From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-out.m-online.net ([212.18.0.10]:58698 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756199Ab3LEB7p (ORCPT ); Wed, 4 Dec 2013 20:59:45 -0500 From: Marek Vasut To: Richard Zhu Subject: Re: [PATCH 2/7] [RFC] PCI: imx6: remove outbound io/mem ATU region mapping Date: Thu, 5 Dec 2013 02:59:33 +0100 Cc: Jingoo Han , "'Tim Harvey'" , "'Pratyush Anand'" , "linux-arm-kernel@lists.infradead.org" , "linux-pci@vger.kernel.org" , "'Bjorn Helgaas'" , "'Frank Li'" , "'Harro Haan'" , "'Mohit KUMAR DCG'" , "'Sascha Hauer'" , "'Sean Cross'" , "'Shawn Guo'" , "'Siva Reddy Kallam'" , "'Srikanth T Shivanand'" , "'Troy Kisky'" , "'Yinghai Lu'" References: <1385500248-6551-1-git-send-email-marex@denx.de> <0E83723C55F66F43A6041464FE31119D47C9FA@039-SN2MPN1-013.039d.mgd.msft.net> <0E83723C55F66F43A6041464FE31119D47CA7F@039-SN2MPN1-013.039d.mgd.msft.net> In-Reply-To: <0E83723C55F66F43A6041464FE31119D47CA7F@039-SN2MPN1-013.039d.mgd.msft.net> MIME-Version: 1.0 Content-Type: Text/Plain; charset="us-ascii" Message-Id: <201312050259.33823.marex@denx.de> Sender: linux-pci-owner@vger.kernel.org List-ID: On Thursday, December 05, 2013 at 02:05:40 AM, Richard Zhu wrote: > Hi Merak: > > -----Original Message----- > > From: linux-pci-owner@vger.kernel.org > > [mailto:linux-pci-owner@vger.kernel.org] On Behalf Of Richard Zhu > > Sent: Thursday, December 05, 2013 8:45 AM > > To: Marek Vasut > > Cc: Jingoo Han; 'Tim Harvey'; 'Pratyush Anand'; linux-arm- > > kernel@lists.infradead.org; linux-pci@vger.kernel.org; 'Bjorn Helgaas'; > > 'Frank Li'; 'Harro Haan'; 'Mohit KUMAR DCG'; 'Sascha Hauer'; 'Sean > > Cross'; 'Shawn Guo'; 'Siva Reddy Kallam'; 'Srikanth T Shivanand'; 'Troy > > Kisky'; 'Yinghai Lu' Subject: RE: [PATCH 2/7] [RFC] PCI: imx6: remove > > outbound io/mem ATU region mapping > > > > Hi Marek: > > > -----Original Message----- > > > From: Marek Vasut [mailto:marex@denx.de] > > > Sent: Wednesday, December 04, 2013 3:52 PM > > > To: Zhu Richard-R65037 > > > Cc: Jingoo Han; 'Tim Harvey'; 'Pratyush Anand'; linux-arm- > > > kernel@lists.infradead.org; linux-pci@vger.kernel.org; 'Bjorn > > > Helgaas'; 'Frank Li'; 'Harro Haan'; 'Mohit KUMAR DCG'; 'Sascha Hauer'; > > > 'Sean Cross'; 'Shawn Guo'; 'Siva Reddy Kallam'; 'Srikanth T Shivanand'; > > > > 'Troy Kisky'; 'Yinghai Lu' > > > > > Subject: Re: [PATCH 2/7] [RFC] PCI: imx6: remove outbound io/mem ATU > > > region mapping > > > > > > On Wednesday, December 04, 2013 at 06:49:55 AM, Richard Zhu wrote: > > > > Hi Marek: > > > > > > > > Best Regards > > > > Richard Zhu > > > > > > > > > -----Original Message----- > > > > > From: Marek Vasut [mailto:marex@denx.de] > > > > > Sent: Friday, November 29, 2013 1:56 AM > > > > > To: Jingoo Han > > > > > Cc: 'Tim Harvey'; 'Pratyush Anand'; > > > > > linux-arm-kernel@lists.infradead.org; > > > > > linux-pci@vger.kernel.org; 'Bjorn Helgaas'; 'Frank Li'; 'Harro > > > > > Haan'; 'Mohit KUMAR DCG'; Zhu Richard-R65037; 'Sascha Hauer'; > > > > > 'Sean Cross'; 'Shawn Guo'; 'Siva Reddy Kallam'; 'Srikanth T > > > > > Shivanand'; 'Troy Kisky'; 'Yinghai Lu' Subject: Re: [PATCH 2/7] > > > > > [RFC] > > > > PCI: imx6: > > > > > remove outbound io/mem ATU region mapping > > > > > > > > > > Dear Jingoo Han, > > > > > > > > > > > On Wednesday, November 27, 2013 5:44 PM, Marek Vasut wrote: > > > > > > > Wednesday, November 27, 2013 1:30 PM, Pratyush Anand wrote: > > > > > > > > On Wed, Nov 27, 2013 at 05:10:43AM +0800, Marek Vasut wrote: > > > > > > > > > From: Tim Harvey > > > > > > > > > > > > > > > > > > The IMX6 iATU is used for address translation between the > > > > > > > > > AXI bus address space and PCI address space. This is used > > > > > > > > > for type0 and > > > > > > > > > type1 config cycles but is not necessary for outbound > > > > > > > > > io/mem regions. > > > > > > > > > > > > > > > > > > This patch removes the calls that inappropriately > > > > > > > > > re-configures the ATU viewport for outbound memory and IO > > > > > > > > > after config cycles and removes them altogether as they > > > > > > > > > are not > > > > > > necessary. > > > > > > > > > > > Yes, they are not necessary for all the cases where > > > > > > > > translation is one to one. So so for sure all the platform > > > > > > > > till now introduced should work. > > > > > > > > But, what about a platform where memory translation