arch/arm-raspi/timer/timer_init.c

   1 /*
   2     Copyright © 2013-2019, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 /*
   7  * RasPi timer driver.
   8  *
   9  * We use the GPU Timer #1 to handle EClock updates, since GPU Timer #3 is used for VBlank,
  10  * and Timers #0 and #2 are used by the GPU itself.
  11  *
  12  */
  13
  14 #define DEBUG 0
  15
  16 #include <aros/bootloader.h>
  17 #include <aros/debug.h>
  18 #include <aros/symbolsets.h>
  19 #include <exec/execbase.h>
  20 #include <exec/interrupts.h>
  21 #include <hardware/intbits.h>
  22 #include <proto/arossupport.h>
  23 #include <proto/bootloader.h>
  24 #include <proto/exec.h>
  25 #include <proto/kernel.h>
  26
  27
  28 #include "timer_intern.h"
  29 #include "timer_macros.h"
  30
  31 #include <stdlib.h>
  32 #include <string.h>
  33
  34 /* Timer 1 (EClock) interrupt handler */
  35 static void Timer1Tick(struct TimerBase *TimerBase, struct ExecBase *SysBase)
  36 {
  37     unsigned int last_CLO;
  38     D(unsigned int last_CHI);
  39
  40     D(bug("[Timer] Timer1Tick()\n"));
  41
  42     if (!(TimerBase) || !(SysBase))
  43     {
  44         bug("[Timer] Timer1Tick: Bad Params!\n");
  45         return;
  46     }
  47
  48     D(last_CHI = TimerBase->tb_Platform.tbp_CHI);
  49     last_CLO = TimerBase->tb_Platform.tbp_CLO;
  50
  51     /* Aknowledge and update our timer interrupt */
  52     *((volatile unsigned int *)(SYSTIMER_CS)) = (1 << TICK_TIMER); //TimerBase->tb_Platform.tbp_cs;
  53     TimerBase->tb_Platform.tbp_CHI = *((volatile unsigned int *)(SYSTIMER_CHI));
  54     TimerBase->tb_Platform.tbp_CLO = *((volatile unsigned int *)(SYSTIMER_CLO));
  55
  56     D(bug("[Timer] Timer1Tick: Updating EClock..\n"));
  57     D(bug("[Timer] Timer1Tick:   diff_CHI = %d\n", (TimerBase->tb_Platform.tbp_CHI - last_CHI)));
  58     D(bug("[Timer] Timer1Tick:   diff_CLO = %d\n", (TimerBase->tb_Platform.tbp_CLO - last_CLO)));
  59
  60     TimerBase->tb_Platform.tbp_TickRate.tv_secs  = 0;
  61     if ((TimerBase->tb_Platform.tbp_CLO - last_CLO) > 0)
  62         TimerBase->tb_Platform.tbp_TickRate.tv_micro = TimerBase->tb_Platform.tbp_CLO - last_CLO;
  63     else
  64         TimerBase->tb_Platform.tbp_TickRate.tv_micro = ((1000000 - last_CLO) + TimerBase->tb_Platform.tbp_CLO);
  65
  66     /* Increment EClock value and process microhz requests */
  67     ADDTIME(&TimerBase->tb_CurrentTime, &TimerBase->tb_Platform.tbp_TickRate);
  68     ADDTIME(&TimerBase->tb_Elapsed, &TimerBase->tb_Platform.tbp_TickRate);
  69     TimerBase->tb_ticks_total++;
  70
  71     D(bug("[Timer] Timer1Tick: Processing events.. \n"));
  72
  73     handleMicroHZ(TimerBase, SysBase);
  74 //    handleEClock(TimerBase, SysBase);
  75
  76     D(bug("[Timer] Timer1Tick: Reconfiguring interrupt..\n"));
  77
  78     TimerBase->tb_Platform.tbp_CLO = *((volatile unsigned int *)(SYSTIMER_CLO));
  79     *((volatile unsigned int *)(SYSTIMER_C0 + (TICK_TIMER * 4))) = (TimerBase->tb_Platform.tbp_CLO + (1000000 / TimerBase->tb_eclock_rate));
