kernel.git/drivers/dma/pl330.c, branch linux-4.2.y

dmaengine: pl330: Really fix choppy sound because of wrong residue calculation

2015-07-07T04:00:16Z

When pl330 driver was used during sound playback, after some time or after a number of plays the sound became choppy or totally noisy. For example on Odroid XU3 board the first four executions of aplay with small WAVE worked fine, but fifth was unrecognizable with errors: $ aplay /usr/share/sounds/alsa/Front_Right.wava underrun!!! (at least 0.095 ms long) Issue was caused by wrong residue reported by pl330 driver to pcm_dmaengine for its cyclic dma transfers. The pl330_tx_status(), residue reporting function, used a "last" flag in a descriptor to indicate that there is no more data to send. The pl330_tx_submit() iterated over descriptors trying to remove this flag from them and then mark last descriptor as "last". However when iterating it actually removed the flag not from descriptors but always from last of it (and then reset it). Thus effectively once some descriptor was marked as last, then it stayed like this forever causing residue to be reported too low. Signed-off-by: Krzysztof Kozlowski Fixes: aee4d1fac887 ("dmaengine: pl330: improve pl330_tx_status() function") Cc: Reported-by: gabriel@unseen.is Suggested-by: Marek Szyprowski Tested-by: Lars-Peter Clausen Signed-off-by: Vinod Koul

dmaengine: pl330: Fix overflow when reporting residue in memcpy

2015-07-07T03:57:53Z

During memcpy operations the residue was always set to an u32 overflowed value. In pl330_tx_status() function number of currently transferred bytes was subtracted from internal "bytes_requested" field. However this "bytes_requested" was not initialized at start to length of memcpy buffer so transferred bytes were subtracted from 0 causing overflow. Signed-off-by: Krzysztof Kozlowski Cc: Fixes: aee4d1fac887 ("dmaengine: pl330: improve pl330_tx_status() function") Signed-off-by: Vinod Koul

Merge tag 'dmaengine-4.2-rc1' of git://git.infradead.org/users/vkoul/slave-dma

2015-06-29T16:44:45Z

Pull dmaengine updates from Vinod Koul: "This time we have support for few new devices, few new features and odd fixes spread thru the subsystem. New devices added: - support for CSRatlas7 dma controller - Allwinner H3(sun8i) controller - TI DMA crossbar driver on DRA7x - new pxa driver New features added: - memset support is bought back now that we have a user in xdmac controller - interleaved transfers support different source and destination strides - supporting DMA routers and configuration thru DT - support for reusing descriptors - xdmac memset and interleaved transfer support - hdmac support for interleaved transfers - omap-dma support for memcpy Others: - Constify platform_device_id - mv_xor fixes and improvements" * tag 'dmaengine-4.2-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (46 commits) dmaengine: xgene: fix file permission dmaengine: fsl-edma: clear pending interrupts on initialization dmaengine: xdmac: Add memset support Documentation: dmaengine: document DMA_CTRL_ACK dmaengine: virt-dma: don't always free descriptor upon completion dmaengine: Revert "drivers/dma: remove unused support for MEMSET operations" dmaengine: hdmac: Implement interleaved transfers dmaengine: Move icg helpers to global header dmaengine: mv_xor: improve descriptors list handling and reduce locking dmaengine: mv_xor: Enlarge descriptor pool size dmaengine: mv_xor: add support for a38x command in descriptor mode dmaengine: mv_xor: Rename function for consistent naming dmaengine: mv_xor: bug fix for racing condition in descriptors cleanup dmaengine: pl330: fix wording in mcbufsz message dmaengine: sirf: add CSRatlas7 SoC support dmaengine: xgene-dma: Fix "incorrect type in assignement" warnings dmaengine: fix kernel-doc documentation dmaengine: pxa_dma: add support for legacy transition dmaengine: pxa_dma: add debug information dmaengine: pxa: add pxa dmaengine driver ...

dmaengine: pl330: fix wording in mcbufsz message

2015-06-08T11:04:38Z

The kernel is not trying to increase mcbufsz. It suggests you should try doing so. Also print the calculated required size of mcbufsz. Signed-off-by: Michal Suchanek Reviewed-by: Krzysztof Kozlowski Signed-off-by: Vinod Koul

dmaengine: pl330: Initialize pl330 for pl330_prep_dma_memcpy after NULL check of pch

