/* SPDX-License-Identifier: GPL-2.0-only */ #include <stdint.h> #if ENV_X86_64 /* * Assembly code that drops into protected mode and calls the function * specified as first argument, which must have been compiled for x86_32. * After the function returns it enters long mode again. * The function pointer destination must be below 4GiB in physical memory. * * The called function has 0-3 arguments and returns an int. */ int protected_mode_call_wrapper(uint32_t func_ptr, uint32_t opt_arg1, uint32_t opt_arg2, uint32_t opt_arg3); /* * Drops into protected mode and calls the function, which must have been compiled for x86_32. * After the function returns it enters long mode again. * The function pointer destination must be below 4GiB in physical memory. * * The called function doesn't have arguments and returns an int. */ static inline int protected_mode_call(void *func) { return protected_mode_call_wrapper((uintptr_t)func, 0, 0, 0); } /* * Drops into protected mode and calls the function, which must have been compiled for x86_32. * After the function returns it enters long mode again. * The function pointer destination must be below 4GiB in physical memory. * Only the lower 32bits of the argument are passed to the called function. * * The called function have one argument and returns an int. */ static inline int protected_mode_call_1arg(void *func, uint32_t arg1) { return protected_mode_call_wrapper((uintptr_t)func, arg1, 0, 0); } /* * Drops into protected mode and calls the function, which must have been compiled for x86_32. * After the function returns it enters long mode again. * The function pointer destination must be below 4GiB in physical memory. * Only the lower 32bits of the argument are passed to the called function. * * The called function has two arguments and returns an int. */ static inline int protected_mode_call_2arg(void *func, uint32_t arg1, uint32_t arg2) { return protected_mode_call_wrapper((uintptr_t)func, arg1, arg2, 0); } /* * Drops into protected mode and calls the function, which must have been compiled for x86_32. * After the function returns it enters long mode again. * The function pointer destination must be below 4GiB in physical memory. * Only the lower 32bits of the argument are passed to the called function. * * The called function has two arguments and returns an int. */ static inline int protected_mode_call_3arg(void *func, uint32_t arg1, uint32_t arg2, uint32_t arg3) { return protected_mode_call_wrapper((uintptr_t)func, arg1, arg2, arg3); } #else static inline int protected_mode_call(void *func) { int (*doit)(void) = func; return doit(); } static inline int protected_mode_call_1arg(void *func, uint32_t arg1) { int (*doit)(uint32_t arg1) = func; return doit(arg1); } static inline int protected_mode_call_2arg(void *func, uint32_t arg1, uint32_t arg2) { int (*doit)(uint32_t arg1, uint32_t arg2) = func; return doit(arg1, arg2); } static inline int protected_mode_call_3arg(void *func, uint32_t arg1, uint32_t arg2, uint32_t arg3) { int (*doit)(uint32_t arg1, uint32_t arg2, uint32_t arg3) = func; return doit(arg1, arg2, arg3); } #endif