bootloader.cpp

00001 #include "mbed.h"
00002 #include "FreescaleIAP.h"
00003 
00004 //Could be nicer, but for now just erase all preceding sectors
00005 #define NUM_SECTORS        57
00006 #define TIMEOUT            10000000
00007 #define BUFFER_SIZE        16
00008 
00009 void setupserial();
00010 void write(char *value);
00011 
00012 __attribute__((section(".ARM.__at_0x50000"))) void bootloader(void)
00013 {
00014     SIM->SCGC6 |= SIM_SCGC6_FTF_MASK;                               //enable the Flash module clock
00015 
00016     setupserial();
00017     write("\n\n\rBootloader\r\n");
00018     write("Continue? (y/n)");
00019 
00020     //Wait until data arrived, if it is 'y', continue
00021     while(!(UART0->S1 & UART_S1_RDRF_MASK));
00022     if (UART0->D != 'y') {
00023        // NVIC_SystemReset();
00024         return;
00025     }
00026 
00027     //Erase all sectors we use for the user program
00028     write("Erasing sectors!\r\n");
00029     for (int i = 0; i<NUM_SECTORS; i++) {
00030         erase_sector(SECTOR_SIZE * i);
00031         write("erased sector\r\n");
00032     }
00033 
00034     write("Done erasing, send file!\r\n");
00035 
00036 
00037     char buffer[BUFFER_SIZE];
00038     uint32_t count = 0;
00039     uint8_t buffercount = 0;
00040     uint32_t timeout = 0;
00041 
00042     //Wait until data is sent
00043     while(!(UART0->S1 & UART_S1_RDRF_MASK));
00044 
00045     //Data receive loop
00046     while(1) {
00047         //Check if there is new data
00048         if (UART0->S1 & UART_S1_RDRF_MASK) {
00049             //Place data in buffer
00050             buffer[buffercount] = UART0->D;
00051             buffercount++;
00052 
00053             //Reset timeout
00054             timeout = 0;
00055 
00056             //We write per BUFFER_SIZE chars
00057             if (buffercount == BUFFER_SIZE) {
00058                 //NMI Handler is at bytes 8-9-10-11, we overwrite this to point to bootloader function
00059                 if (count == 0) {
00060                     buffer[8] = 0x01;
00061                     buffer[9] = 0x00;
00062                     buffer[10] = 0x01;
00063                     buffer[11] = 0x00;
00064                 }
00065 
00066                 //Program the buffer into the flash memory
00067                 if (program_flash(count, buffer, BUFFER_SIZE) != 0) {
00068                     write("Error!\r\n");
00069                     break;
00070                 }
00071 
00072                 //Reset buffercount for next buffer
00073                 write("#");
00074                 buffercount = 0;
00075                 count += BUFFER_SIZE;
00076             }
00077         } else {
00078             //No new data, increase timeout
00079             timeout++;
00080 
00081             //We have received no new data for a while, assume we are done
00082             if (timeout > TIMEOUT) {
00083                 //If there is data left in the buffer, program it
00084                 if (buffercount != 0) {
00085                     for (int i = buffercount; i<BUFFER_SIZE; i++) {
00086                         buffer[i] = 0xFF;
00087                     }
00088                     program_flash(count, buffer, BUFFER_SIZE);
00089                 }
00090                 break;          //We should be done programming :D
00091             }
00092         }
00093     }
00094     write("Done programming!\r\n");
00095     NVIC_SystemReset();
00096 
00097     //Shouldn't arrive here
00098     while(1);
00099 }
00100 
00101 __attribute__((section(".ARM.__at_0x50080"))) static void setupserial(void)
00102 {
00103     //Setup USBTX/USBRX pins (PTB16/PTB17)
00104     SIM->SCGC5 |= 1 << SIM_SCGC5_PORTB_SHIFT;
00105     PORTB->PCR[16] = (PORTB->PCR[16] & 0x700) | (3 << 8);
00106     PORTB->PCR[17] = (PORTB->PCR[17] & 0x700) | (3 << 8);
00107 
00108     //Setup UART (ugly, copied resulting values from mbed serial setup)
00109     SIM->SCGC4 |= SIM_SCGC4_UART0_MASK;
00110 
00111     UART0->BDH = 3;
00112     UART0->BDL = 13;
00113     UART0->C4 = 8;
00114     UART0->C2 = 12;  //Enables UART
00115 
00116 }
00117 
00118 __attribute__((section(".ARM.__at_0x500A0"))) static void write(char *value)
00119 {
00120     int i = 0;
00121     //Loop through string and send everything
00122     while(*(value+i) != '\0') {
00123         while(!(UART0->S1 & UART_S1_TDRE_MASK));
00124         UART0->D = *(value+i);
00125         i++;
00126     }
00127 }
00128