[XL] Change in coreboot[main]: soc/sifive/fu740: Add FU740 SOC

[ron minnich (Code Review)]

Attention is currently required from: Martin L Roth, Maximilian Brune, Philipp Hug.

ron minnich has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/76689?usp=email )

Change subject: soc/sifive/fu740: Add FU740 SOC
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Patch Set 13: Code-Review+2

(2 comments)

File src/soc/sifive/fu740/cbmem.c:

https://review.coreboot.org/c/coreboot/+/76689/comment/915e84ef_6fe1b34b :
PS12, Line 11: #define FU740_MAXDRAM 0x800000000ULL // 32 GiB
> I only put it in here to emphasis it is only used here and for all other operations `sdram_size()` i […]

Acknowledged

File src/soc/sifive/fu740/spi_internal.h:

https://review.coreboot.org/c/coreboot/+/76689/comment/ebbb8984_9a384b75 :
PS12, Line 1: /* SPDX-License-Identifier: GPL-2.0-only */
> This file contains the SPI stuff that is not needed outside of the SOC code. `include/soc/spi. […]

Acknowledged