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 D51A5C433F5 for ; Tue, 17 May 2022 17:21:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343775AbiEQRVJ (ORCPT ); Tue, 17 May 2022 13:21:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47930 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351408AbiEQRU5 (ORCPT ); Tue, 17 May 2022 13:20:57 -0400 Received: from mail-pl1-x629.google.com (mail-pl1-x629.google.com [IPv6:2607:f8b0:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E25C6B48B for ; Tue, 17 May 2022 10:20:51 -0700 (PDT) Received: by mail-pl1-x629.google.com with SMTP id i1so17935166plg.7 for ; Tue, 17 May 2022 10:20:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=qqJFZR8hTHMEpR03D7fICklADGJ1sACe7dmVDrtTPPA=; b=ysKA7bOi5+9RdlYYFAsM9Hnm1Y0faip7O/uZx4Jtrfz0r6k4k9vYUggKvc5yQ1exMX 0Pwj7rSiWyjhXnLuAa1fGnu86owf5xZB9vxKXt7HfttlGj2yZzMka+qecyCOX9uSp5cY UqTpAmywLrPUduIU5lo9vkJltg04KLwc8vGzsN4HDy2Jnt5RmvGUqK7ghg+RU4exZ6vV utDNHvGDt6AEwWhhCSMvNpL88PIS7CnKCStA4CTurHtGE66zyvTeVATQ/VFDPEqYO0Ey 7jxg4aj0txKQirK+i5UXExqVypOCrnjFbiHxI/V18PcD3EcvzB9R2TEgawxCCzAaKEnG 43qw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=qqJFZR8hTHMEpR03D7fICklADGJ1sACe7dmVDrtTPPA=; b=z0ARqmsLBv8biZdCkOv7SjvZ2waMXSvuVDrDjt3FyXW8cJjp0LFqB4NVH2toDwL7Sy JNQLIsISDBMkhrebvcPKP8U53et7w3eSGHcMFFaQUDhzVTa6glkYuXb/2blGlbGH5mMo 7yc79Vb7WnoDesXR+2Q0nxDlHZLrPzXmk1++ImybZ9FAgbb1WmcnQbzr3LL/1uw/7luz 990eNAwsqL5P9qdAiVEw/wlY22bhHJ5K6hH02xaOUmVDl63tTBp0XX0pRu9+wujTFxO9 HYMJzvAkiu7/k1oq4pp3+EawOGhwcZammim43Pn5VTB1OuuwKtRWv4rXV+OOeC8ql2mX dP5Q== X-Gm-Message-State: AOAM533Hn1/GR4ftOFgDoQ1w94nsAHCcF5pV+UVOEWvACIfmnZzGjCtu jChXT3i8TLyW8GRnfS1kQWwZ X-Google-Smtp-Source: ABdhPJyhG3jIHWQ/4DWEUJffCPPujUE5uN8SWJy3rwsGgWf/e3ngmDrUje9ryR1pgmwqMjvcBEexhg== X-Received: by 2002:a17:90a:8b91:b0:1be:db25:eecd with SMTP id z17-20020a17090a8b9100b001bedb25eecdmr25779420pjn.10.1652808051232; Tue, 17 May 2022 10:20:51 -0700 (PDT) Received: from thinkpad ([117.207.31.8]) by smtp.gmail.com with ESMTPSA id i7-20020a63cd07000000b003c14af5063esm8882115pgg.86.2022.05.17.10.20.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 May 2022 10:20:50 -0700 (PDT) Date: Tue, 17 May 2022 22:50:42 +0530 From: Manivannan Sadhasivam To: Serge Semin Cc: Serge Semin , Jingoo Han , Gustavo Pimentel , Bjorn Helgaas , Lorenzo Pieralisi , Rob Herring , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Alexey Malahov , Pavel Parkhomenko , Frank Li , Rob Herring , linux-pci@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 15/17] PCI: dwc: Introduce dma-ranges property support for RC-host Message-ID: <20220517172042.GC4528@thinkpad> References: <20220503214638.1895-1-Sergey.Semin@baikalelectronics.ru> <20220503214638.1895-16-Sergey.Semin@baikalelectronics.ru> <20220512135708.GC35848@thinkpad> <20220512194135.ku73pae2xdvyocx7@mobilestation> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20220512194135.ku73pae2xdvyocx7@mobilestation> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Thu, May 12, 2022 at 10:41:35PM +0300, Serge Semin wrote: > On Thu, May 12, 2022 at 07:27:08PM +0530, Manivannan Sadhasivam wrote: > > On Wed, May 04, 2022 at 12:46:36AM +0300, Serge Semin wrote: > > > In accordance with the generic PCIe Root Port DT-bindings the "dma-ranges" > > > property has the same format as the "ranges" property. The only difference > > > is in their semantics. The "dma-ranges" property describes the PCIe-to-CPU > > > memory mapping in opposite to the CPU-to-PCIe mapping of the "ranges" > > > property. Even though the DW PCIe