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* iop-adma: kill debug BUG_ONDan Williams2009-01-06
| | | | | | | | | This BUG_ON caught problems in early development but now it is in the way as it invalidly triggers when trying to remove the module. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* iop-adma: let devm do its job, don't duplicate freeDan Williams2009-01-06
| | | | | | | | No need to free stuff that the devm infrastructure will take care of... Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: kill enum dma_state_clientDan Williams2009-01-06
| | | | | | | | | 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>
* dmaengine: remove 'bigref' infrastructureDan Williams2009-01-06
| | | | | | | | | | 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>
* dmaengine: kill struct dma_client and supporting infrastructureDan Williams2009-01-06
| | | | | | | | | | | | 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>
* dmaengine: replace dma_async_client_register with dmaengine_getDan Williams2009-01-06
| | | | | | | | | | 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>
* atmel-mci: convert to dma_request_channel and down-level dma_slaveDan Williams2009-01-06
| | | | | | | | | | | 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>
* dmatest: convert to dma_request_channelDan Williams2009-01-06
| | | | | | | | | | | | | | | | | 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>
* dmaengine: introduce dma_request_channel and private channelsDan Williams2009-01-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* dmaengine: provide a common 'issue_pending_all' implementationDan Williams2009-01-06
| | | | | | | | | | | | | | | 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>
* dmaengine: centralize channel allocation, introduce dma_find_channelDan Williams2009-01-06
| | | | | | | | | | | | | | | | | | | 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>
* dmaengine: up-level reference counting to the module levelDan Williams2009-01-06
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* dmaengine: remove dependency on async_txDan Williams2009-01-05
| | | | | | | | | | | | | | 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>
* async_xor: dma_map destination DMA_BIDIRECTIONALDan Williams2008-12-08
| | | | | | | | | | | | | | Mapping the destination multiple times is a misuse of the dma-api. Since the destination may be reused as a source, ensure that it is only mapped once and that it is mapped bidirectionally. This appears to add ugliness on the unmap side in that it always reads back the destination address from the descriptor, but gcc can determine that dma_unmap is a nop and not emit the code that calculates its arguments. Cc: <stable@kernel.org> Cc: Saeed Bishara <saeed@marvell.com> Acked-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: protect 'id' from concurrent registrationsDan Williams2008-12-03
| | | | | | | | | | There is a possibility to have two devices registered with the same id. Cc: <stable@kernel.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* ioat: wait for self-test completionDan Williams2008-12-03
| | | | | | | | | | | As part of the ioat_dma self-test it performs a printk from a completion callback. Depending on the system console configuration this output can take longer than a millisecond causing the self-test to fail. Introduce a completion with a generous timeout to mitigate this failure. Cc: <stable@kernel.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers2008-11-11
| | | | | | | Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* iop-adma: use iop_paranoia() for debug BUG_ONsDan Williams2008-11-11
| | | | | | | | Now that the critical read back to flush the next descriptor address is fixed we can downgrade some BUG_ONs that need only be enabled when testing changes to the driver. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* iop-adma: add a dummy read to flush next descriptor updateDan Williams2008-11-11
| | | | | | | | | | | The current dummy read references the wrong address allowing the next descriptor address update to linger in the store buffer and get passed by an 'append' event. This issue was uncovered by the change from strongly-ordered to device memory for the adma registers. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* [3/4] I/OAT: fix async_tx.callback checkingMaciej Sosnowski2008-11-10
| | | | | | | | | async_tx.callback should be checked for the first not the last descriptor in the chain. Cc: <stable@kernel.org> Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [2/4] I/OAT: fix dma_pin_iovec_pages() error handlingMaciej Sosnowski2008-11-10
| | | | | | | | | | | | | Error handling needs to be modified in dma_pin_iovec_pages(). It should return NULL instead of ERR_PTR (pinned_list is checked for NULL in tcp_recvmsg() to determine if iovec pages have been successfully pinned down). In case of error for the first iovec, local_list->nr_iovecs needs to be initialized. Cc: <stable@kernel.org> Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [1/4] I/OAT: fix channel resources free for not allocated channelsMaciej Sosnowski2008-11-10
