3 * - By John Hodge (thePowersGang)
6 * - ARM7 Process Switching
9 #include <threads_int.h>
13 extern tThread gThreadZero;
14 extern void SwitchTask(Uint32 NewSP, Uint32 *OldSP, Uint32 NewIP, Uint32 *OldIP, Uint32 MemPtr);
15 extern void KernelThreadHeader(void); // Actually takes args on stack
16 extern void Proc_int_DropToUser(Uint32 IP, Uint32 SP) NORETURN;
17 extern Uint32 Proc_int_SwapUserSP(Uint32 NewSP);
18 extern Uint32 Proc_CloneInt(Uint32 *SP, Uint32 *MemPtr);
19 extern tVAddr MM_NewKStack(int bGlobal); // TODO: Move out into a header
20 extern tVAddr MM_NewUserStack(void);
21 extern char kernel_table0[];
24 void Proc_IdleThread(void *unused);
27 tThread *gpCurrentThread = &gThreadZero;
28 tThread *gpIdleThread = NULL;
31 void ArchThreads_Init(void)
33 gThreadZero.MemState.Base = (tPAddr)&kernel_table0 - KERNEL_BASE;
36 void Proc_IdleThread(void *unused)
38 Threads_SetPriority(gpIdleThread, -1);
41 __asm__ __volatile__ ("wfi");
49 tid = Proc_NewKThread( Proc_IdleThread, NULL );
50 gpIdleThread = Threads_GetThread(tid);
51 gpIdleThread->ThreadName = (char*)"Idle Thread";
59 tThread *Proc_GetCurThread(void)
61 return gpCurrentThread;
64 void Proc_StartUser(Uint Entrypoint, Uint Base, int ArgC, char **ArgV, int DataSize)
71 // Log_Debug("Proc", "Proc_StartUser: (Entrypoint=%p, Base=%p, ArgC=%i, ArgV=%p, DataSize=0x%x)",
72 // Entrypoint, Base, ArgC, ArgV, DataSize);
74 // Write data to the user's stack
75 usr_sp = (void*)MM_NewUserStack();
76 usr_sp -= (DataSize+3)/4;
77 memcpy(usr_sp, ArgV, DataSize);
80 // Adjust user's copy of the arguments
81 delta = (tVAddr)usr_sp - (tVAddr)ArgV;
83 for(i = 0; ArgV[i]; i ++) ArgV[i] += delta;
85 for(i = 0; envp[i]; i ++) envp[i] += delta;
87 *--usr_sp = (Uint32)envp;
88 *--usr_sp = (Uint32)ArgV;
89 *--usr_sp = (Uint32)ArgC;
93 Log_Debug("Proc", "Proc_int_DropToUser(%p, %p)", Entrypoint, usr_sp);
95 // Needed to get around relocation truncation
97 void (*drop)(Uint32, Uint32) NORETURN = Proc_int_DropToUser;
98 drop(Entrypoint, (Uint32)usr_sp);
102 tTID Proc_Clone(Uint Flags)
107 new = Threads_CloneTCB(Flags);
110 // Actual clone magic
111 pc = Proc_CloneInt(&sp, &mem);
113 Log("Proc_Clone: In child");
117 new->SavedState.IP = pc;
118 new->SavedState.SP = sp;
119 new->SavedState.UserSP = Proc_int_SwapUserSP(0);
120 new->SavedState.UserIP = Proc_GetCurThread()->SavedState.UserIP;
121 new->MemState.Base = mem;
123 Threads_AddActive(new);
128 tTID Proc_SpawnWorker( void (*Fnc)(void*), void *Ptr )
133 new = Threads_CloneThreadZero();
135 if(new->ThreadName) free(new->ThreadName);
136 new->ThreadName = NULL;
138 new->KernelStack = MM_NewKStack(1);
139 if(!new->KernelStack) {
140 // TODO: Delete thread
141 Log_Error("Proc", "Unable to allocate kernel stack");
145 sp = new->KernelStack;
147 *(Uint32*)(sp -= 4) = (Uint)Ptr;
148 *(Uint32*)(sp -= 4) = (Uint)Fnc;
149 *(Uint32*)(sp -= 4) = (Uint)new;
151 new->SavedState.SP = sp;
152 new->SavedState.IP = (Uint)KernelThreadHeader;
154 Threads_AddActive(new);
159 tTID Proc_NewKThread( void (*Fnc)(void*), void *Ptr )
164 new = Threads_CloneTCB(0);
166 free(new->ThreadName);
167 new->ThreadName = NULL;
169 // TODO: Non-shared stack
170 new->KernelStack = MM_NewKStack(1);
171 if(!new->KernelStack) {
172 // TODO: Delete thread
173 Log_Error("Proc", "Unable to allocate kernel stack");
177 sp = new->KernelStack;
179 *(Uint32*)(sp -= 4) = (Uint)Ptr;
180 *(Uint32*)(sp -= 4) = (Uint)Fnc;
181 *(Uint32*)(sp -= 4) = (Uint)new;
183 new->SavedState.SP = sp;
184 new->SavedState.IP = (Uint)KernelThreadHeader;
186 Threads_AddActive(new);
191 void Proc_CallFaultHandler(tThread *Thread)
196 void Proc_Reschedule(void)
200 cur = gpCurrentThread;
202 next = Threads_GetNextToRun(0, cur);
203 if(!next) next = gpIdleThread;
204 if(!next || next == cur) return;
206 Log("Switching to %p (%i %s) IP=%p SP=%p TTBR0=%p UsrSP=%p",
207 next, next->TID, next->ThreadName,
208 next->SavedState.IP, next->SavedState.SP, next->MemState.Base,
209 next->SavedState.UserSP
211 Log("Requested by %p", __builtin_return_address(0));
213 gpCurrentThread = next;
215 cur->SavedState.UserSP = Proc_int_SwapUserSP( next->SavedState.UserSP );
218 next->SavedState.SP, &cur->SavedState.SP,
219 next->SavedState.IP, &cur->SavedState.IP,
225 void Proc_DumpThreadCPUState(tThread *Thread)