The uboot mapping is only 128KiB (0x20000) and not 2MiB (0x200000).
Dynamically adjust kernel and rootfs mappings based on the
geom_uncompress(4) magic.
This makes the built images more reliable by accepting changes on kernel
size transparently and matches the images built with zrouter and
freebsd-wifi-build.
Tested by: gjb
Approved by: adrian (mentor)
Obtained from: Zrouter
* Add the i2c bitbang bus;
* Add the etherswitch/rtl8366rb drivers;
* "fix" the USB GPIO configuration so USB actually works.
Submitted by: Stefan Bethke <stb@lassitu.de>
* Add in a default GPIO section for AR91XX_BASE.hints, which doesn't
define the GPIO function masks or any GPIO pines.
* Add in the GPIO line definitions for LEDs and GPIO pins for the
TP-WR1043nd.
I've verified the LEDs work fine using gpioset.
the second-last 64k seems to be the default firmware board configuration
area.
Since I have no idea whether uboot uses it or not - and it's prefixed
with an atheros eeprom signature (0xaa55), I figure the safest thing
to do is mark it as read-only.
I've modified my local tplink firmware building program to generate
a board configuration section - which is separate to this partition.
It's located in the 64k _before_ this particular 64k.
The firmware build program from OpenWRT never initialises those
values and the firmware images from tplink also leave it 0x0, so I
don't currently know what the exact, correct details should be.
The default flash layout gives only 1 megabyte for the kernel, gzipped.
The uboot firmware running on this device only supports gzip, not lzma, so
we actually _do_ have to try and slim the kernel down a bit.
But, since I can't actually do that at the present, I'm opting to:
* extend the kernel from 1mb to 2mb;
* have rootfs fill the rest of that, save 64k;
* eventually I'll hide a 64k config partition at the end, between the
end of rootfs and the ART (radio configuration data.)
The uboot firmware doesn't care about the partition layout. It just
expects the kernel application image to sit at 0xbf020000 (right after
the 128k uboot image.) The uboot header isn't actually read either -
it's "faked" from a "tplink" flash image header. So as long as the
map configuration here matches what is being written out via the
tplink firmware generator, everything is a-ok.
