neiam /lambent-flex-c6

# Two app slots, so the device can write the one it is not running from.
#
# `nvs` keeps the offset AND size it had under espflash's default table
# (0x9000, 0x6000): changing either invalidates the stored blob, and this
# firmware keeps its wifi credentials and pin config there. The one-time USB
# migration onto this table is therefore not a reprovisioning.
#
# `otadata` fills the gap to 0x11000. App partitions must start on a 64KB
# boundary, hence ota_0 at 0x20000 rather than immediately after — the 60KB
# that leaves is the price of not touching nvs. That alignment is also what
# keeps the MMU-page rule satisfied (see CLAUDE.md, "Flash size is
# load-bearing"): with 4MB flash the pages are 64KB, and both slots are
# 64KB-aligned, so `vaddr % page == offset % page` holds for either.
#
# 0x1F0000 = 1984KB per slot, against a ~1.51MB image (TLS and the certificate
# bundle are most of the difference from the pre-OTA 1.10MB). ota_1 ends at
# 0x400000, exactly the 4MB part: there is nothing else to spend the rest on,
# and a bigger slot is worth more than a spare region nothing addresses.
#
# Watch this number. `espflash save-image` prints the image against the slot on
# every build and CI fails the build if it stops fitting.
#
# Name,     Type, SubType, Offset,   Size,     Flags
nvs,        data, nvs,     0x9000,   0x6000,
otadata,    data, ota,     0xf000,   0x2000,
ota_0,      app,  ota_0,   0x20000,  0x1F0000,
ota_1,      app,  ota_1,   0x210000, 0x1F0000,