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-rw-r--r--.gitignore1
-rw-r--r--firmware/Makefile10
-rw-r--r--firmware/upgrade.c176
3 files changed, 186 insertions, 1 deletions
diff --git a/.gitignore b/.gitignore
index ec9d3aa..e0b0020 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
*.o
*.tmp
+*.raw
firmware/*.bin
commandline/littleWire_util.o
commandline/micronucleus
diff --git a/firmware/Makefile b/firmware/Makefile
index 996b08c..2e8eca8 100644
--- a/firmware/Makefile
+++ b/firmware/Makefile
@@ -190,7 +190,7 @@ read_fuses:
$(UISP) --rd_fuses
clean:
- @rm -f main.hex main.bin main.c.lst main.map *.o usbdrv/*.o main.s usbdrv/oddebug.s usbdrv/usbdrv.s main.lss
+ @rm -f main.hex main.bin main.c.lst main.map main.raw *.o usbdrv/*.o main.s usbdrv/oddebug.s usbdrv/usbdrv.s main.lss
# file targets:
main.bin: $(OBJECTS)
@@ -201,6 +201,14 @@ main.hex: main.bin
@avr-objcopy -j .text -j .data -O ihex main.bin main.hex
@avr-size main.bin
+upgrade: main.bin
+ avr-objcopy -O binary main.bin main.raw
+ avr-objcopy -I binary -O elf32-avr \
+ --rename-section .data=.text \
+ --redefine-sym _binary_main_raw_start=loader \
+ --redefine-sym _binary_main_raw_end=loader_end \
+ main.raw bootloader_linkable.o
+
disasm: main.bin
@avr-objdump -d -S main.bin >main.lss
diff --git a/firmware/upgrade.c b/firmware/upgrade.c
new file mode 100644
index 0000000..698ed28
--- /dev/null
+++ b/firmware/upgrade.c
@@ -0,0 +1,176 @@
+// Upgrade is an in-place firmware upgrader for tiny85 chips - just fill in the
+// 'bootloaderAddress' variable in bootloader_data.h, and the bootloaderData
+// progmem array with the bootloader data, and you're ready to go.
+//
+// Upgrade will firstly rewrite the interrupt vector table to disable the bootloader,
+// rewriting it to just run the upgrade app. Next it erases and writes each page of the
+// bootloader in sequence, erasing over any remaining pages leaving them set to 0xFFFF
+// Finally upgrader erases it's interrupt table again and fills it with RJMPs to
+// bootloaderAddress, effectively bridging the interrupts in to the new bootloader's
+// interrupts table.
+//
+// While upgrade has been written with attiny85 and micronucleus in mind, it should
+// work with other bootloaders and other chips with flash self program but no hardware
+// bootloader protection, where the bootloader exists at the end of flash
+//
+// Be very careful to not power down the AVR while upgrader is running.
+// If you connect a piezo between pb0 and pb1 you'll hear a bleep when the update
+// is complete. You can also connect an LED with pb0 positive and pb1 or gnd negative and
+// it will blink
+
+#include "./utils.h"
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <avr/pgmspace.h>
+#include <avr/wdt.h>
+#include <avr/boot.h>
+#include "./bootloader_data.c"
+
+void secure_interrupt_vector_table(void);
+void write_new_bootloader(void);
+void forward_interrupt_vector_table(void);
+void beep(void);
+void reboot(void);
+
+void load_table(uint16_t address, uint16_t words[SPM_PAGESIZE / 2]);
+void erase_page(uint16_t address);
+void write_page(uint16_t address, uint16_t words[SPM_PAGESIZE / 2]);
+
+
+int main(void) {
+ pinsOff(0xFF); // pull down all pins
+ outputs(0xFF); // all to ground - force usb disconnect
+ delay(250); // milliseconds
+ inputs(0xFF); // let them float
+ delay(250);
+ cli();
+
