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* x86: Move GDT to a safe location in RAMGraeme Russ2010-05-06-0/+96
| | | | | | | | | Currently, the GDT is either located in FLASH or in the non-relocated U-Boot image in RAM. Both of these locations are unsafe as those locations can be erased during a U-Boot update. Move the GDT into the highest available memory location and relocate U-Boot to just below it Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
* x86: Add RAM bootstrap functionalityGraeme Russ2010-05-06-0/+36
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* x86: Split sc520 memory sizing versus reportingGraeme Russ2010-05-06-0/+5
| | | | | | | | This patch allows the low-level assembler boot-strap to obtain the RAM size without calling the destructive 'sizer' routine. This allows boot-strapping from a U-Boot image loaded in RAM Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
* i386: Move cpu/i386/* to arch/i386/cpu/*Peter Tyser2010-04-13-0/+135
Signed-off-by: Peter Tyser <ptyser@xes-inc.com>