diff options
Diffstat (limited to 'bootloader/main.cpp')
| -rw-r--r-- | bootloader/main.cpp | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/bootloader/main.cpp b/bootloader/main.cpp new file mode 100644 index 0000000..620e143 --- /dev/null +++ b/bootloader/main.cpp @@ -0,0 +1,323 @@ +#include <rcc/rcc.h> +#include <rcc/flash.h> +#include <gpio/gpio.h> +#include <interrupt/interrupt.h> +#include <os/time.h> +#include <usb/usb.h> +#include <usb/descriptor.h> +#include <usb/hid.h> + +static uint32_t& reset_reason = *(uint32_t*)0x10000000; +static const uint32_t* firmware_vtors = (uint32_t*)0x8002000; + +static bool do_reset; + +void reset() { + SCB.AIRCR = (0x5fa << 16) | (1 << 2); // SYSRESETREQ +} + +void chainload(uint32_t offset) { + SCB.VTOR = offset; + + asm volatile("ldr sp, [%0]; ldr %0, [%0, #4]; bx %0" :: "r" (offset)); +} + +auto report_desc = pack( + usage_page(0xff55), + usage(0xb007), + collection(Collection::Application, + logical_minimum(0), + logical_maximum(255), + report_size(8), + report_count(1), + + usage(0xb007), + input(0x02), // Status + + usage(0xb007), + feature(0x02), // Function + + usage(0xb007), + report_count(64), + output(0x02) // Data + ) +); + +auto dev_desc = device_desc(0x200, 0, 0, 0, 64, 0x1d50, 0x6084, 0x110, 1, 2, 3, 1); +auto conf_desc = configuration_desc(1, 1, 0, 0xc0, 0, + // HID interface. + interface_desc(0, 0, 1, 0x03, 0x00, 0x00, 0, + hid_desc(0x111, 0, 1, 0x22, sizeof(report_desc)), + endpoint_desc(0x81, 0x03, 64, 1) + ) +); + +desc_t dev_desc_p = {sizeof(dev_desc), (void*)&dev_desc}; +desc_t conf_desc_p = {sizeof(conf_desc), (void*)&conf_desc}; +desc_t report_desc_p = {sizeof(report_desc), (void*)&report_desc}; + +static Pin usb_dm = GPIOA[11]; +static Pin usb_dp = GPIOA[12]; +static Pin usb_pu = GPIOA[15]; + +static PinArray button_inputs = GPIOB.array(0, 10); +static PinArray button_leds = GPIOC.array(0, 10); + +static Pin led1 = GPIOA[8]; +static Pin led2 = GPIOA[9]; + +USB_f1 usb(USB, dev_desc_p, conf_desc_p); + +class Flashloader { + private: + bool state; + uint32_t addr; + + public: + Flashloader() : state(false) {} + + bool prepare() { + addr = 0x8002000; + state = true; + + // Unlock flash. + FLASH.KEYR = 0x45670123; + FLASH.KEYR = 0xCDEF89AB; + + return true; + } + + bool write_block(uint32_t size, void* data) { + if(!state) { + return false; + } + + if(size & 1) { + return false; + } + + if(addr + size > 0x8020000) { + return false; + } + + if(!(addr & (2048 - 1))) { + // Erase page. + + FLASH.CR = 1 << 1; // PER + FLASH.AR = addr; + FLASH.CR = (1 << 6) | (1 << 1); // STRT, PER + + while(FLASH.SR & (1 << 0)); // BSY + + FLASH.SR &= ~(1 << 5); // EOP + FLASH.CR = 0; + } + + uint16_t* src = (uint16_t*)data; + uint16_t* dest = (uint16_t*)addr; + + for(uint32_t n = 0; n < size; n += 2) { + FLASH.CR = 1 << 0; // PG + + *dest++ = *src++; + + while(FLASH.SR & (1 << 0)); // BSY + } + + + addr += size; + return true; + } + + bool finish() { + state = false; + + FLASH.CR = 1 << 7; // LOCK + + return true; + } +}; + +Flashloader flashloader; + +class HID_bootloader : public USB_HID { + public: + HID_bootloader(USB_generic& usbd, desc_t rdesc) : USB_HID(usbd, rdesc, 0, 1, 