[coreboot-gerrit] [M] Change in coreboot[master]: soc/amd/common/block/lpc/spi_dma: Leverage CBFS_CACHE when using SPI DMA

[Raul Rangel (Code Review)]

Attention is currently required from: Jason Glenesk, Matt DeVillier, Martin Roth, Fred Reitberger, Tim Van Patten, Karthik Ramasubramanian, Felix Held.

Raul Rangel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74334 )

Change subject: soc/amd/common/block/lpc/spi_dma: Leverage CBFS_CACHE when using SPI DMA
......................................................................

Patch Set 4: Code-Review+2

(3 comments)

File src/soc/amd/common/block/lpc/spi_dma.c:

https://review.coreboot.org/c/coreboot/+/74334/comment/00b55a29_66054c1d 
PS4, Line 54: can_use_dma
Have you checked if all the new targets we are reading are 64byte aligned?

https://review.coreboot.org/c/coreboot/+/74334/comment/d9744c76_1c70300d 
PS4, Line 228: spi_dma_readat
When I took a stab at this, I tried keeping the mmap semantics because the ucode update code would mmap the whole ucode blob, and iterate reading only 4 bytes for each type of ucode. We didn't want to read the whole thing into RAM since that would be a waste. It looks like the ucode update code has been refactored to have individual files, so we no longer need to iterate the ucode blobs.
https://source.corp.google.com/chromeos_public/src/third_party/coreboot/src/...

I'm glad we are getting the SPI dma benefits without the complexity of preload!

File src/soc/amd/mendocino/Kconfig:

https://review.coreboot.org/c/coreboot/+/74334/comment/e974ff01_e37aa91f 
PS4, Line 246: SOC_AMD_COMMON_BLOCK_LPC_SPI_DMA
We should back port this to guybrush and skyrim :)