  80
  81     D(bug("[Timer] Timer1Tick: Done..\n"));
  82 }
  83
  84 /****************************************************************************************/
  85 int vblank_Init(struct TimerBase *LIBBASE);
  86
  87 static int Timer_Init(struct TimerBase *TimerBase)
  88 {
  89     D(bug("[Timer] Timer_Init: kernel.resource @ 0x%p\n", KernelBase));
  90
  91     TimerBase->tb_Platform.tbp_periiobase = KrnGetSystemAttr(KATTR_PeripheralBase);
  92
  93     /* Install timer IRQ handler */
  94     TimerBase->tb_TimerIRQHandle = KrnAddIRQHandler(IRQ_TIMER0 + TICK_TIMER, Timer1Tick, TimerBase, SysBase);
  95     if (!TimerBase->tb_TimerIRQHandle)
  96         return FALSE;
  97
  98     D(bug("[Timer] Timer_Init: TimerIRQHandle @ 0x%p\n", TimerBase->tb_TimerIRQHandle));
  99
 100     /* By default we want 100 Hz EClock */
 101     TimerBase->tb_eclock_rate = 100;
 102
 103     /*
 104      * Since we are software-driven, we can just ask the user which
 105      * frequencies he wishes to use.
 106      */
 107     BootLoaderBase = OpenResource("bootloader.resource");
 108     if (BootLoaderBase)
 109     {
 110         struct List *args = GetBootInfo(BL_Args);
 111
 112         if (args)
 113         {
 114             struct Node *node;
 115
 116             for (node = args->lh_Head; node->ln_Succ; node = node->ln_Succ)
 117             {
 118                 if (strncasecmp(node->ln_Name, "eclock=", 7) == 0)
 119                 {
 120                     TimerBase->tb_eclock_rate = atoi(&node->ln_Name[7]);
 121                     break;
 122                 }
 123             }
 124         }
 125     }
 126
 127     /* Set ExecBase public field. */
 128     SysBase->ex_EClockFrequency = TimerBase->tb_eclock_rate;
 129     D(bug("[Timer] Timer frequency is %d\n", TimerBase->tb_eclock_rate));
 130
 131     /* Calculate timer period in us */
 132     TimerBase->tb_Platform.tbp_TickRate.tv_secs  = 0;
 133     TimerBase->tb_Platform.tbp_TickRate.tv_micro = 1000000 / TimerBase->tb_eclock_rate;
 134
 135     /* Start up GPU timer #TICK_TIMER */
 136     Forbid();
 137     TimerBase->tb_Platform.tbp_CHI = *((volatile unsigned int *)(SYSTIMER_CHI));
 138     TimerBase->tb_Platform.tbp_CLO = *((volatile unsigned int *)(SYSTIMER_CLO));
 139     *((volatile unsigned int *)(SYSTIMER_C0 + (TICK_TIMER * 4))) = (TimerBase->tb_Platform.tbp_CLO + TimerBase->tb_Platform.tbp_TickRate.tv_micro);
 140     Permit();
 141
 142     vblank_Init(TimerBase);
 143
 144     D(bug("[Timer] Timer_Init: configured GPU timer %d\n", TICK_TIMER));
 145
 146     return TRUE;
 147 }
 148
 149 static int Timer_Expunge(struct TimerBase *TimerBase)
 150 {
 151     D(bug("[Timer] Timer_Expunge()\n"));
 152
 153     if (TimerBase->tb_TimerIRQHandle)
 154         KrnRemIRQHandler(TimerBase->tb_TimerIRQHandle);
 155
 156     return TRUE;
 157 }
 158
 159 ADD2INITLIB(Timer_Init, 0)
 160 ADD2EXPUNGELIB(Timer_Expunge, 0)