/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _SELFTESTS_POWERPC_BASIC_ASM_H #define _SELFTESTS_POWERPC_BASIC_ASM_H #include <ppc-asm.h> #include <asm/unistd.h> #define LOAD_REG_IMMEDIATE(reg, expr) \ lis reg, (expr)@highest; \ ori reg, reg, (expr)@higher; \ rldicr reg, reg, 32, 31; \ oris reg, reg, (expr)@high; \ ori reg, reg, (expr)@l; /* * Note: These macros assume that variables being stored on the stack are * doublewords, while this is usually the case it may not always be the * case for each use case. */ #if defined(_CALL_ELF) && _CALL_ELF == 2 #define STACK_FRAME_MIN_SIZE 32 #define STACK_FRAME_TOC_POS 24 #define __STACK_FRAME_PARAM(_param) (32 + ((_param)*8)) #define __STACK_FRAME_LOCAL(_num_params, _var_num) \ ((STACK_FRAME_PARAM(_num_params)) + ((_var_num)*8)) #else #define STACK_FRAME_MIN_SIZE 112 #define STACK_FRAME_TOC_POS 40 #define __STACK_FRAME_PARAM(i) (48 + ((i)*8)) /* * Caveat: if a function passed more than 8 doublewords, the caller will have * made more space... which would render the 112 incorrect. */ #define __STACK_FRAME_LOCAL(_num_params, _var_num) \ (112 + ((_var_num)*8)) #endif /* Parameter x saved to the stack */ #define STACK_FRAME_PARAM(var) __STACK_FRAME_PARAM(var) /* Local variable x saved to the stack after x parameters */ #define STACK_FRAME_LOCAL(num_params, var) \ __STACK_FRAME_LOCAL(num_params, var) #define STACK_FRAME_LR_POS 16 #define STACK_FRAME_CR_POS 8 /* * It is very important to note here that _extra is the extra amount of * stack space needed. This space can be accessed using STACK_FRAME_PARAM() * or STACK_FRAME_LOCAL() macros. * * r1 and r2 are not defined in ppc-asm.h (instead they are defined as sp * and toc). Kernel programmers tend to prefer rX even for r1 and r2, hence * %1 and %r2. r0 is defined in ppc-asm.h and therefore %r0 gets * preprocessed incorrectly, hence r0. */ #define PUSH_BASIC_STACK(_extra) \ mflr r0; \ std r0, STACK_FRAME_LR_POS(%r1); \ stdu %r1, -(_extra + STACK_FRAME_MIN_SIZE)(%r1); \ mfcr r0; \ stw r0, STACK_FRAME_CR_POS(%r1); \ std %r2, STACK_FRAME_TOC_POS(%r1); #define POP_BASIC_STACK(_extra) \ ld %r2, STACK_FRAME_TOC_POS(%r1); \ lwz r0, STACK_FRAME_CR_POS(%r1); \ mtcr r0; \ addi %r1, %r1, (_extra + STACK_FRAME_MIN_SIZE); \ ld r0, STACK_FRAME_LR_POS(%r1); \ mtlr r0; #endif /* _SELFTESTS_POWERPC_BASIC_ASM_H */