Hi, Changes sicne v4: - Move the dmaengine_debugfs_init() from late_initcall to be called from dma_bus_init to avoid races due to probe orders of drivers. - Separate patch to create DMA driver directories for debugfs Changes since v3: - Create a directory for dmaengine and name the initial file as summary - Function to get the debugfs root for DMA drivers if they want to place files - Custom dbg_summary_show implementation for k3-udma Changes since v2: - Use dma_chan_name() for printing the channel's name Changes since v1: - Use much more simplified fops for the debugfs file (via DEFINE_SHOW_ATTRIBUTE) - do not allow modification to dma_device_list while the debugfs file is read - rename the slave_name to dbg_client_name (it is only for debugging) - print information about dma_router if it is used by the channel - Formating of the output slightly changed The basic debugfs file (/sys/kernel/debug/dmaengine/summary) can be used to query basic information about the DMAengine usage (am654-evm): # cat /sys/kernel/debug/dmaengine/summary dma0 (285c0000.dma-controller): number of channels: 96 dma1 (31150000.dma-controller): number of channels: 267 dma1chan0 | 2b00000.mcasp:tx dma1chan1 | 2b00000.mcasp:rx dma1chan2 | in-use dma1chan3 | in-use dma1chan4 | in-use dma1chan5 | in-use Drivers can implement custom dbg_summary_show to add extended information via the summary file, like with the second patch for k3-udma (j721e-evm): # cat /sys/kernel/debug/dmaengine/summary dma0 (285c0000.dma-controller): number of channels: 24 dma1 (31150000.dma-controller): number of channels: 84 dma1chan0 | 2b00000.mcasp:tx (MEM_TO_DEV, tchan16 [0x1010 -> 0xc400], PDMA[ ACC32 BURST ], TR mode) dma1chan1 | 2b00000.mcasp:rx (DEV_TO_MEM, rchan16 [0x4400 -> 0x9010], PDMA[ ACC32 BURST ], TR mode) dma1chan2 | 2ba0000.mcasp:tx (MEM_TO_DEV, tchan17 [0x1011 -> 0xc507], PDMA[ ACC32 BURST ], TR mode) dma1chan3 | 2ba0000.mcasp:rx (DEV_TO_MEM, rchan17 [0x4507 -> 0x9011], PDMA[ ACC32 BURST ], TR mode) dma1chan4 | in-use (MEM_TO_MEM, chan0 pair [0x1000 -> 0x9000], PSI-L Native, TR mode) dma1chan5 | in-use (MEM_TO_MEM, chan1 pair [0x1001 -> 0x9001], PSI-L Native, TR mode) dma1chan6 | in-use (MEM_TO_MEM, chan4 pair [0x1004 -> 0x9004], PSI-L Native, TR mode) dma1chan7 | in-use (MEM_TO_MEM, chan5 pair [0x1005 -> 0x9005], PSI-L Native, TR mode) With the last patch the debugfs looks like this: # ls -al /sys/kernel/debug/dmaengine/ total 0 drwxr-xr-x 4 root root 0 Jan 1 02:00 . drwx------ 29 root root 0 Jan 1 02:00 .. drwxr-xr-x 2 root root 0 Jan 1 02:00 285c0000.dma-controller drwxr-xr-x 2 root root 0 Jan 1 02:00 31150000.dma-controller -r--r--r-- 1 root root 0 Jan 1 02:00 summary Regards, Peter --- Peter Ujfalusi (3): dmaengine: Add basic debugfs support dmaengine: ti: k3-udma: Implement custom dbg_summary_show for debugfs dmaengine: Create debug directories for DMA devices drivers/dma/dmaengine.c | 102 +++++++++++++++++++++++++++++++++++++- drivers/dma/dmaengine.h | 16 ++++++ drivers/dma/ti/k3-udma.c | 63 +++++++++++++++++++++++ include/linux/dmaengine.h | 14 +++++- 4 files changed, 193 insertions(+), 2 deletions(-) -- Peter Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