is not > > > > > > > > one to one? > > > > > > > > > > > > > > > > Existing code should work with all sort of memory > > > > > > > > translation on a platform having atleast two viewports > > > > > > > > capable of programming any type of outbound transaction. > > > > > > > > > > > > > > Full ACK, that's why it's called RFC. > > > > > > > > > > > > > > > > This resolves issues with PCI devices behind switches and > > > > > > > > > has been tested with a Gige device behind a PLX PEX860x > > > > > > > > > switch. More testing is needed for other configurations. > > > > > > > > > > > > > > > > I do not understand if MX6 has 4 Outbound Viewport then how > > > > > > > > this patch helps? > > > > > > > > -- PCI devices behind switches would not have been working > > > > > > > > because > > > > > > > > CFG1 transaction would not have been correct. > > > > > > > > -- It works with this patch. This patch changes viewport for > > > > > > > > CFG1 from > > > > > > > > 1 to 0. > > > > > > > > -- Can it be possible that MX6 has some restriction on > > > > > > > > viewport programming capability. I mean,like only viewport0 > > > > > > > > can be programmed for CFG0/1? > > > > > > > > > > > > > > Tim ? > > > > > > > > > > > > > > Here is the MX6 datasheet [1], the section 48.3.9.1.1 and > > > > > > > 48.3.9.1.2 describe the iATU configuration on MX6. My > > > > > > > understanding from this description is that the MX6 has 4 > > > > > > > inbound and 4 outbound iATU regions. Am I wrong ? > > > > > > > > > > > > The numbers of inbound and outbound are hardware-configurable > > > > > > features. Thus, these numbers can be confirmed by Freescale > > > > > > hardware engineers. How about asking Freescale hardware > > > > > > engineers, if possible? > > > > > > > > > > Richard is on the CC. Richard, can you please confirm those? > > > > > > > > [Richard] One Pericom PI7C9X2G303EL pcie switch, and two pcie ep > > > > deivces(one is intel e1000e nic, the other is one xhci device) are > > > > tested on imx6q sabresd board. Without removing outbound io/mem > > > > regions view map during the cfg0/1 read/write cycle, both of these > > > > devices can't work well at my side. Works well after remove them > > > > during the cfg0/1 read/write cycles. > > > > Same to Tim's situation about switch implementation. > > > > > > Thanks Richard! I am just wondering what kind of conclusion can we > > > draw from this. Let me reiterate what we have: > > > > > > - i.MX6 has 4 inbound and 4 outbound iATU regions, is that correct, > > > Richard? - If we program the iATU regions, the i.MX6 PCIe doesn't work > > > with switch. > > > > > > Is there some special sause to the iATU on MX6 maybe ? > > > > [Richard] welcome, it's correct, imx6 pcie has 4 inbount and 4 outbound > > iATU regions. > > Imx6 pcie doesn't work with switch if the following view switches are not > > removed in The cfg0/1 read/write cycles. > > > > @@ -516,9 +560,11 @@ static int dw_pcie_rd_other_conf(struct pcie_port > > *pp, struct pci_bus *bus, > > > > if (bus->parent->number == pp->root_bus_nr) { > > > > dw_pcie_prog_viewport_cfg0(pp, busdev); > > ret = cfg_read(pp->va_cfg0_base + address, where, size, > > val); > > > > + // dw_pcie_prog_viewport_mem_outbound(pp); > > > > } else { > > > > dw_pcie_prog_viewport_cfg1(pp, busdev); > > ret = cfg_read(pp->va_cfg1_base + address, where, size, > > val); > > > > + // dw_pcie_prog_viewport_io_outbound(pp); > > > > } > > > > return ret; > > > > @@ -537,9 +583,11 @@ static int dw_pcie_wr_other_conf(struct pcie_port > > *pp, struct pci_bus *bus, > > > > if (bus->parent->number == pp->root_bus_nr) { > > > > dw_pcie_prog_viewport_cfg0(pp, busdev); > > ret = cfg_write(pp->va_cfg0_base + address, where, size, > > val); > > > > + // dw_pcie_prog_viewport_mem_outbound(pp); > > > > } else { > > > > dw_pcie_prog_viewport_cfg1(pp, busdev); > > ret = cfg_write(pp->va_cfg1_base + address, where, size, > > val); > > > > + // dw_pcie_prog_viewport_io_outbound(pp); > > > > } > > > > return ret; > > > > Best Regards > > Richard Zhu > > [Richard] Bisect the code-modifications, only the > dw_pcie_prog_viewport_io_outbound() should be masked if I want the switch > works in my imx6 pcie switch support tests. Suspect that the mem emulated > io space introduce this problem, debug is on-going. Freescale is now looking into this issue ? Cool, thanks! :)