64) {} + + protected: + virtual bool set_output_report(uint32_t* buf, uint32_t len) { + if(len != 64) { + return false; + } + + return flashloader.write_block(len, buf); + } + + virtual bool set_feature_report(uint32_t* buf, uint32_t len) { + if(len != 1) { + return false; + } + + switch(*buf & 0xff) { + case 0: + return true; + + case 0x10: // Reset to bootloader + return false; // Not available in bootloader mode + + case 0x11: // Reset to runtime + do_reset = true; + return true; + + case 0x20: // Flash prepare + return flashloader.prepare(); + + case 0x21: // Flash finish + return flashloader.finish(); + + default: + return false; + } + } +}; + +HID_bootloader usb_hid(usb, report_desc_p); + +uint32_t serial_num() { + uint32_t* uid = (uint32_t*)0x1ffff7ac; + + return uid[0] * uid[1] * uid[2]; +} + +class USB_strings : public USB_class_driver { + private: + USB_generic& usb; + + public: + USB_strings(USB_generic& usbd) : usb(usbd) { + usb.register_driver(this); + } + + protected: + virtual SetupStatus handle_setup(uint8_t bmRequestType, uint8_t bRequest, uint16_t wValue, uint16_t wIndex, uint16_t wLength) { + // Get string descriptor. + if(bmRequestType == 0x80 && bRequest == 0x06 && (wValue & 0xff00) == 0x0300) { + const void* desc = nullptr; + uint16_t buf[9]; + + switch(wValue & 0xff) { + case 0: + desc = u"\u0304\u0409"; + break; + + case 1: + desc = u"\u0308zyp"; + break; + + case 2: + desc = u"\u0322arcin bootloader"; + break; + + case 3: + { + buf[0] = 0x0312; + uint32_t id = serial_num(); + for(int i = 8; i > 0; i--) { + buf[i] = (id & 0xf) > 9 ? 'A' + (id & 0xf) - 0xa : '0' + (id & 0xf); + id >>= 4; + } + desc = buf; + } + break; + } + + if(!desc) { + return SetupStatus::Unhandled; + } + + uint8_t len = *(uint8_t*)desc; + + if(len > wLength) { + len = wLength; + } + + usb.write(0, (uint32_t*)desc, len); + + return SetupStatus::Ok; + } + + return SetupStatus::Unhandled; + } +}; + +USB_strings usb_strings(usb); + +bool normal_boot() { + // Check if this was a reset-to-bootloader. + if(reset_reason == 0xb007) { + reset_reason = 0; + return false; + } + + // Check buttons. + if((button_inputs.get() ^ 0x7ff) == ((1 << 1) | (1 << 0))) { + return false; + } + + // Check that reset vector is a valid flash address. + uint32_t reset_vector = firmware_vtors[1]; + if(reset_vector < 0x8002000 || reset_vector >= 0x8020000) { + return false; + } + + // No reason to enter bootloader. + return true; +} + +int main() { + RCC.enable(RCC.GPIOA); + RCC.enable(RCC.GPIOB); + RCC.enable(RCC.GPIOC); + + button_inputs.set_mode(Pin::Input); + button_inputs.set_pull(Pin::PullUp); + + button_leds.set_mode(Pin::Output); + + led1.set_mode(Pin::Output); + led2.set_mode(Pin::Output); + + if(normal_boot()) { + chainload(0x8002000); + } + + rcc_init(); + + // Initialize system timer. + STK.LOAD = 72000000 / 8 / 1000; // 1000 Hz. + STK.CTRL = 0x03; + + usb_dm.set_mode(Pin::AF); + usb_dm.set_af(14); + usb_dp.set_mode(Pin::AF); + usb_dp.set_af(14); + + RCC.enable(RCC.USB); + + usb.init(); + + usb_pu.set_mode(Pin::Output); + usb_pu.on(); + + + while(1) { + usb.process(); + + if(do_reset) { + Time::sleep(10); + reset(); + } + + GPIOC[0].set(Time::time() & 512); + } +} |