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 "gpr_asm.h"
8#include "fpu_asm.h"
9#include "vmx_asm.h"
10#include "vsx_asm.h"
11
12/*
13 * Large caveat here being that the caller cannot expect the
14 * signal to always be sent! The hardware can (AND WILL!) abort
15 * the transaction between the tbegin and the tsuspend (however
16 * unlikely it seems or infrequently it actually happens).
17 * You have been warned.
18 */
19/* long tm_signal_self(pid_t pid, long *gprs, double *fps, vector *vms, vector *vss); */
20FUNC_START(tm_signal_self_context_load)
21 PUSH_BASIC_STACK(512)
22 /*
23 * Don't strictly need to save and restore as it depends on if
24 * we're going to use them, however this reduces messy logic
25 */
26 PUSH_VMX(STACK_FRAME_LOCAL(5,0),r8)
27 PUSH_FPU(512)
28 PUSH_NVREGS_BELOW_FPU(512)
29 std r3, STACK_FRAME_PARAM(0)(sp) /* pid */
30 std r4, STACK_FRAME_PARAM(1)(sp) /* gps */
31 std r5, STACK_FRAME_PARAM(2)(sp) /* fps */
32 std r6, STACK_FRAME_PARAM(3)(sp) /* vms */
33 std r7, STACK_FRAME_PARAM(4)(sp) /* vss */
34
35 ld r3, STACK_FRAME_PARAM(1)(sp)
36 cmpdi r3, 0
37 beq skip_gpr_lc
38 bl load_gpr
39skip_gpr_lc:
40 ld r3, STACK_FRAME_PARAM(2)(sp)
41 cmpdi r3, 0
42 beq skip_fpu_lc
43 bl load_fpu
44skip_fpu_lc:
45 ld r3, STACK_FRAME_PARAM(3)(sp)
46 cmpdi r3, 0
47 beq skip_vmx_lc
48 bl load_vmx
49skip_vmx_lc:
50 ld r3, STACK_FRAME_PARAM(4)(sp)
51 cmpdi r3, 0
52 beq skip_vsx_lc
53 bl load_vsx
54skip_vsx_lc:
55 /*
56 * Set r3 (return value) before tbegin. Use the pid as a known
57 * 'all good' return value, zero is used to indicate a non-doomed
58 * transaction.
59 */
60 ld r3, STACK_FRAME_PARAM(0)(sp)
61 tbegin.
62 beq 1f
63 tsuspend. /* Can't enter a syscall transactionally */
64 ld r3, STACK_FRAME_PARAM(1)(sp)
65 cmpdi r3, 0
66 beq skip_gpr_lt
67 /* Get the second half of the array */
68 addi r3, r3, 8 * 18
69 bl load_gpr
70skip_gpr_lt:
71 ld r3, STACK_FRAME_PARAM(2)(sp)
72 cmpdi r3, 0
73 beq skip_fpu_lt
74 /* Get the second half of the array */
75 addi r3, r3, 8 * 18
76 bl load_fpu
77skip_fpu_lt:
78 ld r3, STACK_FRAME_PARAM(3)(sp)
79 cmpdi r3, 0
80 beq skip_vmx_lt
81 /* Get the second half of the array */
82 addi r3, r3, 16 * 12
83 bl load_vmx
84skip_vmx_lt:
85 ld r3, STACK_FRAME_PARAM(4)(sp)
86 cmpdi r3, 0
87 beq skip_vsx_lt
88 /* Get the second half of the array */
89 addi r3, r3, 16 * 12
90 bl load_vsx
91skip_vsx_lt:
92 li r0, 37 /* sys_kill */
93 ld r3, STACK_FRAME_PARAM(0)(sp) /* pid */
94 li r4, 10 /* SIGUSR1 */
95 sc /* Taking the signal will doom the transaction */
96 tabort. 0
97 tresume. /* Be super sure we abort */
98 /*
99 * This will cause us to resume doomed transaction and cause
100 * hardware to cleanup, we'll end up at 1: anything between
101 * tresume. and 1: shouldn't ever run.
102 */
103 li r3, 0
104 1:
105 POP_VMX(STACK_FRAME_LOCAL(5,0),r4)
106 POP_FPU(512)
107 POP_NVREGS_BELOW_FPU(512)
108 POP_BASIC_STACK(512)
109 blr
110FUNC_END(tm_signal_self_context_load)
111

source code of linux/tools/testing/selftests/powerpc/tm/tm-signal.S