Add PS2 libco

libretro-common/libco/libco.c

@@ -29,6 +29,8 @@ void genode_free_secondary_stack(void *stack);
     #include "ppc.c"
   #elif defined(__aarch64__)
     #include "aarch64.c"
+  #elif defined(PS2)
+    #include "ps2.c"
   #elif defined(PSP)
     #include "psp1.c"
   #elif defined VITA

libretro-common/libco/ps2.c

@@ -0,0 +1,66 @@
+#define LIBCO_C
+#include "libco.h"
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <kernel.h>
+
+/* Since cothread_t is a void pointer it must contain an address. We can't return a reference to a local variable
+ * because it would go out of scope, so we create a static variable instead so we can return a reference to it.
+ */
+static int32_t active_thread_id = -1;
+extern void *_gp;
+
+cothread_t co_active()
+{
+  active_thread_id = GetThreadId();
+  return &active_thread_id;
+}
+
+cothread_t co_create(unsigned int size, void (*entrypoint)(void))
+{
+  /* Similar scenario as with active_thread_id except there will only be one active_thread_id while there could be many
+   * new threads each with their own handle, so we create them on the heap instead and delete them manually when they're
+   * no longer needed in co_delete().
+   */
+  cothread_t handle = malloc(sizeof(cothread_t));
+  ee_thread_t thread;
+
+  // u8 threadStack[size/8] __attribute__ ((aligned(16)));
+  void *threadStack = (void *)malloc(size);
+
+  if ( threadStack== NULL)
+	{
+		printf("libco: ERROR: creating threadStack\n");
+		return(-1);
+	}
+
+	thread.stack_size		= size;
+	thread.gp_reg			= &_gp;
+	thread.func				= (void *)entrypoint;
+	thread.stack			= threadStack;
+	thread.option			= 0;
+  thread.initial_priority = 1;
+
+  int32_t new_thread_id = CreateThread(&thread);
+	if (new_thread_id < 0)
+		printf("libco: ERROR: creating thread\n");
+
+  StartThread(new_thread_id, NULL);
+  *(uint32_t *)handle = new_thread_id;
+  return handle;
+}
+
+void co_delete(cothread_t handle)
+{
+  TerminateThread(*(uint32_t *)handle);
+	DeleteThread(*(uint32_t *)handle);
+  free(handle);
+}
+
+void co_switch(cothread_t handle)
+{
+  WakeupThread(*(uint32_t *)handle);
+  /* Sleep the currently active thread so the new thread can start */
+  SleepThread();
+}