Is there any example on how to use sdhc driver in ( https://github.com/SEL4PROJ/projects_libs/tree/master/libsdhcdrivers)? Currently, I'm struggling to read a block of data from micro-sd in seL4. I use the following code (assertions are omitted here for readability) to instantiate the driver : ps_io_mapper_t io_mapper = {0}; error = sel4platsupport_new_io_mapper(simple, vspace, vka, &io_mapper); ps_dma_man_t dma_man = {0}; error = sel4utils_new_page_dma_alloc(&vka, &vspace, &dma_man); ps_io_ops_t io_ops = { .io_mapper = io_mapper, .dma_manager = dma_man }; sdio_host_dev_t* dev = (sdio_host_dev_t*) malloc(sizeof(*dev)); assert(dev != NULL); memset(dev,0, sizeof(*dev)); enum sdio_id id = sdio_default_id(); error = sdio_init(id, &io_ops, dev); mmc_card_t* mmc_card = (mmc_card_t*) malloc(sizeof(*mmc_card)); error = mmc_init(dev, &io_ops, mmc_card); void* vaddr = (void*) 0x1980000; uintptr_t paddr = (uintptr_t) 0x119a7000; long read_len = mmc_block_read(*mmc_card, 0, 5, vaddr, paddr, NULL, NULL); And the code's stuck in mmc_block_read function where interrupt status (BRR and BWR) are never on. Thanks in advance, Oak -- Norrathep (Oak) Rattanavipanon M.S. in Computer Science University of California - Irvine