[BPI-R2] internal Wifi/BT (MT6625L) - Kernel

I don’t mean recreating device. In my case i can’t restart hostapd, it restarts but doesn’t work. In general i don’t need to restart it, but looks like it’s a driver issue, as other wifi devices lets to restart hostapd and continue to work. In case of new setup it can be very useful: change password or channel.

Afair this was happening also in earlier versions of driver. But none had an idea why this happen. We have no support for the code which is large and dirty. a few users like lexa2 helped me to get it working in newer kernelversions or in better shape.

BTW, did someone tried to compile ti as a module? in this case it may be possible to reload module as some type of workaround.

Imho lexa did with last version. He fixed module build (merged to 5.4)…before it can’t be compiled as module.

I had kind-a-fixed driver code to be able to build it as a module but if I recall correctly it wasn’t providing much in terms of stability or alike. Problem was that having driver loaded as a module was mostly a one way road: attempts to unload and reload it might end up in kernel panics or in kernel memory corruption manifesting in things like sudden in-memory file system structures corruption with a subsequent loss of the data on the drive as soon as kernel decides to write corrupted structures to the disk. I hadn’t had any chance to work on anything R2 related since Nov 2019 so can’t provide you with more info than this.

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hi,

i’ve started work on 5.8 and currently hanging on cfg80211-api-change

6cd536fe62ef (“cfg80211: change internal management frame registration API”)

i hang here on converting mgmt_frame_register to update_mgmt_frame_registrations callbacks

i had already replaced the struct-entry and the function-headers, but i do not know how to get missing frame_type and reg resolved. Can i get the fields back out of the update-param? other drivers callbacks got completely rewritten, so i have no clue what to change

i have uploaded current state here:

maybe anyone here can help??

found this in johannes’ commit:

- if (frame_type == IEEE80211_STYPE_PROBE_REQ) {
- vif->probe_req_report = reg;
- }
+ vif->probe_req_report = upd->interface_stypes & BIT(IEEE80211_STYPE_PROBE_REQ >> 4);

This should be way to check frametype

It looks like frame_type can be extracted from upd->interface_stypes

This seems to be definition of bool reg:

struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
u32 preq_mask = BIT(IEEE80211_STYPE_PROBE_REQ >> 4);
bool global_change, intf_change;

intf_change = sdata->vif.probe_req_reg !=
			!!(upd->interface_stypes & preq_mask);

Bool Reg was true on register (cfg80211_mlme_register_mgmt) and false in unregister (cfg80211_process_mlme_unregistrations,removed)

Frametype was defined this way:

struct cfg80211_mgmt_registration *reg;
list_for_each_entry(reg, &wdev->mgmt_registrations, list) {
u16 frame_type = le16_to_cpu(reg->frame_type);

Where upd.interface_stypes is defined as this (combined with or over all wdev->mgmt_registrations).

BIT(le16_to_cpu(reg->frame_type) >> 4);

Problem i see is that only stypes passed in upd-struct,but not the needed frametypes MAC_FRAME_PROBE_REQ and MAC_FRAME_ACTION which are defined in drivers/misc/mediatek/connectivity/wlan/gen2/include/nic/mac.h

#define MAC_FRAME_TYPE_MGT                      0
#define MAC_FRAME_PROBE_REQ                     (MAC_FRAME_TYPE_MGT | 0x0040)
#define MAC_FRAME_ACTION                        (MAC_FRAME_TYPE_MGT | 0x00D0)

So we are still in the bits 4-7 (lower 4 bits zero which are shifted away in new version)…4=0100,D=1101, so it looks like it is a redefinition of the stypes (with combination)…if we shift back the stypes it can work…but because of combination of multiple registrations this can be wrong

And the new update-callback is called once and not like the old callback for each wdev->mgmt_registrations

I guess we need to loop again through all devs and regs

struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
struct wireless_dev *tmp;
struct cfg80211_mgmt_registration *reg;

	rcu_read_lock();
	list_for_each_entry_rcu(tmp, &rdev->wiphy.wdev_list, list) {
		list_for_each_entry_rcu(reg, &tmp->mgmt_registrations, list) {
			u32 frame_type = le16_to_cpu(reg->frame_type);
			bool reg = !!(frame_type & IEEE80211_STYPE_PROBE_REQ);
//put switch here...
}}
rcu_read_unlock();