+ secure_interrupt_vector_table(); // reset our vector table to it's original state
+ write_new_bootloader();
+ forward_interrupt_vector_table();
+
+ beep();
+
+ reboot();
+
+ return 0;
+}
+
+// erase first page, removing any interrupt table hooks the bootloader added when
+// upgrade was uploaded
+void secure_interrupt_vector_table(void) {
+ uint16_t table[SPM_PAGESIZE / 2];
+
+ load_table(0, table);
+
+ // wipe out any interrupt hooks the bootloader rewrote
+ int i = 0;
+ while (i < SPM_PAGESIZE / 2) {
+ table[0] = 0xFFFF;
+ i++;
+ }
+
+ erase_page(0);
+ write_page(0, table);
+}
+
+// erase bootloader's section and write over it with new bootloader code
+void write_new_bootloader(void) {
+ uint16_t outgoing_page[SPM_PAGESIZE / 2];
+ int iter = 0;
+ while (iter < sizeof(bootloader_data)) {
+
+ // read in one page's worth of data from progmem
+ int word_addr = 0;
+ while (word_addr < SPM_PAGESIZE) {
+ int subaddress = ((int) bootloader_data) + iter + word_addr;
+ if (subaddress >= ((int) bootloader_data) + sizeof(bootloader_data)) {
+ outgoing_page[word_addr / 2] = 0xFFFF;
+ } else {
+ outgoing_page[word_addr / 2] = pgm_read_word(subaddress);
+ }
+
+ word_addr += 2;
+ }
+
+ // erase page in destination
+ erase_page(bootloader_address + iter);
+ // write updated page
+ write_page(bootloader_address + iter, outgoing_page);
+
+ iter += 64;
+ }
+}
+
+// write in forwarding interrupt vector table
+void forward_interrupt_vector_table(void) {
+ uint16_t vector_table[SPM_PAGESIZE / 2];
+
+ int iter = 0;
+ while (iter < SPM_PAGESIZE / 2) {
+ // rjmp to bootloader_address's interrupt table
+ vector_table[iter] = 0xC000 + (bootloader_address / 2) - 1;
+ iter++;
+ }
+
+ erase_page(0);
+ write_page(0, vector_table);
+}
+
+void load_table(uint16_t address, uint16_t words[SPM_PAGESIZE / 2]) {
+ uint16_t subaddress = 0;
+ address -= address % SPM_PAGESIZE; // round down to nearest page start
+
+ while (subaddress < SPM_PAGESIZE) {
+ words[subaddress / 2] = pgm_read_word(address + subaddress);
+ subaddress += 2;
+ }
+}
+
+void erase_page(uint16_t address) {
+ boot_page_erase(address - (address % SPM_PAGESIZE));
+ boot_spm_busy_wait();
+}
+
+void write_page(uint16_t address, uint16_t words[SPM_PAGESIZE / 2]) {
+ // fill buffer
+ uint16_t iter = 0;
+ while (iter < SPM_PAGESIZE / 2) {
+ boot_page_fill(address + (iter * 2), words[iter]);
+ iter++;
+ }
+
+ boot_page_write(address);
+ boot_spm_busy_wait(); // Wait until the memory is written.
+}
+
+// beep for a quarter of a second
+void beep(void) {
+ outputs(pin(0) | pin(1));
+ pinOff(1);
+
+ byte i = 0;
+ while (i < 250) {
+ delay(1);
+ pinOn(pin(0));
+ delay(1);
+ pinOff(pin(0));
+ i++;
+ }
+}
+
+void reboot(void) {
+ void (*ptrToFunction)(); // pointer to a function
+ ptrToFunction = 0x0000;
+ (*ptrToFunction)(); // reset!
+}
+
+
+////////////// Add padding to start of program so no program code could reasonably be erased while program is running
+// this never needs to be called - avr-gcc stuff happening: http://www.nongnu.org/avr-libc/user-manual/mem_sections.html
+volatile void FakeISR (void) __attribute__ ((naked)) __attribute__ ((section (".init0")));
+volatile void FakeISR (void) {
+ // 16 nops to pad out first section of program
+ asm("nop"); asm("nop"); asm("nop"); asm("nop"); asm("nop"); asm("nop"); asm("nop"); asm("nop");
+ asm("nop"); asm("nop"); asm("nop"); asm("nop"); asm("nop"); asm("nop"); asm("nop"); asm("nop");
+}