mirror of
https://github.com/arduino/Arduino.git
synced 2024-11-30 11:24:12 +01:00
b2c43c2e55
(significant size impact: 14 bytes!)
Initialized "address" to eliminate compiler warning (4 bytes!)
Add "atmega168" as a more accurate target name than "diecimila"
(keep diecimila as well for backward compatibility)
Reduce the .hex and .lst targets that are stored in source control
to the three basics: atmega8, atmega168, atmega328. The other
targets remain in the makefile and makeall, but will need to be
built from source if wanted. Which should be less of a problem
now that the source is buildable without installing crosspack.
(cherry picked from commit 7b1ee0f1b0)
673 lines
22 KiB
C
673 lines
22 KiB
C
/**********************************************************/
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/* Optiboot bootloader for Arduino */
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/* */
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/* http://optiboot.googlecode.com */
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/* */
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/* Arduino-maintained version : See README.TXT */
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/* http://code.google.com/p/arduino/ */
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/* */
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/* Heavily optimised bootloader that is faster and */
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/* smaller than the Arduino standard bootloader */
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/* */
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/* Enhancements: */
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/* Fits in 512 bytes, saving 1.5K of code space */
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/* Background page erasing speeds up programming */
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/* Higher baud rate speeds up programming */
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/* Written almost entirely in C */
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/* Customisable timeout with accurate timeconstant */
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/* Optional virtual UART. No hardware UART required. */
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/* Optional virtual boot partition for devices without. */
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/* */
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/* What you lose: */
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/* Implements a skeleton STK500 protocol which is */
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/* missing several features including EEPROM */
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/* programming and non-page-aligned writes */
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/* High baud rate breaks compatibility with standard */
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/* Arduino flash settings */
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/* */
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/* Fully supported: */
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/* ATmega168 based devices (Diecimila etc) */
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/* ATmega328P based devices (Duemilanove etc) */
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/* */
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/* Alpha test */
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/* ATmega1280 based devices (Arduino Mega) */
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/* */
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/* Work in progress: */
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/* ATmega644P based devices (Sanguino) */
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/* ATtiny84 based devices (Luminet) */
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/* */
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/* Does not support: */
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/* USB based devices (eg. Teensy) */
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/* */
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/* Assumptions: */
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/* The code makes several assumptions that reduce the */
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/* code size. They are all true after a hardware reset, */
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/* but may not be true if the bootloader is called by */
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/* other means or on other hardware. */
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/* No interrupts can occur */
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/* UART and Timer 1 are set to their reset state */
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/* SP points to RAMEND */
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/* */
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/* Code builds on code, libraries and optimisations from: */
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/* stk500boot.c by Jason P. Kyle */
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/* Arduino bootloader http://arduino.cc */
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/* Spiff's 1K bootloader http://spiffie.org/know/arduino_1k_bootloader/bootloader.shtml */
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/* avr-libc project http://nongnu.org/avr-libc */
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/* Adaboot http://www.ladyada.net/library/arduino/bootloader.html */
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/* AVR305 Atmel Application Note */
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/* */
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/* This program is free software; you can redistribute it */
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/* and/or modify it under the terms of the GNU General */
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/* Public License as published by the Free Software */
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/* Foundation; either version 2 of the License, or */
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/* (at your option) any later version. */
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/* */
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/* This program is distributed in the hope that it will */
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/* be useful, but WITHOUT ANY WARRANTY; without even the */
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/* implied warranty of MERCHANTABILITY or FITNESS FOR A */
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/* PARTICULAR PURPOSE. See the GNU General Public */
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/* License for more details. */
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/* */
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/* You should have received a copy of the GNU General */
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/* Public License along with this program; if not, write */
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/* to the Free Software Foundation, Inc., */
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/* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
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/* */
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/* Licence can be viewed at */
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/* http://www.fsf.org/licenses/gpl.txt */
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/* */
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/**********************************************************/
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/**********************************************************/
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/* */
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/* Optional defines: */
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/* */
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/**********************************************************/
