Bootloaders/HID/BootloaderHID.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2012.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2012  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *
  33  *  Main source file for the HID class bootloader. This file contains the complete bootloader logic.
  34  */
  35
  36 #include "BootloaderHID.h"
  37
  38 /** Flag to indicate if the bootloader should be running, or should exit and allow the application code to run
  39  *  via a soft reset. When cleared, the bootloader will abort, the USB interface will shut down and the application
  40  *  started via a forced watchdog reset.
  41  */
  42 static bool RunBootloader = true;
  43
  44 /** Magic lock for forced application start. If the HWBE fuse is programmed and BOOTRST is unprogrammed, the bootloader
  45  *  will start if the /HWB line of the AVR is held low and the system is reset. However, if the /HWB line is still held
  46  *  low when the application attempts to start via a watchdog reset, the bootloader will re-start. If set to the value
  47  *  \ref MAGIC_BOOT_KEY the special init function \ref Application_Jump_Check() will force the application to start.
  48  */
  49 uint32_t MagicBootKey ATTR_NO_INIT;
  50
  51
  52 /** Special startup routine to check if the bootloader was started via a watchdog reset, and if the magic application
  53  *  start key has been loaded into \ref MagicBootKey. If the bootloader started via the watchdog and the key is valid,
  54  *  this will force the user application to start via a software jump.
  55  */
  56 void Application_Jump_Check(void)
  57 {
  58         /* If the reset source was the bootloader and the key is correct, clear it and jump to the application */
  59         if ((MCUSR & (1 << WDRF)) && (MagicBootKey == MAGIC_BOOT_KEY))
  60         {
  61                 MagicBootKey = 0;
  62                 // cppcheck-suppress constStatement
  63                 ((void (*)(void))0x0000)();
  64         }
  65 }
  66
  67 /** Main program entry point. This routine configures the hardware required by the bootloader, then continuously
  68  *  runs the bootloader processing routine until instructed to soft-exit.
  69  */
  70 int main(void)
  71 {
  72         /* Setup hardware required for the bootloader */
  73         SetupHardware();
  74
  75         /* Enable global interrupts so that the USB stack can function */
  76         sei();
  77
  78         while (RunBootloader)
  79           USB_USBTask();
  80
  81         /* Disconnect from the host - USB interface will be reset later along with the AVR */
  82         USB_Detach();
  83
  84         /* Unlock the forced application start mode of the bootloader if it is restarted */
  85         MagicBootKey = MAGIC_BOOT_KEY;
  86
  87         /* Enable the watchdog and force a timeout to reset the AVR */
  88         wdt_enable(WDTO_250MS);
  89
  90         for (;;);
  91 }
  92
  93 /** Configures all hardware required for the bootloader. */
  94 static void SetupHardware(void)
  95 {
  96         /* Disable watchdog if enabled by bootloader/fuses */
  97         MCUSR &= ~(1 << WDRF);
  98         wdt_disable();
  99
 100         /* Relocate the interrupt vector table to the bootloader section */
 101         MCUCR = (1 << IVCE);
 102         MCUCR = (1 << IVSEL);
 103
 104         /* Initialize USB subsystem */
 105         USB_Init();
 106 }
 107
 108 /** Event handler for the USB_ConfigurationChanged event. This configures the device's endpoints ready
 109  *  to relay data to and from the attached USB host.
 110  */
 111 void EVENT_USB_Device_ConfigurationChanged(void)
 112 {
 113         /* Setup HID Report Endpoint */
 114         Endpoint_ConfigureEndpoint(HID_IN_EPADDR, EP_TYPE_INTERRUPT, HID_IN_EPSIZE, 1);
 115 }
 116
 117 /** Event handler for the USB_ControlRequest event. This is used to catch and process control requests sent to
 118  *  the device from the USB host before passing along unhandled control requests to the library for processing
 119  *  internally.
 120  */
 121 void EVENT_USB_Device_ControlRequest(void)
 122 {
 123         /* Ignore any requests that aren't directed to the HID interface */
 124         if ((USB_ControlRequest.bmRequestType & (CONTROL_REQTYPE_TYPE | CONTROL_REQTYPE_RECIPIENT)) !=
 125             (REQTYPE_CLASS | REQREC_INTERFACE))
 126         {
 127                 return;
 128         }
 129
 130         /* Process HID specific control requests */
 131         switch (USB_ControlRequest.bRequest)
 132         {
 133                 case HID_REQ_SetReport:
 134                         Endpoint_ClearSETUP();
 135
 136                         /* Wait until the command has been sent by the host */
 137                         while (!(Endpoint_IsOUTReceived()));
 138
 139                         /* Read in the write destination address */
 140                         #if (FLASHEND > 0xFFFF)
 141                         uint32_t PageAddress = ((uint32_t)Endpoint_Read_16_LE() << 8);
 142                         #else
 143                         uint16_t PageAddress = Endpoint_Read_16_LE();
 144                         #endif
 145
 146                         /* Check if the command is a program page command, or a start application command */
 147                         #if (FLASHEND > 0xFFFF)
 148                         if ((uint16_t)(PageAddress >> 8) == COMMAND_STARTAPPLICATION)
 149                         #else
 150                         if (PageAddress == COMMAND_STARTAPPLICATION)
 151                         #endif
 152                         {
 153                                 RunBootloader = false;
 154                         }
 155                         else
 156                         {
 157                                 /* Erase the given FLASH page, ready to be programmed */
 158                                 boot_page_erase(PageAddress);
 159                                 boot_spm_busy_wait();
 160
 161                                 /* Write each of the FLASH page's bytes in sequence */
 162                                 for (uint8_t PageWord = 0; PageWord < (SPM_PAGESIZE / 2); PageWord++)
 163                                 {
 164                                         /* Check if endpoint is empty - if so clear it and wait until ready for next packet */
 165                                         if (!(Endpoint_BytesInEndpoint()))
 166                                         {
 167                                                 Endpoint_ClearOUT();
 168                                                 while (!(Endpoint_IsOUTReceived()));
 169                                         }
 170
 171                                         /* Write the next data word to the FLASH page */
 172                                         boot_page_fill(PageAddress + ((uint16_t)PageWord << 1), Endpoint_Read_16_LE());
 173                                 }
 174
 175                                 /* Write the filled FLASH page to memory */
 176                                 boot_page_write(PageAddress);
 177                                 boot_spm_busy_wait();
 178
 179                                 /* Re-enable RWW section */
 180                                 boot_rww_enable();
 181                         }
 182
 183                         Endpoint_ClearOUT();
 184
 185                         Endpoint_ClearStatusStage();
 186                         break;
 187         }
 188 }
 189