1#ifndef _SELFTESTS_POWERPC_BASIC_ASM_H
 2#define _SELFTESTS_POWERPC_BASIC_ASM_H
 3
 4#include <ppc-asm.h>
 5#include <asm/unistd.h>
 6
 7#define LOAD_REG_IMMEDIATE(reg,expr) \
 8	lis	reg,(expr)@highest;	\
 9	ori	reg,reg,(expr)@higher;	\
10	rldicr	reg,reg,32,31;	\
11	oris	reg,reg,(expr)@high;	\
12	ori	reg,reg,(expr)@l;
13
14/*
15 * Note: These macros assume that variables being stored on the stack are
16 * doublewords, while this is usually the case it may not always be the
17 * case for each use case.
18 */
19#if defined(_CALL_ELF) && _CALL_ELF == 2
20#define STACK_FRAME_MIN_SIZE 32
21#define STACK_FRAME_TOC_POS  24
22#define __STACK_FRAME_PARAM(_param)  (32 + ((_param)*8))
23#define __STACK_FRAME_LOCAL(_num_params,_var_num)  ((STACK_FRAME_PARAM(_num_params)) + ((_var_num)*8))
24#else
25#define STACK_FRAME_MIN_SIZE 112
26#define STACK_FRAME_TOC_POS  40
27#define __STACK_FRAME_PARAM(i)  (48 + ((i)*8))
28
29/*
30 * Caveat: if a function passed more than 8 doublewords, the caller will have
31 * made more space... which would render the 112 incorrect.
32 */
33#define __STACK_FRAME_LOCAL(_num_params,_var_num)  (112 + ((_var_num)*8))
34#endif
35
36/* Parameter x saved to the stack */
37#define STACK_FRAME_PARAM(var)    __STACK_FRAME_PARAM(var)
38
39/* Local variable x saved to the stack after x parameters */
40#define STACK_FRAME_LOCAL(num_params,var)    __STACK_FRAME_LOCAL(num_params,var)
41#define STACK_FRAME_LR_POS   16
42#define STACK_FRAME_CR_POS   8
43
44/*
45 * It is very important to note here that _extra is the extra amount of
46 * stack space needed. This space can be accessed using STACK_FRAME_PARAM()
47 * or STACK_FRAME_LOCAL() macros.
48 *
49 * r1 and r2 are not defined in ppc-asm.h (instead they are defined as sp
50 * and toc). Kernel programmers tend to prefer rX even for r1 and r2, hence
51 * %1 and %r2. r0 is defined in ppc-asm.h and therefore %r0 gets
52 * preprocessed incorrectly, hence r0.
53 */
54#define PUSH_BASIC_STACK(_extra) \
55	mflr	r0; \
56	std	r0,STACK_FRAME_LR_POS(%r1); \
57	stdu	%r1,-(_extra + STACK_FRAME_MIN_SIZE)(%r1); \
58	mfcr	r0; \
59	stw	r0,STACK_FRAME_CR_POS(%r1); \
60	std	%r2,STACK_FRAME_TOC_POS(%r1);
61
62#define POP_BASIC_STACK(_extra) \
63	ld	%r2,STACK_FRAME_TOC_POS(%r1); \
64	lwz	r0,STACK_FRAME_CR_POS(%r1); \
65	mtcr	r0; \
66	addi	%r1,%r1,(_extra + STACK_FRAME_MIN_SIZE); \
67	ld	r0,STACK_FRAME_LR_POS(%r1); \
68	mtlr	r0;
69
70#endif /* _SELFTESTS_POWERPC_BASIC_ASM_H */