| 1 | /* |
| 2 | libco.arm (2015-06-18) |
| 3 | license: public domain |
| 4 | */ |
| 5 | |
| 6 | #define LIBCO_C |
| 7 | #include "libco.h" |
| 8 | |
| 9 | #include <assert.h> |
| 10 | #include <stdlib.h> |
| 11 | #include <unistd.h> |
| 12 | #include <psp2/kernel/sysmem.h> |
| 13 | #include <stdio.h> |
| 14 | #include <string.h> |
| 15 | |
| 16 | #define FOUR_KB_ALIGN(x) align(x, 12) |
| 17 | #define MB_ALIGN(x) align(x, 20) |
| 18 | |
| 19 | #ifdef __cplusplus |
| 20 | extern "C" { |
| 21 | #endif |
| 22 | |
| 23 | static inline int align(int x, int n) |
| 24 | { |
| 25 | return (((x >> n) + 1) << n); |
| 26 | } |
| 27 | |
| 28 | static thread_local unsigned long co_active_buffer[64]; |
| 29 | static thread_local cothread_t co_active_handle = 0; |
| 30 | static void(*co_swap)(cothread_t, cothread_t) = 0; |
| 31 | static int block; |
| 32 | static uint32_t co_swap_function[] = { |
| 33 | 0xe8a16ff0, /* stmia r1!, {r4-r11,sp,lr} */ |
| 34 | 0xe8b0aff0, /* ldmia r0!, {r4-r11,sp,pc} */ |
| 35 | 0xe12fff1e, /* bx lr */ |
| 36 | }; |
| 37 | |
| 38 | static void co_init(void) |
| 39 | { |
| 40 | int ret; |
| 41 | void *base; |
| 42 | |
| 43 | block = sceKernelAllocMemBlockForVM("libco", |
| 44 | MB_ALIGN(FOUR_KB_ALIGN(sizeof co_swap_function))); |
| 45 | if (block < 0) |
| 46 | return; |
| 47 | |
| 48 | /* Get base address */ |
| 49 | if ((ret = sceKernelGetMemBlockBase(block, &base)) < 0) |
| 50 | return; |
| 51 | |
| 52 | /* Set domain to be writable by user */ |
| 53 | if ((ret = sceKernelOpenVMDomain()) < 0) |
| 54 | return; |
| 55 | |
| 56 | memcpy(base, co_swap_function, sizeof co_swap_function); |
| 57 | |
| 58 | /* Set domain back to read-only */ |
| 59 | if ((ret = sceKernelCloseVMDomain()) < 0) |
| 60 | return; |
| 61 | |
| 62 | /* Flush icache */ |
| 63 | ret = sceKernelSyncVMDomain(block, base, |
| 64 | MB_ALIGN(FOUR_KB_ALIGN(sizeof co_swap_function))); |
| 65 | if (ret < 0) |
| 66 | return; |
| 67 | |
| 68 | co_swap = (void(*)(cothread_t, cothread_t))base; |
| 69 | } |
| 70 | |
| 71 | cothread_t co_active(void) |
| 72 | { |
| 73 | if (!co_active_handle) |
| 74 | co_active_handle = &co_active_buffer; |
| 75 | return co_active_handle; |
| 76 | } |
| 77 | |
| 78 | cothread_t co_create(unsigned int size, void(*entrypoint)(void)) |
| 79 | { |
| 80 | unsigned long* handle = 0; |
| 81 | if (!co_swap) |
| 82 | co_init(); |
| 83 | if (!co_active_handle) |
| 84 | co_active_handle = &co_active_buffer; |
| 85 | size += 256; |
| 86 | size &= ~15; |
| 87 | |
| 88 | if ((handle = (unsigned long*)malloc(size))) |
| 89 | { |
| 90 | unsigned long *p = (unsigned long*)((unsigned char*)handle + size); |
| 91 | handle[8] = (unsigned long)p; |
| 92 | handle[9] = (unsigned long)entrypoint; |
| 93 | } |
| 94 | |
| 95 | return handle; |
| 96 | } |
| 97 | |
| 98 | void co_delete(cothread_t handle) |
| 99 | { |
| 100 | free(handle); |
| 101 | sceKernelFreeMemBlock(block); |
| 102 | } |
| 103 | |
| 104 | void co_switch(cothread_t handle) |
| 105 | { |
| 106 | cothread_t co_previous_handle = co_active_handle; |
| 107 | co_swap(co_active_handle = handle, co_previous_handle); |
| 108 | } |
| 109 | |
| 110 | #ifdef __cplusplus |
| 111 | } |
| 112 | #endif |