avr/main.c

   1 /*
   2  */
   3
   4
   5 #include "common.h"
   6
   7 #include <util/delay.h>
   8 #include <avr/interrupt.h>
   9 #include <stdlib.h>
  10 #include <stdio.h>
  11
  12 #include "config.h"
  13 #include "debug.h"
  14 #include "z80-if.h"
  15 #include "i2c.h"
  16 #include "con-utils.h"
  17 #include "serial.h"
  18 #include "timer.h"
  19 #include "cli.h"
  20 #include "env.h"
  21 #include "z180-serv.h"
  22
  23 #define udelay(n)  _delay_us(n)
  24
  25 static uint8_t mcusr;
  26
  27 /*--------------------------------------------------------------------------*/
  28 #if DEBUG
  29
  30 __attribute__ ((naked)) __attribute__ ((section (".init3")))
  31 void preset_ram (void)
  32 {
  33         for (uint8_t *p = RAMSTART; p <= (uint8_t *) RAMEND; p++)
  34                 *p = 0xdd;
  35
  36 }
  37
  38 static const FLASH char * const FLASH rreasons[] = {
  39                         FSTR("Power on"),
  40                         FSTR("External"),
  41                         FSTR("Brown out"),
  42                         FSTR("Watchdog"),
  43                         FSTR("JTAG"),
  44                 };
  45
  46 static
  47 void print_reset_reason(void)
  48 {
  49         uint8_t r = mcusr & 0x1f;
  50         const FLASH char * const FLASH *p = rreasons;
  51
  52         printf_P(PSTR("### Reset reason(s): %s"), r ? "" : "none");
  53         for ( ; r; p++, r >>= 1) {
  54                 if (r & 1) {
  55                         my_puts_P(*p);
  56                         if (r & ~1)
  57                                 printf_P(PSTR(", "));
  58                 }
  59         }
  60         printf_P(PSTR(".\n"));
  61 }
  62
  63 #endif
  64
  65 ISR(INT5_vect)
  66 {
  67         Stat |= S_MSG_PENDING;
  68 }
  69
  70 ISR(INT6_vect)
  71 {
  72         Stat |= S_CON_PENDING;
  73 }
  74
  75 static
  76 void setup_avr(void)
  77 {
  78         /* save and clear reset reason(s) */
  79         /* TODO: move to init section? */
  80         mcusr = MCUSR;
  81         MCUSR = 0;
  82
  83         /* WD */
  84
  85         /* CPU */
  86
  87         /* Disable JTAG Interface regardless of the JTAGEN fuse setting. */
  88         MCUCR = _BV(JTD);
  89         MCUCR = _BV(JTD);
  90
  91         /* Disable peripherals. Enable individually in respective init function. */
  92         PRR0 = _BV(PRTWI) |
  93                 _BV(PRTIM2) | _BV(PRTIM0) | _BV(PRTIM1) |
  94                 _BV(PRSPI) | _BV(PRUSART0) | _BV(PRADC);
  95
  96         PRR1 = _BV(PRTIM5) | _BV(PRTIM4) | _BV(PRTIM3) |
  97                 _BV(PRUSART3) | _BV(PRUSART2) | _BV(PRUSART1);
  98
  99
 100         /* disable analog comparator */
 101         ACSR = _BV(ACD);
 102         /* Ports */
 103
 104         /* Clock */
 105         CLKPR = _BV(CLKPCE);
 106         CLKPR = 0;
 107
 108         /* Timer */
 109         PRR1 &= ~_BV(PRTIM3);
 110         OCR3A = F_CPU / 1000 - 1;       /* Timer3: 1000Hz interval (OC3A) */
 111         TCCR3B = (0b01<<WGM32)|(0b001<<CS30); /* CTC Mode, Prescaler 1 */
 112         TIMSK3 = _BV(OCIE3A);           /* Enable TC2.oca interrupt */
 113
 114         /* INT5, INT6: falling edge */
 115         EICRB = (EICRB & ~((0b11 << ISC50) | (0b11 << ISC60))) |
 116                 (0b10 << ISC50) | (0b10 << ISC60);
 117         /* Reset pending ints */
 118         EIFR |= _BV(INTF5) | _BV(INTF6);
 119         /* Enable INT5, and INT6 */
 120         EIMSK |= _BV(INT5) | _BV(INT6);
 121 }
 122
 123 static
 124 int reset_reason_is_power_on(void)
 125 {
 126         return (mcusr & _BV(PORF)) != 0;
 127 }
 128
 129 /*--------------------------------------------------------------------------*/
 130
 131 /* Stored value of bootdelay, used by autoboot_command() */
 132 static int  stored_bootdelay;
 133
 134
 135 /***************************************************************************
 136  * Watch for 'delay' seconds for autoboot stop.
