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/* 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 */
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