On 06/04 18:28, Bin Meng wrote: > Currently the FSP execution environment GDT is setup by U-Boot in > arch/x86/cpu/start16.S, which works pretty well. But if we try to > move the FspInitEntry call a little bit later to better fit into > U-Boot's initialization sequence, FSP will fail to bring up the AP > due to #GP fault as AP's GDT is duplicated from BSP whose GDT is > now moved into CAR, and unfortunately FSP calls AP initialization > after it disables the CAR. So basically the BSP's GDT still refers > to the one in the CAR, whose content is no longer available, so > when AP starts up and loads its segment register, it blows up. > > To resolve this, we load GDT before calling into FspInitEntry. > The GDT is the same one used in arch/x86/cpu/start16.S, which is > in the ROM and exists forever. > > Signed-off-by: Bin Meng <[email protected]> > > --- > > Changes in v2: > - Use CONFIG_RESET_SEG_START to avoid duplication > > arch/x86/cpu/cpu.c | 20 ++++++++++++++++++++ > arch/x86/cpu/start16.S | 1 + > arch/x86/include/asm/u-boot-x86.h | 3 +++ > arch/x86/lib/fsp/fsp_support.c | 3 +++ > 4 files changed, 27 insertions(+)
Tested-by: Andrew Bradford <[email protected]> _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
