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simmel-bootloader
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This commit is contained in:
Henry Gabryjelski 2019-03-12 12:29:05 -07:00
parent 12bb62eadd
commit e0251415e7
1 changed files with 8 additions and 8 deletions
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16
src/usb/uf2/ghostfat.c
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@ -177,30 +177,30 @@ void read_block(uint32_t block_no, uint8_t *data) {
memset(data, 0, 512);
uint32_t sectionIdx = block_no;
if (block_no == 0) {
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) {
} 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;
sectionIdx -= SECTORS_PER_FAT; // second FAT is same as the first...
if (sectionIdx == 0) {
data[0] = 0xf8;
data[0] = 0xf8; // first FAT entry must match BPB MediaDescriptor
for (int i = 1; i < NUM_INFO * 2 + 4; ++i) {
data[i] = 0xff;
}
}
for (int i = 0; i < 256; ++i) {
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 (block_no < START_CLUSTERS) {
} else if (block_no < START_CLUSTERS) { // Requested root directory sector
sectionIdx -= START_ROOTDIR;
if (sectionIdx == 0) {
if (sectionIdx == 0) { // only one sector of directory entries generated
DirEntry *d = (void *)data;
padded_memcpy(d->name, (char const *) BootBlock.VolumeLabel, 11);
d->attrs = 0x28;
@ -212,7 +212,7 @@ void read_block(uint32_t block_no, uint8_t *data) {
padded_memcpy(d->name, inf->name, 11);
}
}
} else {
} else { // else Generate the UF2 file data on-the-fly
sectionIdx -= START_CLUSTERS;
if (sectionIdx < NUM_INFO - 1) {
memcpy(data, info[sectionIdx].content, strlen(info[sectionIdx].content));