git.mutantstargoat.com Git - rpikern/blob - src/rpi.c

   1 #include "rpi.h"
   2 #include "asm.h"
   3
   4 #define IOREG(offs)             (*(volatile uint32_t*)(rpi_iobase | offs))
   5
   6 /* System timer */
   7 #define STM_CTL_REG             IOREG(0x3000)
   8 #define STM_STAT_REG    STM_CTL_REG
   9 #define STM_LCNT_REG    IOREG(0x3004)
  10 #define STM_HCNT_REG    IOREG(0x3008)
  11 #define STM_CMP0_REG    IOREG(0x300c)
  12 #define STM_CMP1_REG    IOREG(0x3010)
  13 #define STM_CMP2_REG    IOREG(0x3014)
  14 #define STM_CMP3_REG    IOREG(0x3018)
  15
  16 #define STMCTL_M0               1
  17 #define STMCTL_M1               2
  18 #define STMCTL_M2               4
  19 #define STMCTL_M3               8
  20
  21 /* TIMER */
  22 #define TM_LOAD_REG             IOREG(0xb400)
  23 #define TM_VALUE_REG    IOREG(0xb404)
  24 #define TM_CTL_REG              IOREG(0xb408)
  25 #define TM_ICLR_REG             IOREG(0xb40c)
  26 #define TM_IRAW_REG             IOREG(0xb410)
  27 #define TM_IMSK_REG             IOREG(0xb414)
  28 #define TM_RELOAD_REG   IOREG(0xb418)
  29 #define TM_PREDIV_REG   IOREG(0xb41c)
  30 #define TM_COUNT_REG    IOREG(0xb420)
  31
  32 #define TMCTL_23BIT             0x000002
  33 #define TMCTL_DIV16             0x000004
  34 #define TMCTL_DIV256    0x000008
  35 #define TMCTL_DIV1              0x00000c
  36 #define TMCTL_IEN               0x000020
  37 #define TMCTL_EN                0x000080
  38 #define TMCTL_DBGHALT   0x000100
  39 #define TMCTL_CNTEN             0x000200
  40
  41 #define TMCTL_PRESCALER(x)      (((uint32_t)(x) & 0xff) << 16)
  42
  43 /* watchdog */
  44 #define PM_RSTC_REG             IOREG(0x10001c)
  45 #define PM_WDOG_REG             IOREG(0x100024)
  46
  47 #define PM_PASSWD                       0x5a000000
  48 #define PMRSTC_WRCFG_FULL_RESET 0x00000020
  49 #define PMRSTC_WRCFG_CLEAR              0xffffffcf
  50
  51 /* MAILBOX */
  52 #define MBOX_READ_REG   IOREG(0xb880)
  53 #define MBOX_POLL_REG   IOREG(0xb890)
  54 #define MBOX_SENDER_REG IOREG(0xb894)
  55 #define MBOX_STATUS_REG IOREG(0xb898)
  56 #define MBOX_CFG_REG    IOREG(0xb89c)
  57 #define MBOX_WRITE_REG  IOREG(0xb8a0)
  58
  59 /* the full bit is set when there's no space to append messages */
  60 #define MBOX_STAT_FULL  0x80000000
  61 /* the empty bit is set when there are no pending messages to be read */
  62 #define MBOX_STAT_EMPTY 0x40000000
  63
  64 static int detect(void);
  65
  66 int rpi_model;
  67 uint32_t rpi_iobase;
  68 uint32_t rpi_memsize, rpi_vc_memsize;
  69
  70 void rpi_init(void)
  71 {
  72         if((rpi_model = detect()) == -1) {
  73                 for(;;) halt_cpu();
  74         }
  75
  76         /* TODO */
  77 }
  78
  79 static int detect(void)
  80 {
  81         int i, j;
  82         uint32_t tm0, tm1;
  83         static uint32_t base[] = {0x20000000, 0x3f000000, 0xfe000000};
  84
  85         for(i=0; i<3; i++) {
  86                 rpi_iobase = base[i];
  87                 tm0 = STM_LCNT_REG;
  88                 for(j=0; j<256; j++) {
  89                         tm1 = STM_LCNT_REG;
  90                 }
  91                 if(tm0 != tm1) {
  92                         return i + 1;
  93                 }
  94         }
  95         return -1;
  96 }
  97
  98 void rpi_reboot(void)
  99 {
 100         PM_WDOG_REG = PM_PASSWD | 1;
 101         PM_RSTC_REG = PM_PASSWD | (PM_RSTC_REG & PMRSTC_WRCFG_CLEAR) | PMRSTC_WRCFG_FULL_RESET;
 102         for(;;) halt_cpu();
 103 }
 104
 105 void rpi_mbox_send(int chan, uint32_t msg)
 106 {
 107         while(MBOX_STATUS_REG & MBOX_STAT_FULL);
 108         MBOX_WRITE_REG = (msg & 0xfffffff0) | chan;
 109 }
 110
 111 uint32_t rpi_mbox_recv(int chan)
 112 {
 113         uint32_t msg;
 114         do {
 115                 while(MBOX_STATUS_REG & MBOX_STAT_EMPTY);
 116                 msg = MBOX_READ_REG;
 117         } while((msg & 0xf) != chan);
 118         return msg & 0xfffffff0;
 119 }
 120
 121 int rpi_mbox_pending(int chan)
 122 {
 123         return (MBOX_STATUS_REG & MBOX_STAT_EMPTY) == 0;
 124 }