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 #include "gpio.h"
  23
  24 static uint8_t mcusr;
  25
  26 /*--------------------------------------------------------------------------*/
  27 #if DEBUG
  28
  29 __attribute__ ((naked)) __attribute__ ((section (".init3")))
  30 void preset_ram (void)
  31 {
  32         for (uint8_t *p = RAMSTART; p <= (uint8_t *) RAMEND; p++)
  33                 *p = 0xdd;
  34
  35 }
  36
  37 static const FLASH char * const FLASH rreasons[] = {
  38                         FSTR("Power on"),
  39                         FSTR("External"),
  40                         FSTR("Brown out"),
  41                         FSTR("Watchdog"),
  42                         FSTR("JTAG"),
  43                 };
  44
  45 static
  46 void print_reset_reason(void)
  47 {
  48         uint8_t r = mcusr & 0x1f;
  49         const FLASH char * const FLASH *p = rreasons;
  50
  51         printf_P(PSTR("### Reset reason(s): %s"), r ? "" : "none");
  52         for ( ; r; p++, r >>= 1) {
  53                 if (r & 1) {
  54                         my_puts_P(*p);
  55                         if (r & ~1)
  56                                 printf_P(PSTR(", "));
  57                 }
  58         }
  59         printf_P(PSTR(".\n"));
  60 }
  61
  62 #endif
  63
  64 ISR(INT5_vect)
  65 {
  66         Stat |= S_MSG_PENDING;
  67 }
  68
  69 ISR(INT6_vect)
  70 {
  71         Stat |= S_CON_PENDING;
  72 }
  73
  74 static
  75 void setup_avr(void)
  76 {
  77         /* save and clear reset reason(s) */
  78         /* TODO: move to init section? */
  79         mcusr = MCUSR;
  80         MCUSR = 0;
  81
  82         /* WD */
  83
  84         /* CPU */
  85
  86         /* Disable JTAG Interface regardless of the JTAGEN fuse setting. */
  87         MCUCR = _BV(JTD);
  88         MCUCR = _BV(JTD);
  89
  90         /* Disable peripherals. Enable individually in respective init function. */
  91         PRR0 = _BV(PRTWI) |
  92                 _BV(PRTIM2) | _BV(PRTIM0) | _BV(PRTIM1) |
  93                 _BV(PRSPI) | _BV(PRUSART0) | _BV(PRADC);
  94
  95         PRR1 = _BV(PRTIM5) | _BV(PRTIM4) | _BV(PRTIM3) |
  96                 _BV(PRUSART3) | _BV(PRUSART2) | _BV(PRUSART1);
  97
  98
  99         /* disable analog comparator */
 100         ACSR = _BV(ACD);
 101         /* Ports */
 102
 103         /* Clock */
 104         CLKPR = _BV(CLKPCE);
 105         CLKPR = 0;
 106
 107         /* Timer */
 108         PRR1 &= ~_BV(PRTIM3);
 109         OCR3A = F_CPU / 1000 - 1;       /* Timer3: 1000Hz interval (OC3A) */
 110         TCCR3B = (0b01<<WGM32)|(0b001<<CS30); /* CTC Mode, Prescaler 1 */
 111         TIMSK3 = _BV(OCIE3A);           /* Enable TC2.oca interrupt */
 112
 113         /* SPI as master */
 114         PRR0 &= ~_BV(PRSPI);
 115         SPI_DDR = (SPI_DDR & ~_BV(SPI_MISO))
 116                         | _BV(SPI_MOSI) | _BV(SPI_SCK) | _BV(SPI_SS);
 117         SPI_PORT = (SPI_PORT & ~(_BV(SPI_MOSI) | _BV(SPI_SCK)))
 118                         | _BV(SPI_SS);
 119
 120         /* INT5, INT6: falling edge */
 121         EICRB = (EICRB & ~((0b11 << ISC50) | (0b11 << ISC60))) |
 122                 (0b10 << ISC50) | (0b10 << ISC60);
 123         /* Reset pending ints */
 124         EIFR |= _BV(INTF5) | _BV(INTF6);
 125         /* Enable INT5, and INT6 */
 126         EIMSK |= _BV(INT5) | _BV(INT6);
 127 }
 128
 129 static
 130 int reset_reason_is_power_on(void)
 131 {
 132         return (mcusr & _BV(PORF)) != 0;
 133 }
 134
 135 /*--------------------------------------------------------------------------*/
 136
 137 /* Stored value of bootdelay, used by autoboot_command() */
 138 static int  stored_bootdelay;
 139
 140
 141 /***************************************************************************
 142  * Watch for 'delay' seconds for autoboot stop.
