[L] Change in coreboot[main]: soc/mediatek/mt8196: Add GPUEB support

[Yidi Lin (Code Review)]

Attention is currently required from: Hung-Te Lin, Jarried Lin, Yu-Ping Wu.

Yidi Lin has posted comments on this change by Jarried Lin. ( https://review.coreboot.org/c/coreboot/+/85654?usp=email )

Change subject: soc/mediatek/mt8196: Add GPUEB support
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Patch Set 2:

(1 comment)

File src/soc/mediatek/mt8196/gpueb.c:

https://review.coreboot.org/c/coreboot/+/85654/comment/266bd7e1_f8856bae?usp... :
PS2, Line 305: 	write32p(GPUEB_INFO, (uintptr_t)mcu->load_buffer);
             : 	write32p(GPUEB_ABNORMAL_BOOT, 0);
             : 	write32p(GPUEB_WARM_BOOT, 0);
             : 	write32p(GPUMPU_RSV_ADDR, (uintptr_t)_resv_mem_gpueb >> PAGE_SHIFT);
Can you explain this part ? I don't quite understand why it writes `mcu->load_buffer` to `GPUEB_INFO`. `mcu->load_buffer` is pointing to a shared DMA buffer. Will GPUEB HW copy the content of `mcu->load_buffer` to somewhere ?