SPRZ422K August 2014 – May 2024 TMS320F28374S , TMS320F28375S , TMS320F28375S-Q1 , TMS320F28376S , TMS320F28377S , TMS320F28377S-Q1 , TMS320F28378S , TMS320F28379S
Memory: Prefetching Beyond Valid Memory
B, C
The C28x CPU prefetches instructions beyond those currently active in its pipeline. If the prefetch occurs past the end of valid memory, then the CPU may receive an invalid opcode.
M1, GS11, GS15 – The prefetch queue is 8 x16 words in depth. Therefore, code should not come within 8 words of the end of valid memory. Prefetching across the boundary between two valid memory blocks is all right.
Example 1: M1 ends at address 0x7FF and is not followed by another memory block. Code in M1 should be stored no farther than address 0x7F7. Addresses 0x7F8–0x7FF should not be used for code.
Example 2: M0 ends at address 0x3FF and valid memory (M1) follows it. Code in M0 can be stored up to and including address 0x3FF. Code can also cross into M1, up to and including address 0x7F7.
Flash – The prefetch queue is 16 x16 words in depth. Therefore, code should not come within 16 words of the end of valid memory; otherwise, it generates a Flash ECC uncorrectable error.
MEMORY TYPE | ADDRESSES IMPACTED | F28379S F28378S F28377S F28375S |
F28376S F28374S |
---|---|---|---|
M1 | 0x0000 07F8–0x0000 07FF | Yes | Yes |
GS11 | 0x0001 7FF8–0x0001 7FFF | No | Yes |
GS15 | 0x0001 BFF8–0x0001 BFFF | Yes | N/A |
Flash (Bank 0) | 0x000B FFF0–0x000B FFFF | No | Yes |
Flash (Bank 1) | 0x000F FFF0–0x000F FFFF | Yes | N/A |