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