| | | | | | | | | | | | If the ioatdma driver is loaded but not used it does not allocate descriptors. Before it frees channel resources it should first be sure that they have been previously allocated. Cc: <stable@kernel.org> Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Tested-by: Tom Picard <tom.s.picard@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'i7300_idle' into releaseLen Brown2008-10-25
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| * i7300_idle: Fix compile warning CONFIG_I7300_IDLE_IOAT_CHANNEL not definedVenki Pallipadi2008-10-24
| | | | | | | | | | | | | | | | | | | | When I7300_idle driver is not configured, there is a compile time warning about IDLE_IOAT_CHANNEL not defined. Fix it. Reported-by: Suresh Siddha <suresh.b.siddha@intel.com> Reported-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
| * i7300_idle: Disable ioat channel only on platforms where ile driver can loadVenki Pallipadi2008-10-24
| | | | | | | | | | | | | | | | | | Based on input from Andi Kleen: share the platform detection code with ioat_dma and disable the channel in dma engine only for specific platforms. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
* | Merge branch 'linus' into testLen Brown2008-10-23
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | Conflicts: MAINTAINERS arch/x86/kernel/acpi/boot.c arch/x86/kernel/acpi/sleep.c drivers/acpi/Kconfig drivers/pnp/Makefile drivers/pnp/quirks.c Signed-off-by: Len Brown <len.brown@intel.com>
| * Merge branch 'next' of ↵Linus Torvalds2008-10-20
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: fsldma: allow Freescale Elo DMA driver to be compiled as a module fsldma: remove internal self-test from Freescale Elo DMA driver drivers/dma/dmatest.c: switch a GFP_ATOMIC to GFP_KERNEL dmatest: properly handle duplicate DMA channels drivers/dma/ioat_dma.c: drop code after return async_tx: make async_tx_run_dependencies() easier to read
| | * fsldma: allow Freescale Elo DMA driver to be compiled as a moduleTimur Tabi2008-09-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Modify the Freescale Elo / Elo Plus DMA driver so that it can be compiled as a module. The primary change is to stop treating the DMA controller as a bus, and the DMA channels as devices on the bus. This is because the Open Firmware (OF) kernel code does not allow busses to be removed, so although we can call of_platform_bus_probe() to probe the DMA channels, there is no of_platform_bus_remove(). Instead, the DMA channels are manually probed, similar to what fsl_elbc_nand.c does. Cc: Scott Wood <scottwood@freescale.com> Acked-by: Li Yang <leoli@freescale.com> Signed-off-by: Timur Tabi <timur@freescale.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| | * fsldma: remove internal self-test from Freescale Elo DMA driverTimur Tabi2008-09-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Freescale Elo DMA driver runs an internal self-test before registering the channels with the DMA engine. This self-test has a fundemental flaw in that it calls the DMA engine's callback functions directly before the registration. However, the registration initializes some variables that the callback functions uses, namely the device struct. The code works today because there are two device structs: the one created by the DMA engine, and one created by the Open Firmware (OF) subsystem. The self-test currently uses the device struct created by OF. However, in the future, some of the device structs created by OF will be eliminated. This means that the self-test will only have access to the device struct created by the DMA engine. But this device struct isn't initialized when the self-test runs, and this causes a kernel panic. Since there is already a DMA test module (dmatest), the internal self-test code is not useful anyway. It is extremely unlikely that the test will fail in normal usage. It may have been helpful during development, but not any more. Cc: Kumar Gala <galak@kernel.crashing.org> Cc: Li Yang <leoli@freescale.com> Cc: Scott Wood <scottwood@freescale.com> Signed-off-by: Timur Tabi <timur@freescale.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| | * drivers/dma/dmatest.c: switch a GFP_ATOMIC to GFP_KERNELAndrew Morton2008-09-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | It was needlessly using the unreliable GFP_ATOMIC. Cc: Timur Tabi <timur@freescale.com> Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| | * dmatest: properly handle duplicate DMA channelsTimur Tabi2008-09-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update the the dmatest driver so that it handles duplicate DMA channels properly. When a DMA client is notified of an available DMA channel, it must check if it has already allocated resources for that channel. If so, it should return DMA_DUP. This can happen, for example, if a DMA driver calls dma_async_device_register() more than once. Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Timur Tabi <timur@freescale.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| | * drivers/dma/ioat_dma.c: drop code after returnJulia Lawall2008-09-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | The break after the return serves no purpose. Signed-off-by: Julia Lawall <julia@diku.dk> Reviewed-by: Richard Genoud <richard.genoud@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | | i7300_idle driver v1.55Andy Henroid2008-10-21
