Intel(R) IQ80315 I/O Processor DMA and XOR Library APIs and ...

Intel ® GW80314 I/O Processor DMA and XOR LibraryLibrary6.1.1 Flow Sequence Description: XOR and DMA Library6.1.1.1 Initializationlib_mem_map_malloc()lib_set_xcb_mem_range()lib_new_mgr()lib_init()callintHandlerAttach()mpic_setup()Allocates separate memory regions for XOR descriptors, DMAdescriptors and Data. Records memory map to data structureMemmap_Typemem_map;Sets xcb bits for address range. This is used in conjunction with globalvariable mem_map to set descriptor and data address ranges.Allocates memory for XorDma_80314_Type data structure.Initialize XorDma_80314_Type data structure. The Free Stacksand Post Queues are initialized.Chains interrupt handlers lib_irq_handler() and lib_fiq_handler() intointerrupt vectors.Called to unmask/mask and route interrupts for DMA and XOR.6.1.1.2 Requestlib_stack_pop() is called to get a aligned buffer from the Free Stack. The alignment allows thesame buffer to be used as a DMA or XOR descriptor.In the case of an append, the descriptor values are written. Then, when the cache policy for thememory region used by the descriptors is either 010, 011 or 111 (caches on), the descriptor needsto be flushed to RAM using a macro. Function lib_postq_append_resume_sram() orlib_postq_append_resume_sdram() are called to append the descriptor to the channel descriptord chain, place in post queue, records to global variable chainTailXORDMA[], then sets resume tostart the transaction.6.1.1.3 Post Transaction CleanupAt some point descriptors for completed transactions must be reclaimed from the Post Queues andreturned to the Free Stack (when append is used). This is accomplished by calling lib_reclaim().APIs and Testbench White Paper 23