arch/arm-raspi/timer/timer_init.c

   1 /*
   2     Copyright © 2013-2015, 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, last_CHI;
  38
  39     D(bug("[Timer] Timer1Tick()\n"));
  40
  41     if (!(TimerBase) || !(SysBase))
  42     {
  43         bug("[Timer] Timer1Tick: Bad Params!\n");
  44         return;
  45     }
  46
  47     last_CHI = TimerBase->tb_Platform.tbp_CHI;
  48     last_CLO = TimerBase->tb_Platform.tbp_CLO;
  49
  50     /* Aknowledge and update our timer interrupt */
  51     *((volatile unsigned int *)(SYSTIMER_CS)) = (1 << TICK_TIMER); //TimerBase->tb_Platform.tbp_cs;
  52     TimerBase->tb_Platform.tbp_CHI = *((volatile unsigned int *)(SYSTIMER_CHI));
  53     TimerBase->tb_Platform.tbp_CLO = *((volatile unsigned int *)(SYSTIMER_CLO));
  54
  55     D(bug("[Timer] Timer1Tick: Updating EClock..\n"));
  56     D(bug("[Timer] Timer1Tick:   diff_CHI = %d\n", (TimerBase->tb_Platform.tbp_CHI - last_CHI)));
  57     D(bug("[Timer] Timer1Tick:   diff_CLO = %d\n", (TimerBase->tb_Platform.tbp_CLO - last_CLO)));
  58
  59     TimerBase->tb_Platform.tbp_TickRate.tv_secs  = 0;
  60     if ((TimerBase->tb_Platform.tbp_CLO - last_CLO) > 0)
  61         TimerBase->tb_Platform.tbp_TickRate.tv_micro = TimerBase->tb_Platform.tbp_CLO - last_CLO;
  62     else
  63         TimerBase->tb_Platform.tbp_TickRate.tv_micro = ((1000000 - last_CLO) + TimerBase->tb_Platform.tbp_CLO);
  64
  65     /* Increment EClock value and process microhz requests */
  66     ADDTIME(&TimerBase->tb_CurrentTime, &TimerBase->tb_Platform.tbp_TickRate);
  67     ADDTIME(&TimerBase->tb_Elapsed, &TimerBase->tb_Platform.tbp_TickRate);
  68     TimerBase->tb_ticks_total++;
  69
  70     D(bug("[Timer] Timer1Tick: Processing events.. \n"));
  71
  72     handleMicroHZ(TimerBase, SysBase);
  73 //    handleEClock(TimerBase, SysBase);
  74
  75     D(bug("[Timer] Timer1Tick: Reconfiguring interrupt..\n"));
  76
  77     TimerBase->tb_Platform.tbp_CLO = *((volatile unsigned int *)(SYSTIMER_CLO));
  78     *((volatile unsigned int *)(SYSTIMER_C0 + (TICK_TIMER * 4))) = (TimerBase->tb_Platform.tbp_CLO + (1000000 / TimerBase->tb_eclock_rate));
  79
  80     D(bug("[Timer] Timer1Tick: Done..\n"));
  81 }
  82
  83 /****************************************************************************************/
  84 int vblank_Init(struct TimerBase *LIBBASE);
  85
  86 static int Timer_Init(struct TimerBase *TimerBase)
  87 {
  88     D(bug("[Timer] Timer_Init: kernel.resource @ 0x%p\n", KernelBase));
  89
  90     TimerBase->tb_Platform.tbp_periiobase = KrnGetSystemAttr(KATTR_PeripheralBase);
  91
  92     /* Install timer IRQ handler */
  93     TimerBase->tb_TimerIRQHandle = KrnAddIRQHandler(IRQ_TIMER0 + TICK_TIMER, Timer1Tick, TimerBase, SysBase);
  94     if (!TimerBase->tb_TimerIRQHandle)
  95         return FALSE;
  96
  97     D(bug("[Timer] Timer_Init: TimerIRQHandle @ 0x%p\n", TimerBase->tb_TimerIRQHandle));
  98
  99     /* By default we want 100 Hz EClock */
 100     TimerBase->tb_eclock_rate = 100;
 101
 102     /*
 103      * Since we are software-driven, we can just ask the user which
 104      * frequencies he wishes to use.
 105      */
 106     BootLoaderBase = OpenResource("bootloader.resource");
 107     if (BootLoaderBase)
 108     {
 109         struct List *args = GetBootInfo(BL_Args);
 110
 111         if (args)
 112         {
 113             struct Node *node;
 114
 115             for (node = args->lh_Head; node->ln_Succ; node = node->ln_Succ)
 116             {
 117                 if (strncasecmp(node->ln_Name, "eclock=", 7) == 0)
 118                 {
 119                     TimerBase->tb_eclock_rate = atoi(&node->ln_Name[7]);
 120                     break;
 121                 }
 122             }
 123         }
 124     }
 125
 126     /* Set ExecBase public field. */
 127     SysBase->ex_EClockFrequency = TimerBase->tb_eclock_rate;
 128     D(bug("[Timer] Timer frequency is %d\n", TimerBase->tb_eclock_rate));
 129
 130     /* Calculate timer period in us */
 131     TimerBase->tb_Platform.tbp_TickRate.tv_secs  = 0;
 132     TimerBase->tb_Platform.tbp_TickRate.tv_micro = 1000000 / TimerBase->tb_eclock_rate;
 133
 134     /* Start up GPU timer #TICK_TIMER */
 135     Forbid();
 136     TimerBase->tb_Platform.tbp_CHI = *((volatile unsigned int *)(SYSTIMER_CHI));
 137     TimerBase->tb_Platform.tbp_CLO = *((volatile unsigned int *)(SYSTIMER_CLO));
 138     *((volatile unsigned int *)(SYSTIMER_C0 + (TICK_TIMER * 4))) = (TimerBase->tb_Platform.tbp_CLO + TimerBase->tb_Platform.tbp_TickRate.tv_micro);
 139     Permit();
 140
 141     vblank_Init(TimerBase);
 142
 143     D(bug("[Timer] Timer_Init: configured GPU timer %d\n", TICK_TIMER));
 144
 145     return TRUE;
 146 }
 147
 148 static int Timer_Expunge(struct TimerBase *TimerBase)
 149 {
 150     D(bug("[Timer] Timer_Expunge()\n"));
 151
 152     if (TimerBase->tb_TimerIRQHandle)
 153         KrnRemIRQHandler(TimerBase->tb_TimerIRQHandle);
 154
 155     return TRUE;
 156 }
 157
 158 ADD2INITLIB(Timer_Init, 0)
 159 ADD2EXPUNGELIB(Timer_Expunge, 0)