KernelLand/Kernel/arch/armv7/platform_realview_pb.c

   1 /*
   2  * Acess2 Kernel ARMv7 Port
   3  * - By John Hodge (thePowersGang)
   4  *
   5  * platform_realviewpb.c
   6  * - RealviewPB core code
   7  */
   8 #include <acess.h>
   9
  10 // === IMPORTS ===
  11 extern tTime    giTimestamp;
  12
  13 // === PROTOTYPES ===
  14 void    Time_Setup(void);       // TODO: Should be in header
  15 void    Time_int_RTCIRQHandler(int IRQ, void *unused);
  16 void    Time_int_TimerIRQHandler(int IRQ, void *unused);
  17 tTime   Time_GetTickOffset(void);       // TODO: Should be in header
  18
  19 // === GLOBALS ===
  20 tTime   giTimeBase;
  21 Uint32  giTime_PartMS;
  22 tPAddr  gGIC_DistributorAddr = 0x1e001000;
  23 tPAddr  gGIC_InterfaceAddr = 0x1e000000;
  24
  25 #define DIVISOR_ENC     1
  26 #define DIVISOR_REAL    (1 << (4*DIVISOR_ENC))
  27 #define TICKS_PER_SECOND        (1000000/DIVISOR_REAL)
  28 #define TICKS_PER_IRQ   (TICKS_PER_SECOND/2)    // Tick twice a second
  29 #define TICKS_PER_MS    (TICKS_PER_SECOND/1000)
  30 #define MS_PER_IRQ      (TICKS_PER_IRQ*1000/TICKS_PER_SECOND)   // (TICKS_PER_IRQ/(TICKS_PER_SECOND/1000))
  31 #define PART_PER_IRQ    (TICKS_PER_IRQ%(TICKS_PER_SECOND/1000)) // (TICKS_PER_IRQ%(TICKS_PER_SECOND/1000))
  32
  33 // RTC
  34 #define PL031_BASE      0x10017000
  35 #define PL031_IRQ       10
  36 volatile struct {
  37         Uint32  DR;
  38         Uint32  MR;
  39         Uint32  LR;
  40         Uint32  CR;
  41         Uint32  IMSC;
  42         Uint32  IS;
  43         Uint32  MIS;
  44         Uint32  ICR;
  45 } *gTime_PL031;
  46 // Timer
  47 #define SP804_BASE      0x10011000
  48 #define SP805_IRQ       4
  49 volatile struct {
  50         struct {
  51                 Uint32  Load;
  52                 Uint32  Value;
  53                 Uint32  Control;
  54                 Uint32  CIS;
  55                 Uint32  RIS;
  56                 Uint32  MIS;
  57                 Uint32  BGLoad;
  58                 Uint32  _unused2;
  59         } Timers[2];
  60 } *gTime_SP804;
  61
  62 // === CODE ===
  63 void Time_int_RTCIRQHandler(int IRQ, void *unused)
  64 {
  65         if( !(gTime_PL031->IS & 1) ) {
  66                 return ;
  67         }
  68         gTime_PL031->ICR = 1;   // Clear interrupt
  69 //      giTimestamp = (Uint64)gTime_PL031->DR * 1000 - giTimeBase;
  70 }
  71
  72 void Time_int_TimerIRQHandler(int IRQ, void *unused)
  73 {
  74         if( !(gTime_SP804->Timers[0].RIS) ) {
  75                 return ;
  76         }
  77         gTime_SP804->Timers[0].CIS = 1;
  78         giTime_PartMS += PART_PER_IRQ;
  79         giTimestamp += MS_PER_IRQ;
  80         while( giTime_PartMS > TICKS_PER_MS ) {
  81                 giTime_PartMS -= TICKS_PER_MS;
  82                 giTimestamp ++;
  83         }
  84 }
  85
  86 void Time_Setup(void)
  87 {
  88         // PL031 RTC
  89         gTime_PL031 = MM_MapHWPages(PL031_BASE, 1);
  90         //IRQ_AddHandler(PL031_IRQ, Time_int_RTCIRQHandler, NULL);
  91         gTime_PL031->IMSC = 1;
  92         gTime_PL031->ICR = 1;
  93 //      giTimestamp = (Uint64)gTime_PL031->DR * 1000;
  94
  95         // SP804 Timer (Contains two basic ARM timers, each at 1MHz base)
  96         gTime_SP804 = MM_MapHWPages(SP804_BASE, 1);
  97         // - Use the first to maintain the system clock
  98         gTime_SP804->Timers[0].Load = TICKS_PER_IRQ;
  99         //  > Enable,Periodic,IE,Div=1,32bit
 100         gTime_SP804->Timers[0].Control = (1<<7)|(1<<6)|(1<<5)|(DIVISOR_ENC<<2)|(1<<1);
 101         IRQ_AddHandler(SP805_IRQ, Time_int_TimerIRQHandler, NULL);
 102         gTime_SP804->Timers[0].CIS = 1;
 103         // - TODO: use the second for short events (and use RTC for long events)
 104 }
 105
 106 tTime Time_GetTickOffset(void)
 107 {
 108         if( !gTime_SP804 )
 109                 return 0;
 110         // Want count of ms since last tick
 111         return (giTime_PartMS + gTime_SP804->Timers[0].Value) / TICKS_PER_MS;
 112 }