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/* */
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/* BIG_BOOT: */
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/* Build a 1k bootloader, not 512 bytes. This turns on */
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/* extra functionality. */
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/* */
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/* BAUD_RATE: */
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/* Set bootloader baud rate. */
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/* */
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/* LUDICROUS_SPEED: */
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/* 230400 baud :-) */
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/* */
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/* SOFT_UART: */
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/* Use AVR305 soft-UART instead of hardware UART. */
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/* */
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/* LED_START_FLASHES: */
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/* Number of LED flashes on bootup. */
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/* */
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/* LED_DATA_FLASH: */
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/* Flash LED when transferring data. For boards without */
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/* TX or RX LEDs, or for people who like blinky lights. */
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/* */
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/* SUPPORT_EEPROM: */
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/* Support reading and writing from EEPROM. This is not */
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/* used by Arduino, so off by default. */
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/* */
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/* TIMEOUT_MS: */
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/* Bootloader timeout period, in milliseconds. */
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/* 500,1000,2000,4000,8000 supported. */
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/* */
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/**********************************************************/
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/**********************************************************/
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/* Version Numbers! */
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/* */
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/* Arduino Optiboot now includes this Version number in */
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/* the source and object code. */
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/* */
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/* Version 3 was released as zip from the optiboot */
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/* repository and was distributed with Arduino 0022. */
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/* Version 4 starts with the arduino repository commit */
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/* that brought the arduino repository up-to-date with */
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/* the optiboot source tree changes since v3. */
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/* */
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/**********************************************************/
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/**********************************************************/
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/* Edit History: */
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/* */
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/* 4.4 WestfW: add initialization of address to keep */
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/* the compiler happy. Change SC'ed targets. */
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/* Return the SW version via READ PARAM */
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/* 4.3 WestfW: catch framing errors in getch(), so that */
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/* AVRISP works without HW kludges. */
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/* http://code.google.com/p/arduino/issues/detail?id=368n*/
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/* 4.2 WestfW: reduce code size, fix timeouts, change */
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/* verifySpace to use WDT instead of appstart */
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/* 4.1 WestfW: put version number in binary. */
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/**********************************************************/
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#define OPTIBOOT_MAJVER 4
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#define OPTIBOOT_MINVER 4
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#define MAKESTR(a) #a
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#define MAKEVER(a, b) MAKESTR(a*256+b)
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asm(" .section .version\n"
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"optiboot_version: .word " MAKEVER(OPTIBOOT_MAJVER, OPTIBOOT_MINVER) "\n"
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" .section .text\n");
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#include <inttypes.h>
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#include <avr/io.h>
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#include <avr/pgmspace.h>
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// <avr/boot.h> uses sts instructions, but this version uses out instructions
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// This saves cycles and program memory.
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#include "boot.h"
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// We don't use <avr/wdt.h> as those routines have interrupt overhead we don't need.
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#include "pin_defs.h"
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#include "stk500.h"
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#ifndef LED_START_FLASHES
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#define LED_START_FLASHES 0
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#endif
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#ifdef LUDICROUS_SPEED
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#define BAUD_RATE 230400L
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#endif
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/* set the UART baud rate defaults */
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#ifndef BAUD_RATE
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#if F_CPU >= 8000000L
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#define BAUD_RATE 115200L // Highest rate Avrdude win32 will support
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#elsif F_CPU >= 1000000L
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#define BAUD_RATE 9600L // 19200 also supported, but with significant error
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#elsif F_CPU >= 128000L
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#define BAUD_RATE 4800L // Good for 128kHz internal RC
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#else
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#define BAUD_RATE 1200L // Good even at 32768Hz
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#endif
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#endif
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/* Switch in soft UART for hard baud rates */
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#if (F_CPU/BAUD_RATE) > 280 // > 57600 for 16MHz
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#ifndef SOFT_UART
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#define SOFT_UART
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#endif
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#endif
