pm24.git/drivers/dma/sf-pdma, branch master

dmaengine: fix typo in the comment

2024-10-21T17:37:08Z

Correctly spelled comments make it easier for the reader to understand the code. Replace 'enngine' with 'engine' in the comment & replace 'trascatioin' with 'transaction' in the comment & replace 'descripter' with 'descriptor' in the comment & replace 'descritpor' with 'descriptor' in the comment & replace 'rgisters' with 'registers' in the comment. Signed-off-by: Yan Zhen Acked-by: Palmer Dabbelt Link: https://lore.kernel.org/r/20240918034114.860132-1-yanzhen@vivo.com Signed-off-by: Vinod Koul

dmaengine: Switch back to struct platform_driver::remove()

2024-10-14T18:20:34Z

After commit 0edb555a65d1 ("platform: Make platform_driver::remove() return void") .remove() is (again) the right callback to implement for platform drivers. Convert all platform drivers below drivers/dma after the previous conversion commits apart from the wireless drivers to use .remove(), with the eventual goal to drop struct platform_driver::remove_new(). As .remove() and .remove_new() have the same prototypes, conversion is done by just changing the structure member name in the driver initializer. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20241004062227.187726-2-u.kleine-koenig@baylibre.com Signed-off-by: Vinod Koul

dmaengine: sf-pdma: add mpfs-pdma compatible name

2023-12-11T11:03:22Z

Sifive platform dma (sf-pdma) has both in-order and out-of-order configurations but sf-pdam driver configured to do in-order DMA transfers, with out-of-order configuration got better throughput in the PolarFire SoC platform. Add a PolarFire SoC specific compatible and code to support for out-of-order dma transfers Reviewed-by: Emil Renner Berthing Signed-off-by: Shravan Chippa Link: https://lore.kernel.org/r/20231208103856.3732998-4-shravan.chippa@microchip.com Signed-off-by: Vinod Koul

dmaengine: sf-pdma: Support of_dma_controller_register()

2023-12-11T11:03:22Z

Update sf-pdma driver to adopt generic DMA device tree bindings. It calls of_dma_controller_register() with of_dma_xlate_by_chan_id to get the generic DMA device tree helper support and the DMA clients can look up the sf-pdma controller using standard APIs. Signed-off-by: Shravan Chippa Link: https://lore.kernel.org/r/20231208103856.3732998-2-shravan.chippa@microchip.com Signed-off-by: Vinod Koul

dmaengine: sf-pdma: Annotate struct sf_pdma with __counted_by

2023-09-28T11:12:14Z

Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct sf_pdma. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Vinod Koul Cc: Green Wan Cc: dmaengine@vger.kernel.org Signed-off-by: Kees Cook Reviewed-by: "Gustavo A. R. Silva" Link: https://lore.kernel.org/r/20230817235859.49846-9-keescook@chromium.org Signed-off-by: Vinod Koul

dmaengine: sf-pdma: sf-pdma: Convert to platform remove callback returning void

2023-09-28T07:40:54Z

The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is ignored (apart from emitting a warning) and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new() which already returns void. Eventually after all drivers are converted, .remove_new() is renamed to .remove(). Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20230919133207.1400430-39-u.kleine-koenig@pengutronix.de Signed-off-by: Vinod Koul

dmaengine: sf-pdma: pdma_desc memory leak fix

2023-02-16T13:15:48Z

Commit b2cc5c465c2c ("dmaengine: sf-pdma: Add multithread support for a DMA channel") changed sf_pdma_prep_dma_memcpy() to unconditionally allocate a new sf_pdma_desc each time it is called. The driver previously recycled descs, by checking the in_use flag, only allocating additional descs if the existing one was in use. This logic was removed in commit b2cc5c465c2c ("dmaengine: sf-pdma: Add multithread support for a DMA channel"), but sf_pdma_free_desc() was not changed to handle the new behaviour. As a result, each time sf_pdma_prep_dma_memcpy() is called, the previous descriptor is leaked, over time leading to memory starvation: unreferenced object 0xffffffe008447300 (size 192): comm "irq/39-mchp_dsc", pid 343, jiffies 4294906910 (age 981.200s) hex dump (first 32 bytes): 00 00 00 ff 00 00 00 00 b8 c1 00 00 00 00 00 00 ................ 00 00 70 08 10 00 00 00 00 00 00 c0 00 00 00 00 ..p............. backtrace: [<00000000064a04f4>] kmemleak_alloc+0x1e/0x28 [<00000000018927a7>] kmem_cache_alloc+0x11e/0x178 [<000000002aea8d16>] sf_pdma_prep_dma_memcpy+0x40/0x112 Add the missing kfree() to sf_pdma_free_desc(), and remove the redundant in_use flag. Fixes: b2cc5c465c2c ("dmaengine: sf-pdma: Add multithread support for a DMA channel") Signed-off-by: Shravan Chippa Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20230120100623.3530634-1-shravan.chippa@microchip.com Signed-off-by: Vinod Koul

dmaengine: drivers: Use devm_platform_ioremap_resource()

2023-01-18T16:46:47Z

platform_get_resource() and devm_ioremap_resource() are wrapped up in the devm_platform_ioremap_resource() helper. Use the helper and get rid of the local variable for struct resource *. We now have a function call less. Signed-off-by: Tudor Ambarus Acked-by: Jernej Skrabec Acked-by: Peter Ujfalusi Link: https://lore.kernel.org/r/20221110152528.7821-1-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul

dmaengine: sf-pdma:Remove the print function dev_err()

2022-09-05T06:20:38Z

>From the coccinelle check: ./drivers/dma/sf-pdma/sf-pdma.c Error:line 409 is redundant because platform_get_irq() already prints an error ./drivers/dma/sf-pdma/sf-pdma.c Error:line 424 is redundant because platform_get_irq() already prints an error So,remove the unnecessary print function dev_err() Reported-by: Zeal Robot Signed-off-by: ye xingchen Link: https://lore.kernel.org/r/20220810062532.13425-1-ye.xingchen@zte.com.cn Signed-off-by: Vinod Koul

dmaengine: sf-pdma: Add multithread support for a DMA channel

2022-07-06T12:40:34Z

When we get a DMA channel and try to use it in multiple threads it will cause oops and hanging the system. % echo 64 > /sys/module/dmatest/parameters/threads_per_chan % echo 10000 > /sys/module/dmatest/parameters/iterations % echo 1 > /sys/module/dmatest/parameters/run [ 89.480664] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a0 [ 89.488725] Oops [#1] [ 89.494708] CPU: 2 PID: 1008 Comm: dma0chan0-copy0 Not tainted 5.17.0-rc5 [ 89.509385] epc : vchan_find_desc+0x32/0x46 [ 89.513553] ra : sf_pdma_tx_status+0xca/0xd6 This happens because of data race. Each thread rewrite channels's descriptor as soon as device_prep_dma_memcpy() is called. It leads to the situation when the driver thinks that it uses right descriptor that actually is freed or substituted for other one. With current fixes a descriptor changes its value only when it has been used. A new descriptor is acquired from vc->desc_issued queue that is already filled with descriptors that are ready to be sent. Threads have no direct access to DMA channel descriptor. Now it is just possible to queue a descriptor for further processing. Fixes: 6973886ad58e ("dmaengine: sf-pdma: add platform DMA support for HiFive Unleashed A00") Signed-off-by: Viacheslav Mitrofanov Link: https://lore.kernel.org/r/20220701082942.12835-1-v.v.mitrofanov@yadro.com Signed-off-by: Vinod Koul