 137  * returns: 0 - no key, allow autoboot
 138  *          1 - got key, abort
 139  */
 140
 141 static int abortboot(int  bootdelay)
 142 {
 143         int abort = 0;
 144         uint32_t ts;
 145
 146         if (bootdelay >= 0)
 147                 printf_P(PSTR("Hit any key to stop autoboot: %2d "), bootdelay);
 148
 149 #if defined CONFIG_ZERO_BOOTDELAY_CHECK
 150         /*
 151          * Check if key already pressed
 152          * Don't check if bootdelay < 0
 153          */
 154         if (bootdelay >= 0) {
 155                 if (tstc()) {   /* we got a key press   */
 156                         (void) my_getchar(1);  /* consume input */
 157                         my_puts_P(PSTR("\b\b\b 0"));
 158                         abort = 1;      /* don't auto boot      */
 159                 }
 160         }
 161 #endif
 162
 163         while ((bootdelay > 0) && (!abort)) {
 164                 --bootdelay;
 165                 /* delay 1000 ms */
 166                 ts = get_timer(0);
 167                 do {
 168                         if (tstc()) {   /* we got a key press   */
 169                                 abort  = 1;     /* don't auto boot      */
 170                                 bootdelay = 0;  /* no more delay        */
 171                                 break;
 172                         }
 173                         udelay(10000);
 174                 } while (!abort && get_timer(ts) < 1000);
 175
 176                 printf_P(PSTR("\b\b\b%2d "), bootdelay);
 177         }
 178
 179         putchar('\n');
 180
 181         return abort;
 182 }
 183
 184 static
 185 const char *bootdelay_process(void)
 186 {
 187         char *s;
 188         int bootdelay;
 189
 190         bootdelay = (int) getenv_ulong(PSTR(ENV_BOOTDELAY), 10, CONFIG_BOOTDELAY);
 191
 192
 193         debug("### main_loop entered: bootdelay=%d\n\n", bootdelay);
 194         _delay_ms(20);
 195
 196         s = getenv(PSTR(ENV_BOOTCMD));
 197         stored_bootdelay = bootdelay;
 198         return s;
 199 }
 200
 201 static
 202 void autoboot_command(const char *s)
 203 {
 204         debug("### main_loop: bootcmd=\"%s\"\n", s ? s : PSTR("<UNDEFINED>"));
 205         _delay_ms(20);
 206
 207         if (stored_bootdelay != -1 && s && !abortboot(stored_bootdelay)) {
 208                 run_command_list(s, -1);
 209         }
 210 }
 211
 212
 213 static
 214 void main_loop(void)
 215 {
 216         const char *s;
 217
 218         s = bootdelay_process();
 219         autoboot_command(s);
 220         cli_loop();
 221 }
 222
 223 int main(void)
 224 {
 225
 226         setup_avr();
 227         z80_setup_bus();
 228
 229         env_init();
 230
 231         if (reset_reason_is_power_on())
 232                 _delay_ms(CONFIG_PWRON_DELAY);
 233
 234         serial_setup(getenv_ulong(PSTR(ENV_BAUDRATE), 10, CONFIG_BAUDRATE));
 235         sei();
 236
 237 #if DEBUG
 238         debug("\n=========================<  (RE)START DEBUG  >=========================\n");
 239         print_reset_reason();
 240 #endif
 241
 242 #if DEBUG
 243         unsigned long i_speed = getenv_ulong(PSTR("i2c_clock"), 10, CONFIG_SYS_I2C_CLOCK);
 244         debug("### Setting I2C clock Frequency to %lu Hz.\n", i_speed);
 245         i2c_init(i_speed);
 246 #else
 247         i2c_init(CONFIG_SYS_I2C_CLOCK);
 248 #endif
 249
 250         printf_P(PSTR("\nATMEGA1281+Z8S180 Stamp Monitor\n\n"));
 251
 252         setup_z180_serv();
 253
 254         main_loop();
 255 }