From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-ob0-f173.google.com ([209.85.214.173]:34556 "EHLO mail-ob0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756616AbcARUar (ORCPT ); Mon, 18 Jan 2016 15:30:47 -0500 Received: by mail-ob0-f173.google.com with SMTP id vt7so170693023obb.1 for ; Mon, 18 Jan 2016 12:30:47 -0800 (PST) Subject: Re: Fwd: 8192 WiFi Realtek 8192E disconnects after a while and fails to reconnect To: Mateusz Kulikowski , gilbertdion@gmail.com, wlanfae@realtek.com, chaoming_li@realsil.com.cn References: <568EE125.1030103@gmail.com> <569C10A9.8020200@gmail.com> Cc: linux-wireless@vger.kernel.org From: Larry Finger Message-ID: <569D4B74.4040709@lwfinger.net> (sfid-20160118_213104_499919_FC956233) Date: Mon, 18 Jan 2016 14:30:44 -0600 MIME-Version: 1.0 In-Reply-To: <569C10A9.8020200@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 01/17/2016 04:07 PM, Mateusz Kulikowski wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA256 > > Hi Gilbert, > > Small update from my side - It took me a while to setup x86_64 machine, > but today was finally able to do test. > > > My result are the same as Larry: > I got my board running for ~4 hours and there was no disconnect. > For part of the time I was doing (some) activity, for around hour machine > was idle. > > I also did suspend-resume cycle. > > System: Ubuntu 15.04 (from usb stick), kernel 3.19.0-15-generic, x86_64 > Machine: MSI AM1I, Sempron 2650, > PCIe to mini-pcie "wifi" bridge (with antenna connector and proper RFKILL > wiring). > > > Are you able to do more troubleshooting? > > Perhaps try different AP/Channel/mode, (dis)connect power cable from laptop etc. > > I'll try to make another reproduction attempt, as without being able > to reproduce it I will probably not be able to fix it. The problem only shows up when you hit the NIC hard. Try downloading a large file while browsing. Some info from the Realtek engineer: ============================= About 92EE's 64 bit mode (PCI DAC), there are three roles -- (PCI host, PCI device, TRX desc). All possible combinations are: (32, 32, 32) (64, 64, 64) (32, 32, 64) <== special one To setup 64 bit mode, please use followings: 1. PCI host pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) 2. PCI device configuration space 0x719[5] = 1 indicate 64 bit mode 3. TRX desc register 0x382[15] = 1 indicate 64 bits mode If we turn on DMA_IS_64BIT, it will be the combination (32, 32, 64). It is rare to use because of 32 bit DMA address (SAC), but I think it will be work. We may extend DMA_IS_64BIT to the combination (64, 64, 64) to be meaningful. ============================= I did the easy step by effectively turning on DMA_IS_64BIT, and the driver failed. I have not had time to investigate any other of the 64-bit fixes. Larry