6.6.4 OCMC
There is one on-chip memory controller (OCMC) in the device.
The OCM Controller supports the following features:
- L3_MAIN data interface:
- Used for maximum throughput performance
- 128-bit data bus width
- Burst supported
- L4 interface (OCMC_RAM only):
- Used for access to configuration registers
- 32-bit data bus width
- Only single accesses supported
- The L4 associated OCMC clock is two times lower than the L3 associated OCMC clock
- Error correction and detection:
- Single error correction and dual error detection
- 9-bit Hamming error correction code (ECC) calculated on 128-bit data word which is concatenated with memory address bits
- Hamming distance of 4
- Enable/Disable mode control through a dedicated register
- Single bit error correction on a read transaction
- Exclusion of repeated addresses from correctable error address trace history
- ECC valid for all write transactions to an enabled region
- Sub-128-bit writes supported via read modify write
- ECC Error Status Reporting:
- Trace history buffer (FIFO) with depth of 4 for corrected error address
- Trace history buffer with depth of 4 for non correctable error address and also including double error detection
- Interrupt generation for correctable and uncorrectable detected errors
- ECC Diagnostics Configuration:
- Counters for single error correction (SEC), double error detection (DED) and address error events (AEE)
- Programmable threshold registers for exeptions associated with SEC, DED and AEE counters
- Register control for enabling and disabling of diagnostics
- Configuration registers and ECC status accessible through L4 interconnect
- Circular buffer for sliced based VIP frame transfers:
- Up to 12 programmable circular buffers mapped with unique virtual frame addresses
- On the fly (with no additional latency) address translation from virtual to OCMC circular buffer memory space
- Virtual frame size up to 8 MiB and circular buffer size up to 1 MiB
- Error handling and reporting of illegal CBUF addressing
- Underflow and Overflow status reporting and error handling
- Last access read/write address history
- Two Interrupt outputs configured independently to service either ECC or CBUF interrupt events
The OCM controller does not have a memory protection logic and does not support endianism conversion.
For more information, see section On-Chip Memory (OCM) in chapter Memory Subsystem of the Device TRM.