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 FUNC_START(test_fpu) 70 # r3 holds pointer to where to put the result of fork 71 # r4 holds pointer to the pid 72 # f14-f31 are non volatiles 73 PUSH_BASIC_STACK(256) 74 PUSH_FPU(256) 75 std r3,STACK_FRAME_PARAM(0)(sp) # Address of darray 76 std r4,STACK_FRAME_PARAM(1)(sp) # Address of pid 77 78 bl load_fpu 79 nop 80 li r0,__NR_fork 81 sc 82 83 # pass the result of the fork to the caller 84 ld r9,STACK_FRAME_PARAM(1)(sp) 85 std r3,0(r9) 86 87 ld r3,STACK_FRAME_PARAM(0)(sp) 88 bl check_fpu 89 nop 90 91 POP_FPU(256) 92 POP_BASIC_STACK(256) 93 blr 94 FUNC_END(test_fpu) 95 96 # int preempt_fpu(double *darray, int *threads_running, int *running) 97 # On starting will (atomically) decrement not_ready as a signal that the FPU 98 # has been loaded with darray. Will proceed to check the validity of the FPU 99 # registers while running is not zero. 100 FUNC_START(preempt_fpu) 101 PUSH_BASIC_STACK(256) 102 PUSH_FPU(256) 103 std r3,STACK_FRAME_PARAM(0)(sp) # double *darray 104 std r4,STACK_FRAME_PARAM(1)(sp) # int *threads_starting 105 std r5,STACK_FRAME_PARAM(2)(sp) # int *running 106 107 bl load_fpu 108 nop 109 110 sync 111 # Atomic DEC 112 ld r3,STACK_FRAME_PARAM(1)(sp) 113 1: lwarx r4,0,r3 114 addi r4,r4,-1 115 stwcx. r4,0,r3 116 bne- 1b 117 118 2: ld r3,STACK_FRAME_PARAM(0)(sp) 119 bl check_fpu 120 nop 121 cmpdi r3,0 122 bne 3f 123 ld r4,STACK_FRAME_PARAM(2)(sp) 124 ld r5,0(r4) 125 cmpwi r5,0 126 bne 2b 127 128 3: POP_FPU(256) 129 POP_BASIC_STACK(256) 130 blr 131 FUNC_END(preempt_fpu) 132