tools/testing/selftests/powerpc/include/basic_asm.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _SELFTESTS_POWERPC_BASIC_ASM_H
   3 #define _SELFTESTS_POWERPC_BASIC_ASM_H
   4
   5 #include <ppc-asm.h>
   6 #include <asm/unistd.h>
   7
   8 #ifdef __powerpc64__
   9 #define PPC_LL          ld
  10 #define PPC_STL         std
  11 #define PPC_STLU        stdu
  12 #else
  13 #define PPC_LL          lwz
  14 #define PPC_STL         stw
  15 #define PPC_STLU        stwu
  16 #endif
  17
  18 #define LOAD_REG_IMMEDIATE(reg, expr) \
  19         lis     reg, (expr)@highest;    \
  20         ori     reg, reg, (expr)@higher;        \
  21         rldicr  reg, reg, 32, 31;       \
  22         oris    reg, reg, (expr)@high;  \
  23         ori     reg, reg, (expr)@l;
  24
  25 /*
  26  * Note: These macros assume that variables being stored on the stack are
  27  * sizeof(long), while this is usually the case it may not always be the
  28  * case for each use case.
  29  */
  30 #ifdef  __powerpc64__
  31
  32 // ABIv2
  33 #if defined(_CALL_ELF) && _CALL_ELF == 2
  34 #define STACK_FRAME_MIN_SIZE 32
  35 #define STACK_FRAME_TOC_POS  24
  36 #define __STACK_FRAME_PARAM(_param)  (32 + ((_param)*8))
  37 #define __STACK_FRAME_LOCAL(_num_params, _var_num)  \
  38         ((STACK_FRAME_PARAM(_num_params)) + ((_var_num)*8))
  39
  40 #else // ABIv1 below
  41 #define STACK_FRAME_MIN_SIZE 112
  42 #define STACK_FRAME_TOC_POS  40
  43 #define __STACK_FRAME_PARAM(i)  (48 + ((i)*8))
  44
  45 /*
  46  * Caveat: if a function passed more than 8 doublewords, the caller will have
  47  * made more space... which would render the 112 incorrect.
  48  */
  49 #define __STACK_FRAME_LOCAL(_num_params, _var_num)  \
  50         (112 + ((_var_num)*8))
  51
  52
  53 #endif // ABIv2
  54
  55 // Common 64-bit
  56 #define STACK_FRAME_LR_POS   16
  57 #define STACK_FRAME_CR_POS   8
  58
  59 #else // 32-bit below
  60
  61 #define STACK_FRAME_MIN_SIZE 16
  62 #define STACK_FRAME_LR_POS   4
  63
  64 #define __STACK_FRAME_PARAM(_param)  (STACK_FRAME_MIN_SIZE + ((_param)*4))
  65 #define __STACK_FRAME_LOCAL(_num_params, _var_num)  \
  66         ((STACK_FRAME_PARAM(_num_params)) + ((_var_num)*4))
  67
  68 #endif // __powerpc64__
  69
  70 /* Parameter x saved to the stack */
  71 #define STACK_FRAME_PARAM(var)    __STACK_FRAME_PARAM(var)
  72
  73 /* Local variable x saved to the stack after x parameters */
  74 #define STACK_FRAME_LOCAL(num_params, var)    \
  75         __STACK_FRAME_LOCAL(num_params, var)
  76
  77 /*
  78  * It is very important to note here that _extra is the extra amount of
  79  * stack space needed. This space can be accessed using STACK_FRAME_PARAM()
  80  * or STACK_FRAME_LOCAL() macros.
  81  *
  82  * r1 and r2 are not defined in ppc-asm.h (instead they are defined as sp
  83  * and toc). Kernel programmers tend to prefer rX even for r1 and r2, hence
  84  * %1 and %r2. r0 is defined in ppc-asm.h and therefore %r0 gets
  85  * preprocessed incorrectly, hence r0.
  86  */
  87 #define PUSH_BASIC_STACK(_extra) \
  88         mflr     r0; \
  89         PPC_STL  r0, STACK_FRAME_LR_POS(%r1); \
  90         PPC_STLU %r1, -(((_extra + 15) & ~15) + STACK_FRAME_MIN_SIZE)(%r1);
  91
  92 #define POP_BASIC_STACK(_extra) \
  93         addi    %r1, %r1, (((_extra + 15) & ~15) + STACK_FRAME_MIN_SIZE); \
  94         PPC_LL  r0, STACK_FRAME_LR_POS(%r1); \
  95         mtlr    r0;
  96
  97 .macro OP_REGS op, reg_width, start_reg, end_reg, base_reg, base_reg_offset=0, skip=0
  98         .set i, \start_reg
  99         .rept (\end_reg - \start_reg + 1)
 100         \op     i, (\reg_width * (i - \skip) + \base_reg_offset)(\base_reg)
 101         .set i, i + 1
 102         .endr
 103 .endm
 104
 105 #endif /* _SELFTESTS_POWERPC_BASIC_ASM_H */