kernel/fiasco/src/kern/arm/timer-arm-mptimer.cpp

   1 // --------------------------------------------------------------------------
   2 INTERFACE [arm && mptimer]:
   3
   4 #include "kmem.h"
   5 #include "cpu.h"
   6
   7 EXTENSION class Timer
   8 {
   9 public:
  10   static unsigned irq() { return 29; }
  11
  12 private:
  13   typedef Mmio_register_block Mp_timer;
  14
  15   enum
  16   {
  17     Timer_load_reg     = 0x600 + 0x0,
  18     Timer_counter_reg  = 0x600 + 0x4,
  19     Timer_control_reg  = 0x600 + 0x8,
  20     Timer_int_stat_reg = 0x600 + 0xc,
  21
  22     Prescaler = 0,
  23
  24     Timer_control_enable    = 1 << 0,
  25     Timer_control_reload    = 1 << 1,
  26     Timer_control_itenable  = 1 << 2,
  27     Timer_control_prescaler = (Prescaler & 0xff) << 8,
  28
  29     Timer_int_stat_event   = 1,
  30   };
  31 };
  32
  33 // --------------------------------------------------------------
  34 IMPLEMENTATION [arm && mptimer]:
  35
  36 #include <cstdio>
  37 #include "config.h"
  38 #include "kip.h"
  39
  40 #include "globals.h"
  41
  42 PRIVATE static
  43 Mword
  44 Timer::start_as_counter()
  45 {
  46   static_assert(Scu::Available, "No SCU available in this configuration");
  47
  48   Cpu::scu->write<Mword>(Timer_control_prescaler | Timer_control_reload
  49                          | Timer_control_enable,
  50                          Timer_control_reg);
  51
  52   Mword v = ~0UL;
  53   Cpu::scu->write<Mword>(v, Timer_counter_reg);
  54   return v;
  55 }
  56
  57 PRIVATE static
  58 Mword
  59 Timer::stop_counter()
  60 {
  61   Mword v = Cpu::scu->read<Mword>(Timer_counter_reg);
  62   Cpu::scu->write<Mword>(0, Timer_control_reg);
  63   return v;
  64 }
  65
  66 IMPLEMENT
  67 void
  68 Timer::init(Cpu_number)
  69 {
  70
  71   Mword i = interval();
  72
  73   Cpu::scu->write<Mword>(i, Timer_load_reg);
  74   Cpu::scu->write<Mword>(i, Timer_counter_reg);
  75   Cpu::scu->write<Mword>(Timer_control_prescaler | Timer_control_reload
  76                          | Timer_control_enable | Timer_control_itenable,
  77                          Timer_control_reg);
  78 }
  79
  80 static inline
  81 Unsigned64
  82 Timer::timer_to_us(Unsigned32 /*cr*/)
  83 { return 0; }
  84
  85 static inline
  86 Unsigned64
  87 Timer::us_to_timer(Unsigned64 us)
  88 { (void)us; return 0; }
  89
  90 PUBLIC static inline
  91 void
  92 Timer::acknowledge()
  93 {
  94   Cpu::scu->write<Mword>(Timer_int_stat_event, Timer_int_stat_reg);
  95 }
  96
  97 IMPLEMENT inline
  98 void
  99 Timer::update_one_shot(Unsigned64 wakeup)
 100 {
 101   (void)wakeup;
 102 }
 103
 104 IMPLEMENT inline NEEDS["config.h", "kip.h"]
 105 Unsigned64
 106 Timer::system_clock()
 107 {
 108   if (Config::Scheduler_one_shot)
 109     return 0;
 110   return Kip::k()->clock;
 111 }