From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B08E8C433EF for ; Tue, 23 Nov 2021 15:39:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238474AbhKWPmK (ORCPT ); Tue, 23 Nov 2021 10:42:10 -0500 Received: from mga07.intel.com ([134.134.136.100]:54611 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238499AbhKWPmI (ORCPT ); Tue, 23 Nov 2021 10:42:08 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10176"; a="298452739" X-IronPort-AV: E=Sophos;i="5.87,258,1631602800"; d="scan'208";a="298452739" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2021 07:39:00 -0800 X-IronPort-AV: E=Sophos;i="5.87,258,1631602800"; d="scan'208";a="674502303" Received: from smile.fi.intel.com ([10.237.72.184]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2021 07:38:58 -0800 Received: from andy by smile.fi.intel.com with local (Exim 4.95) (envelope-from ) id 1mpXsk-009ofI-V4; Tue, 23 Nov 2021 17:38:54 +0200 Date: Tue, 23 Nov 2021 17:38:54 +0200 From: Andy Shevchenko To: Jay Dolan Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Jiri Slaby Subject: Re: [PATCH v1 0/2] serial: 8250_pci: Split Pericom driver Message-ID: References: <20211117145750.43911-1-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 23, 2021 at 07:02:44AM -0800, Jay Dolan wrote: > On 11/23/21 1:25 AM, Andy Shevchenko wrote: > > On Mon, Nov 22, 2021 at 09:19:09PM -0800, Jay Dolan wrote: > > > On 11/22/21 4:48 AM, Andy Shevchenko wrote: > > > > On Mon, Nov 22, 2021 at 02:47:20PM +0200, Andy Shevchenko wrote: > > > > > On Thu, Nov 18, 2021 at 10:32:51PM -0800, Jay Dolan wrote: > > > > > > On 11/17/21 6:57 AM, Andy Shevchenko wrote: > > > > > > > Split Pericom driver to a separate module. > > > > > > > While at it, re-enable high baud rates. > > > > > > > > > > > > > > Jay, can you, please, test this on as many hardware as you have? > > > > > > > > > > ... > > > > > > > > > > > * Add in pericom_do_startup() because the UPF_MAGIC_MULTIPLIER doesn't > > > > > > stick. > > > > > > > > > > Can't find an evidence that this is the case. Can you recheck this (reading > > > > > flags back via sysfs or so)? So, for v2 I'll leave my approach. > > > > > > > > Otherwise how the other drivers which are using that flag survive? If it's > > > > indeed an issue, it should be fixed on generic level. > > > > > > > > > > I modified pericom_do_startup to log when the UPF_MAGIC_MULTIPLIER flag was > > > present. Then tried to set the port to 3000000 a few times. The port > > > stayed at 9600. It looks like pericom_do_startup() is getting called twice > > > per port on boot, and the flag is gone with the second one. > > > > > > [ 4.925577] [J4D] flag present > > > [ 4.926121] [J4D[ flag not present > > > [ 4.926843] [J4D] flag present > > > [ 4.927415] [J4D[ flag not present > > > [ 4.928106] [J4D] flag present > > > [ 4.928673] [J4D[ flag not present > > > [ 4.929419] [J4D] flag present > > > [ 4.930447] [J4D[ flag not present > > > > > > [ 49.528504] [J4D[ flag not present > > > [ 51.675240] [J4D[ flag not present > > > [ 59.617954] [J4D[ flag not present > > > > > > Then I modified it to log when it was adding the flag in. The port was set > > > to 3000000. Also the flag only needed to be added in once. It sticks after > > > the first time. > > > > > > [ 4.647546] [J4D] flag present > > > [ 4.648119] [J4D] flag not present(adding) > > > [ 4.648778] [J4D] flag present > > > [ 4.649330] [J4D] flag not present(adding) > > > [ 4.650001] [J4D] flag present > > > [ 4.650537] [J4D] flag not present(adding) > > > [ 4.651192] [J4D] flag present > > > [ 4.651718] [J4D] flag not present(adding) > > > > > > [ 96.025668] [J4D] flag present > > > [ 100.130626] [J4D] flag present > > > [ 116.435436] [J4D] flag present > > > > > > I mostly just guessed at do_startup() being the place to set the magic > > > multiplier flag after it didn't stick in quirk in 8250_pci.c. > > > > Can you share `dmesg` and output of `lspci -nk -vv` on the machine with the > > kernel with