rockchip: rk3399-gru: Fix max SPL size on bob and kevin
Chromebook bob and kevin typically run coreboot as the initial boot
loader, however, U-Boot proper can be used as a secondary boot loader.
It is also possible to run U-Boot SPL and proper bare metal, with SPL
and the U-Boot payload loaded from SPI flash.
Because of this chromebook bob and kevin only use SPL and not TPL+SPL
like other RK3399 boards, this mean that SPL is loaded to and run from
SRAM instead of DRAM.
The U-Boot payload is located at 0x40000 (256 KiB) offset in SPI flash
and because the BROM only read first 2 KiB for each 4 KiB page, the size
of SPL (idbloader.img) is limited to max 128 KiB.
The chosen bss start address further limits the size of SPL to 120 KiB.
0xff8e0000 (SPL_BSS_START_ADDR) - 0xff8c2000 (SPL_TEXT_BASE) = 0x1e000
Update SPL_MAX_SIZE to reflect the 120 KiB max size limitation.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/configs/chromebook_bob_defconfig b/configs/chromebook_bob_defconfig
index 55d4470..805da11 100644
--- a/configs/chromebook_bob_defconfig
+++ b/configs/chromebook_bob_defconfig
@@ -35,7 +35,7 @@
CONFIG_BLOBLIST=y
CONFIG_BLOBLIST_ADDR=0x100000
CONFIG_BLOBLIST_SIZE=0x1000
-CONFIG_SPL_MAX_SIZE=0x2e000
+CONFIG_SPL_MAX_SIZE=0x1e000
CONFIG_SPL_PAD_TO=0x7f8000
CONFIG_HANDOFF=y
# CONFIG_SPL_RAW_IMAGE_SUPPORT is not set