Hi Russel, > -----Original Message----- > From: Russell King - ARM Linux [mailto:li...@armlinux.org.uk] > Sent: Saturday, October 14, 2017 2:30 PM > To: Reizer, Eyal > Cc: linux-wireless@vger.kernel.org; Altshul, Maxim; Narang, Saurabh > Subject: Re: wl1837: poor performance? > > On Fri, Oct 13, 2017 at 07:43:37AM +0000, Reizer, Eyal wrote: > > Sorry for top posting. > > Signal level on wlan0 seems low (-79 dbm) are you sure there are antennas > > connected? > > Thanks for the reply. > > In development environments, it's common to have the AP and station > nearby, which will give good signal. Out of the development > environment, the AP and station may be separated by several 10s of ft > and objects in the way. That's the case here, so about -80dBm is to > be expected. > > As I mentioned, there's two stations each with different chipsets, both > with the same signal level being reported, both at a similar distance > from the AP, but one performs way better than the other. I've found > the reason for this (see below.) > > I should also mention that this is installed remotely, and I'm debugging > it over the 'net, involving this very Wi-Fi connection. > > The radio environment is not excessively populated - both systems are > within a tower with >2ft thick stone and lime mortar walls which radio > has difficulty penetrating, which is itself in a park with very few > other buildings around. I'm using the 2.4G channel 8, I've seen some > other APs on channel 1 when outside but almost never inside the tower. > > nmcli (used to?) occasionally reports that the wl1837 can see another > AP ("CARWIFI") on channel 1, but that's rare - I suspect it requires > someone to park their car in direct line of literal sight through a > tower window from the machine. I suspect NM noticed that before I > configured the BSSID of the associated AP as I haven't recently > noticed NM reporting any other networks. Could also be that non-wifi > enabled cars are parked in those spaces! > > > In addition what type of module is used here? > > It's a WL1837 integrated onto SolidRun's iMX6 microsom. I'm not sure > what other information in terms of "module" you're asking for.
Do you know what type of wilink8 module is installed with this SOM board? Is it a TI module similar to this one?: http://www.ti.com/lit/ds/symlink/wl1837mod.pdf > > > Di you use the configure_device.sh scripts as documented in the > > "wlconf" manual? > > No, because quite honestly the wilink tooling is something of a mess > in terms of trying to find the right tooling. This is what I ended > up doing: Wlconf should be taken from: https://git.ti.com/wilink8-wlan/18xx-ti-utils/trees/R8.7_SP2 I think you have used something a bit outdated. You can see the following wiki for building all latest components: http://processors.wiki.ti.com/index.php/WL18xx_System_Build_Scripts You can use the build script for building just the "utils" part if you just need wlconf. You can also use the git above directly. Once elconf is build and installed you will see the following script in your rootfs: https://git.ti.com/wilink8-wlan/18xx-ti-utils/blobs/R8.7_SP2/wlconf/configure-device.sh That you just need to run once, answering the relevant questions and it will create wl18xx-conf.bin for you. There is no need for manually editing any files. See the following document as well: http://www.ti.com/lit/an/swra489/swra489.pdf You can follow section 2 of this document. > > 1. cloning git://github.com/TI-OpenLink/18xx-ti-utils > 2. taking the wl18xx driver default configuration (from debugfs). > 3. taking the ti wilink driver conf.h files. > 4. massaging the conf.h files into a form that wlconf can read > 5. generating a new struct.bin > 6. changing: > wl18xx.phy.number_of_assembled_ant2_4 = 0x01 > wl18xx.phy.number_of_assembled_ant5 = 0x00 > > since this variant of the microsom I have only populates one antenna. > (The layout allows for the design to be extended to a second antenna.) > > I've since found the _right_ repository for the tooling > (git://git.ti.com/wilink8-wlan/18xx-ti-utils.git), and compared the > resulting files, and confirmed that my new struct.bin is identical to > the one in the right repository. > > There are some differences between the two files (- = mine, > + = configure_device.sh generated): > > -core.sg.params = 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x000000aa, 0x00000032, > 0x00000000, 0x00000000, 0x00000000, 0x000000c8, 0x00000000, 0x00000000, > 0x00000000, 0x00000001, 0x00000000, 0x0000003c, 0x00000000, 0x000004b0, > 0x00000000, 0x00000001, 0x00000003, 0x00000006, 0x00000000, 0x00000000, > 0x00000002, 0x00000000, 0x00000000, 0x00000003, 0x00000000, 0x00000002, > 0x0000001e, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000 > +core.sg.params = 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x0000000f, 0x0000001b, 0x00000011, 0x000000aa, 0x00000032, > 0x00000064, 0x00000320, 0x000000c8, 0x000000c8, 0x00000000, 0x00000000, > 0x00000000, 0x00000001, 0x00000000, 0x0000003c, 0x00001388, 0x000004b0, > 0x000003e8, 0x00000001, 0x00000003, 0x00000006, 0x0000000a, 0x0000000a, > 0x00000002, 0x00000005, 0x0000001e, 0x00000003, 0x0000000a, 0x00000002, > 0x00000000, 0x00000019, 