avr/main.c

   1 /*
   2  */
   3
   4
   5 #include "common.h"
   6
   7 #include <avr/interrupt.h>
   8 #include <stdlib.h>
   9 #include <stdio.h>
  10
  11 #include "config.h"
  12 #include "debug.h"
  13 #include "z80-if.h"
  14 #include "i2c.h"
  15 #include "con-utils.h"
  16 #include "serial.h"
  17 #include "timer.h"
  18 #include "cli.h"
  19 #include "env.h"
  20 #include "z180-serv.h"
  21 #include "spi.h"
  22
  23 static uint8_t mcusr;
  24
  25 /*--------------------------------------------------------------------------*/
  26 #if DEBUG
  27
  28 __attribute__ ((naked)) __attribute__ ((section (".init3")))
  29 void preset_ram (void)
  30 {
  31         for (uint8_t *p = RAMSTART; p <= (uint8_t *) RAMEND; p++)
  32                 *p = 0xdd;
  33
  34 }
  35
  36 static const FLASH char * const FLASH rreasons[] = {
  37                         FSTR("Power on"),
  38                         FSTR("External"),
  39                         FSTR("Brown out"),
  40                         FSTR("Watchdog"),
  41                         FSTR("JTAG"),
  42                 };
  43
  44 static
  45 void print_reset_reason(void)
  46 {
  47         uint8_t r = mcusr & 0x1f;
  48         const FLASH char * const FLASH *p = rreasons;
  49
  50         printf_P(PSTR("### Reset reason(s): %s"), r ? "" : "none");
  51         for ( ; r; p++, r >>= 1) {
  52                 if (r & 1) {
  53                         my_puts_P(*p);
  54                         if (r & ~1)
  55                                 printf_P(PSTR(", "));
  56                 }
  57         }
  58         printf_P(PSTR(".\n"));
  59 }
  60
  61 #endif
  62
  63 ISR(INT5_vect)
  64 {
  65         Stat |= S_MSG_PENDING;
  66 }
  67
  68 ISR(INT6_vect)
  69 {
  70         Stat |= S_CON_PENDING;
  71 }
  72
  73 static
  74 void setup_avr(void)
  75 {
  76         /* save and clear reset reason(s) */
  77         /* TODO: move to init section? */
  78         mcusr = MCUSR;
  79         MCUSR = 0;
  80
  81         /* WD */
  82
  83         /* CPU */
  84
  85         /* Disable JTAG Interface regardless of the JTAGEN fuse setting. */
  86         MCUCR = _BV(JTD);
  87         MCUCR = _BV(JTD);
  88
  89         /* Disable peripherals. Enable individually in respective init function. */
  90         PRR0 = _BV(PRTWI) |
  91                 _BV(PRTIM2) | _BV(PRTIM0) | _BV(PRTIM1) |
  92                 _BV(PRSPI) | _BV(PRUSART0) | _BV(PRADC);
  93
  94         PRR1 = _BV(PRTIM5) | _BV(PRTIM4) | _BV(PRTIM3) |
  95                 _BV(PRUSART3) | _BV(PRUSART2) | _BV(PRUSART1);
  96
  97
  98         /* disable analog comparator */
  99         ACSR = _BV(ACD);
 100         /* Ports */
 101
 102         /* Clock */
 103         CLKPR = _BV(CLKPCE);
 104         CLKPR = 0;
 105
 106         /* Timer */
 107         PRR1 &= ~_BV(PRTIM3);
 108         OCR3A = F_CPU / 1000 - 1;       /* Timer3: 1000Hz interval (OC3A) */
 109         TCCR3B = (0b01<<WGM32)|(0b001<<CS30); /* CTC Mode, Prescaler 1 */
 110         TIMSK3 = _BV(OCIE3A);           /* Enable TC2.oca interrupt */
 111
 112         /* SPI as master */
 113         PRR0 &= ~_BV(PRSPI);
 114         SPI_DDR = (SPI_DDR & ~_BV(SPI_MISO))
 115                         | _BV(SPI_MOSI) | _BV(SPI_SCK) | _BV(SPI_SS);
 116         SPI_PORT = (SPI_PORT & ~(_BV(SPI_MOSI) | _BV(SPI_SCK)))
 117                         | _BV(SPI_SS);
 118
 119         /* INT5, INT6: falling edge */
 120         EICRB = (EICRB & ~((0b11 << ISC50) | (0b11 << ISC60))) |
 121                 (0b10 << ISC50) | (0b10 << ISC60);
 122         /* Reset pending ints */
 123         EIFR |= _BV(INTF5) | _BV(INTF6);
 124         /* Enable INT5, and INT6 */
 125         EIMSK |= _BV(INT5) | _BV(INT6);
 126 }
 127
 128 static
 129 int reset_reason_is_power_on(void)
 130 {
 131         return (mcusr & _BV(PORF)) != 0;
 132 }
 133
 134 /*--------------------------------------------------------------------------*/
 135
 136 /* Stored value of bootdelay, used by autoboot_command() */
 137 static int  stored_bootdelay;
 138
 139
 140 /***************************************************************************
 141  * Watch for 'delay' seconds for autoboot stop.
