avr/main.c

   1 /*
   2  * (C) Copyright 2014 Leo C. <erbl259-lmu@yahoo.de>
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7
   8 #include "common.h"
   9 #include <avr/interrupt.h>
  10 #include <stdlib.h>
  11 #include <stdio.h>
  12
  13 #include "config.h"
  14 #include "debug.h"
  15 #include "z80-if.h"
  16 #include "i2c.h"
  17 #include "con-utils.h"
  18 #include "serial.h"
  19 #include "timer.h"
  20 #include "cli.h"
  21 #include "env.h"
  22 #include "z180-serv.h"
  23 #include "gpio.h"
  24 #include "time.h"
  25 #include "rtc.h"
  26
  27 static uint8_t mcusr;
  28
  29 /*--------------------------------------------------------------------------*/
  30 #if DEBUG
  31
  32 __attribute__ ((naked)) __attribute__ ((section (".init3")))
  33 void preset_ram (void)
  34 {
  35         for (uint8_t *p = RAMSTART; p <= (uint8_t *) RAMEND; p++)
  36                 *p = 0xdd;
  37
  38 }
  39
  40 static const FLASH char * const FLASH rreasons[] = {
  41                         FSTR("Power on"),
  42                         FSTR("External"),
  43                         FSTR("Brown out"),
  44                         FSTR("Watchdog"),
  45                         FSTR("JTAG"),
  46                 };
  47
  48 static
  49 void print_reset_reason(void)
  50 {
  51         uint8_t r = mcusr & 0x1f;
  52         const FLASH char * const FLASH *p = rreasons;
  53
  54         printf_P(PSTR("### Reset reason(s): %s"), r ? "" : "none");
  55         for ( ; r; p++, r >>= 1) {
  56                 if (r & 1) {
  57                         my_puts_P(*p);
  58                         if (r & ~1)
  59                                 printf_P(PSTR(", "));
  60                 }
  61         }
  62         printf_P(PSTR(".\n"));
  63 }
  64
  65 #endif
  66
  67 ISR(INT5_vect)
  68 {
  69         Stat |= S_MSG_PENDING;
  70 }
  71
  72 ISR(INT6_vect)
  73 {
  74         Stat |= S_CON_PENDING;
  75 }
  76
  77 static
  78 void setup_avr(void)
  79 {
  80         /* save and clear reset reason(s) */
  81         /* TODO: move to init section? */
  82         mcusr = MCUSR;
  83         MCUSR = 0;
  84
  85         /* WD */
  86
  87         /* CPU */
  88
  89         /* Disable JTAG Interface regardless of the JTAGEN fuse setting. */
  90         MCUCR = _BV(JTD);
  91         MCUCR = _BV(JTD);
  92
  93         /* Disable peripherals. Enable individually in respective init function. */
  94         PRR0 = _BV(PRTWI) |
  95                 _BV(PRTIM2) | _BV(PRTIM0) | _BV(PRTIM1) |
  96                 _BV(PRSPI) | _BV(PRUSART0) | _BV(PRADC);
  97
  98         PRR1 = _BV(PRTIM5) | _BV(PRTIM4) | _BV(PRTIM3) |
  99                 _BV(PRUSART3) | _BV(PRUSART2) | _BV(PRUSART1);
 100
 101
 102         /* disable analog comparator */
 103         ACSR = _BV(ACD);
 104         /* Ports */
 105
 106         /* Clock */
 107         CLKPR = _BV(CLKPCE);
 108         CLKPR = 0;
 109
 110         /* Timer */
 111         PRR1 &= ~_BV(PRTIM3);
 112         OCR3A = F_CPU / 1000 - 1;       /* Timer3: 1000Hz interval (OC3A) */
 113         TCCR3B = (0b01<<WGM32)|(0b001<<CS30); /* CTC Mode, Prescaler 1 */
 114         TIMSK3 = _BV(OCIE3A);           /* Enable TC2.oca interrupt */
 115
 116         /* INT5, INT6: falling edge */
 117         EICRB = (EICRB & ~((0b11 << ISC50) | (0b11 << ISC60))) |
 118                 (0b10 << ISC50) | (0b10 << ISC60);
 119         /* Reset pending ints */
 120         EIFR |= _BV(INTF5) | _BV(INTF6);
 121         /* Enable INT5, and INT6 */
 122         EIMSK |= _BV(INT5) | _BV(INT6);
 123 }
 124
 125 static
 126 int reset_reason_is_power_on(void)
 127 {
 128         return (mcusr & _BV(PORF)) != 0;
 129 }
 130
 131 static
 132 void setup_system_time(void)
 133 {
 134         struct tm rtc_time;
 135
 136         rtc_get(&rtc_time);
 137         rtc_time.tm_isdst = 0;
 138         set_system_time(mk_gmtime(&rtc_time) );
 139 }
 140
 141 /*--------------------------------------------------------------------------*/
 142
 143 /* Stored value of bootdelay, used by autoboot_command() */
 144 static int  stored_bootdelay;
 145
 146
 147 /***************************************************************************
 148  * Watch for 'delay' seconds for autoboot stop.
