From cdf92eacd5d2f85de473778cc1ebf35c2468a7f2 Mon Sep 17 00:00:00 2001 From: Julius Werner Date: Tue, 9 Dec 2014 12:18:00 -0800 Subject: 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 Reviewed-on: https://chromium-review.googlesource.com/234192 Reviewed-by: Aaron Durbin Signed-off-by: Patrick Georgi Reviewed-on: http://review.coreboot.org/9792 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel Reviewed-by: Stefan Reinauer --- src/Kconfig | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'src/Kconfig') diff --git a/src/Kconfig b/src/Kconfig index a6032c7d07..2663f5022d 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 -- cgit v1.2.3