Intel CONTROLLERS 413808 - Manual (Page 528)

Intel
®
413808 and 413812—SRAM Memory Controller
Intel ® 413808 and 413812 I/O Controllers in TPER Mode
Developer’s Manual October 2007
528 Order Number: 317805-001US
8.3.4 Byte Parity Checking and Generation
All the direct memory ports of the SMCU supports byte-wise parity on the data bus.
For write requests made to an SMCU port, the direct memory port interface performs
the following tasks when receiving data:
• checks for data parity on the incoming data (parity error is logged if detected)
• generates ECC on the data
For the memory ports that are connected to the south internal bus, the write data
parity is received from the south internal bus as driven by the initiator of the data on
the south internal bus. For example, south internal bus initiators generate data parity.
Since the north internal bus does not support parity, data parity is generated by the
north internal bus port as the data enters the port and before it is written to the data
queue.
For read requests made to an SMCU port, the direct memory port interface performs
the following tasks before delivering data:
• checks for ECC on the data read from memory
• generates data parity on the data before delivering it on the port
For the memory ports that are connected to the south internal bus, the read data parity
that are generated by the SMCU are directly driven onto the south internal bus to the
requester. The data parity is then verified by the requester. Since the north internal bus
does not support parity, the read data parity that are generated by the SMCU are
verified by the north internal bus port when the data is read out of the data queue and
before being delivered onto the north internal bus. If the north internal bus port detects
a parity error while reading the data out of the data queue, the north internal bus port
will return a target abort.
Figure 61. Logical Data Access Paths with Parity Protection
Direct Memory
Data_in
Data_in Parity
Data_out Parity
Data_out
Port Interface
SRAM Controller
B6360-01