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path: root/drivers/dma
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2020-02-25dmaengine: ti: edma: Support for interleaved mem to mem transferPeter Ujfalusi
Add basic interleaved support via EDMA. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/20200210094455.3615-1-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: at_xdmac: Fix locking in taskletTudor Ambarus
Tasklets run with all the interrupts enabled. This means that we should replace all the (already present) spin_lock_irqsave() uses in the tasklet with spin_lock_irq() to protect being interrupted by a IRQ which tries to get the same lock (via calls to device_prep_dma_* for example). spin_lock and spin_lock_bh in tasklets are not enough to protect from IRQs, update these to spin_lock_irq(). at_xdmac_advance_work() can be called with all the interrupts enabled (when called from tasklet), or with interrupts disabled (when called from at_xdmac_issue_pending). Move the locking in the callers to be able to use spin_lock_irq() and spin_lock_irqsave() for these cases. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-10-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: at_xdmac: GFP_KERNEL for user that can sleepTudor Ambarus
device_alloc_chan_resources can sleep, use GFP_KERNEL flag. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-9-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: at_xdmac: Drop locking in at_xdmac_alloc_chan_resources()Tudor Ambarus
There is no need for locking in device_alloc_chan_resources(), the DMA core takes care of it by using a dma_list_mutex around the DMA devices. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-8-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: at_xdmac: Drop always true checkTudor Ambarus
The code in cause is already in the else case of 'if (at_xdmac_chan_is_cyclic(atchan))', drop the redundant check. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-7-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: at_hdmac: Fix deadlocksTudor Ambarus
Fix the following deadlocks: 1/ atc_handle_cyclic() and atc_chain_complete() called dmaengine_desc_get_callback_invoke() while wrongly holding the atchan->lock. Clients can set the callback to dmaengine_terminate_sync() which will end up trying to get the same lock, thus a deadlock occurred. 2/ dma_run_dependencies() was called with the atchan->lock held, but the method calls device_issue_pending() which tries to get the same lock, and so a deadlock occurred. The driver must not hold the lock when invoking the callback or when running dependencies. Releasing the spinlock within a called function before calling the callback is not a nice thing to do -> called functions become non-atomic when called within an atomic region. Thus the lock is now taken in the child routines whereever is needed. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-6-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: at_hdmac: Switch atomic allocations to GFP_NOWAITTudor Ambarus
Avoids sleeping without depleting the emergency pool. The rationale being that in most cases a dma device is either offloading an operation that will automatically fallback to software when the descriptor allocation fails, or we can simply poll and wait for the dma device to release some in use descriptors. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-5-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: at_hdmac: Drop description for a not defined parameterTudor Ambarus
Probably a leftover, drop it. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-4-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: at_hdmac: Return err in case the chan is not free at alloc res timeTudor Ambarus
Having a list of descriptors allocated for the channel at device_alloc_chan_resources() time is a sign for bad free usage. Return err and add a debug message in case the channel is not free from a previous use. atchan->descs_allocated becomes useless, get rid of it. More, drop the error message in atc_desc_get() because now it would introduce an extra if statement. The callers of atc_desc_get() already print error messages in case the callee fails, no one is hurt. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-3-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: at_hdmac: Drop locking in at_hdmac_alloc_chan_resources()Tudor Ambarus
There is no need for locking in device_alloc_chan_resources(), the DMA core takes care of it by using a dma_list_mutex around the DMA devices. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-2-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: at_hdmac: Substitute kzalloc with kmallocTudor Ambarus
All members of the structure are initialized below in the function, there is no need to use kzalloc. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-1-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: xilinx_dma: In dma channel probe fix node order dependencyRadhey Shyam Pandey
In overlay application we noticed that dma channel node probe order is inverted i.e s2mm channel is probed first followed by mm2s channel. The reason for this inversion is fdtoverlay utility which uses a function called fdt_add_subnode(*). It stores the subnodes after the properties, this has the effect of inserting the new subnode before any others and the end result is a reversal. Because of this inverted channel probe order, the node probed first is assigned a '0' index instead of Channel ID should be '0' for tx and '1' for rx and dmatest client using the DT convention fails in dma transfer as channel are swapped. To fix above behavior and make channel assignment index independent of probe order, always assign mm2s channel at '0' index and the s2mm channel at IP specific fixed offset derived from the max_channels count. Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com> Link: https://lore.kernel.org/r/1580388865-9960-3-git-send-email-radhey.shyam.pandey@xilinx.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: xilinx_dma: Extend dma_config structure to store max channel countRadhey Shyam Pandey