2015-05-25T17:06:08Z

Currently pch pointer is already dereferenced before NULL check and thus we are getting below warning: warn: variable dereferenced before check 'pch' So initialize struct pl330_dmac *pl330 after NULL check of dma_pl330_chan *pch. Signed-off-by: Maninder Singh Reviewed-by: Vaneet Narang Signed-off-by: Vinod Koul

dmaengine: pl330: Fix hang on dmaengine_terminate_all on certain boards

2015-05-22T12:31:03Z

The pl330 device could hang infinitely on certain boards when DMA channels are terminated. It was caused by lack of runtime resume when executing pl330_terminate_all() which calls the _stop() function. _stop() accesses device register and can loop infinitely while checking for device state. The hang was confirmed by Dinh Nguyen on Altera SOCFPGA Cyclone V board during boot. It can be also triggered with: $ echo 1 > /sys/module/dmatest/parameters/iterations $ echo dma1chan0 > /sys/module/dmatest/parameters/channel $ echo 1 > /sys/module/dmatest/parameters/run $ sleep 1 $ cat /sys/module/dmatest/parameters/run Reported-by: Dinh Nguyen Signed-off-by: Krzysztof Kozlowski Fixes: ae43b3289186 ("ARM: 8202/1: dmaengine: pl330: Add runtime Power Management support v12") Cc: Tested-by: Dinh Nguyen Signed-off-by: Vinod Koul

dmaengine: pl330: fix return status on pending transfers

2015-03-18T17:11:49Z

The pl330_tx_status() function returns the desc->status if the dma_cookie_status() call does indicate the cookie completed, however the desc->status is not look directly compatible. Sparse throws the following warning: pl330.c:2262:35: warning: mixing different enum types pl330.c:2262:35: int enum desc_status versus pl330.c:2262:35: int enum dma_status Attempt to fix this by adding a switch statement to turn the desc->status into a dma_status. Note, this has only been tested with the dmatest suite. Signed-off-by: Ben Dooks -- Vinod Koul Dan Williams DMA List Maxime Ripard Jassi Brar Liviu Dudau Linux ARM Kernel Signed-off-by: Vinod Koul

dmaengine: pl330: make unexported functions static

2015-03-18T17:11:49Z

Whilst running sparse on pl330 driver it was noticed there are two functions that are not static but not exported to any other users in the kernel. Fix the following warnings by making 'pl330_pause' and the 'pl330_get_current_xferred_count' static: pl330.c:2165:5: warning: symbol 'pl330_pause' was not declared. Should it be static? pl330.c:2206:5: warning: symbol 'pl330_get_current_xferred_count' was not declared. Should it be static? Signed-off-by: Ben Dooks -- Vinod Koul Dan Williams DMA List Maxime Ripard Jassi Brar Liviu Dudau Linux ARM Kernel Signed-off-by: Vinod Koul

dmaengine: pl330: fix issues with big-endian armv7

2015-03-18T17:11:48Z

When running Xilinx Zynq in big-endian mode the pl330 driver fails to pass the dmatest suite. To fix this, ensure all non byte values are written in little endian. As a note, the documentation does not mention if it will do big-endian descriptor fetches, only that it will swap the data in flight. Signed-off-by: Ben Dooks -- Vinod Koul Dan Williams DMA List Maxime Ripard Jassi Brar Liviu Dudau Linux ARM Kernel Signed-off-by: Vinod Koul

dmaengine: pl330: add DMA_PAUSE feature

2015-02-16T04:03:36Z

DMA_PAUSE command is used for halting DMA transfer on chosen channel. It can be useful when we want to safely read residue before terminating all requests on channel. Otherwise there can be situation when some data is transferred before channel termination but after reading residue, which obviously results with data loss. To avoid this situation we can pause channel, read residue and then terminate all requests. This scenario is common, for example, in serial port drivers. Signed-off-by: Robert Baldyga Signed-off-by: Vinod Koul