#include "uf2.h" #define SERIAL0 (*(uint32_t *)0x0080A00C) #define SERIAL1 (*(uint32_t *)0x0080A040) #define SERIAL2 (*(uint32_t *)0x0080A044) #define SERIAL3 (*(uint32_t *)0x0080A048) typedef struct { uint8_t JumpInstruction[3]; uint8_t OEMInfo[8]; uint16_t SectorSize; uint8_t SectorsPerCluster; uint16_t ReservedSectors; uint8_t FATCopies; uint16_t RootDirectoryEntries; uint16_t TotalSectors16; uint8_t MediaDescriptor; uint16_t SectorsPerFAT; uint16_t SectorsPerTrack; uint16_t Heads; uint32_t HiddenSectors; uint32_t TotalSectors32; uint8_t PhysicalDriveNum; uint8_t Reserved; uint8_t ExtendedBootSig; uint32_t VolumeSerialNumber; uint8_t VolumeLabel[11]; uint8_t FilesystemIdentifier[8]; } __attribute__((packed)) FAT_BootBlock; typedef struct { char name[8]; char ext[3]; uint8_t attrs; uint8_t reserved; uint8_t createTimeFine; uint16_t createTime; uint16_t createDate; uint16_t lastAccessDate; uint16_t highStartCluster; uint16_t updateTime; uint16_t updateDate; uint16_t startCluster; uint32_t size; } __attribute__((packed)) DirEntry; STATIC_ASSERT(sizeof(DirEntry) == 32); struct TextFile { const char name[11]; const char *content; }; #define STR0(x) #x #define STR(x) STR0(x) const char infoUf2File[] = // "UF2 Bootloader " UF2_VERSION "\r\n" "Model: " PRODUCT_NAME "\r\n" "Board-ID: " BOARD_ID "\r\n"; #if USE_FAT #if USE_INDEX_HTM const char indexFile[] = // "\n" "" "" "" "" "\n"; #endif // WARNING -- code presumes only one NULL .content for .UF2 file // and requires it be the last element of the array static const struct TextFile info[] = { {.name = "INFO_UF2TXT", .content = infoUf2File}, #if USE_INDEX_HTM {.name = "INDEX HTM", .content = indexFile}, #endif {.name = "CURRENT UF2"}, }; #define NUM_FILES (sizeof(info) / sizeof(info[0])) #define NUM_DIRENTRIES (NUM_FILES + 1) // Code adds volume label as first root directory entry #define UF2_SIZE (FLASH_SIZE * 2) #define UF2_SECTORS (UF2_SIZE / 512) #define UF2_FIRST_SECTOR (NUM_FILES + 1) // WARNING -- code presumes each non-UF2 file content fits in single sector #define UF2_LAST_SECTOR (UF2_FIRST_SECTOR + UF2_SECTORS - 1) #endif #define RESERVED_SECTORS 1 #define ROOT_DIR_SECTORS 4 #define SECTORS_PER_FAT ((NUM_FAT_BLOCKS * 2 + 511) / 512) #define START_FAT0 RESERVED_SECTORS #define START_FAT1 (START_FAT0 + SECTORS_PER_FAT) #define START_ROOTDIR (START_FAT1 + SECTORS_PER_FAT) #define START_CLUSTERS (START_ROOTDIR + ROOT_DIR_SECTORS) // all directory entries must fit in a single sector // because otherwise current code overflows buffer #define DIRENTRIES_PER_SECTOR (512/sizeof(DirEntry)) #if USE_FAT STATIC_ASSERT(NUM_DIRENTRIES < DIRENTRIES_PER_SECTOR * ROOT_DIR_SECTORS); #endif static const FAT_BootBlock BootBlock = { .JumpInstruction = {0xeb, 0x3c, 0x90}, .OEMInfo = "UF2 UF2 ", .SectorSize = 512, .SectorsPerCluster = 1, .ReservedSectors = RESERVED_SECTORS, .FATCopies = 2, .RootDirectoryEntries = (ROOT_DIR_SECTORS * DIRENTRIES_PER_SECTOR), .TotalSectors16 = NUM_FAT_BLOCKS - 2, .MediaDescriptor = 0xf0, // typical for unpartitioned disks .SectorsPerFAT = SECTORS_PER_FAT, .SectorsPerTrack = 1, .Heads = 1, .PhysicalDriveNum = 0x00, // to match MediaDescriptor of 0xf0 .ExtendedBootSig = 0x29, .VolumeSerialNumber = 0x00420042, .VolumeLabel = VOLUME_LABEL, .FilesystemIdentifier = "FAT16 ", }; void padded_memcpy(char *dst, const char *src, int len) { for (int i = 0; i < len; ++i) { if (*src) *dst = *src++; else *dst = ' '; dst++; } } void read_block(uint32_t block_no, uint8_t *data) { memset(data, 0, 512); uint32_t sectionIdx = block_no; if (block_no == 0) { // Requested boot block