u-boot.git/arch/x86/cpu/start.S, branch v2016.09

x86: Support a chained-boot development flow

2016-03-17T02:27:27Z

Sometimes it is useful to jump into U-Boot directly from coreboot or UEFI without any 16-bit init. This can help during development by allowing U-Boot to avoid doing all the init required by the platform. U-Boot expects its GDT to be set up correctly by its 16-bit code. If coreboot doesn't do this (because it hasn't run the payload setup code yet) then this won't happen. In this case we cannot rely on the GDT settings. U-Boot will hang or crash if these are wrong. Provide a development-only option to set up the GDT correctly. This is just a hack so you can jump to U-Boot from any stage of coreboot, not just at the end. Signed-off-by: Simon Glass Reviewed-by: Bin Meng

Fix board init code to respect the C runtime environment

2016-01-14T02:05:17Z

board_init_f_mem() alters the C runtime environment's stack it is actually already using. This is not a valid behaviour within a C runtime environment. Split board_init_f_mem into C functions which do not alter their own stack and always behave properly with respect to their C runtime environment. Signed-off-by: Albert ARIBAUD Acked-by: Thomas Chou

x86: Init the debug UART if enabled

2015-10-21T13:46:50Z

If the debug UART is enabled, get it ready for use at the earliest possible opportunity. This is not actually very early, but until we have a stack it is difficult to make it work. Signed-off-by: Simon Glass Reviewed-by: Bin Meng

x86: fsp: Add comments about U-Boot entering start.S twice

2015-08-26T14:54:11Z

Add some comments in start.S for the fact that with FSP U-Boot actually enters the code twice. Also change to use fsp_init() and fsp_continue for accuracy. Signed-off-by: Bin Meng Acked-by: Simon Glass

x86: fsp: Enlarge the size of malloc() pool before relocation

2015-08-26T14:54:11Z

After fsp_init() returns, the stack has already been switched to a place within system memory as defined by CONFIG_FSP_TEMP_RAM_ADDR. Enlarge the size of malloc() pool before relocation since we have plenty of memory now. Signed-off-by: Bin Meng Acked-by: Simon Glass

x86: Switch to using generic global_data setup

2015-08-14T15:50:10Z

There is quite a bit of assembler code that can be removed if we use the generic global_data setup. Less arch-specific code makes it easier to add new features and maintain the start-up code. Drop the unneeded code and adjust the hooks in board_f.c to cope. Signed-off-by: Simon Glass Reviewed-by: Bin Meng

x86: Enable debug UART for Minnowmax

2015-08-06T13:44:30Z

Enable the debug UART and emit a single 'a' early in the init sequence to show that it is working. Unfortunately the debug UART implementation needs a stack to work. I cannot seem to remove this limitation as the absolute 'jmp %eax' instruction goes off into the weeds. So this means that the character output cannot be any earlier than car_init_ret, where memory is available for a stack. Signed-off-by: Simon Glass Reviewed-by: Lukasz Majewski

x86: Add support for passing tables into U-Boot

2015-08-05T14:44:07Z

The EFI stub provides information to U-Boot in a table. This includes the memory map which is needed to decide where to relocate U-Boot. Collect this information in the early init code and store it in global_data. Fix up the BIST code at the same time since we don't have it when booting from EFI and can assume it is 0. Signed-off-by: Simon Glass Reviewed-by: Bin Meng

x86: Tidy up global_data flags

2015-08-05T14:42:40Z

These flags now overlap some global ones. Adjust the x86-specific flags to avoid this. Since this requires a change to the start.S code, add a way for tools to find the 32-bit cold reset entry point. Previously this was at a fixed offset. Signed-off-by: Simon Glass Reviewed-by: Bin Meng

x86: Add various minor tidy-ups to the 32-bit startup code

2015-08-05T14:42:40Z

Fix a typo, improve some comments and add a little more detail in some cases. Signed-off-by: Simon Glass Reviewed-by: Bin Meng