_set_src and tx_set_dest methods were originally implemented to allow an array of addresses to be passed down from async_xor to the dmaengine driver while minimizing stack overhead. Removing these methods allows drivers to have all transaction parameters available at 'prep' time, saves two function pointers in struct dma_async_tx_descriptor, and reduces the number of indirect branches.. A consequence of moving this data to the 'prep' routine is that multi-source routines like async_xor need temporary storage to convert an array of linear addresses into an array of dma addresses. In order to keep the same stack footprint of the previous implementation the input array is reused as storage for the dma addresses. This requires that sizeof(dma_addr_t) be less than or equal to sizeof(void *). As a consequence CONFIG_DMADEVICES now depends on !CONFIG_HIGHMEM64G. It also requires that drivers be able to make descriptor resources available when the 'prep' routine is polled. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Shannon Nelson <shannon.nelson@intel.com>
2008-02-03include/linux/: Spelling fixesJoe Perches
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>