|/ / | | | | | | | | | | | | | | | | | | | | | | | | The Intel 7300 Memory Controller supports dynamic throttling of memory which can be used to save power when system is idle. This driver does the memory throttling when all CPUs are idle on such a system. Refer to "Intel 7300 Memory Controller Hub (MCH)" datasheet for the config space description. Signed-off-by: Andy Henroid <andrew.d.henroid@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
* / dw_dmac: fix copy/paste bug in taskletHaavard Skinnemoen2008-10-03
|/ | | | | | | | | | | The tasklet checks RAW.BLOCK twice, and does not check RAW.XFER. This is obviously wrong, and could theoretically cause the driver to hang. Reported-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-rmk' of git://git.marvell.com/orionRussell King2008-08-09
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| * [ARM] Move include/asm-arm/plat-orion to arch/arm/plat-orion/include/platLennert Buytenhek2008-08-09
| | | | | | | | | | | | | | This patch performs the equivalent include directory shuffle for plat-orion, and fixes up all users. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
* | Merge branch 'for-linus-merged' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds2008-08-08
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-linus-merged' of master.kernel.org:/home/rmk/linux-2.6-arm: [ARM] 5177/1: arm/mach-sa1100/Makefile: remove CONFIG_SA1100_USB [ARM] 5166/1: magician: add MAINTAINERS entry [ARM] fix pnx4008 build errors [ARM] Fix SMP booting with non-zero PHYS_OFFSET [ARM] 5185/1: Fix spi num_chipselect for lubbock [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach [ARM] Add support for arch/arm/mach-*/include and arch/arm/plat-*/include [ARM] Remove asm/hardware.h, use asm/arch/hardware.h instead [ARM] Eliminate useless includes of asm/mach-types.h [ARM] Fix circular include dependency with IRQ headers avr32: Use <mach/foo.h> instead of <asm/arch/foo.h> avr32: Introduce arch/avr32/mach-*/include/mach avr32: Move include/asm-avr32 to arch/avr32/include/asm [ARM] sa1100_wdt: use reset_status to remember watchdog reset status [ARM] pxa: introduce reset_status and clear_reset_status for driver's usage [ARM] pxa: introduce reset.h for reset specific header information
| * [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/machRussell King2008-08-07
| | | | | | | | | | | | This just leaves include/asm-arm/plat-* to deal with. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | list.h: Add list_splice_tail() and list_splice_tail_init()Luis R. Rodriguez2008-08-07
|/ | | | | | | | | | | If you are using linked lists for queues list_splice() will not do what you would expect even if you use the elements passed reversed. We need to handle these differently. We add list_splice_tail() and list_splice_tail_init(). Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* I/OAT: I/OAT version 3.0 supportMaciej Sosnowski2008-07-22
| | | | | | | | | | | | This patch adds to ioatdma and dca modules support for Intel I/OAT DMA engine ver.3 (aka CB3 device). The main features of I/OAT ver.3 are: * 8 single channel DMA devices (8 channels total) * 8 DCA providers, each can accept 2 requesters * 8-bit TAG values and 32-bit extended APIC IDs Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* I/OAT: tcp_dma_copybreak default value dependent on I/OAT versionMaciej Sosnowski2008-07-22
| | | | | | | | | | | I/OAT DMA performance tuning showed different optimal values of tcp_dma_copybreak for different I/OAT versions (4096 for 1.2 and 2048 for 2.0). This patch lets ioatdma driver set tcp_dma_copybreak value according to these results. [dan.j.williams@intel.com: remove some ifdefs] Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* I/OAT: Add watchdog/reset functionality to ioatdmaMaciej Sosnowski2008-07-22
| | | | | | | | | | | | Due to occasional DMA channel hangs observed for I/OAT versions 1.2 and 2.0 a watchdog has been introduced to check every 2 seconds if all channels progress normally. If stuck channel is detected, driver resets it. The reset is done in two parts. The second part is scheduled by the first one to reinitialize the channel after the restart. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* iop_adma: document how to calculate the minimum descriptor pool sizeDan Williams2008-07-17
| | | | Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* iop_adma: directly reclaim descriptors on allocation failureDan Williams2008-07-17