Extend dma_config structure to store the max channel count. This input is used to populate dma device channel nodes at the fixed offset. It serves as a preparatory patch for removing dma channel DT node order dependency, added in the subsequent commit. Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com> Link: https://lore.kernel.org/r/1580388865-9960-2-git-send-email-radhey.shyam.pandey@xilinx.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: stm32-dma: use vchan_terminate_vdesc() in .terminate_allAmelie Delaunay
To avoid race with vchan_complete, use the race free way to terminate running transfer. Move vdesc->node list_del in stm32_dma_start_transfer instead of in stm32_mdma_chan_complete to avoid another race in vchan_dma_desc_free_list. Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200129153628.29329-9-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: stm32-dma: fix sleeping function called from invalid contextAmelie Delaunay
This patch fixes BUG: sleeping function called from invalid context in stm32_dma_disable_chan function. The goal of this function is to force channel disable if it has not been disabled by hardware. This consists in clearing STM32_DMA_SCR_EN bit and read it as 0 to ensure the channel is well disabled and the last transfer is over. In previous implementation, the waiting loop was based on a do...while (1) with a call to cond_resched to give the scheduler a chance to run a higher priority process. But in some conditions, stm32_dma_disable_chan can be called while preemption is disabled, on a stm32_dma_stop call for example. So cond_resched must not be used. To avoid this, use readl_relaxed_poll_timeout_atomic to poll STM32_DMA_SCR_EN bit cleared. Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200129153628.29329-8-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: stm32-dma: add copy_align constraintAmelie Delaunay
This patch adds copy_align property in accordance with hardware restriction. Signed-off-by: Ludovic Barre <ludovic.barre@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200129153628.29329-7-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: stm32-dma: use dma_set_max_seg_size to set the sg limitAmelie Delaunay
This patch adds dma_set_max_seg_size to define sg dma constraint. This constraint may be taken into account by client to scatter/gather its buffer. Signed-off-by: Ludovic Barre <ludovic.barre@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200129153628.29329-6-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: stm32-dma: enable descriptor_reusePierre-Yves MORDRET
Enable client to resubmit already processed descriptors in order to save descriptor creation time. Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200129153628.29329-5-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: stm32-dma: driver defers probe for resetEtienne Carriere
Change STM32 DMA driver to defer its probe operation when reset controller is expected but has not been probed yet when DMA device is probed. Changes error traces when failing to get a system resource so that it is not printed on failure with deferred probing. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200129153628.29329-4-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: stm32-dma: use reset controller only at probe timeEtienne Carriere
Remove reset controller reference from device instance since it is used only at probe time. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200129153628.29329-3-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-25dmaengine: stm32-dma: add suspend/resume power management supportPierre-Yves MORDRET
Add suspend/resume power management relying on PM Runtime engine. Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200129153628.29329-2-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: imx-sdma: fix context cacheMartin Fuzzey
There is a DMA problem with the serial ports on i.MX6. When the following sequence is performed: 1) Open a port 2) Write some data 3) Close the port 4) Open a *different* port 5) Write some data 6) Close the port The second write sends nothing and the second close hangs. If the first close() is omitted it works. Adding logs to the the UART driver shows that the DMA is being setup but the callback is never invoked for the second write. This used to work in 4.19. Git bisect leads to: ad0d92d: "dmaengine: imx-sdma: refine to load context only once" This commit adds a "context_loaded" flag used to avoid unnecessary context setups. However the flag is only reset in sdma_channel_terminate_work(), which is only invoked in a worker triggered by sdma_terminate_all() IF there is an active descriptor. So, if no active descriptor remains when the channel is terminated, the flag is not reset and, when the channel is later reused the old context is used. Fix the problem by always resetting the flag in sdma_free_chan_resources(). Cc: stable@vger.kernel.org Signed-off-by: Martin Fuzzey <martin.fuzzey@flowbird.group> Fixes: ad0d92d7ba6a ("dmaengine: imx-sdma: refine to load context only once") Reviewed-by: Fabio Estevam <festevam@gmail.com> Link: https://lore.kernel.org/r/1580305274-27274-1-git-send-email-martin.fuzzey@flowbird.group Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: xilinx_dma: Reset DMA channel in dma_terminate_allRadhey Shyam Pandey
