The Yafut tool now has limited capabilities for working on filesystem
images stored in regular files. This enables preparing Yaffs2 images
for devices with NOR flash using upstream Yaffs2 filesystem code instead
of the custom kernel2minor tool.
Since minimizing the size of the resulting filesystem image size is
important and upstream Yaffs2 code requires two allocator reserve blocks
to be available when writing a file to the filesystem, a trick is
employed while preparing an OpenWRT image: the blank filesystem image
that Yafut operates on initially contains two extra erase blocks that
are chopped off after the kernel file is written. This is safe to do
because Yaffs2 has a true log structure and therefore only ever writes
sequentially (and the size of the kernel file is known beforehand).
While the two extra erase blocks are necessary for writes, Yaffs2 code
seems to be perfectly capable of reading back files from a "truncated"
filesystem that does not contain these extra erase blocks.
In terms of image size, this new approach is only marginally worse than
the current kernel2minor-based one: specifically, upstream Yaffs2 code
needs to write three object headers (each of which takes up an entire
data chunk) when the kernel file is written to the filesystem:
- an object header for the kernel file when it is created,
- an object header for the root directory when the kernel file is
created,
- an updated object header for the kernel file when the latter is
fully written (so that its new size can be recorded).
kernel2minor only writes two of these headers, which is the absolute
minimum required for reading the file back. This means that the
Yafut-based approach causes firmware images to be at most one erase
block (64 kB) larger than those created using kernel2minor, but only in
the very unfortunate scenario where the size of the kernel file is
really close to a multiple of the erase block size.
The rest of the calculations performed when the empty filesystem image
is first prepared stems from the Yaffs2 layout used by MikroTik NOR
devices: each 65,536-byte erase block contains 63 chunks, each of which
consists of 1024 bytes of data followed by 16-byte Yaffs tags without
ECC data; each such group of 63 chunks is then followed by 16 bytes of
padding, which translates to "-C 1040 -B 64k -E" in the Yafut
invocation. Yaffs2 checkpoints and summaries are disabled (using
Yafut's -P and -S switches, respectively) as they are merely performance
optimizations that require extra storage space. The -L and -M switches
are used to force little-endian or big-endian byte order (respectively)
in the resulting filesystem image, no matter what byte order the build
host uses. The tr invocation is used to ensure that the filesystem
image is initialized with 0xFF bytes (which are an indicator of unused
space for Yaffs2 code).
Signed-off-by: Michał Kępień <openwrt@kempniu.pl>
Link: https://github.com/openwrt/openwrt/pull/13453
Signed-off-by: Robert Marko <robimarko@gmail.com>
Following 5264296, Mirotik NAND devices now use yafut to flash the
kernel on devices. This method is incompatible with the old-style
"kernel2minor" flash mechanism.
Even though NAND images were disabled in default build since 21.02, a
user flashing a new-style image onto an old-style image would result in
in a soft-brick[1]. In order to prevent such accidental mishap,
especially as these device images will be reenabled in the upcoming
release, bump the compat version.
After the new image is flashed, the compat version can be updated:
uci set system.@system[0].compat_version='1.1'
uci commit
[1] https://github.com/openwrt/openwrt/pull/12225#issuecomment-1517529262
Cc: Michał Kępień <openwrt@kempniu.pl>
Signed-off-by: Thibaut VARÈNE <hacks@slashdirt.org>
Reviewed-by: Robert Marko <robimarko@gmail.com>
Instead of erasing the entire NAND partition holding the kernel during
every system upgrade and then flashing a Yaffs file system image
prepared using kernel2minor (not accounting for bad blocks in the
process), use the Yafut utility to replace the kernel executable on
MikroTik NAND devices, preserving the existing Yaffs file system
(including bad block information) on the partition holding the kernel.
Add Yafut to DEFAULT_PACKAGES for the ath79/mikrotik target, so that the
tool is included in the initramfs images created when building for
multiple profiles. However, exclude Yafut from the images built for
MikroTik devices with NOR flash as the tool is currently only meant to
be used on devices with NAND flash.
As this addresses the concerns for MikroTik NAND devices discussed in
commit 9d96b6fb72 ("ath79/mikrotik: disable building NAND images"),
re-enable building images for these devices.
