From: Peng Fan peng.fan@nxp.com
Implement armv8_el2_to_aarch32 for aarch64 U-Boot booting aarch32 SMP linux. It will trap to ATF to let ATF handle the mode switching.
Signed-off-by: Peng Fan peng.fan@nxp.com --- arch/arm/mach-imx/lowlevel.S | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+)
diff --git a/arch/arm/mach-imx/lowlevel.S b/arch/arm/mach-imx/lowlevel.S index 158fdb7d87..c500aa8123 100644 --- a/arch/arm/mach-imx/lowlevel.S +++ b/arch/arm/mach-imx/lowlevel.S @@ -20,3 +20,26 @@ ENTRY(lowlevel_init) isb ret ENDPROC(lowlevel_init) + +/* + * Switch from AArch64 EL2 to AArch32 EL2 + * @param inputs: + * x0: argument, zero + * x1: machine nr + * x2: fdt address + * x3: input argument + * x4: kernel entry point + * @param outputs for secure firmware: + * x0: function id + * x1: kernel entry point + * x2: machine nr + * x3: fdt address +*/ +.global armv8_el2_to_aarch32 +armv8_el2_to_aarch32: + mov x3, x2 + mov x2, x1 + mov x1, x4 + ldr x0, =0xc20000fd + smc #0 + ret