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authorGraeme Russ <graeme.russ@gmail.com>2010-04-24 00:05:42 +1000
committerWolfgang Denk <wd@denx.de>2010-05-06 00:15:31 +0200
commit077e1958ca4afe12d88043b123ded058c51b89f7 (patch)
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x86: Add RAM bootstrap functionality
Add a parameter to the 32-bit entry to indicate if entry is from Real Mode or not. If entry is from Real Mode, execute the destructive 'sizer' routine to determine memory size as we are booting cold and running in Flash. If not entering from Real Mode, we are executing a U-Boot image from RAM and therefore the memory size is already known (and running 'sizer' will destroy the running image) There are now two 32-bit entry points. The first is the 'in RAM' entry point which exists at the start of the U-Boot binary image. As such, you can load u-boot.bin in RAM and jump directly to the load address without needing to calculate any offsets. The second entry point is used by the real-to-protected mode switch This patch also changes TEXT_BASE to 0x6000000 (in RAM). You can load the resulting image at 0x6000000 and simple go 0x6000000 from the u-boot prompt Hopefully a later patch will completely elliminate any dependency on TEXT_BASE like a relocatable linux kernel (perfect world) Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
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