I read all the documentation about the flash modes.
I can tell you the following:
-I'm using ESP12F module with espressif logo not AI
-The esptool flash_id output is this :
Manufacturer: 20
Device: 4016
Detected flash size: 4MB
-esptool.py version 2.6
-About the flash size in esptool v2.6 the bit parameter was replaced with byte (32mb = 4MB)
-For the previous releases I had no problem with the parameters -fs 2MB-c1 -fm dio . Also v20 is working fine with -fs 4MB -fm qio
-I'm using rboot-config.bin found in the Release 17
-com port output 74880 baud for -fs 4MB -fm qio
ets Jan 8 2013,rst cause:1, boot mode:(3,7)
load 0x40100000, len 1628, room 16
tail 12
chksum 0xb8
ho 0 tail 12 room 4
load 0x3ffe8000, len 704, room 12
tail 4
chksum 0x90
csum 0x90
rBoot v1.4.2 - richardaburton@gmail.com
Flash Size: 32 Mbit
Flash Mode: QIO
Flash Speed: 40 MHz
rBoot Option: Big flash
rBoot Option: RTC data
Booting rom 0 at 2000, load addr 599e0.
sy�
thanks