blackbird-op-linux/drivers/dma/sf-pdma, branch master

dmaengine: virt-dma: Add missing locking

2019-12-26T04:34:18+00:00

Originally freeing descriptors was split into a locked and an unlocked part. The locked part in vchan_get_all_descriptors() collected all descriptors on a separate list_head. This was done to allow iterating over that new list in vchan_dma_desc_free_list() without a lock held. This became broken in 13bb26ae8850 ("dmaengine: virt-dma: don't always free descriptor upon completion"). With this commit vchan_dma_desc_free_list() no longer exclusively operates on the separate list, but starts to put descriptors which can be reused back on &vc->desc_allocated. This list operation should have been locked, but wasn't. In the mean time drivers started to call vchan_dma_desc_free_list() with their lock held so that we now have the situation that vchan_dma_desc_free_list() is called locked from some drivers and unlocked from others. To clean this up we have to do two things: 1. Add missing locking in vchan_dma_desc_free_list() 2. Make sure drivers call vchan_dma_desc_free_list() unlocked This needs to be done atomically, so in this patch the locking is added and all drivers are fixed. Signed-off-by: Sascha Hauer Reviewed-by: Peter Ujfalusi Tested-by: Peter Ujfalusi Reviewed-by: Green Wan Tested-by: Green Wan Link: https://lore.kernel.org/r/20191216105328.15198-3-s.hauer@pengutronix.de Signed-off-by: Vinod Koul

dmaengine: sf-pdma: move macro to header file

2019-11-22T05:45:28+00:00

The place where the macro, SF_PDMA_REG_BASE(), is cause kernel-doc using wrong function declaration. Move it to header file. Signed-off-by: Green Wan Link: https://lore.kernel.org/r/20191118143554.16129-2-green.wan@sifive.com Signed-off-by: Vinod Koul

dmaengine: sf-pdma: replace /** with /* for non-function comment

2019-11-22T05:45:28+00:00

There are several comments starting from "/**" but not for function comment purpose. It causes kernel-doc parsing wrong string. Replace "/**" with "/*" to fix them. Signed-off-by: Green Wan Link: https://lore.kernel.org/r/20191118143554.16129-1-green.wan@sifive.com Signed-off-by: Vinod Koul

dmaengine: sf-pdma: add platform DMA support for HiFive Unleashed A00

2019-11-14T07:10:46+00:00

Add PDMA driver, sf-pdma, to enable DMA engine on HiFive Unleashed Rev A00 board. - Implement dmaengine APIs, support MEM_TO_MEM async copy. - Tested by DMA Test client - Supports 4 channels DMA, each channel has 1 done and 1 err interrupt connected to platform-level interrupt controller (PLIC). - Depends on DMA_ENGINE and DMA_VIRTUAL_CHANNELS The datasheet is here: https://static.dev.sifive.com/FU540-C000-v1.0.pdf Follow the DMAengine controller doc, "./Documentation/driver-api/dmaengine/provider.rst" to implement DMA engine. And use the dma test client in doc, "./Documentation/driver-api/dmaengine/dmatest.rst", to test. Each DMA channel has separate HW regs and support done and error ISRs. 4 channels share 1 done and 1 err ISRs. There's no expander/arbitrator in DMA HW. ------ ------ | |--< done 23 >--|ch 0| | |--< err 24 >--| | (dma0chan0) | | ------ | | ------ | |--< done 25 >--|ch 1| | |--< err 26 >--| | (dma0chan1) |PLIC| ------ | | ------ | |--< done 27 >--|ch 2| | |--< err 28 >--| | (dma0chan2) | | ------ | | ------ | |--< done 29 >--|ch 3| | |--< err 30 >--| | (dma0chan3) ------ ------ Signed-off-by: Green Wan Link: https://lore.kernel.org/r/20191107084955.7580-4-green.wan@sifive.com Signed-off-by: Vinod Koul