Reset DMA channel after stop to ensure that pending transfers and FIFOs in the datapath are flushed or completed. It also cleanup the terminate path and removes stop for the cyclic mode as after the reset stop is not required. This fixes intermittent data verification failure when xilinx dma test the client is stressed and loaded/unloaded multiple times. Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com> Link: https://lore.kernel.org/r/1580283909-32678-1-git-send-email-radhey.shyam.pandey@xilinx.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: stm32-dmamux: driver defers probe for clock and resetEtienne Carriere
Changes STM32 DMAMUX driver to defer its probe operation when reset controller is expected but has not been probed yet. Changes error traces when failing to get a system resource so that it is not printed on failure with deferred probing. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200128094158.20361-5-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: stm32-dmamux: use reset controller only at probe timeEtienne Carriere
Remove reset controller reference from device instance since it is used only at probe time. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200128094158.20361-4-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: stm32-dmamux: fix clock handling in probe sequenceEtienne Carriere
This change ensures the DMAMUX device is reset only once it is clocked and that clock is released in a safe state when probe operation fails. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200128094158.20361-3-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: stm32-dmamux: add suspend/resume power management supportPierre-Yves MORDRET
Add suspend/resume power management relying on PM Runtime engine. Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200128094158.20361-2-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: stm32-mdma: use vchan_terminate_vdesc() in .terminate_allAmelie Delaunay
To avoid race with vchan_complete, use the race free way to terminate running transfer. Move vdesc->node list_del in stm32_mdma_start_transfer instead of in stm32_mdma_xfer_end to avoid another race in vchan_dma_desc_free_list. Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200127085334.13163-7-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: stm32-mdma: enable descriptor_reusePierre-Yves MORDRET
Enable descriptor reuse to allow client to resubmit already processed descriptors in order to save descriptor creation time. Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200127085334.13163-6-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: stm32-mdma: driver defers probe for clock and resetAmelie Delaunay
This patch changes error log when failing to get the clock so that it is not printed on failure with probe deferring. It also defers probe when reset controller is expected but has not been probed yet when MDMA device is probed. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200127085334.13163-5-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: stm32-mdma: disable clock in case of error during probeEtienne Carriere
This patch disables the clock in case of error during probe. The unneeded err_unregister label is renamed err_clk instead. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200127085334.13163-4-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: stm32-mdma: use reset controller only at probe timeEtienne Carriere
Remove reset controller reference from device instance since it is used only at probe time. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200127085334.13163-3-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: stm32-mdma: add suspend/resume power management supportPierre-Yves MORDRET
Add suspend/resume power management relying on PM Runtime engine. Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200127085334.13163-2-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: idxd: wq size configuration needs to check global max sizeDave Jiang
The current size_store() function for idxd sysfs does not check the total wq size. This allows configuration of all wqs with total wq size. Add check to make sure the wq sysfs attribute rejects storing of size over the total wq size. Fixes: c52ca478233c ("dmaengine: idxd: add configuration component of driver") Reported-by: Jerry Chen <jerry.t.chen@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/158213309629.2509.3583411832507185041.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: idxd: sysfs input of wq incorrect wq type should return errorDave Jiang
Currently when inputing an unrecognized wq type, we set the wq type to "none". It really should return error and not change the existing wq type that's in the kernel. Fixes: c52ca478233c ("dmaengine: idxd: add configuration component of driver") Reported-by: Yixin Zhang <yixin.zhang@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/158213304803.2290.13336343633425868211.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-24dmaengine: coh901318: Fix a double lock bug in dma_tc_handle()Dan Carpenter
The caller is already holding the lock so this will deadlock. Fixes: 0b58828c923e ("DMAENGINE: COH 901 318 remove irq counting") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Link: https://lore.kernel.org/r/20200217144050.3i4ymbytogod4ijn@kili.mountain Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmanegine: ioat/dca: Replace zero-length array with flexible-array memberGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Link: https://lore.kernel.org/r/20200214171302.GA20586@embeddedor Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmaengine: tegra210-adma: Replace zero-length array with flexible-array memberGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Link: https://lore.kernel.org/r/20200214171657.GA25663@embeddedor Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmaengine: sprd: Replace zero-length array with flexible-array memberGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Reviewed-by: Baolin Wang <baolin.wang7@gmail.com> Link: https://lore.kernel.org/r/20200214171536.GA24077@embeddedor Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmaengine: sa11x0: Replace zero-length array with flexible-array memberGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Link: https://lore.kernel.org/r/20200214171435.GA22930@embeddedor Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmaengine: idxd: correct reserved token calculationDave Jiang