This part of code was changed due to a locking bug…i guess i need to change it too

Maybe this is enough:

	struct cfg80211_mgmt_registration *reg;
	spin_lock_bh(&wdev->mgmt_registrations_lock);

	list_for_each_entry(reg, &wdev->mgmt_registrations, list) {
    		u16 frame_type = le16_to_cpu(reg->frame_type);
    		bool reg = !!(frame_type & IEEE80211_STYPE_PROBE_REQ);
		//put switch here...
	}
	spin_unlock_bh(&wdev->mgmt_registrations_lock);

But i guess it will fail on unregister, because list is freed before

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/net/wireless/mlme.c?#n624

Maybe the MAC_* can be directly converted to the stype value…

MAC_FRAME_PROBE_REQ = IEEE80211_STYPE_PROBE_REQ = 0x40

MAC_FRAME_ACTION = IEEE80211_STYPE_ACTION = 0xd0

The flags set here are defined here:

Guarded by CFG_ENABLE_WIFI_DIRECT_CFG_80211 which is set here with interesting comment above

And i found another interesting detail: https://github.com/frank-w/BPI-R2-4.14/blob/9ac31137c6b49dbc12d80de16ef0f455ffd94a3d/drivers/misc/mediatek/connectivity/wlan/gen2/include/config.h#L893 would it be possible to drop wmt-utils so easily?? But this will require combo-driver to be built as module to load firmware and config (where all options currently rejected so i made it optional in 5.8-wifi branch).

I tried to change the callback as far as i understand…i guess upd->interface_stypes is 0 on unregister

i changed code as far as i understand, can compile, boot without errors, can start AP and connect to it

can please others test?

Sure, I will test it.

I’d have to collect a second board somewhere next week, so it can take some time.

If you got a spare board you can test 5.8-rc tree where all so far is merged

Ok this weekend I tested the 5.8-rc branch and have some preliminary results:

I am running ArchlinuxARM and I’ve built the kernel in qemu on the same filesystem as I am running on the board.

[root@alarm ~]# uname -a
Linux alarm 5.8.0-rc4-bpi-r2+ #1 SMP Sat Jul 18 01:46:19 CEST 2020 armv7l GNU/Linux

So I’ve managed to start the AP, connect and route my connection to the internet. Very nice! Stopping hostapd and restarting it is not enough to make the AP reappear, but I’ve read before this is a known issue. At least a reboot fixes it.

More worrying is that i get intermittent crashes on several systemd services with various stacktraces:

[  319.167468] systemd[1]: systemd-logind.service: Killing process 378 (systemd-logind) with signal SIGABRT.
[  319.204724] systemd[1]: systemd-networkd.service: Killing process 363 (systemd-network) with signal SIGABRT.
[  319.268033] systemd[1]: systemd-udevd.service: Killing process 356 (systemd-udevd) with signal SIGABRT.

and errors:

[   15.180655] systemd-coredump[240]: #0  0x00000000b6cd6254 epoll_wait (libc.so.6 + 0xdd254)
[  240.140213] systemd-coredump[322]: #0  0x00000000b6d4fa1c __pthread_clockjoin_ex (libpthread.so.0 + 0x8a1c)
[  319.652388] systemd-coredump[398]: #0  0x00000000b6cce684 tcgetattr (libc.so.6 + 0xd4684)
[ Jul 18 01:39:58 alarm systemd-coredump[591]: #0  0x00000000b6c43210 epoll_wait (libc.so.6 + 0xdd210)
[  375.759007] systemd-coredump[1112]: #0  0x00000000b6ce49bc getxattr (libc.so.6 + 0xdc9bc)
[  375.782972] systemd-coredump[1112]: #1  0x00000000b6eb8ed4 fgetxattrat_fake (libsystemd-shared-245.so + 0x135ed4)

I’d have to dive in further to get some more info on why this happens.

dmesg.tgz (17.2 KB)

Take a look at my wifi.sh. i make a “echo 0 >wmtdevice” to reset the combo-chip.

For the crashes i have no idea yet…i had not seen them before.did you modified the config? How long had you your device running? Was that after the hostapd restart?