controllers are normally equipped with > > > internal Address Translation Unit which inbound and outbound tables can be > > > used to implement both properties semantics, it was surprise for me to > > > discover that the host-related part of the DW PCIe driver currently > > > supports the "ranges" property only while the "dma-ranges" windows are > > > just ignored. Having the "dma-ranges" supported in the driver would be > > > very handy for the platforms, that don't tolerate the 1:1 CPU-PCIe memory > > > mapping and require customized the PCIe memory layout. So let's fix that > > > by introducing the "dma-ranges" property support. > > > > > > First of all we suggest to rename the dw_pcie_prog_inbound_atu() method to > > > dw_pcie_prog_ep_inbound_atu() and create a new version of the > > > dw_pcie_prog_inbound_atu() function. Thus we'll have two methods for RC > > > and EP controllers respectively in the same way as it has been developed > > > for the outbound ATU setup methods. > > > > > > Secondly aside with the memory window index and type the new > > > dw_pcie_prog_inbound_atu() function will accept CPU address, PCIe address > > > and size as its arguments. These parameters define the PCIe and CPU memory > > > ranges which will be used to setup the respective inbound ATU mapping. The > > > passed parameters need to be verified against the ATU ranges constraints > > > in the same way as it is done for the outbound ranges. > > > > > > Finally the DMA-ranges detected for the PCIe controller need to be > > > converted into the inbound ATU entries during the host controller > > > initialization procedure. It will be done in the framework of the > > > dw_pcie_iatu_setup() method. Note before setting the inbound ranges up we > > > need to disable all the inbound ATU entries in order to prevent unexpected > > > PCIe TLPs translations defined by some third party software like > > > bootloader. > > > > > > Signed-off-by: Serge Semin > > > --- > > > .../pci/controller/dwc/pcie-designware-ep.c | 4 +- > > > .../pci/controller/dwc/pcie-designware-host.c | 32 ++++++++++- > > > drivers/pci/controller/dwc/pcie-designware.c | 57 ++++++++++++++++++- > > > drivers/pci/controller/dwc/pcie-designware.h | 6 +- > > > 4 files changed, 90 insertions(+), 9 deletions(-) > > > > > > diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c > > > index c62640201246..9b0540cfa9e8 100644 > > > --- a/drivers/pci/controller/dwc/pcie-designware-ep.c > > > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c > > > @@ -167,8 +167,8 @@ static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, u8 func_no, int type, > > > return -EINVAL; > > > } > > > > > > - ret = dw_pcie_prog_inbound_atu(pci, func_no, free_win, type, > > > - cpu_addr, bar); > > > + ret = dw_pcie_prog_ep_inbound_atu(pci, func_no, free_win, type, > > > + cpu_addr, bar); > > > if (ret < 0) { > > > dev_err(pci->dev, "Failed to program IB window\n"); > > > return ret; > > > diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c > > > index 7caca6c575a5..9cb406f5c185 100644 > > > --- a/drivers/pci/controller/dwc/pcie-designware-host.c > > > +++ b/drivers/pci/controller/dwc/pcie-designware-host.c > > > @@ -612,12 +612,15 @@ static int dw_pcie_iatu_setup(struct pcie_port *pp) > > > } > > > > > > /* > > > - * Ensure all outbound windows are disabled before proceeding with > > > - * the MEM/IO ranges setups. > > > + * Ensure all out/inbound windows are disabled before proceeding with > > > + * the MEM/IO (dma-)ranges setups. > > > */ > > > for (i = 0; i < pci->num_ob_windows; i++) > > > dw_pcie_disable_atu(pci, PCIE_ATU_REGION_DIR_OB, i); > > > > > > + for (i = 0; i < pci->num_ib_windows; i++) > > > + dw_pcie_disable_atu(pci, PCIE_ATU_REGION_DIR_IB, i); > > > + > > > i = 0; > > > resource_list_for_each_entry(entry, &pp->bridge->windows) { > > > if (resource_type(entry->res) != IORESOURCE_MEM) > > > @@ -654,9 +657,32 @@ static int dw_pcie_iatu_setup(struct pcie_port *pp) > > > } > > > > > > if (pci->num_ob_windows <= i) > > > - dev_warn(pci->dev, "Resources exceed number of ATU entries (%d)\n", > > > + dev_warn(pci->dev, "Ranges exceed outbound iATU size (%d)\n", > > > pci->num_ob_windows); > > > > > > + i = 0; > > > + resource_list_for_each_entry(entry, &pp->bridge->dma_ranges) { > > > + if (resource_type(entry->res) != IORESOURCE_MEM) > > > + continue; > > > + > > > + if (pci->num_ib_windows <= i) > > > + break; > > > + > > > + ret = dw_pcie_prog_inbound_atu(pci, i++, PCIE_ATU_TYPE_MEM, > > > + entry->res->start, > > > + entry->res->start - entry->offset, > > > + resource_size(entry->res)); > > > + if (ret) { > > > + dev_err(pci->dev, "Failed to set DMA range %pr\n", > > > + entry->res); > > > + return ret; > > > + } > > > + } > > > + > > > + if (pci->num_ib_windows <= i) > > > + dev_warn(pci->dev, "Dma-ranges exceed inbound iATU size (%u)\n", > > > + pci->num_ib_windows); > > > + > > > return 0; > > > } > > > > > > diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c > > > index 747e252c09e6..33718ed6c511 100644 > > > --- a/drivers/pci/controller/dwc/pcie-designware.c > > > +++ b/drivers/pci/controller/dwc/pcie-designware.c > > > @@ -397,8 +397,61 @@ static inline void dw_pcie_writel_atu_ib(struct dw_pcie *pci, u32 index, u32 reg > > > dw_pcie_writel_atu(pci, PCIE_ATU_REGION_DIR_IB, index, reg, val); > > > } > > > > > > -int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, u8 func_no, int index, > > > - int type, u64 cpu_addr, u8 bar) > > > +int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, int index, int type, > > > + u64 cpu_addr, u64 pci_addr, u64 size) > > > +{ > > > + u64 limit_addr = pci_addr + size - 1; > > > + u32 retries, val; > > > + > > > + if ((limit_addr & ~pci->region_limit) != (pci_addr & ~pci->region_limit) || > > > + !IS_ALIGNED(cpu_addr, pci->region_align) || > > > + !IS_ALIGNED(pci_addr, pci->region_align) || > > > + !IS_ALIGNED(size, pci->region_align) || > > > > > Why do you want the size to be aligned? What if I want to transfer a small size > > buffer? > > > > Same question applies to outbound programming as well. > > You can't program a region with the unaligned size by the DW PCIe CSRs > design. The limit address lower bits are read-only and fixed with > one's in accordance with the IP-core synthesize parameter > CX_ATU_MIN_REGION_SIZE. So the mapping is always performed in the > CX_ATU_MIN_REGION_SIZE chunks. > > IATU_LIMIT_ADDR_OFF_{IN,OUT}BOUND.LIMIT_ADDR_HW = > {(CX_ATU_MIN_REGION_SIZE == 65536) ? "0xffff" : > (CX_ATU_MIN_REGION_SIZE == 32768) ? "0x7fff" : > (CX_ATU_MIN_REGION_SIZE == 16384) ? "0x3fff" : > (CX_ATU_MIN_REGION_SIZE == 8192) ? "0x1fff" : > (CX_ATU_MIN_REGION_SIZE == 4096) ? "0xfff" : "0xffff"} > Right. Even though the minimum size that could be mapped is 4k, I could still use that 4k size for mapping small buffers also. So you should not be erroring out here if the size is not aligned. I know that it is a waste of memory but that doesn't mean that it won't work. Thanks, Mani > -Sergey > > > > > Thanks, > > Mani > > > > -- > > மணிவண்ணன் சதாசிவம் -- மணிவண்ணன் சதாசிவம்