#include <stdint.h>
#include <stdbool.h>
#include <avr/io.h>
#include <avr/eeprom.h>
#include <avr/interrupt.h>
#include <avr/wdt.h>
#include <util/delay.h>
#include "bootloader.h"
#include <avr/boot.h>
#ifdef PROTOCOL_LUFA
#include <LUFA/Drivers/USB/USB.h>
#endif
/** \brief Bootloader Size in *bytes*
*
* AVR Boot section size are defined by setting BOOTSZ fuse in fact. Consult with your MCU datasheet.
* Note that 'Word'(2 bytes) size and address are used in datasheet while TMK uses 'Byte'.
*
* Size of Bootloaders in bytes:
* Atmel DFU loader(ATmega32U4) 4096
* Atmel DFU loader(AT90USB128) 8192
* LUFA bootloader(ATmega32U4) 4096
* Arduino Caterina(ATmega32U4) 4096
* USBaspLoader(ATmega***) 2048
* Teensy halfKay(ATmega32U4) 512
* Teensy++ halfKay(AT90USB128) 1024
*
* AVR Boot section is located at the end of Flash memory like the followings.
*
* byte Atmel/LUFA(ATMega32u4) byte Atmel(AT90SUB128)
* 0x0000 +---------------+ 0x00000 +---------------+
* | | | |
* | | | |
* | Application | | Application |
* | | | |
* = = = =
* | | 32KB-4KB | | 128KB-8KB
* 0x7000 +---------------+ 0x1E000 +---------------+
* | Bootloader | 4KB | Bootloader | 8KB
* 0x7FFF +---------------+ 0x1FFFF +---------------+
*
*
* byte Teensy(ATMega32u4) byte Teensy++(AT90SUB128)
* 0x0000 +---------------+ 0x00000 +---------------+
* | | | |
* | | | |
* | Application | | Application |
* | | | |
* = = = =
* | | 32KB-512B | | 128KB-1KB
* 0x7E00 +---------------+ 0x1FC00 +---------------+
* | Bootloader | 512B | Bootloader | 1KB
* 0x7FFF +---------------+ 0x1FFFF +---------------+
*/
#define FLASH_SIZE (FLASHEND + 1L)
#if !defined(BOOTLOADER_SIZE)
uint16_t bootloader_start;
#endif
#define BOOT_SIZE_256 0b110
#define BOOT_SIZE_512 0b100
#define BOOT_SIZE_1024 0b010
#define BOOT_SIZE_2048 0b000
/** \brief Entering the Bootloader via Software
*
* http://www.fourwalledcubicle.com/files/LUFA/Doc/120730/html/_page__software_bootloader_start.html
*/
#define BOOTLOADER_RESET_KEY 0xB007B007
uint32_t reset_key __attribute__ ((section (".noinit,\"aw\",@nobits;")));
/** \brief initialize MCU status by watchdog reset
*
* FIXME: needs doc
*/
void bootloader_jump(void) {
#if !defined(BOOTLOADER_SIZE)
uint8_t high_fuse = boot_lock_fuse_bits_get(GET_HIGH_FUSE_BITS);
if (high_fuse & BOOT_SIZE_256) {
bootloader_start = (FLASH_SIZE - 512) >> 1;
} else if (high_fuse & BOOT_SIZE_512) {
bootloader_start = (FLASH_SIZE - 1024) >> 1;
} else if (high_fuse & BOOT_SIZE_1024) {
bootloader_start = (FLASH_SIZE - 2048) >> 1;
} else {
bootloader_start = (FLASH_SIZE - 4096) >> 1;
}
#endif
// Something like this might work, but it compiled larger than the block above
// bootloader_start = FLASH_SIZE - (256 << (~high_fuse & 0b110 >> 1));
#if defined(BOOTLOADER_HALFKAY)
// http://www.pjrc.com/teensy/jump_to_bootloader.html
cli();
// disable watchdog, if enabled (it's not)
// disable all peripherals
// a shutdown call might make sense here
UDCON = 1;
USBCON = (1<<FRZCLK); // disable USB
UCSR1B = 0;
_delay_ms(5);
#if defined(__AVR_AT90USB162__) // Teensy 1.0
EIMSK = 0; PCICR = 0; SPCR = 0; ACSR = 0; EECR = 0;
TIMSK0 = 0; TIMSK1 = 0; UCSR1B = 0;
DDRB = 0; DDRC = 0; DDRD = 0;
PORTB = 0; PORTC = 0; PORTD = 0;
asm volatile("jmp 0x3E00");
#elif defined(__AVR_ATmega32U4__) // Teensy 2.0
EIMSK = 0; PCICR = 0; SPCR = 0; ACSR = 0; EECR = 0; ADCSRA = 0;
TIMSK0 = 0; TIMSK1 = 0; TIMSK3 = 0; TIMSK4 = 0; UCSR1B = 0; TWCR = 0;
DDRB = 0; DDRC = 0; DDRD = 0; DDRE = 0; DDRF = 0; TWCR = 0;
PORTB = 0; PORTC = 0; PORTD = 0; PORTE = 0; PORTF = 0;
asm volatile("jmp 0x7E00");
#elif defined(__AVR_AT90USB646__) // Teensy++ 1.0
EIMSK = 0; PCICR = 0; SPCR = 0; ACSR = 0; EECR = 0; ADCSRA = 0;
TIMSK0 = 0; TIMSK1 = 0; TIMSK2 = 0; TIMSK3 = 0; UCSR1B = 0; TWCR = 0;
DDRA = 0; DDRB = 0; DDRC = 0; DDRD = 0; DDRE = 0; DDRF = 0;
PORTA = 0; PORTB = 0; PORTC = 0; PORTD = 0; PORTE = 0; PORTF = 0;
asm volatile("jmp 0xFC00");
#elif defined(__AVR_AT90USB1286__) // Teensy++ 2.0
EIMSK = 0; PCICR = 0; SPCR = 0; ACSR = 0; EECR = 0; ADCSRA = 0;
TIMSK0 = 0; TIMSK1 = 0; TIMSK2 = 0; TIMSK3 = 0; UCSR1B = 0; TWCR = 0;
DDRA = 0; DDRB = 0; DDRC = 0; DDRD = 0; DDRE = 0; DDRF = 0;
PORTA = 0; PORTB = 0; PORTC = 0; PORTD = 0; PORTE = 0; PORTF = 0;
asm volatile("jmp 0x1FC00");
#endif
#elif defined(BOOTLOADER_CATERINA)
// this block may be optional
// TODO: figure it out
uint16_t *const bootKeyPtr = (uint16_t *)0x0800;
// Value used by Caterina bootloader use to determine whether to run the
// sketch or the bootloader programmer.
uint16_t bootKey = 0x7777;
*bootKeyPtr = bootKey;
// setup watchdog timeout
wdt_enable(WDTO_60MS);
while(1) {} // wait for watchdog timer to trigger
#else // Assume remaining boards are DFU, even if the flag isn't set
#if !(defined(__AVR_ATmega32A__) || defined(__AVR_ATmega328P__)) // no USB - maybe BOOTLOADER_BOOTLOADHID instead though?
UDCON = 1;
USBCON = (1<<FRZCLK); // disable USB
UCSR1B = 0;
_delay_ms(5); // 5 seems to work fine
#endif
#ifdef BOOTLOADER_BOOTLOADHID
// force bootloadHID to stay in bootloader mode, so that it waits
// for a new firmware to be flashed
eeprom_write_byte((uint8_t *)1, 0x00);
#endif
// watchdog reset
reset_key = BOOTLOADER_RESET_KEY;
wdt_enable(WDTO_250MS);
for (;;);
#endif
}
#ifdef __AVR_ATmega32A__
// MCUSR is actually called MCUCSR in ATmega32A
#define MCUSR MCUCSR
#endif
/* this runs before main() */
void bootloader_jump_after_watchdog_reset(void) __attribute__ ((used, naked, section (".init3")));
void bootloader_jump_after_watchdog_reset(void)
{
#ifndef BOOTLOADER_HALFKAY
if ((MCUSR & (1<<WDRF)) && reset_key == BOOTLOADER_RESET_KEY) {
reset_key = 0;
// My custom USBasploader requires this to come up.
MCUSR = 0;
// Seems like Teensy halfkay loader requires clearing WDRF and disabling watchdog.
MCUSR &= ~(1<<WDRF);
wdt_disable();
// This is compled into 'icall', address should be in word unit, not byte.
#ifdef BOOTLOADER_SIZE
((void (*)(void))( (FLASH_SIZE - BOOTLOADER_SIZE) >> 1))();
#else
asm("ijmp" :: "z" (bootloader_start));
#endif
}
#endif
}
#if 0
/*
* USBaspLoader - I'm not sure if this is used at all in any projects
* would love to support it if it is -Jack
*/
#if defined(__AVR_ATmega168__) || defined(__AVR_ATmega168P__) || defined(__AVR_ATmega328P__)
// This makes custom USBasploader come up.
MCUSR = 0;
// initialize ports
PORTB = 0; PORTC= 0; PORTD = 0;
DDRB = 0; DDRC= 0; DDRD = 0;
// disable interrupts
EIMSK = 0; EECR = 0; SPCR = 0;
ACSR = 0; SPMCSR = 0; WDTCSR = 0; PCICR = 0;
TIMSK0 = 0; TIMSK1 = 0; TIMSK2 = 0;
ADCSRA = 0; TWCR = 0; UCSR0B = 0;
#endif
// This is compled into 'icall', address should be in word unit, not byte.
((void (*)(void))(BOOTLOADER_START/2))();
}
#endif