Currently it's not possible to flash factory images on devices shipped
with vendor firmware versions 1.1.0 Build 20201120 rel. 50406 (published
2020-12-22):
(curFw_ver, newFw_ver) == (1.1, 1.0) [NM_Error](nm_checkSoftVer) 00848: Firmwave not supports, check failed.
[NM_Error](nm_checkUpdateContent) 01084: software version dismatched
[NM_Error](nm_buildUpgradeStruct) 01188: checkUpdateContent failed.
They've even following note in release notes:
Note: You will be unable to downgrade to the previous firmware version
after updating this firmware.
This version check in vendor firmware is implemented in
/usr/bin/nvrammanager binary likely as following C code[1]:
sscanf(buf, "%d.%d.%*s",&upd_fw_major, &upd_fw_minor);
...
if (((int)upd_fw_major < (int)cur_fw_major) ||
((ret = 1, cur_fw_major == upd_fw_major && (upd_fw_minor < (int)cur_fw_minor)))) {
ret = 0;
printf("[NM_Error](%s) %05d: Firmwave not supports, check failed.\r\n\r\n","nm_checkSoftVer" ,0x350);
}
...
return ret;
So in order to fix this and make it future proof it should be enough to
ship our factory firmware images with major version 7 (lucky number).
Tested on latest firmware version 1.1.2 Build 20210125 rel.37999:
Firmwave supports, check OK.
(curFw_ver, newFw_ver) == (1.1, 7.0) check firmware ok!
Flashing back to vendor firmware
c7v5_us-up-ver1-1-2-P1[20210125-rel37999]_2021-01-25_10.33.55.bin works
as well:
U-Boot 1.1.4-gbec22107-dirty (Nov 18 2020 - 18:19:12)
...
Firmware downloaded... filesize = 0xeeae77 fileaddr = 0x80060000.
Firmware Recovery file length : 15642231
Firmware process id 2.
handle_fw_cloud 146
Image verify OK!
Firmware file Verify ok!
product-info:product_name:Archer C7
product_ver:5.0.0
special_id:55530000
[Error]sysmgr_cfg_checkSupportList(): 1023 @ specialId 45550000 NOT Match.
Firmware supports, check OK.
Firmware Recovery check ok!
1. https://gist.github.com/ynezz/2e0583647d863386a66c3d231541b6d1
Signed-off-by: Petr Štetiar <ynezz@true.cz>
e6d66375cb