memcpy(data, &BootBlock, sizeof(BootBlock)); data[510] = 0x55; data[511] = 0xaa; // logval("data[0]", data[0]); } else if (block_no < START_ROOTDIR) { // Requested FAT table sector sectionIdx -= START_FAT0; // logval("sidx", sectionIdx); if (sectionIdx >= SECTORS_PER_FAT) sectionIdx -= SECTORS_PER_FAT; // second FAT is same as the first... #if USE_FAT if (sectionIdx == 0) { data[0] = 0xf0; // must match MediaDescriptor // WARNING -- code presumes only one NULL .content for .UF2 file // and all non-NULL .content fit in one sector // and requires it be the last element of the array for (int i = 1; i < NUM_FILES * 2 + 4; ++i) { data[i] = 0xff; } } for (int i = 0; i < 256; ++i) { // Generate the FAT chain for the firmware "file" uint32_t v = sectionIdx * 256 + i; if (UF2_FIRST_SECTOR <= v && v <= UF2_LAST_SECTOR) ((uint16_t *)(void *)data)[i] = v == UF2_LAST_SECTOR ? 0xffff : v + 1; } #else if (sectionIdx == 0) memcpy(data, "\xf0\xff\xff\xff", 4); #endif } #if USE_FAT else if (block_no < START_CLUSTERS) { // Requested sector of the root directory sectionIdx -= START_ROOTDIR; if (sectionIdx == 0) { DirEntry *d = (void *)data; padded_memcpy(d->name, BootBlock.VolumeLabel, 11); d->attrs = 0x28; for (int i = 0; i < NUM_FILES; ++i) { d++; const struct TextFile *inf = &info[i]; d->size = inf->content ? strlen(inf->content) : UF2_SIZE; d->startCluster = i + 2; padded_memcpy(d->name, inf->name, 11); d->createDate = 0x4d99; d->updateDate = 0x4d99; } } } else { // Requested sector from file space sectionIdx -= START_CLUSTERS; // WARNING -- code presumes all but last file take exactly one sector if (sectionIdx < NUM_FILES - 1) { memcpy(data, info[sectionIdx].content, strlen(info[sectionIdx].content)); } else { sectionIdx -= NUM_FILES - 1; uint32_t addr = sectionIdx * 256; if (addr < FLASH_SIZE) { UF2_Block *bl = (void *)data; bl->magicStart0 = UF2_MAGIC_START0; bl->magicStart1 = UF2_MAGIC_START1; bl->magicEnd = UF2_MAGIC_END; bl->blockNo = sectionIdx; bl->numBlocks = FLASH_SIZE / 256; bl->targetAddr = addr; bl->payloadSize = 256; bl->flags |= UF2_FLAG_FAMILYID_PRESENT; bl->familyID = UF2_FAMILY; memcpy(bl->data, (void *)addr, bl->payloadSize); } } } #endif } void write_block(uint32_t block_no, uint8_t *data, bool quiet, WriteState *state) { UF2_Block *bl = (void *)data; if (!is_uf2_block(bl) || !UF2_IS_MY_FAMILY(bl)) { return; } if ((bl->flags & UF2_FLAG_NOFLASH) || bl->payloadSize != 256 || (bl->targetAddr & 0xff) || bl->targetAddr < APP_START_ADDRESS || bl->targetAddr >= FLASH_SIZE) { #if USE_DBG_MSC if (!quiet) logval("invalid target addr", bl->targetAddr); #endif // this happens when we're trying to re-flash CURRENT.UF2 file previously // copied from a device; we still want to count these blocks to reset properly } else { // logval("write block at", bl->targetAddr); flash_write_row((void *)bl->targetAddr, (void *)bl->data); } if (state && bl->numBlocks) { if (state->numBlocks != bl->numBlocks) { if (bl->numBlocks >= MAX_BLOCKS || state->numBlocks) state->numBlocks = 0xffffffff; else state->numBlocks = bl->numBlocks; } if (bl->blockNo < MAX_BLOCKS) { uint8_t mask = 1 << (bl->blockNo % 8); uint32_t pos = bl->blockNo / 8; if (!(state->writtenMask[pos] & mask)) { // logval("incr", state->numWritten); state->writtenMask[pos] |= mask; state->numWritten++; } if (state->numWritten >= state->numBlocks) { // wait a little bit before resetting, to avoid Windows transmit error // https://github.com/Microsoft/uf2-samd21/issues/11 if (!quiet) resetHorizon = timerHigh + 30; // resetIntoApp(); } } } else { if (!quiet) resetHorizon = timerHigh + 300; } }