RetroArch/libretro-common/libco/psp2.c

114 lines
2.6 KiB
C

/*
libco.arm (2015-06-18)
license: public domain
*/
#define LIBCO_C
#include "libco.h"
#include <assert.h>
#include <stdlib.h>
#include <unistd.h>
#include <psp2/kernel/sysmem.h>
#include <stdio.h>
#include <string.h>
#define FOUR_KB_ALIGN(x) align(x, 12)
#define MB_ALIGN(x) align(x, 20)
#ifdef __cplusplus
extern "C" {
#endif
static inline int align(int x, int n)
{
return (((x >> n) + 1) << n);
}
static thread_local unsigned long co_active_buffer[64];
static thread_local cothread_t co_active_handle = 0;
static void(*co_swap)(cothread_t, cothread_t) = 0;
static int block;
static uint32_t co_swap_function[] = {
0xe8a16ff0, /* stmia r1!, {r4-r11,sp,lr} */
0xe8b0aff0, /* ldmia r0!, {r4-r11,sp,pc} */
0xe12fff1e, /* bx lr */
};
static void co_init(void)
{
int ret;
void *base;
block = sceKernelAllocMemBlockForVM("libco",
MB_ALIGN(FOUR_KB_ALIGN(sizeof co_swap_function)));
if (block < 0)
return;
/* get base address */
ret = sceKernelGetMemBlockBase(block, &base);
if (ret < 0)
return;
/* set domain to be writable by user */
ret = sceKernelOpenVMDomain();
if (ret < 0)
return;
memcpy(base, co_swap_function, sizeof co_swap_function);
/* set domain back to read-only */
ret = sceKernelCloseVMDomain();
if (ret < 0)
return;
/* flush icache */
ret = sceKernelSyncVMDomain(block, base,
MB_ALIGN(FOUR_KB_ALIGN(sizeof co_swap_function)));
if (ret < 0)
return;
co_swap = (void(*)(cothread_t, cothread_t))base;
}
cothread_t co_active(void)
{
if (!co_active_handle) co_active_handle = &co_active_buffer;
return co_active_handle;
}
cothread_t co_create(unsigned int size, void(*entrypoint)(void))
{
unsigned long* handle = 0;
if (!co_swap)
co_init();
if (!co_active_handle) co_active_handle = &co_active_buffer;
size += 256;
size &= ~15;
if ((handle = (unsigned long*)malloc(size)))
{
unsigned long* p = (unsigned long*)((unsigned char*)handle + size);
handle[8] = (unsigned long)p;
handle[9] = (unsigned long)entrypoint;
}
return handle;
}
void co_delete(cothread_t handle)
{
free(handle);
sceKernelFreeMemBlock(block);
}
void co_switch(cothread_t handle)
{
cothread_t co_previous_handle = co_active_handle;
co_swap(co_active_handle = handle, co_previous_handle);
}
#ifdef __cplusplus
}
#endif