1 // Copyright 2019 The Marl Authors.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #if defined(__powerpc64__)
16
17 #include "osfiber_asm_ppc64.h"
18
19 #include "marl/export.h"
20
21 MARL_EXPORT
marl_fiber_trampoline(void (* target)(void *),void * arg)22 void marl_fiber_trampoline(void (*target)(void*), void* arg) {
23 target(arg);
24 }
25
26 MARL_EXPORT
marl_fiber_set_target(struct marl_fiber_context * ctx,void * stack,uint32_t stack_size,void (* target)(void *),void * arg)27 void marl_fiber_set_target(struct marl_fiber_context* ctx,
28 void* stack,
29 uint32_t stack_size,
30 void (*target)(void*),
31 void* arg) {
32 uintptr_t stack_top = (uintptr_t)((uint8_t*)(stack) + stack_size);
33 if ((stack_top % 16) != 0) {
34 stack_top -= (stack_top % 16);
35 }
36
37 // Write a backchain and subtract a minimum stack frame size (32)
38 *(uintptr_t*)stack_top = 0;
39 stack_top -= 32;
40 *(uintptr_t*)stack_top = stack_top + 32;
41
42 // Load registers
43 ctx->r1 = stack_top;
44 ctx->lr = (uintptr_t)marl_fiber_trampoline;
45 ctx->r3 = (uintptr_t)target;
46 ctx->r4 = (uintptr_t)arg;
47
48 // Thread pointer must be saved in r13
49 __asm__ volatile("mr %0, 13\n" : "=r"(ctx->r13));
50 }
51
52 #endif // __powerpc64__
53