patches applied and running? > Provided below. Thanks! > Also, I am going to lose the place for my test station to > the family Christmas tree after tomorrow. I'm not sure when or where I'm > going to get it set back up. Understood, in case you still have time to test one idea below. As far as I understand current state of affairs the problematic part is the magic multiplier. > 01:00.0 0700: 494f:10dc (prog-if 02 [16550]) > Subsystem: 0001:0001 > Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- > Stepping- SERR- FastB2B- DisINTx- > Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- SERR- Latency: 0, Cache Line Size: 64 bytes > Interrupt: pin A routed to IRQ 16 > Region 0: I/O ports at e000 [size=64] > Region 1: Memory at fe400000 (32-bit, non-prefetchable) [size=4K] Okay, we are interested so far in IO bar (which is BAR0). Do you know what is the BAR1 for? > Capabilities: [80] 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: [8c] MSI: Enable- Count=1/1 Maskable- 64bit+ > Address: 0000000000000000 Data: 0000 > Capabilities: [9c] Vital Product Data > Not readable > Capabilities: [a4] Vendor Specific Information: Len=28 > Capabilities: [e0] Express (v1) Legacy Endpoint, MSI 00 > DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <64ns, L1 <1us > ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset- > DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported- > RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop- > MaxPayload 128 bytes, MaxReadReq 128 bytes > DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+ TransPend- > LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s > <512ns, L1 <1us > ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp- > LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk- > ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt- > LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk- DLActive- BWMgmt- > ABWMgmt- > Capabilities: [100 v1] 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- > Kernel driver in use: 8250_pericom > Kernel modules: 8250_pci, 8250_pericom Yep, two drivers matches and only 8250_pericom is in use. All good here. > [ 0.062531] pci 0000:01:00.0: [494f:10dc] type 00 class 0x070002 > [ 0.062551] pci 0000:01:00.0: reg 0x10: [io 0xe000-0xe03f] > [ 0.062562] pci 0000:01:00.0: reg 0x14: [mem 0xfe400000-0xfe400fff] > [ 0.062670] pci 0000:01:00.0: supports D1 D2 > [ 0.062673] pci 0000:01:00.0: PME# supported from D3hot Yeah, this interesting layout with 64 bytes and gap in UARTs 3-6. > [ 2.927496] Serial: 8250/16550 driver, 32 ports, IRQ sharing enabled > [ 2.927703] 00:04: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a > 16550A > [ 2.979481] 0000:01:00.0: ttyS4 at I/O 0xe000 (irq = 16, base_baud = > 921600) is a 16550A > [ 2.979487] 0000:01:00.0: ttyS4 extra baud rates supported: 1843200, > 3686400 > [ 2.979822] 0000:01:00.0: ttyS5 at I/O 0xe008 (irq = 16, base_baud = > 921600) is a 16550A > [ 2.979825] 0000:01:00.0: ttyS5 extra baud rates supported: 1843200, > 3686400 > [ 2.982020] 0000:01:00.0: ttyS6 at I/O 0xe010 (irq = 16, base_baud = > 921600) is a 16550A > [ 2.982025] 0000:01:00.0: ttyS6 extra baud rates supported: 1843200, > 3686400 > [ 2.982256] 0000:01:00.0: ttyS7 at I/O 0xe038 (irq = 16, base_baud = > 921600) is a 16550A > [ 2.982259] 0000:01:00.0: ttyS7 extra baud rates supported: 1843200, > 3686400 This is most important part. The code autodetects 16550A. Now I'm wondering if the following change will keep MAGIC multiplier untouched (instead of current patch): - uart.port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF | UPF_SHARE_IRQ; + uart.port.flags = UPF_FIXED_PORT | UPF_FIXED_TYPE | UPF_SHARE_IRQ | UPF_MAGIC_MULTIPLIER; + uart.port.type = PORT_16550A; > [ 42.730050] 8250_pericom 0000:01:00.0: VPD access failed. This is likely > a firmware bug on this device. Contact the card vendor for a firmware > update Not sure what is this and how it may affect anything. -- With Best Regards, Andy Shevchenko