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/* Watchdog settings */
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#define WATCHDOG_OFF (0)
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#define WATCHDOG_16MS (_BV(WDE))
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#define WATCHDOG_32MS (_BV(WDP0) | _BV(WDE))
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#define WATCHDOG_64MS (_BV(WDP1) | _BV(WDE))
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#define WATCHDOG_125MS (_BV(WDP1) | _BV(WDP0) | _BV(WDE))
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#define WATCHDOG_250MS (_BV(WDP2) | _BV(WDE))
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#define WATCHDOG_500MS (_BV(WDP2) | _BV(WDP0) | _BV(WDE))
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#define WATCHDOG_1S (_BV(WDP2) | _BV(WDP1) | _BV(WDE))
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#define WATCHDOG_2S (_BV(WDP2) | _BV(WDP1) | _BV(WDP0) | _BV(WDE))
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#ifndef __AVR_ATmega8__
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#define WATCHDOG_4S (_BV(WDP3) | _BV(WDE))
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#define WATCHDOG_8S (_BV(WDP3) | _BV(WDP0) | _BV(WDE))
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#endif
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/* Function Prototypes */
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/* The main function is in init9, which removes the interrupt vector table */
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/* we don't need. It is also 'naked', which means the compiler does not */
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/* generate any entry or exit code itself. */
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int main(void) __attribute__ ((naked)) __attribute__ ((section (".init9")));
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void putch(char);
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uint8_t getch(void);
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static inline void getNch(uint8_t); /* "static inline" is a compiler hint to reduce code size */
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void verifySpace();
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static inline void flash_led(uint8_t);
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uint8_t getLen();
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static inline void watchdogReset();
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void watchdogConfig(uint8_t x);
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#ifdef SOFT_UART
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void uartDelay() __attribute__ ((naked));
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#endif
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void appStart() __attribute__ ((naked));
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#if defined(__AVR_ATmega168__)
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#define RAMSTART (0x100)
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#define NRWWSTART (0x3800)
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#elif defined(__AVR_ATmega328P__)
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#define RAMSTART (0x100)
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#define NRWWSTART (0x7000)
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#elif defined (__AVR_ATmega644P__)
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#define RAMSTART (0x100)
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#define NRWWSTART (0xE000)
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#elif defined(__AVR_ATtiny84__)
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#define RAMSTART (0x100)
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#define NRWWSTART (0x0000)
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#elif defined(__AVR_ATmega1280__)
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#define RAMSTART (0x200)
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#define NRWWSTART (0xE000)
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#elif defined(__AVR_ATmega8__) || defined(__AVR_ATmega88__)
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#define RAMSTART (0x100)
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#define NRWWSTART (0x1800)
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#endif
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/* C zero initialises all global variables. However, that requires */
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/* These definitions are NOT zero initialised, but that doesn't matter */
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/* This allows us to drop the zero init code, saving us memory */
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#define buff ((uint8_t*)(RAMSTART))
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#ifdef VIRTUAL_BOOT_PARTITION
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#define rstVect (*(uint16_t*)(RAMSTART+SPM_PAGESIZE*2+4))
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#define wdtVect (*(uint16_t*)(RAMSTART+SPM_PAGESIZE*2+6))
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#endif
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/* main program starts here */
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int main(void) {
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uint8_t ch;
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/*
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* Making these local and in registers prevents the need for initializing
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* them, and also saves space because code no longer stores to memory.
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* (initializing address keeps the compiler happy, but isn't really
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* necessary, and uses 4 bytes of flash.)
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*/
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register uint16_t address = 0;
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register uint8_t length;
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// After the zero init loop, this is the first code to run.
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//
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// This code makes the following assumptions:
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// No interrupts will execute
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// SP points to RAMEND
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// r1 contains zero
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//
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// If not, uncomment the following instructions:
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// cli();
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asm volatile ("clr __zero_reg__");
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#ifdef __AVR_ATmega8__
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SP=RAMEND; // This is done by hardware reset
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#endif
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// Adaboot no-wait mod
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ch = MCUSR;
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MCUSR = 0;
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if (!(ch & _BV(EXTRF))) appStart();
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#if LED_START_FLASHES > 0
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// Set up Timer 1 for timeout counter
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TCCR1B = _BV(CS12) | _BV(CS10); // div 1024
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#endif
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#ifndef SOFT_UART
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#ifdef __AVR_ATmega8__
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UCSRA = _BV(U2X); //Double speed mode USART
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UCSRB = _BV(RXEN) | _BV(TXEN); // enable Rx & Tx
