cannot enable power saving on wireless card

[Adel Ahmed]

I'm trying to turn on power saving for my wireless card(realtek8723BE):
localhost ~ # iwconfig wlan0 power off
Error for wireless request "Set Power Management" (8B2C) :
SET failed on device wlan0 ; Operation not supported.
localhost ~ # iwconfig wlan0 power on
Error for wireless request "Set Power Management" (8B2C) :
SET failed on device wlan0 ; Operation not supported.

also I cannot seem to find wlan0 when I build the modules in the kernel, the card works when its modules are modularized.


localhost ~ # lspci -s 04:00.0 -vvv
04:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter
Subsystem: Lenovo Device b728
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 18
Region 0: I/O ports at 4000 [size=256]
Region 2: Memory at f0100000 (64-bit, non-prefetchable) [size=16K]
Capabilities: [40] Power Management version 3
Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA PME(D0+,D1+,D2+,D3hot+,D3cold+)
Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [50] MSI: Enable- Count=1/1 Maskable- 64bit+
Address: 0000000000000000 Data: 0000
Capabilities: [70] Express (v2) Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <4us, L1 <64us
ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
MaxPayload 128 bytes, MaxReadReq 512 bytes
DevSta: CorrErr+ UncorrErr- FatalErr- UnsuppReq+ AuxPwr+ TransPend-
LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Latency L0 <512ns, L1 <64us
ClockPM+ Surprise- LLActRep- BwNot-
LnkCtl: ASPM L1 Enabled; RCB 64 bytes Disabled- Retrain- CommClk+
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
DevCap2: Completion Timeout: Not Supported, TimeoutDis+, LTR+, OBFF Via message/WAKE#
DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis+, LTR+, OBFF Disabled
LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance- SpeedDis-
Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
Compliance De-emphasis: -6dB
LnkSta2: Current De-emphasis Level: -6dB, EqualizationComplete-, EqualizationPhase1-
EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
Capabilities: [100 v2] Advanced Error Reporting
UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
AERCap: First Error Pointer: 00, GenCap+ CGenEn- ChkCap+ ChkEn-
Capabilities: [140 v1] Device Serial Number 00-23-b7-fe-ff-4c-e0-00
Capabilities: [150 v1] Latency Tolerance Reporting
Max snoop latency: 3145728ns
Max no snoop latency: 3145728ns
Capabilities: [158 v1] #1e
Kernel driver in use: rtl8723be
Kernel modules: rtl8723be

thanks

[apieum]

[Adel Ahmed]

localhost ~ # iw dev wlan0 set power_save on
command failed: Operation not supported (-95)


and I cannot find any NICs at all, except for eth0 and lo of course, so I don't think the network name rules are doing anything here

thanks

[apieum]

Hi and happy new year.

Can you show the result of:

[Adel Ahmed]

localhost ~ # modinfo rtl8723be
filename: /lib/modules/3.16.5-gentoo/kernel/drivers/net/wireless/rtlwifi/rtl8723be/rtl8723be.ko
firmware: rtlwifi/rtl8723befw.bin
description: Realtek 8723BE 802.11n PCI wireless
license: GPL
author: Realtek WlanFAE <wlanfae@realtek.com>
author: PageHe <page_he@realsil.com.cn>
alias: pci:v000010ECd0000B723sv*sd*bc*sc*i*
depends: rtlwifi,rtl8723-common,rtl_pci,btcoexist
intree: Y
vermagic: 3.16.5-gentoo SMP preempt mod_unload
parm: swlps:bool
parm: swenc:using hardware crypto (default 0 [hardware])
(bool)
parm: ips:using no link power save (default 1 is open)
(bool)
parm: fwlps:using linked fw control power save (default 1 is open)
(bool)
parm: msi:Set to 1 to use MSI interrupts mode (default 0)
(bool)
parm: debug:Set debug level (0-5) (default 0) (int)

I've tried changing the values in the power saving parameters, same result, same power drain(as reported by powertop
I've also checked the bios, nothing about powersaving

I'd rather update only when I have to, so I'll save that for last

thanks

[Adel Ahmed]

well, that link solved my other networking problem, no buffer space available(icmp)
disabling fwlps as stated in the link has fixed this problem. thanks alot for that.

[apieum]

I guess power management is managed by hardware and you'll not be able to control it.

You need to set ips parameter to 0 and swlps to 1.


Notes:
msi should probably set to 1 too but it's not in power management scope

For icmp, I guess your card support static SM power save.
You can check with "iw phy0 info"

[Adel Ahmed]

I now have:
Module: rtl8723be
Parameter: debug --> 0
Parameter: fwlps --> N
Parameter: ips --> N
Parameter: msi --> N
Parameter: swenc --> N
Parameter: swlps --> Y

but:
localhost ~ # iw dev wlan0 set power_save on
command failed: Operation not supported (-95)
localhost ~ # iwconfig wlan0 power off
Error for wireless request "Set Power Management" (8B2C) :
SET failed on device wlan0 ; Operation not supported.

the msi bit is interesting, I have been trying to understand this part, how does the NIC interrupt the CPU without MSI, and why is it better to enable msi?

I foudn this under capabilities:
Static SM Power Save, but what do you mean by for icmp?

thanks alot, I really appreciate your assistance

[apieum]

Sorry I've not seen you answered (browser cache).

[Adel Ahmed]

thanks alot, I appreciate your help

[apieum]

You're welcome.

You should try last firmware. (I suspect icmp errors comes from a firmware bug with power management)

As shown here your card firmware was updated the 09/13 and the last linux-firmware package in gentoo is 20140902.
You can enable linux-firmware 20141009 with accept keywords.


good luck.

[Adel Ahmed]

time to upgrade I guess