 143  * returns: 0 - no key, allow autoboot
 144  *          1 - got key, abort
 145  */
 146
 147 static int abortboot(int  bootdelay)
 148 {
 149         int abort = 0;
 150         uint32_t ts;
 151
 152         if (bootdelay >= 0)
 153                 printf_P(PSTR("Hit any key to stop autoboot: %2d "), bootdelay);
 154
 155 #if defined CONFIG_ZERO_BOOTDELAY_CHECK
 156         /*
 157          * Check if key already pressed
 158          * Don't check if bootdelay < 0
 159          */
 160         if (bootdelay >= 0) {
 161                 if (tstc()) {   /* we got a key press   */
 162                         (void) my_getchar(1);  /* consume input */
 163                         my_puts_P(PSTR("\b\b\b 0"));
 164                         abort = 1;      /* don't auto boot      */
 165                 }
 166         }
 167 #endif
 168
 169         while ((bootdelay > 0) && (!abort)) {
 170                 --bootdelay;
 171                 /* delay 1000 ms */
 172                 ts = get_timer(0);
 173                 do {
 174                         if (tstc()) {   /* we got a key press   */
 175                                 abort  = 1;     /* don't auto boot      */
 176                                 bootdelay = 0;  /* no more delay        */
 177                                 break;
 178                         }
 179                         udelay(10000);
 180                 } while (!abort && get_timer(ts) < 1000);
 181
 182                 printf_P(PSTR("\b\b\b%2d "), bootdelay);
 183         }
 184
 185         putchar('\n');
 186
 187         return abort;
 188 }
 189
 190 static
 191 const char *bootdelay_process(void)
 192 {
 193         char *s;
 194         int bootdelay;
 195
 196         bootdelay = (int) getenv_ulong(PSTR(ENV_BOOTDELAY), 10, CONFIG_BOOTDELAY);
 197
 198
 199         debug("### main_loop entered: bootdelay=%d\n\n", bootdelay);
 200         _delay_ms(20);
 201
 202         s = getenv(PSTR(ENV_BOOTCMD));
 203         stored_bootdelay = bootdelay;
 204         return s;
 205 }
 206
 207 static
 208 void autoboot_command(const char *s)
 209 {
 210         debug("### main_loop: bootcmd=\"%s\"\n", s ? s : PSTR("<UNDEFINED>"));
 211         _delay_ms(20);
 212
 213         if (stored_bootdelay != -1 && s && !abortboot(stored_bootdelay)) {
 214                 run_command_list(s, -1);
 215         }
 216 }
 217
 218
 219 static
 220 void main_loop(void)
 221 {
 222         const char *s;
 223
 224         s = bootdelay_process();
 225         autoboot_command(s);
 226         cli_loop();
 227 }
 228
 229 int main(void)
 230 {
 231         setup_avr();
 232         z80_setup_bus();
 233         for (int i = 0; i < GPIO_MAX; i++)
 234                 gpio_config(i, INPUT_PULLUP);
 235         env_init();
 236
 237         if (reset_reason_is_power_on())
 238                 _delay_ms(CONFIG_PWRON_DELAY);
 239
 240         serial_setup(getenv_ulong(PSTR(ENV_BAUDRATE), 10, CONFIG_BAUDRATE));
 241         sei();
 242
 243 #if DEBUG
 244         debug("\n=========================<  (RE)START DEBUG  >=========================\n");
 245         print_reset_reason();
 246 #endif
 247
 248 #if DEBUG
 249         unsigned long i_speed = getenv_ulong(PSTR("i2c_clock"), 10, CONFIG_SYS_I2C_CLOCK);
 250         debug("### Setting I2C clock Frequency to %lu Hz.\n", i_speed);
 251         i2c_init(i_speed);
 252 #else
 253         i2c_init(CONFIG_SYS_I2C_CLOCK);
 254 #endif
 255
 256         printf_P(PSTR("\nATMEGA1281+Z8S180 Stamp Monitor\n\n"));
 257
 258         setup_z180_serv();
 259
 260         main_loop();
 261 }