Hello, I’ve been reverse engineering Sony SxS memory cards, which are simple PCIe based block devices. I am able to read successfully from the device with DMA memory allocated using pci_alloc_consistent and memcpying to the buffer the block device layer provides.
But if I use the dma_addr_t provided by the block device DMA layer, I get a soft lockup. Is there something special about the dma_addr_t that comes from the block layer? Is there anything I need to do to it before passing it to the hardware. The device’s block size is 2048, the block layer reads two blocks at a time. Memcpy code is here: https://github.com/kierank/sxs-linux/blob/master/sxs.c#L98 DMA code is here: https://github.com/kierank/sxs-linux/blob/dma/sxs.c#L101 Apologies for the untidiness of the code, it’s entirely reverse engineered. Any help would be appreciated. Kieran
