Change in coreboot[master]: sod/amd/cezanne: Use LZ4 for FSP-M when using SPI DMA

[Raul Rangel (Code Review)]

Attention is currently required from: Jason Glenesk, Marshall Dawson, Felix Held.
Raul Rangel has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/59029 )

Change subject: sod/amd/cezanne: Use LZ4 for FSP-M when using SPI DMA
......................................................................

sod/amd/cezanne: Use LZ4 for FSP-M when using SPI DMA

This change adds about 30 KiB to FSP-M. When not using the SPI DMA
controller, this change actually has a ~7 second boot time penalty. When
we use the DMA engine, we end up with about a 5 second decrease. Once we
switch to 100 MHz SPI this will help even more since we have effectively
eliminated the decompression time.

BUG=b:179699789
TEST=Boot nipperkin to OS and take boot time measurements
fspm.bin                       0x2efc0    fsp             90953 LZMA (233472 decompressed)
fspm.bin                       0x2cfc0    fsp            121156 LZ4  (233472 decompressed)

- FSP-M / no async -
| 508 - finished loading body                         | 177.019   | 179.384   Δ(  2.36,    0.16%) |
...
| 970 - loading FSP-M                                 | 0.346     | 0.346     Δ(  0.00,    0.00%) |
| 17 - starting LZ4 decompress (ignore for x86)       | 0.009     | 0.01      Δ(  0.00,    0.00%) |
| 18 - finished LZ4 decompress (ignore for x86)       | 53.916    | 59.475    Δ(  5.56,    0.37%) |

- FSP-M / async -
| 508 - finished loading body                         | 177.185   | 179.689   Δ(  2.50,    0.18%) |
...
| 970 - loading FSP-M                                 | 0.989     | 0.99      Δ(  0.00,    0.00%) |
| 17 - starting LZ4 decompress (ignore for x86)       | 9.483     | 12.877    Δ(  3.39,    0.24%) |
| 18 - finished LZ4 decompress (ignore for x86)       | 10.833    | 0.312     Δ(-10.52,   -0.75%) |

Signed-off-by: Raul E Rangel 
Change-Id: I7d0363d27d98d4ed3afc6f802a13ff7986391921
---
M src/soc/amd/cezanne/Kconfig
1 file changed, 2 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/29/59029/1

diff --git a/src/soc/amd/cezanne/Kconfig b/src/soc/amd/cezanne/Kconfig
index fc0173a..92f7e9d 100644
--- a/src/soc/amd/cezanne/Kconfig
+++ b/src/soc/amd/cezanne/Kconfig
@@ -20,7 +20,8 @@
    select DRIVERS_USB_ACPI
    select DRIVERS_I2C_DESIGNWARE
    select DRIVERS_USB_PCI_XHCI
-	select FSP_COMPRESS_FSP_M_LZMA
+	select FSP_COMPRESS_FSP_M_LZMA if !ASYNC_FILE_LOADING
+	select FSP_COMPRESS_FSP_M_LZ4 if ASYNC_FILE_LOADING
    select FSP_COMPRESS_FSP_S_LZ4
    select GENERIC_GPIO_LIB
    select HAVE_ACPI_TABLES