arch/ppc-sam440/kernel/kernel_cpu.c

   1 /*
   2     Copyright © 1995-2012, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <aros/debug.h>
   7
   8 #include <asm/amcc440.h>
   9 #include <aros/kernel.h>
  10 #include <aros/libcall.h>
  11 #include <exec/execbase.h>
  12 #include <hardware/intbits.h>
  13
  14 #include "etask.h"
  15
  16 #include "kernel_intern.h"
  17 #include "kernel_cpu.h"
  18 #include "kernel_syscall.h"
  19 #include "kernel_scheduler.h"
  20 #include "kernel_intr.h"
  21
  22 #include <strings.h>
  23
  24 /*
  25  * Task dispatcher. Basically it may be the same one no matter what scheduling algorithm is used
  26  */
  27 void cpu_Dispatch(context_t *regs)
  28 {
  29     struct Task *task;
  30     uint64_t idle;
  31     extern uint64_t idle_time;
  32
  33     __asm__ __volatile__("wrteei 0;");
  34     idle = mftbu();
  35
  36     /*
  37      * Is the list of ready tasks empty? Well, increment the idle switch cound and halt CPU.
  38      * It should be extended by some plugin mechanism which would put CPU and whole machine
  39      * into some more sophisticated sleep states (ACPI?)
  40      */
  41
  42     while (!(task = core_Dispatch())) {
  43         wrmsr(rdmsr() | MSR_POW | MSR_EE);
  44         __asm__ __volatile__("sync; isync;");
  45         __asm__ __volatile__("wrteei 0");
  46         idle_time += mftbu() - idle;
  47
  48         if (SysBase->SysFlags & SFF_SoftInt)
  49             core_Cause(INTB_SOFTINT, 1l << INTB_SOFTINT);
  50     }
  51
  52     /* Restore the task's state */
  53     CopyMem(task->tc_UnionETask.tc_ETask->et_RegFrame, regs, sizeof(regs_t));
  54     regs->cpu.gpr[1] = (IPTR)task->tc_SPReg;
  55
  56     /* Handle tasks's flags */
  57     if (task->tc_Flags & TF_EXCEPT)
  58         Exception();
  59
  60     /* Store the launch time */
  61     GetIntETask(task)->iet_private1 = mftbu();
  62
  63     if (task->tc_Flags & TF_LAUNCH)
  64     {
  65         AROS_UFC1(void, task->tc_Launch,
  66                   AROS_UFCA(struct ExecBase *, SysBase, A6));
  67     }
  68
  69     /* Copy the fpu, mmx, xmm state */
  70 // FIXME: Change to the lazy saving of the FPU state!!!!
  71
  72     regs->cpu.srr1 |= MSR_EE;
  73 }
  74
  75 void cpu_Switch(context_t *regs)
  76 {
  77     struct Task *task;
  78
  79     /* Disable interrupts until the task switch */
  80     __asm__ __volatile__("wrteei 0");
  81
  82     task = SysBase->ThisTask;
  83
  84     /* Copy current task's context into the ETask structure */
  85     memmove(task->tc_UnionETask.tc_ETask->et_RegFrame, regs, sizeof(context_t));
  86
  87     /* Copy the fpu, mmx, xmm state */
  88 // FIXME: Change to the lazy saving of the FPU state!!!!
  89
  90     task->tc_SPReg = (APTR)regs->cpu.gpr[1];
  91
  92     core_Switch();
  93 }