| | | | | | | | Force callers that trigger an "out of descriptors" condition to run the cleanup loop directly. Alleviates the requirement to have soft-irqs enabled when polling for a descriptor in async_xor. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: Driver for the Synopsys DesignWare DMA controllerHaavard Skinnemoen2008-07-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a driver for the Synopsys DesignWare DMA controller (aka DMACA on AVR32 systems.) This DMA controller can be found integrated on the AT32AP7000 chip and is primarily meant for peripheral DMA transfer, but can also be used for memory-to-memory transfers. This patch is based on a driver from David Brownell which was based on an older version of the DMA Engine framework. It also implements the proposed extensions to the DMA Engine API for slave DMA operations. The dmatest client shows no problems, but there may still be room for improvement performance-wise. DMA slave transfer performance is definitely "good enough"; reading 100 MiB from an SD card running at ~20 MHz yields ~7.2 MiB/s average transfer rate. Full documentation for this controller can be found in the Synopsys DW AHB DMAC Databook: http://www.synopsys.com/designware/docs/iip/DW_ahb_dmac/latest/doc/dw_ahb_dmac_db.pdf The controller has lots of implementation options, so it's usually a good idea to check the data sheet of the chip it's intergrated on as well. The AT32AP7000 data sheet can be found here: http://www.atmel.com/dyn/products/datasheets.asp?family_id=682 Changes since v4: * Use client_count instead of dma_chan_is_in_use() * Add missing include * Unmap buffers unless client told us not to Changes since v3: * Update to latest DMA engine and DMA slave APIs * Embed the hw descriptor into the sw descriptor * Clean up and update MODULE_DESCRIPTION, copyright date, etc. Changes since v2: * Dequeue all pending transfers in terminate_all() * Rename dw_dmac.h -> dw_dmac_regs.h * Define and use controller-specific dma_slave data * Fix up a few outdated comments * Define hardware registers as structs (doesn't generate better code, unfortunately, but it looks nicer.) * Get number of channels from platform_data instead of hardcoding it based on CONFIG_WHATEVER_CPU. * Give slave clients exclusive access to the channel 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>
* dmaengine: Add slave DMA interfaceHaavard Skinnemoen2008-07-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* dmaengine: add DMA_COMPL_SKIP_{SRC,DEST}_UNMAP flags to control dma unmapDan Williams2008-07-08
| | | | | | | | | | | | | | 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>
* dmaengine: Add dma_client parameter to device_alloc_chan_resourcesHaavard Skinnemoen2008-07-08
| | | | | | | | | | | | | | | | 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>
* dmatest: Simple DMA memcpy test clientHaavard Skinnemoen2008-07-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This client tests DMA memcpy using various lengths and various offsets into the source and destination buffers. It will initialize both buffers with a repeatable pattern and verify that the DMA engine copies the requested region and nothing more. It will also verify that the bytes aren't swapped around, and that the source buffer isn't modified. The dmatest module can be configured to test a specific device, a specific channel. It can also test multiple channels at the same time, and it can start multiple threads competing for the same channel. Changes since v2: * Support testing multiple channels at the same time * Support testing with multiple threads competing for the same channel * Use counting test patterns in order to catch byte ordering issues Changes since v1: * Remove extra dashes around "help" * Remove "default n" from Kconfig * Turn TEST_BUF_SIZE into a module parameter * Return DMA_NAK instead of DMA_DUP * Print unhandled events * Support testing specific channels and devices * Move to the end of the Makefile Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: DMA engine driver for Marvell XOR engineSaeed Bishara2008-07-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | The XOR engine found in Marvell's SoCs and system controllers provides XOR and DMA operation, iSCSI CRC32C calculation, memory initialization, and memory ECC error cleanup operation support. This driver implements the DMA engine API and supports the following capabilities: - memcpy - xor - memset The XOR engine can be used by DMA engine clients implemented in the kernel, one of those clients is the RAID module. In that case, I observed 20% improvement in the raid5 write throughput, and 40% decrease in the CPU utilization when doing array construction, those results obtained on an 5182 running at 500Mhz. When enabling the NET DMA client, the performance decreased, so meanwhile it is recommended to keep this client off. Signed-off-by: Saeed Bishara <saeed@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Signed-off-by: Nicolas Pitre <nico@marvell.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>