[   63.281186] [WMT-DEV][E]wmt_dev_read_file(1456):error code:-2
[   63.287078] [WMT-DEV][E]wmt_dev_patch_get(1573):load file (/system/etc/firmware/WMT_SOC.cfg) fail, iRet(-2)
[   63.296894] [WMT-CONF][E]wmt_conf_read_file(516):read /system/etc/firmware/WMT_SOC.cfg file fails

it looks like you don’t have the config-file…i did a basic patch that the kernel crashes not if this is missing, but maybe there is another access anywhere which affects your systemd. could you try adding the file in this location? it should not return with -2…the last message is ok, but before it looks wrong

Yes that works, after this hostapd can be restarted:

echo 0 > /dev/wmtWifi
echo A > /dev/wmtWifi

I didn’t have that file, after I added it that particular error disappeared and some new ones appear:

[   37.094342] [WMT-CONF][E]wmt_conf_parse_pair(323):unknown field 'mt6620.defAnt'.
[   37.110249] [WMT-CONF][E]wmt_conf_parse_pair(323):unknown field 'mt6628.defAnt'.
[   37.117693] [WMT-CONF][E]wmt_conf_parse_pair(323):unknown field 'mt6630.defAnt'.

It doesn’t seem important as WiFi just works.

I didn’t have time yet to look into the systemd issues, however I am sure they are unrelated to WiFi. I frequently get crashes, for example after login, when running ip addr, doing CTRL+C, or just doing nothing. The system keeps running without further issues, but it doesn’t give a lot of confidence with important services are crashing all the time.

My kernel config is just your config: mt7623n_evb_fwu_defconfig, no changes. If you are interested you can try my built kernel + modules. I will investigate more myself later.

Ok,then it is not related to the config file…but strange anyway because i have not seen it in my test.

now with 5.8-rc yes…in earlier versions kernel crashes at this point :wink:

Can you try running system with that kernel without enabling the wifi or just drop the driver from config…just to test if this is the issue?

It crashes regardless of WiFi, I am quite sure that WiFi is not the issue.

If you want you can try the kernel on your filesystem if you see similar issues (see previous post for link).

To be clear: They are only systemd crashes, no kernel oops or panic.

have you tested if an older kernel (maybe also from my repo) has no systemd-crashes? this looks not like an kernel-issue

it can be kernel-related (like hostapd info-messages), but i had not seen them on my box…which armbian have you installed?

Yes, kernel 4.14 works fine.

Maybe related: https://bugzilla.redhat.com/show_bug.cgi?id=1660466 ?

Can you test lts kernel 5.4 (maybe 4.19) and 5.7?

Hi, all!

I’ve installed 5.8-rc, looks fine, at least no problems in 2 hourssince R2 have booted it :slight_smile:

5.8-startup.txt (97.0 КБ)

Internal wifi works, and speed is the same (or very similar) to my previous 5.5, no disconnects.

Since i use gentoo i have no systemd, everything else forks just fine.

I’ll update this post on any errors/changes.

P.S. i have monitorless setup right now, so no hdmi/lima tests for a while.

have not ported lima changes yet to 5.8 (or any except 5.4). if i find more time, i can look for systemd-issue on my debian-system…maybe i have to let it run longer

UPD:

Full dmesg attached: 5.8-full-dmesg.txt (51.5 КБ)

Looks like there are some issues, and likely they related to my usb-wifi dongle driver - 88x2bu:

[   76.489024] ------------[ cut here ]------------
[   76.489048] WARNING: CPU: 1 PID: 6591 at net/wireless/nl80211.c:3301 nl80211_send_chandef+0x19c/0x1a4
[   76.489052] Modules linked in: xt_TCPMSS xt_tcpudp aes_arm_bs crypto_simd cryptd iptable_mangle xt_MASQUERADE iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_tables x_tables 88x2bu(O) mt76x2e mt76x2_common mt76x02_lib mt76
snd_soc_mt2701_afe snd_soc_mtk_common snd_soc_hdmi_codec snd_soc_core snd_pcm_dmaengine ac97_bus snd_pcm lima snd_timer snd gpu_sched soundcore mtk_thermal spi_mt65xx mtk_pmic_keys nvmem_mtk_efuse pwm_mediatek mt6577_auxadc msdos configfs fuse
f2fs xfs btrfs zstd_decompress zstd_compress xxhash
[   76.489129] CPU: 1 PID: 6591 Comm: RTW_CMD_THREAD Tainted: G           O      5.8.0-rc6-arm+ #1
[   76.489132] Hardware name: Mediatek Cortex-A7 (Device Tree)
[   76.489135] Backtrace:  
[   76.489148] [<c010e1dc>] (dump_backtrace) from [<c010e588>] (show_stack+0x20/0x24)
[   76.489156]  r7:00000ce5 r6:60040013 r5:00000000 r4:c1488b14
[   76.489164] [<c010e568>] (show_stack) from [<c059e81c>] (dump_stack+0xcc/0xe0)
[   76.489172] [<c059e750>] (dump_stack) from [<c012b8e0>] (__warn+0xe0/0x104)
[   76.489178]  r7:00000ce5 r6:c0c93e1c r5:00000009 r4:c1217ce0
[   76.489185] [<c012b800>] (__warn) from [<c012bca4>] (warn_slowpath_fmt+0x74/0xc4)
[   76.489192]  r7:00000ce5 r6:c1217ce0 r5:00000000 r4:e841a000
[   76.489200] [<c012bc34>] (warn_slowpath_fmt) from [<c0c93e1c>] (nl80211_send_chandef+0x19c/0x1a4)
[   76.489208]  r9:e8e2b000 r8:e841be88 r7:ffffffea r6:e841a000 r5:e86f9d80 r4:e841be88
[   76.489218] [<c0c93c80>] (nl80211_send_chandef) from [<c0c9bb68>] (nl80211_ch_switch_notify.constprop.0+0xd8/0x198)
[   76.489224]  r7:e8e2a800 r6:0000006e r5:e841a000 r4:e86f9d80
[   76.489234] [<c0c9ba90>] (nl80211_ch_switch_notify.constprop.0) from [<c0c9bc8c>] (cfg80211_ch_switch_started_notify+0x64/0xdc)
[   76.489242]  r10:00000000 r9:0000000b r8:e841bf08 r7:00000000 r6:e841be88 r5:e8e2b000
[   76.489245]  r4:e8e2a800
[   76.490351] [<c0c9bc28>] (cfg80211_ch_switch_started_notify) from [<bf5ae84c>] (rtw_cfg80211_ch_switch_notify+0xb8/0xd4 [88x2bu])
[   76.490361]  r8:e841bf08 r7:e841bf09 r6:00000001 r5:00000001 r4:f0d8c000
[   76.492470] [<bf5ae794>] (rtw_cfg80211_ch_switch_notify [88x2bu]) from [<bf552d1c>] (rtw_chk_start_clnt_join+0xa4/0x188 [88x2bu])
[   76.492478]  r5:f0d89000 r4:00000000
[   76.494566] [<bf552c78>] (rtw_chk_start_clnt_join [88x2bu]) from [<bf553060>] (join_cmd_hdl+0x260/0x35c [88x2bu])
[   76.494577]  r10:f0d89f30 r9:f0d89c05 r8:bf6ee6f8 r7:f0d89b1e r6:f0d896b1 r5:f0d896b2
[   76.494580]  r4:f0d89000
[   76.496682] [<bf552e00>] (join_cmd_hdl [88x2bu]) from [<bf51750c>] (rtw_cmd_thread+0x4e0/0x6e8 [88x2bu])
[   76.496693]  r9:bf6ee000 r8:bf552e00 r7:bf775888 r6:ffffa8b1 r5:f0d89000 r4:e911f880
[   76.497795] [<bf51702c>] (rtw_cmd_thread [88x2bu]) from [<c0152110>] (kthread+0x130/0x158)
[   76.497805]  r10:e7847424 r9:f0d89000 r8:bf51702c r7:e841a000 r6:e79a572c r5:e8ed6340
[   76.497810]  r4:e7847400
[   76.497819] [<c0151fe0>] (kthread) from [<c0100148>] (ret_from_fork+0x14/0x2c)
[   76.497824] Exception stack(0xe841bfb0 to 0xe841bff8)
[   76.497831] bfa0:                                     00000000 00000000 00000000 00000000
[   76.497838] bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[   76.497844] bfe0: 00000000 00000000 00000000 00000000 00000013 00000000
[   76.497851]  r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:c0151fe0
[   76.497855]  r4:e8ed6340 r3:00000029
[   76.498014] ---[ end trace 5df6f6c4ac52074b ]---
[   77.077057] IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready

dmesg seems clean withoun this module.