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UCSRC = _BV(URSEL) | _BV(UCSZ1) | _BV(UCSZ0); // config USART; 8N1
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UBRRL = (uint8_t)( (F_CPU + BAUD_RATE * 4L) / (BAUD_RATE * 8L) - 1 );
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#else
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UCSR0A = _BV(U2X0); //Double speed mode USART0
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UCSR0B = _BV(RXEN0) | _BV(TXEN0);
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UCSR0C = _BV(UCSZ00) | _BV(UCSZ01);
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UBRR0L = (uint8_t)( (F_CPU + BAUD_RATE * 4L) / (BAUD_RATE * 8L) - 1 );
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#endif
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#endif
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// Set up watchdog to trigger after 500ms
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watchdogConfig(WATCHDOG_1S);
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/* Set LED pin as output */
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LED_DDR |= _BV(LED);
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#ifdef SOFT_UART
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/* Set TX pin as output */
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UART_DDR |= _BV(UART_TX_BIT);
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#endif
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#if LED_START_FLASHES > 0
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/* Flash onboard LED to signal entering of bootloader */
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flash_led(LED_START_FLASHES * 2);
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#endif
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/* Forever loop */
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for (;;) {
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/* get character from UART */
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ch = getch();
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if(ch == STK_GET_PARAMETER) {
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unsigned char which = getch();
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verifySpace();
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if (which == 0x82) {
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/*
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* Send optiboot version as "minor SW version"
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*/
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putch(OPTIBOOT_MINVER);
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} else if (which == 0x81) {
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putch(OPTIBOOT_MAJVER);
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} else {
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/*
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* GET PARAMETER returns a generic 0x03 reply for
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* other parameters - enough to keep Avrdude happy
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*/
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putch(0x03);
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}
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}
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else if(ch == STK_SET_DEVICE) {
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// SET DEVICE is ignored
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getNch(20);
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}
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else if(ch == STK_SET_DEVICE_EXT) {
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// SET DEVICE EXT is ignored
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getNch(5);
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}
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else if(ch == STK_LOAD_ADDRESS) {
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// LOAD ADDRESS
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uint16_t newAddress;
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newAddress = getch();
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newAddress = (newAddress & 0xff) | (getch() << 8);
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#ifdef RAMPZ
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// Transfer top bit to RAMPZ
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RAMPZ = (newAddress & 0x8000) ? 1 : 0;
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#endif
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newAddress += newAddress; // Convert from word address to byte address
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address = newAddress;
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verifySpace();
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}
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else if(ch == STK_UNIVERSAL) {
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// UNIVERSAL command is ignored
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getNch(4);
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putch(0x00);
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}
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/* Write memory, length is big endian and is in bytes */
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else if(ch == STK_PROG_PAGE) {
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// PROGRAM PAGE - we support flash programming only, not EEPROM
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uint8_t *bufPtr;
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uint16_t addrPtr;
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getch(); /* getlen() */
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length = getch();
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getch();
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// If we are in RWW section, immediately start page erase
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if (address < NRWWSTART) __boot_page_erase_short((uint16_t)(void*)address);
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// While that is going on, read in page contents
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bufPtr = buff;
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do *bufPtr++ = getch();
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while (--length);
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// If we are in NRWW section, page erase has to be delayed until now.
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// Todo: Take RAMPZ into account
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if (address >= NRWWSTART) __boot_page_erase_short((uint16_t)(void*)address);
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// Read command terminator, start reply
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verifySpace();
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// If only a partial page is to be programmed, the erase might not be complete.
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// So check that here
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boot_spm_busy_wait();
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#ifdef VIRTUAL_BOOT_PARTITION
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if ((uint16_t)(void*)address == 0) {
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// This is the reset vector page. We need to live-patch the code so the
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// bootloader runs.
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//
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// Move RESET vector to WDT vector
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uint16_t vect = buff[0] | (buff[1]<<8);
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rstVect = vect;
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wdtVect = buff[8] | (buff[9]<<8);
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vect -= 4; // Instruction is a relative jump (rjmp), so recalculate.
