kernel/fiasco/src/kern/arm/bsp/pxa-sa/timer-arm-pxa_sa1100.cpp

   1 // ------------------------------------------------------------------------
   2 INTERFACE [arm && (sa1100 || pxa)]:
   3
   4 #include "kmem.h"
   5
   6 EXTENSION class Timer
   7 {
   8 public:
   9   static unsigned irq() { return 26; }
  10
  11 private:
  12   enum {
  13     OSMR0 = Kmem::Timer_map_base + 0x00,
  14     OSMR1 = Kmem::Timer_map_base + 0x04,
  15     OSMR2 = Kmem::Timer_map_base + 0x08,
  16     OSMR3 = Kmem::Timer_map_base + 0x0c,
  17     OSCR  = Kmem::Timer_map_base + 0x10,
  18     OSSR  = Kmem::Timer_map_base + 0x14,
  19     OWER  = Kmem::Timer_map_base + 0x18,
  20     OIER  = Kmem::Timer_map_base + 0x1c,
  21
  22     Timer_diff = (36864 * Config::Scheduler_granularity) / 10000, // 36864MHz*1ms
  23   };
  24 };
  25
  26
  27 // -------------------------------------------------------------
  28 IMPLEMENTATION [arm && (sa1100 || pxa)]:
  29
  30 #include "config.h"
  31 #include "kip.h"
  32 #include "pic.h"
  33 #include "io.h"
  34
  35 IMPLEMENT
  36 void Timer::init(unsigned)
  37 {
  38   Io::write(1,          OIER); // enable OSMR0
  39   Io::write(0,          OWER); // disable Watchdog
  40   Io::write<Mword>(Timer_diff, OSMR0);
  41   Io::write(0,          OSCR); // set timer counter to zero
  42   Io::write(~0U,        OSSR); // clear all status bits
  43 }
  44
  45 static inline
  46 Unsigned64
  47 Timer::timer_to_us(Unsigned32 cr)
  48 { return (((Unsigned64)cr) << 14) / 60398; }
  49
  50 static inline
  51 Unsigned64
  52 Timer::us_to_timer(Unsigned64 us)
  53 { return (us * 60398) >> 14; }
  54
  55 PUBLIC static inline NEEDS["io.h", "config.h", Timer::timer_to_us]
  56 void
  57 Timer::acknowledge()
  58 {
  59   if (Config::Scheduler_one_shot)
  60     {
  61       Kip::k()->clock += timer_to_us(Io::read<Unsigned32>(OSCR));
  62       //puts("Reset timer");
  63       Io::write(0, OSCR);
  64       Io::write(0xffffffff, OSMR0);
  65     }
  66   else
  67     Io::write(0, OSCR);
  68   Io::write(1, OSSR); // clear all status bits
  69
  70   // hmmm?
  71   //enable();
  72 }
  73
  74 IMPLEMENT inline NEEDS["kip.h", "io.h", Timer::timer_to_us, Timer::us_to_timer]
  75 void
  76 Timer::update_one_shot(Unsigned64 wakeup)
  77 {
  78   Unsigned32 apic;
  79   Kip::k()->clock += timer_to_us(Io::read<Unsigned32>(OSCR));
  80   Io::write(0, OSCR);
  81   Unsigned64 now = Kip::k()->clock;
  82
  83   if (EXPECT_FALSE (wakeup <= now) )
  84     // already expired
  85     apic = 1;
  86   else
  87     {
  88       apic = us_to_timer(wakeup - now);
  89       if (EXPECT_FALSE(apic > 0x0ffffffff))
  90         apic = 0x0ffffffff;
  91       if (EXPECT_FALSE (apic < 1) )
  92         // timeout too small
  93         apic = 1;
  94     }
  95
  96   //printf("%15lld: Set Timer to %lld [%08x]\n", now, wakeup, apic);
  97
  98   Io::write(apic, OSMR0);
  99   Io::write(1, OSSR); // clear all status bits
 100 }
 101
 102 IMPLEMENT inline NEEDS["config.h", "kip.h", "io.h", Timer::timer_to_us]
 103 Unsigned64
 104 Timer::system_clock()
 105 {
 106   if (Config::Scheduler_one_shot)
 107     return Kip::k()->clock + timer_to_us(Io::read<Unsigned32>(OSCR));
 108   else
 109     return Kip::k()->clock;
 110 }