The calcuation for limit of reserved token did not take into account the change the user wanted vs the current group reserved token. This causes changing of the reserved token to be possible only after we set the value of the reserved token back to 0. Fix calculation so we can set a value that is non zero for reserved token. Fixes: c52ca478233c ("dmaengine: idxd: add configuration component of driver") Reported-by: Jerry Chen <jerry.t.chen@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/158204471889.37789.7749177228265869168.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmaengine: ti: k3-udma: Fix terminated transfer handlingPeter Ujfalusi
When we receive back the descriptor of the terminated transfer the cookie must be marked as completed to make sure that the accounting is correct. In udma_tx_status() the status should be marked as completed if the channel is no longer running (it can only happen if the channel is not yet started for the first time, or after a channel termination). Fixes: 25dcb5dd7b7ce ("dmaengine: ti: New driver for K3 UDMA") Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/20200214091441.27535-7-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmaengine: ti: k3-udma: Use the channel direction in pause/resume functionsPeter Ujfalusi
It should be possible to pause, resume and check the pause state of a channel even if we do not have active transfer. udma_is_chan_paused() can trigger NULL pointer reference in it's current form when the status is checked while uc->desc is NULL. Fixes: 25dcb5dd7b7ce ("dmaengine: ti: New driver for K3 UDMA") Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/20200214091441.27535-6-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmaengine: ti: k3-udma: Use the TR counter helper for slave_sg and cyclicPeter Ujfalusi
Use the generic TR setup function to get the TR counters for both cyclic and slave_sg transfers. This way the period_size for cyclic and sg_dma_len() for slave_sg can be as large as (SZ_64K - 1) * (SZ_64K - 1) and we can handle cases when the length is >SZ_64K and a prime number. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/20200214091441.27535-5-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmaengine: ti: k3-udma: Move the TR counter calculation to helper functionPeter Ujfalusi
Move the TR counter parameter configuration code out from the prep_memcpy callback to a helper function to allow a generic re-usable code for other TR based transfers. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/20200214091441.27535-4-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmaengine: ti: k3-udma: Workaround for RX teardown with stale data in peerPeter Ujfalusi
When a channel is asked to be stopped (teardown) and we do not have active descriptor to receive stale data buffered on the remote side then the teardown will not complete as UDMA needs a descriptor to be able to flush out the DMA pipe. The peer is trying to push the data to UDMA in teardown, but UDMA is pushing back because it has no descriptor which would allow it to drain the data. The workaround is to create 1K 'trashcan' to receive the discarded data and set up descriptors for packet and TR mode channels. When a channel is stopped and there is no active descriptor then a descriptor is pushed to the ring for UDMA before the teardown is initiated. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/20200214091441.27535-3-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-19dmaengine: ti: k3-udma: Use ktime/usleep_range based TX completion checkVignesh Raghavendra
In some cases (McSPI for example) the jiffie and delayed_work based workaround can cause big throughput drop. Switch to use ktime/usleep_range based implementation to be able to sustain speed for PDMA based peripherals. Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/20200214091441.27535-2-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-17dmaengine: sun4i: set the linear_mode properlyVinod Koul
Commit 6ebb827f7aad ("dmaengine: sun4i: use 'linear_mode' in sun4i_dma_prep_dma_cyclic") updated the condition but introduced a semi colon this making this statement have no effect, so add the bitwise OR to fix it" Fixes: 6ebb827f7aad ("dmaengine: sun4i: use 'linear_mode' in sun4i_dma_prep_dma_cyclic") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lore.kernel.org/r/20200214044609.2215861-1-vkoul@kernel.org Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-13dmaengine: ti: dma-crossbar: convert to devm_platform_ioremap_resource()chenqiwu
Use a new API devm_platform_ioremap_resource() to simplify code. Signed-off-by: chenqiwu <chenqiwu@xiaomi.com> Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/1580189746-2864-1-git-send-email-qiwuchen55@gmail.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-13dmaengine: sun4i: use 'linear_mode' in sun4i_dma_prep_dma_cyclicYueHaibing
drivers/dma/sun4i-dma.c: In function sun4i_dma_prep_dma_cyclic: drivers/dma/sun4i-dma.c:672:24: warning: variable linear_mode set but not used [-Wunused-but-set-variable] commit ffc079a4accc ("dmaengine: sun4i: Add support for cyclic requests with dedicated DMA") involved this, explicitly using the value makes the code more readable. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Link: https://lore.kernel.org/r/20200207024445.44600-1-yuehaibing@huawei.com Signed-off-by: Vinod Koul <vkoul@kernel.org>