Signed-off-by: Michał Kępień <openwrt@kempniu.pl>
Return to using the OpenWrt kernel loader to decompress and load kernel
initram image.
Continue to use the vmlinuz kernel for squashfs.
Mikrotik's bootloader RouterBOOT on some ath79 devices is
failing to boot the current initram, due to the size of the initram image.
On the ath79 wAP-ac:
a 5.7MiB initram image would fail to boot
After this change:
a 6.6MiB initram image successfully loads
This partially reverts commit e91344776b.
An alternative of using RouterBOOT's capability of loading an initrd ELF
section was investigated, but the OpenWrt kernel loader allows larger image.
Signed-off-by: John Thomson <git@johnthomson.fastmail.com.au>
sysupgrade metadata is not flashed to the device, so check-size
should be called _before_ adding metadata to the image.
While at it, do some obvious wrapping improvements.
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
Acked-by: Paul Spooren <mail@aparcar.org>
The current support for MikroTik NAND-based devices relies on a
gross hack that packs the kernel into a static YAFFS stub, as the
stock bootloader only supports booting a YAFFS-encapsulated kernel.
The problem with this approach is that since the kernel partition is
blindly overwritten without any kind of wear or badblock management
(due to lack of proper support for YAFFS in OpenWRT), the NAND flash
is not worn uniformly and eventually badblocks appear, leading to
unbootable devices.
This issue has been reported here [1] and discussed in more detail
here [2].
[1] https://forum.openwrt.org/t/rb433-bad-sector-cannot-start-openwrt/71519
[2] https://github.com/openwrt/openwrt/pull/3026#issuecomment-673597461
Until a proper fix is found (or the stock bootloader supports other
filesystems), we disable building these images to prevent unknowing
users from risking their devices.
Thanks to Thibaut Varène for summarizing the details above.
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
- minimal built initramfs: 10MB vmlinux ELF -> 6MB vmlinuz
- ~5 seconds for kernel decompression, which was equivalent to the
additional time to load the uncompressed ELF from SPI NOR.
- Removes requirement for lzma-loader, which may have been causing some
image builds to fail to boot on Mikrotik mt7621.
Suggested-by: Thibaut VARÈNE <hacks@slashdirt.org>
Signed-off-by: John Thomson <git@johnthomson.fastmail.com.au>
Move the image preparation and nand-utils package selection into
common device definitions for NOR/NAND devices.
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
With the implementation of a sysfs interface to access WLAN data, this
target no longer needs a special wrapper to extract caldata.
Signed-off-by: Thibaut VARÈNE <hacks@slashdirt.org>
This commit adds support for the MikroTik RouterBOARD wAP G-5HacT2HnD
(wAP AC), a small weatherproof dual band, dual-radio 802.11ac
wireless AP with integrated omnidirectional anntennae and one
10/100/1000 Mbps Ethernet port.
See https://mikrotik.com/product/RBwAPG-5HacT2HnD for more info.
Specifications:
- SoC: Qualcomm Atheros QCA9556
- RAM: 64 MB
- Storage: 16 MB NOR
- Wireless:
· Atheros AR9550 (SoC) 802.11b/g/n 2x2:2, 2 dBi antennae
· Qualcomm QCA9880 802.11a/n/ac 3x3:3, 2 dBi antennae
- Ethernet: Atheros AG71xx (SoC, AR8033), 1x 1000/100/10 port,
passive PoE in
Working:
- Board/system detection
- Sysupgrade
- Serial console
- Ethernet
- 2.4 GHz radio
- 5 GHz radio and LED
- Reset button
Not working/Unsupported:
- 2.4 GHz LED
- AP/CAP LED
- ZT2046Q SPI temperature and voltage sensor
This adds the basic features for supporting MikroTik devices:
- a common recipe for mikrotik images in common-mikrotik.mk
- support for minor (MikroTik NOR) split firmware (only for
generic subtarget so far)
Acknowledgments: Robert Marko <robimarko@gmail.com>
Andrew Cameron <apcameron@softhome.net>
Koen Vandeputte <koen.vandeputte@ncentric.com>
Chuanhong Guo <gch981213@gmail.com>
Signed-off-by: Roger Pueyo Centelles <roger.pueyo@guifi.net>
Co-developed-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
