Patrick Georgi (pgeorgi@google.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/9792
-gerrit
commit dcf541de52f119b9ec964d77787c0fb6e14bf641 Author: Julius Werner jwerner@chromium.org Date: Tue Dec 9 12:18:00 2014 -0800
rk3288: Disable ramstage compression by default
The ramstage is loaded from romstage, so the LZMA scratchpad buffer used to decompress it is part of the romstage BSS in SRAM. On RK3288, SRAM cannot be cached which makes the decompression so slow that it's faster to just load an uncompressed image from SPI. Disable ramstage compression on this SoC to account for that.
[pg: implementation avoids restructuring all of Kconfig]
BRANCH=None BUG=None TEST=Built for Pinky and Falco, confirmed that the former didn't have COMPRESS_RAMSTAGE in its .config and the latter still did. Measured a speed-up of about 35ms on Pinky. (For some weird reason, the decompression of the payload also takes way longer than on other platforms, although not as long as the ramstage. I have no explanation for that and can't really think of a good way to figure it out... maybe the Cortex-A12 is just terrible at some operation that LZMA uses a lot?)
Change-Id: I9f67f7537696ec09496483b16b59a8b73f4cb11b Signed-off-by: Julius Werner jwerner@chromium.org Reviewed-on: https://chromium-review.googlesource.com/234192 Reviewed-by: Aaron Durbin adurbin@chromium.org Signed-off-by: Patrick Georgi pgeorgi@chromium.org --- src/Kconfig | 7 ++++++- src/soc/rockchip/rk3288/Kconfig | 1 + 2 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/src/Kconfig b/src/Kconfig index a6032c7..2663f50 100644 --- a/src/Kconfig +++ b/src/Kconfig @@ -135,9 +135,14 @@ config STATIC_OPTION_TABLE every boot. Use this if you want the NVRAM configuration to never be modified from its default values.
+config UNCOMPRESSED_RAMSTAGE + bool + default n + config COMPRESS_RAMSTAGE bool "Compress ramstage with LZMA" - default y + default y if !UNCOMPRESSED_RAMSTAGE + default n help Compress ramstage to save memory in the flash image. Note that decompression might slow down booting if the boot flash diff --git a/src/soc/rockchip/rk3288/Kconfig b/src/soc/rockchip/rk3288/Kconfig index 48ea7fc..60d69f6 100644 --- a/src/soc/rockchip/rk3288/Kconfig +++ b/src/soc/rockchip/rk3288/Kconfig @@ -30,6 +30,7 @@ config SOC_ROCKCHIP_RK3288 select HAVE_UART_MEMORY_MAPPED select HAVE_UART_SPECIAL select BOOTBLOCK_CONSOLE + select UNCOMPRESSED_RAMSTAGE
if SOC_ROCKCHIP_RK3288