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buff[8] = vect & 0xff;
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buff[9] = vect >> 8;
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// Add jump to bootloader at RESET vector
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buff[0] = 0x7f;
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buff[1] = 0xce; // rjmp 0x1d00 instruction
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}
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#endif
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// Copy buffer into programming buffer
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bufPtr = buff;
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addrPtr = (uint16_t)(void*)address;
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ch = SPM_PAGESIZE / 2;
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do {
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uint16_t a;
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a = *bufPtr++;
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a |= (*bufPtr++) << 8;
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__boot_page_fill_short((uint16_t)(void*)addrPtr,a);
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addrPtr += 2;
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} while (--ch);
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// Write from programming buffer
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__boot_page_write_short((uint16_t)(void*)address);
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boot_spm_busy_wait();
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#if defined(RWWSRE)
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// Reenable read access to flash
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boot_rww_enable();
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#endif
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}
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/* Read memory block mode, length is big endian. */
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else if(ch == STK_READ_PAGE) {
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// READ PAGE - we only read flash
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getch(); /* getlen() */
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length = getch();
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getch();
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verifySpace();
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#ifdef VIRTUAL_BOOT_PARTITION
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do {
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// Undo vector patch in bottom page so verify passes
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if (address == 0) ch=rstVect & 0xff;
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else if (address == 1) ch=rstVect >> 8;
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else if (address == 8) ch=wdtVect & 0xff;
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else if (address == 9) ch=wdtVect >> 8;
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else ch = pgm_read_byte_near(address);
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address++;
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putch(ch);
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} while (--length);
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#else
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#ifdef __AVR_ATmega1280__
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// do putch(pgm_read_byte_near(address++));
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// while (--length);
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do {
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uint8_t result;
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__asm__ ("elpm %0,Z\n":"=r"(result):"z"(address));
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putch(result);
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address++;
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}
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while (--length);
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#else
|
||
do putch(pgm_read_byte_near(address++));
|
||
while (--length);
|
||
#endif
|
||
#endif
|
||
}
|
||
|
||
/* Get device signature bytes */
|
||
else if(ch == STK_READ_SIGN) {
|
||
// READ SIGN - return what Avrdude wants to hear
|
||
verifySpace();
|
||
putch(SIGNATURE_0);
|
||
putch(SIGNATURE_1);
|
||
putch(SIGNATURE_2);
|
||
}
|
||
else if (ch == 'Q') {
|
||
// Adaboot no-wait mod
|
||
watchdogConfig(WATCHDOG_16MS);
|
||
verifySpace();
|
||
}
|
||
else {
|
||
// This covers the response to commands like STK_ENTER_PROGMODE
|
||
verifySpace();
|
||
}
|
||
putch(STK_OK);
|
||
}
|
||
}
|
||
|
||
void putch(char ch) {
|
||
#ifndef SOFT_UART
|
||
while (!(UCSR0A & _BV(UDRE0)));
|
||
UDR0 = ch;
|
||
#else
|
||
__asm__ __volatile__ (
|
||
" com %[ch]\n" // ones complement, carry set
|
||
" sec\n"
|
||
"1: brcc 2f\n"
|
||
" cbi %[uartPort],%[uartBit]\n"
|
||
" rjmp 3f\n"
|
||
"2: sbi %[uartPort],%[uartBit]\n"
|
||
" nop\n"
|
||
"3: rcall uartDelay\n"
|
||
" rcall uartDelay\n"
|
||
" lsr %[ch]\n"
|
||
" dec %[bitcnt]\n"
|
||
" brne 1b\n"
|
||
:
|
||
:
|
||
[bitcnt] "d" (10),
|
||
[ch] "r" (ch),
|
||
[uartPort] "I" (_SFR_IO_ADDR(UART_PORT)),
|
||
[uartBit] "I" (UART_TX_BIT)
|
||
:
|
||
"r25"
|
||
);
|
||
#endif
|
||
}
|
||
|
||
uint8_t getch(void) {
|
||
uint8_t ch;
|
||
|
||
#ifdef LED_DATA_FLASH
|
||
#ifdef __AVR_ATmega8__
|
||
LED_PORT ^= _BV(LED);
|
||
#else
|
||
LED_PIN |= _BV(LED);
|
||
#endif
|
||
#endif
|
||
|
||
#ifdef SOFT_UART
|
||
__asm__ __volatile__ (
|
||
"1: sbic %[uartPin],%[uartBit]\n" // Wait for start edge
|
||
" rjmp 1b\n"
|
||
" rcall uartDelay\n" // Get to middle of start bit
|
||
"2: rcall uartDelay\n" // Wait 1 bit period
|
||
" rcall uartDelay\n" // Wait 1 bit period
|
||
" clc\n"
|
||
" sbic %[uartPin],%[uartBit]\n"
|
||
" sec\n"
|
||
" dec %[bitCnt]\n"
|
||
" breq 3f\n"
|
||
" ror %[ch]\n"
|
||
" rjmp 2b\n"
|
||
"3:\n"
|
||
:
|
||
[ch] "=r" (ch)
|
||
:
|
||
[bitCnt] "d" (9),
|
||
[uartPin] "I" (_SFR_IO_ADDR(UART_PIN)),
|
||
[uartBit] "I" (UART_RX_BIT)
|
||
:
|
||
"r25"
|
||
);
|
||
#else
|
||
while(!(UCSR0A & _BV(RXC0)))
|
||
;
|
||
if (!(UCSR0A & _BV(FE0))) {
|
||
/*
|
||
* A Framing Error indicates (probably) that something is talking
|
||
* to us at the wrong bit rate. Assume that this is because it
|
||
* expects to be talking to the application, and DON'T reset the
|
||
* watchdog. This should cause the bootloader to abort and run
|
||
* the application "soon", if it keeps happening. (Note that we
|
||
* don't care that an invalid char is returned...)