 142  * returns: 0 - no key, allow autoboot
 143  *          1 - got key, abort
 144  */
 145
 146 static int abortboot(int  bootdelay)
 147 {
 148         int abort = 0;
 149         uint32_t ts;
 150
 151         if (bootdelay >= 0)
 152                 printf_P(PSTR("Hit any key to stop autoboot: %2d "), bootdelay);
 153
 154 #if defined CONFIG_ZERO_BOOTDELAY_CHECK
 155         /*
 156          * Check if key already pressed
 157          * Don't check if bootdelay < 0
 158          */
 159         if (bootdelay >= 0) {
 160                 if (tstc()) {   /* we got a key press   */
 161                         (void) my_getchar(1);  /* consume input */
 162                         my_puts_P(PSTR("\b\b\b 0"));
 163                         abort = 1;      /* don't auto boot      */
 164                 }
 165         }
 166 #endif
 167
 168         while ((bootdelay > 0) && (!abort)) {
 169                 --bootdelay;
 170                 /* delay 1000 ms */
 171                 ts = get_timer(0);
 172                 do {
 173                         if (tstc()) {   /* we got a key press   */
 174                                 abort  = 1;     /* don't auto boot      */
 175                                 bootdelay = 0;  /* no more delay        */
 176                                 break;
 177                         }
 178                         udelay(10000);
 179                 } while (!abort && get_timer(ts) < 1000);
 180
 181                 printf_P(PSTR("\b\b\b%2d "), bootdelay);
 182         }
 183
 184         putchar('\n');
 185
 186         return abort;
 187 }
 188
 189 static
 190 const char *bootdelay_process(void)
 191 {
 192         char *s;
 193         int bootdelay;
 194
 195         bootdelay = (int) getenv_ulong(PSTR(ENV_BOOTDELAY), 10, CONFIG_BOOTDELAY);
 196
 197
 198         debug("### main_loop entered: bootdelay=%d\n\n", bootdelay);
 199         _delay_ms(20);
 200
 201         s = getenv(PSTR(ENV_BOOTCMD));
 202         stored_bootdelay = bootdelay;
 203         return s;
 204 }
 205
 206 static
 207 void autoboot_command(const char *s)
 208 {
 209         debug("### main_loop: bootcmd=\"%s\"\n", s ? s : PSTR("<UNDEFINED>"));
 210         _delay_ms(20);
 211
 212         if (stored_bootdelay != -1 && s && !abortboot(stored_bootdelay)) {
 213                 run_command_list(s, -1);
 214         }
 215 }
 216
 217
 218 static
 219 void main_loop(void)
 220 {
 221         const char *s;
 222
 223         s = bootdelay_process();
 224         autoboot_command(s);
 225         cli_loop();
 226 }
 227
 228 int main(void)
 229 {
 230         setup_avr();
 231         z80_setup_bus();
 232
 233         env_init();
 234
 235         if (reset_reason_is_power_on())
 236                 _delay_ms(CONFIG_PWRON_DELAY);
 237
 238         serial_setup(getenv_ulong(PSTR(ENV_BAUDRATE), 10, CONFIG_BAUDRATE));
 239         sei();
 240
 241 #if DEBUG
 242         debug("\n=========================<  (RE)START DEBUG  >=========================\n");
 243         print_reset_reason();
 244 #endif
 245
 246 #if DEBUG
 247         unsigned long i_speed = getenv_ulong(PSTR("i2c_clock"), 10, CONFIG_SYS_I2C_CLOCK);
 248         debug("### Setting I2C clock Frequency to %lu Hz.\n", i_speed);
 249         i2c_init(i_speed);
 250 #else
 251         i2c_init(CONFIG_SYS_I2C_CLOCK);
 252 #endif
 253
 254         printf_P(PSTR("\nATMEGA1281+Z8S180 Stamp Monitor\n\n"));
 255
 256         setup_z180_serv();
 257
 258         main_loop();
 259 }