kostirez1
Developer
The two possible approaches therefore are:
Block = 128 KiB, 256 sectors of 512 bytes, minimum size that can be physically erased
Speed to write 1x 256 KiB block (2x 128 KiB blocks) is ~2 seconds. Time to write a single 128 KiB block may or may not take ~1 second.
"DualBoot" approach - replace existing files in flash, no modifications to the file list:
[THEAD]
[/THEAD]
Pros: less blocks written (1 block saved), already tested approach
Cons: in case of a power failure => brick
Expected speed: 8 seconds, 8 of them critical
"Low risk" approach - put the two files at the end of the region, modify file list at the end:
[THEAD]
[/THEAD]
Pros: a power failure is tolerated if it happens during writes into the unreferenced area (a brick can still occur while updating the file list - although we need only ~1247 bytes of this block, the rest is ignored)
Cons: more blocks written (1 additional for the file list), currently not tested
Expected speed: 9 seconds, 1 of them critical
Offsets are from nofsm_patch_489.bin, they will be a little bit off in the physical flash (up to +0x30?), since noFSM patches don't contain CoreOS headers
Block = 128 KiB, 256 sectors of 512 bytes, minimum size that can be physically erased
Speed to write 1x 256 KiB block (2x 128 KiB blocks) is ~2 seconds. Time to write a single 128 KiB block may or may not take ~1 second.
"DualBoot" approach - replace existing files in flash, no modifications to the file list:
| Location | Offset start | Offset end | Block start | Block end | Block count |
| spu_pkg_rvk_verifier.self | 0x0404C8 | 0x04F7E7 | 0x040000 | 0x05FFFF | 1 |
| lv0 | 0x1EE200 | 0x2B642F | 0x1E0000 | 0x2BFFFF | 7 |
Cons: in case of a power failure => brick
Expected speed: 8 seconds, 8 of them critical
"Low risk" approach - put the two files at the end of the region, modify file list at the end:
| Location | Offset start | Offset end | Block start | Block end | Block count |
| File list | 0x000000 | 0x0004AF | 0x000000 | 0x01FFFF | 1 |
| spu_pkg_rvk_verifier.self | 0x5A0000 | 0x5AF31F | 0x5A0000 | 0x5BFFFF | 1 |
| lv0 | 0x5AF320 | 0x67754F | 0x5A0000 | 0x680000 | 7 new (+1 shared) |
Cons: more blocks written (1 additional for the file list), currently not tested
Expected speed: 9 seconds, 1 of them critical
Offsets are from nofsm_patch_489.bin, they will be a little bit off in the physical flash (up to +0x30?), since noFSM patches don't contain CoreOS headers