|
||
*/
|
||
watchdogReset();
|
||
}
|
||
|
||
ch = UDR0;
|
||
#endif
|
||
|
||
#ifdef LED_DATA_FLASH
|
||
#ifdef __AVR_ATmega8__
|
||
LED_PORT ^= _BV(LED);
|
||
#else
|
||
LED_PIN |= _BV(LED);
|
||
#endif
|
||
#endif
|
||
|
||
return ch;
|
||
}
|
||
|
||
#ifdef SOFT_UART
|
||
// AVR350 equation: #define UART_B_VALUE (((F_CPU/BAUD_RATE)-23)/6)
|
||
// Adding 3 to numerator simulates nearest rounding for more accurate baud rates
|
||
#define UART_B_VALUE (((F_CPU/BAUD_RATE)-20)/6)
|
||
#if UART_B_VALUE > 255
|
||
#error Baud rate too slow for soft UART
|
||
#endif
|
||
|
||
void uartDelay() {
|
||
__asm__ __volatile__ (
|
||
"ldi r25,%[count]\n"
|
||
"1:dec r25\n"
|
||
"brne 1b\n"
|
||
"ret\n"
|
||
::[count] "M" (UART_B_VALUE)
|
||
);
|
||
}
|
||
#endif
|
||
|
||
void getNch(uint8_t count) {
|
||
do getch(); while (--count);
|
||
verifySpace();
|
||
}
|
||
|
||
void verifySpace() {
|
||
if (getch() != CRC_EOP) {
|
||
watchdogConfig(WATCHDOG_16MS); // shorten WD timeout
|
||
while (1) // and busy-loop so that WD causes
|
||
; // a reset and app start.
|
||
}
|
||
putch(STK_INSYNC);
|
||
}
|
||
|
||
#if LED_START_FLASHES > 0
|
||
void flash_led(uint8_t count) {
|
||
do {
|
||
TCNT1 = -(F_CPU/(1024*16));
|
||
TIFR1 = _BV(TOV1);
|
||
while(!(TIFR1 & _BV(TOV1)));
|
||
#ifdef __AVR_ATmega8__
|
||
LED_PORT ^= _BV(LED);
|
||
#else
|
||
LED_PIN |= _BV(LED);
|
||
#endif
|
||
watchdogReset();
|
||
} while (--count);
|
||
}
|
||
#endif
|
||
|
||
// Watchdog functions. These are only safe with interrupts turned off.
|
||
void watchdogReset() {
|
||
__asm__ __volatile__ (
|
||
"wdr\n"
|
||
);
|
||
}
|
||
|
||
void watchdogConfig(uint8_t x) {
|
||
WDTCSR = _BV(WDCE) | _BV(WDE);
|
||
WDTCSR = x;
|
||
}
|
||
|
||
void appStart() {
|
||
watchdogConfig(WATCHDOG_OFF);
|
||
__asm__ __volatile__ (
|
||
#ifdef VIRTUAL_BOOT_PARTITION
|
||
// Jump to WDT vector
|
||
"ldi r30,4\n"
|
||
"clr r31\n"
|
||
#else
|
||
// Jump to RST vector
|
||
"clr r30\n"
|
||
"clr r31\n"
|
||
#endif
|
||
"ijmp\n"
|
||
);
|
||
}
|