0x00000019, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, > 0x00000000, 0x00000000, 0x00000000 > -core.conn.dynamic_ps_timeout = 0x05dc > +core.conn.dynamic_ps_timeout = 0x0096 > -core.sched_scan.num_short_intervals = 0x0e > +core.sched_scan.num_short_intervals = 0x0d > -core.fwlog.mem_blocks = 0x00 > +core.fwlog.mem_blocks = 0x02 > -wl18xx.ap_sleep.max_stations_thresh = 0x00 > -wl18xx.ap_sleep.idle_conn_thresh = 0x00 > +wl18xx.ap_sleep.max_stations_thresh = 0x04 > +wl18xx.ap_sleep.idle_conn_thresh = 0x08 > > The core.sg.param differences in an easier to read format are: > mine configure_device.sh > [23] 0x00000000 => 0x0000000f WL18XX_CONF_SG_PARAM_23 > [24] 0x00000000 => 0x0000001b WL18XX_CONF_SG_PARAM_24 > [25] 0x00000000 => 0x00000011 WL18XX_CONF_SG_PARAM_25 > [28] 0x00000000 => 0x00000064 WL18XX_CONF_SG_PARAM_28 > [29] 0x00000000 => 0x00000320 WL18XX_CONF_SG_PARAM_29 > [30] 0x00000000 => 0x000000c8 WL18XX_CONF_SG_PARAM_30 > [38] 0x00000000 => 0x00001388 WL18XX_CONF_SG_PARAM_38 > [40] 0x00000000 => 0x000003e8 WL18XX_CONF_SG_UNUSED > [44] 0x00000000 => 0x0000000a WL18XX_CONF_SG_PARAM_44 > [45] 0x00000000 => 0x0000000a WL18XX_CONF_SG_PARAM_45 > [47] 0x00000000 => 0x00000005 WL18XX_CONF_SG_GEMINI_PARAM_47 > [48] 0x00000000 => 0x0000001e > WL18XX_CONF_SG_STA_CONNECTION_PROTECTION_TIME > [50] 0x00000000 => 0x0000000a WL18XX_CONF_SG_PARAM_50 > [52] 0x0000001e => 0x00000000 > WL18XX_CONF_SG_AP_CONNECTION_PROTECTION_TIME > [53] 0x00000000 => 0x00000019 WL18XX_CONF_SG_PARAM_53 > [54] 0x00000000 => 0x00000019 WL18XX_CONF_SG_PARAM_54 > You don't normally need to change anything, especially as you are using a standard wl18xx module. > In any case, I eventually tracked down the reason for the 10ms pings - it > seems the iMX6 host SDHCI aggressively enters PM, with the autosuspend > delay is set to 50ms. Disabling runtime PM on the host results in ping > times around what I would expect - between 2 to 4ms. > > > In addition, for the recovery. Are you using latest firmware (8.9.0.0.70)? > > I'm using 8.9.0.0.75, which seems to be the latest as of 19th June, > which came from https://git.ti.com/wilink8-wlan/wl18xx_fw > Yes, you are using latest firmware. > The recovery doesn't seem to be a regular thing - I've only seen it > once so far, and it was non-fatal. Can you send us the recovery log next time you see it? It is not fatal as you have noted but still Should be very rare and interesting for us to see if there is any meaningful information there. > > > However, I have one lingering difference between the wl1837 and rtl8192eu > stations. If I set both up identically - with a BSS MAC address, thus > telling them that they should only associate with an AP with that MAC, > I find that rtl8192eu doesn't go off-channel to scan for APs, and has > pretty a stable ping RTT. > > However, the wl1837 seems to end up with a ping RTT of about 110ms every > 32s or so. I tried increasing "core.sched_scan.long_interval" in the > conf file to 40000, and this seemed to increase this to about once every > 50s. > > I've tried disabling the scheduled scan code in the wl18xx driver, but > that doesn't seem to have made a difference. I've also tried telling > wpa_supplicant not to scan (wpa_cli set pon) but that also doesn't seem > to make a difference. I don't think it's NetworkManager triggering the > scans, as both the wl1837 and rtl8192eu are setup identically, and > stracing NM only shows it polling for the signal level/bit rate etc - > and from what I read, configuring the connection with a BSSID stops > NM scanning for roaming. > I don't think you need to change these values. Your issue should not be related to these settings. > It doesn't seem to be causing a problem, but it would be nice to get > rid of the additional latency if possible. Obviously, it does need > to scan initially, so NM/wpa_supplicant can associate with the AP. > > With "core.sched_scan.long_interval" set back to 30000, and the > scheduled scan code in the wl18xx driver disabled, I'm seeing: > > 64 bytes from 192.168.250.1: icmp_seq=25 ttl=64 time=2.68 ms > 64 bytes from 192.168.250.1: icmp_seq=26 ttl=64 time=114 ms > 64 bytes from 192.168.250.1: icmp_seq=27 ttl=64 time=3.58 ms > ... > 64 bytes from 192.168.250.1: icmp_seq=65 ttl=64 time=2.58 ms > 64 bytes from 192.168.250.1: icmp_seq=66 ttl=64 time=107 ms > 64 bytes from 192.168.250.1: icmp_seq=67 ttl=64 time=2.71 ms > ... > 64 bytes from 192.168.250.1: icmp_seq=105 ttl=64 time=3.04 ms > 64 bytes from 192.168.250.1: icmp_seq=106 ttl=64 time=110 ms > 64 bytes from 192.168.250.1: icmp_seq=107 ttl=64 time=3.42 ms > ... > 64 bytes from 192.168.250.1: icmp_seq=145 ttl=64 time=3.18 ms > 64 bytes from 192.168.250.1: icmp_seq=146 ttl=64 time=109 ms > 64 bytes from 192.168.250.1: icmp_seq=147 ttl=64 time=3.27 ms > > Any ideas? > Two suggestions: Are you seeing this if disabling power save: iw wlan0 set power_save off Maybe unrelated, but can you also check if your kernel is configured with the following TCP congestion settings: CONFIG_TCP_CONG_ADVANCED=y CONFIG_DEFAULT_RENO=y CONFIG_DEFAULT_TCP_CONG="reno" This has helped customers in the past using latest kernels that had TCP unstable performance issues. Best Regards, Eyal
