Correct me if I'm wrong but I thought all the data beyond IMAGE_SIZE remain intact by OpenWrt on firstboot. Experimenting with Archer C7 v1 recently I was able to flash OpenWrt image (ar71xx) and after reflashing tplink fw previous settings were still valid indicating config partition hasn't been overwritten. At least TL-MR22U has config partition of 64KB and Archer C7 has 128KB - I've gone through GPL sources of Archer and it seems between two firmware versions this partition was increased from 64 to 128KB, actually I discovered this by hexdiff-ing u-boot versions from each firmware version
On 07/08/2019, Adrian Schmutzler <m...@adrianschmutzler.de> wrote: >> -----Original Message----- >> From: openwrt-devel [mailto:openwrt-devel-boun...@lists.openwrt.org] On >> Behalf Of Tom Psyborg >> Sent: Mittwoch, 7. August 2019 17:58 >> To: Adrian Schmutzler <freif...@adrianschmutzler.de> >> Cc: openwrt-devel@lists.openwrt.org >> Subject: Re: [OpenWrt-Devel] [PATCH 2/3] ath79: fix IMAGE_SIZE for common >> TP-Link definitions >> >> Hi >> >> Looks like there were many doubts about image size over the years. >> >> One thing that should be considered is use of OEM firmware, either in >> case of just a single revert after OpenWrt flashing, or multiple >> reverts/switching between OEM/OpenWrt firmwares. >> >> Relevant in this case is config partition within OEM fw, and by >> specifying OpenWrt image size to occupy all available flash space >> between u-boot and art partitions destroys config contents which may >> turn up very impractical for those that do frequent switching between >> the two. >> >> Further, config partition size also varies from device to device, some >> have it 64KB others 128KB in size, at least what I observed with my >> devices. >> >> So, the correct image size for Archer C7 v1 turned out to be 0x7b0000 > > But wouldn't this call for introducing a config partition for the C7 v1? > I'm not sure how your analysis is affecting the IMAGE_SIZE discussion > (unless you say TP-Link devices generally have this config partition with > different sizes, and thus the whole concept of including IMAGE_SIZE in > common definitions is "wrong")... > > Best > > Adrian > _______________________________________________ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel
