kernel/fiasco/src/kern/ppc32/context-ppc32.cpp

   1 IMPLEMENTATION [ppc32]:
   2
   3 /** Note: TCB pointer is located in sprg1 */
   4
   5 /*
   6 #include <cassert>
   7 #include <cstdio>
   8
   9 #include "l4_types.h"
  10 #include "cpu_lock.h"
  11 #include "lock_guard.h"
  12 #include "space.h"
  13 #include "thread_state.h"
  14 */
  15
  16 #include "kmem.h"
  17 #include "utcb_support.h"
  18
  19 IMPLEMENT inline
  20 void
  21 Context::spill_user_state()
  22 {}
  23
  24 IMPLEMENT inline
  25 void
  26 Context::fill_user_state()
  27 {}
  28
  29 PUBLIC inline
  30 Utcb *
  31 Context::access_utcb() const
  32 { return utcb(); }
  33
  34 PUBLIC inline
  35 Vcpu_state *
  36 Context::access_vcpu(bool = false) const
  37 { return vcpu_state(); }
  38
  39 IMPLEMENT inline
  40 void
  41 Context::switch_cpu(Context *t)
  42 {
  43   unsigned long dummy1, dummy2, dummy3;
  44
  45 //  printf("Switch %p -> %p (sp %p -> %p)\n", this, t, _kernel_sp, t->_kernel_sp);
  46 #warning FIXIT: switchin_context_label needs a Context* parameter (old Context *)
  47   asm volatile (" lis    %%r5, 1f@ha                \n"
  48                 " addi   %%r5, %%r5, 1f@l           \n"
  49
  50                 //save return addr
  51                 " stw    %%r5, 0(%%r1)              \n"
  52                 " stw    %%r1, 0(%[kernel_sp])      \n"
  53
  54                 //switch stack
  55                 " mr     %%r1, %[new_sp]            \n"
  56                 " mr     %%r3, %[new_thread]        \n"
  57
  58                 //address space switch
  59                 " bl     switchin_context_label     \n"
  60                 " lwz    %%r5, 0(%%r1)              \n"
  61                 " mtctr  %%r5                       \n"
  62                 " bctr                              \n"
  63                 "1:                                 \n"
  64                 : [new_thread]"=r" (dummy1),
  65                   [kernel_sp] "=r" (dummy2),
  66                   [new_sp]    "=r" (dummy3)
  67                 : "0" (t),
  68                   "1" (&_kernel_sp),
  69                   "2" (t->_kernel_sp)
  70                 : "r0",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
  71                   "r8",  "r9",  "r13", "r14", "r15", "r16", "r17",
  72                   "r18", "r19", "r20", "r21", "r22", "r23", "r24",
  73                   "r25", "r26", "r27", "r28", "r29", "r30", "r31",
  74                   "ctr", "lr",  "cr2", "cr3", "cr4", "xer", "memory"
  75                   );
  76 }
  77
  78 /** Thread context switchin.  Called on every re-activation of a
  79     thread (switch_exec()).  This method is public only because it is
  80     called by an ``extern "C"'' function that is called
  81     from assembly code (call_switchin_context).
  82  */
  83
  84 IMPLEMENT
  85 void Context::switchin_context(Context *from)
  86 {
  87   assert(this == current());
  88   assert(state() & Thread_ready);
  89   // Set kernel-esp in case we want to return to the user.
  90   // kmem::kernel_esp() returns a pointer to the kernel SP (in the
  91   // TSS) the CPU uses when next switching from user to kernel mode.
  92   // regs() + 1 returns a pointer to the end of our kernel stack.
  93   Kmem::kernel_sp( reinterpret_cast<Mword*>(regs() + 1) );
  94 #if 0
  95   printf("switch in address space: %p\n",_space);
  96 #endif
  97
  98   // switch to our page directory if nessecary
  99   vcpu_aware_space()->switchin_context(from->vcpu_aware_space());
 100
 101   Utcb_support::current((Utcb*)local_id());
 102 }