tools/testing/selftests/powerpc/math/fpu_asm.S

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * Copyright 2015, Cyril Bur, IBM Corp.
   4  */
   5
   6 #include "basic_asm.h"
   7 #include "fpu_asm.h"
   8
   9 FUNC_START(check_fpu)
  10         mr r4,r3
  11         li      r3,1 # assume a bad result
  12         lfd     f0,0(r4)
  13         fcmpu   cr1,f0,f14
  14         bne     cr1,1f
  15         lfd     f0,8(r4)
  16         fcmpu   cr1,f0,f15
  17         bne     cr1,1f
  18         lfd     f0,16(r4)
  19         fcmpu   cr1,f0,f16
  20         bne     cr1,1f
  21         lfd     f0,24(r4)
  22         fcmpu   cr1,f0,f17
  23         bne     cr1,1f
  24         lfd     f0,32(r4)
  25         fcmpu   cr1,f0,f18
  26         bne     cr1,1f
  27         lfd     f0,40(r4)
  28         fcmpu   cr1,f0,f19
  29         bne     cr1,1f
  30         lfd     f0,48(r4)
  31         fcmpu   cr1,f0,f20
  32         bne     cr1,1f
  33         lfd     f0,56(r4)
  34         fcmpu   cr1,f0,f21
  35         bne     cr1,1f
  36         lfd     f0,64(r4)
  37         fcmpu   cr1,f0,f22
  38         bne     cr1,1f
  39         lfd     f0,72(r4)
  40         fcmpu   cr1,f0,f23
  41         bne     cr1,1f
  42         lfd     f0,80(r4)
  43         fcmpu   cr1,f0,f24
  44         bne     cr1,1f
  45         lfd     f0,88(r4)
  46         fcmpu   cr1,f0,f25
  47         bne     cr1,1f
  48         lfd     f0,96(r4)
  49         fcmpu   cr1,f0,f26
  50         bne     cr1,1f
  51         lfd     f0,104(r4)
  52         fcmpu   cr1,f0,f27
  53         bne     cr1,1f
  54         lfd     f0,112(r4)
  55         fcmpu   cr1,f0,f28
  56         bne     cr1,1f
  57         lfd     f0,120(r4)
  58         fcmpu   cr1,f0,f29
  59         bne     cr1,1f
  60         lfd     f0,128(r4)
  61         fcmpu   cr1,f0,f30
  62         bne     cr1,1f
  63         lfd     f0,136(r4)
  64         fcmpu   cr1,f0,f31
  65         bne     cr1,1f
  66         li      r3,0 # Success!!!
  67 1:      blr
  68
  69
  70 // int check_all_fprs(double darray[32])
  71 FUNC_START(check_all_fprs)
  72         PUSH_BASIC_STACK(8)
  73         mr      r4, r3  // r4 = darray
  74         li      r3, 1   // prepare for failure
  75
  76         stfd    f31, STACK_FRAME_LOCAL(0, 0)(sp) // backup f31
  77
  78         // Check regs f0-f30, using f31 as scratch
  79         .set i, 0
  80         .rept 31
  81         lfd     f31, (8 * i)(r4)        // load expected value
  82         fcmpu   cr0, i, f31             // compare
  83         bne     cr0, 1f                 // bail if mismatch
  84         .set i, i + 1
  85         .endr
  86
  87         lfd     f31, STACK_FRAME_LOCAL(0, 0)(sp) // reload f31
  88         stfd    f30, STACK_FRAME_LOCAL(0, 0)(sp) // backup f30
  89
  90         lfd     f30, (8 * 31)(r4)       // load expected value of f31
  91         fcmpu   cr0, f30, f31           // compare
  92         bne     cr0, 1f                 // bail if mismatch
  93
  94         lfd     f30, STACK_FRAME_LOCAL(0, 0)(sp) // reload f30
  95
  96         // Success
  97         li      r3, 0
  98
  99 1:      POP_BASIC_STACK(8)
 100         blr
 101 FUNC_END(check_all_fprs)
 102
 103 FUNC_START(test_fpu)
 104         # r3 holds pointer to where to put the result of fork
 105         # r4 holds pointer to the pid
 106         # f14-f31 are non volatiles
 107         PUSH_BASIC_STACK(256)
 108         PUSH_FPU(256)
 109         std     r3,STACK_FRAME_PARAM(0)(sp) # Address of darray
 110         std r4,STACK_FRAME_PARAM(1)(sp) # Address of pid
 111
 112         // Load FPRs with expected values
 113         OP_REGS lfd, 8, 0, 31, r3
 114
 115         li      r0,__NR_fork
 116         sc
 117
 118         # pass the result of the fork to the caller
 119         ld      r9,STACK_FRAME_PARAM(1)(sp)
 120         std     r3,0(r9)
 121
 122         ld r3,STACK_FRAME_PARAM(0)(sp)
 123         bl check_all_fprs
 124         nop
 125
 126         POP_FPU(256)
 127         POP_BASIC_STACK(256)
 128         blr
 129 FUNC_END(test_fpu)
 130
 131 # int preempt_fpu(double *darray, int *threads_running, int *running)
 132 # On starting will (atomically) decrement not_ready as a signal that the FPU
 133 # has been loaded with darray. Will proceed to check the validity of the FPU
 134 # registers while running is not zero.
 135 FUNC_START(preempt_fpu)
 136         PUSH_BASIC_STACK(256)
 137         PUSH_FPU(256)
 138         std r3,STACK_FRAME_PARAM(0)(sp) # double *darray
 139         std r4,STACK_FRAME_PARAM(1)(sp) # int *threads_starting
 140         std r5,STACK_FRAME_PARAM(2)(sp) # int *running
 141
 142         // Load FPRs with expected values
 143         OP_REGS lfd, 8, 0, 31, r3
 144
 145         sync
 146         # Atomic DEC
 147         ld r3,STACK_FRAME_PARAM(1)(sp)
 148 1:      lwarx r4,0,r3
 149         addi r4,r4,-1
 150         stwcx. r4,0,r3
 151         bne- 1b
 152
 153 2:      ld r3,STACK_FRAME_PARAM(0)(sp)
 154         bl check_all_fprs
 155         cmpdi r3,0
 156         bne 3f
 157         ld r4,STACK_FRAME_PARAM(2)(sp)
 158         ld r5,0(r4)
 159         cmpwi r5,0
 160         bne 2b
 161
 162 3:      POP_FPU(256)
 163         POP_BASIC_STACK(256)
 164         blr
 165 FUNC_END(preempt_fpu)