Attention is currently required from: Rex-BC Chen, Paul Menzel. Hung-Te Lin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/61133 )
Change subject: soc/mediatek/mt8186: Support DRAM fast calibration using blob ......................................................................
Patch Set 19:
(2 comments)
Commit Message:
https://review.coreboot.org/c/coreboot/+/61133/comment/8050637c_6587383e PS19, Line 9: For the current SoCs the source code for DRAM fast calibration was added : to the source code repository. For MT8186 the DRAM fast calibration : source code won’t be published and put under a FLOSS license. The blob : has to be used to do this. What about this:
For most MediaTek SoCs (MT8183, MT8192, MT8195) we rely on an external program (e.g., the "DRAM blob") to do the full DRAM calibration first, then store and and apply the generated parameters to the reference "fast DRAM calibration" in the vendor/mediatek folder for normal system boot.
Starting with MT8186, the "DRAM blob" will also support fast calibration so both first boot and normal boot can follow the same path for DRAM calibration.
File src/soc/mediatek/common/memory.c:
https://review.coreboot.org/c/coreboot/+/61133/comment/4e316bfb_99500d06 PS19, Line 146: /* Set FAST_K flag */ I think the code below is simple enough to explain itself; instead the comment should describe how/why we are seeing the config here. For example
/* The loaded config should not contain FAST_K (done in full calibration), * so we have to set that now to indicate the blob taking the config instead * of generating a new config. */
Also, maybe we should move this to inside the if(CONFIG(MEDIATEK_BLOB_FAST_INIT)) { ... }