arch/x86/boot: Jump to payload in protected mode

*   On ARCH_RAMSTAGE_X86_64 jump to the payload in protected mode.
*   Add a helper function to jump to arbitrary code in protected mode,
    similar to the real mode call handler.
*   Doesn't affect existing x86_32 code.
*   Add a macro to cast pointer to uint32_t that dies if it would overflow
    on conversion

Tested on QEMU Q35 using SeaBIOS as payload.
Tested on Lenovo T410 with additional x86_64 patches.

Change-Id: I6552ac30f1b6205e08e16d251328e01ce3fbfd14
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/30118
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>

0 files changed, 0 insertions, 0 deletions