Intel 80310 I/O Processor Chipset AAU Coding Techniques

Intel ® 80310 I/O Processor Chipset AAU Coding TechniquesExample Calling Source CodeAppendix B Example Calling Source CodeB.1 Standard CallsSupport functions for the 80310 AAU===========================================Dave Jiang Last updated: 09/18/2001The Intel® 80312 I/O companion chip in the 80310 chipset contains an AAU. TheAAU is capable of processing up to 8 data block sources and perform XORoperations on them. This unit is typically used to accelerated XORoperations utilized by RAID storage device drivers such as RAID 5. ThisAPI is designed to provide a set of functions to take advantage of theAAU. The AAU can also be used to transfer data blocks and used as a memorycopier. The AAU transfer the memory faster than the operation performed byusing CPU copy therefore it is recommended to use the AAU for memory copy.------------------int aau_request(u32 *aau_context, const char *device_id);This function allows the user the acquire the control of the AAU. Thefunction will return a context of AAU to the user and allocatean interrupt for the AAU. The user must pass the context as a parameter tovarious AAU API calls.int aau_queue_buffer(u32 aau_context, aau_head_t *listhead);This function starts the AAU operation. The user must create a SGLheader with a SGL attached. The format is presented below. The SGL isbuilt from kernel memory./* hardware descriptor */typedef struct _aau_desc{White Paper 67