 149  * returns: 0 - no key, allow autoboot
 150  *          1 - got key, abort
 151  */
 152
 153 static int abortboot(int  bootdelay)
 154 {
 155         int abort = 0;
 156         uint32_t ts;
 157
 158         if (bootdelay >= 0)
 159                 printf_P(PSTR("Hit any key to stop autoboot: %2d "), bootdelay);
 160
 161 #if defined CONFIG_ZERO_BOOTDELAY_CHECK
 162         /*
 163          * Check if key already pressed
 164          * Don't check if bootdelay < 0
 165          */
 166         if (bootdelay >= 0) {
 167                 if (tstc()) {   /* we got a key press   */
 168                         (void) my_getchar(1);  /* consume input */
 169                         my_puts_P(PSTR("\b\b\b 0"));
 170                         abort = 1;      /* don't auto boot      */
 171                 }
 172         }
 173 #endif
 174
 175         while ((bootdelay > 0) && (!abort)) {
 176                 --bootdelay;
 177                 /* delay 1000 ms */
 178                 ts = get_timer(0);
 179                 do {
 180                         if (tstc()) {   /* we got a key press   */
 181                                 abort  = 1;     /* don't auto boot      */
 182                                 bootdelay = 0;  /* no more delay        */
 183                                 break;
 184                         }
 185                         udelay(10000);
 186                 } while (!abort && get_timer(ts) < 1000);
 187
 188                 printf_P(PSTR("\b\b\b%2d "), bootdelay);
 189         }
 190
 191         putchar('\n');
 192
 193         return abort;
 194 }
 195
 196 static
 197 const char *bootdelay_process(void)
 198 {
 199         char *s;
 200         int bootdelay;
 201
 202         bootdelay = (int) getenv_ulong(PSTR(ENV_BOOTDELAY), 10, CONFIG_BOOTDELAY);
 203
 204
 205         debug("### main_loop entered: bootdelay=%d\n\n", bootdelay);
 206         _delay_ms(20);
 207
 208         s = getenv(PSTR(ENV_BOOTCMD));
 209         stored_bootdelay = bootdelay;
 210         return s;
 211 }
 212
 213 static
 214 void autoboot_command(const char *s)
 215 {
 216         debug("### main_loop: bootcmd=\"%s\"\n", s ? s : PSTR("<UNDEFINED>"));
 217         _delay_ms(20);
 218
 219         if (stored_bootdelay != -1 && s && !abortboot(stored_bootdelay)) {
 220                 run_command_list(s, -1);
 221         }
 222 }
 223
 224
 225 static
 226 void main_loop(void)
 227 {
 228         const char *s;
 229
 230         s = bootdelay_process();
 231         autoboot_command(s);
 232         cli_loop();
 233 }
 234
 235 int main(void)
 236 {
 237         extern void setup_mmc(void);
 238
 239         for (int i = 0; i < GPIO_MAX; i++)
 240                 gpio_config(i, INPUT_PULLUP);
 241         setup_avr();
 242         setup_mmc();
 243         z80_setup_bus();
 244         env_init();
 245
 246         if (reset_reason_is_power_on())
 247                 _delay_ms(CONFIG_PWRON_DELAY);
 248
 249         serial_setup(getenv_ulong(PSTR(ENV_BAUDRATE), 10, CONFIG_BAUDRATE));
 250         sei();
 251
 252 #if DEBUG
 253         debug("\n=========================<  (RE)START DEBUG  >=========================\n");
 254         print_reset_reason();
 255 #endif
 256
 257 #if DEBUG
 258         unsigned long i_speed = getenv_ulong(PSTR("i2c_clock"), 10, CONFIG_SYS_I2C_CLOCK);
 259         debug("### Setting I2C clock Frequency to %lu Hz.\n", i_speed);
 260         i2c_init(i_speed);
 261 #else
 262         i2c_init(CONFIG_SYS_I2C_CLOCK);
 263 #endif
 264         setup_system_time();
 265
 266         printf_P(PSTR("\nATMEGA1281+Z8S180 Stamp Monitor\n\n"));
 267
 268         setup_z180_serv();
 269
 270         main_loop();
 271 }