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{ "id": 2197394, "url": "http://patchwork.ozlabs.org/api/covers/2197394/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pci/cover/20260217212707.2450423-11-cassel@kernel.org/", "project": { "id": 28, "url": "http://patchwork.ozlabs.org/api/projects/28/?format=api", "name": "Linux PCI development", "link_name": "linux-pci", "list_id": "linux-pci.vger.kernel.org", "list_email": "linux-pci@vger.kernel.org", "web_url": null, "scm_url": null, "webscm_url": null, "list_archive_url": "", "list_archive_url_format": "", "commit_url_format": "" }, "msgid": "<20260217212707.2450423-11-cassel@kernel.org>", "list_archive_url": null, "date": "2026-02-17T21:27:06", "name": "[0/9] PCI: endpoint differentiate between disabled and reserved BARs", "submitter": { "id": 87751, "url": "http://patchwork.ozlabs.org/api/people/87751/?format=api", "name": "Niklas Cassel", "email": "cassel@kernel.org" }, "mbox": "http://patchwork.ozlabs.org/project/linux-pci/cover/20260217212707.2450423-11-cassel@kernel.org/mbox/", "series": [ { "id": 492482, "url": "http://patchwork.ozlabs.org/api/series/492482/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pci/list/?series=492482", "date": "2026-02-17T21:27:06", "name": "PCI: endpoint differentiate between disabled and reserved BARs", "version": 1, "mbox": "http://patchwork.ozlabs.org/series/492482/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/covers/2197394/comments/", "headers": { "Return-Path": "\n <linux-pci+bounces-47507-incoming=patchwork.ozlabs.org@vger.kernel.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "linux-pci@vger.kernel.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=HZ+UvMiP;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=172.234.253.10; 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a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1771363660; cv=none;\n b=mQPTpkrlOSZi2zuVGFa8PcDCLUSYtv9aDitTCAPuCqb1CRKlOexhCgrZDK1bFSbLzssSaw7apvwhatIUwnIorZpSDn7qRbBowABC0X+RXUOJINu4es3lH+tEsFDtQluKPOZe+xxYh86rUDQ/O3g+WcjU2snVapZeJ6gSfU0NBFA=", "ARC-Message-Signature": "i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1771363660; c=relaxed/simple;\n\tbh=qNdMPHb96ahPcc/FeBg2GRFGtCGsjvYyDufUCB6E5Ho=;\n\th=From:To:Cc:Subject:Date:Message-ID:MIME-Version;\n b=mUlmMdEoq5LZf8EtJS16x30JIQyljvqDeFFX4I/I8OjpeNQJWLHdurtuVo7t5zD/6qe4T8mRRKVW6Ncp61+J5ptMs2hl9AROASv8KBVnhQe5p+w36BbZQh6/VVNi61NQMW0rGr78X7qAU4KrCr4ANgt7soTLOCUKH94ZFvXTbRI=", "ARC-Authentication-Results": "i=1; smtp.subspace.kernel.org;\n dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org\n header.b=HZ+UvMiP; arc=none smtp.client-ip=10.30.226.201", "DKIM-Signature": "v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org;\n\ts=k20201202; t=1771363659;\n\tbh=qNdMPHb96ahPcc/FeBg2GRFGtCGsjvYyDufUCB6E5Ho=;\n\th=From:To:Cc:Subject:Date:From;\n\tb=HZ+UvMiPz7y6Wfbsg5SRIDmn+CDWDBq3WDUKPIFYPfrmgDfHjQ7tHHZYvBxWMJPsB\n\t c/PD0XktfttvuKxs+WJlENDTRUP8uJUYdvpCSgzgXvAFzPfb1B0rOK7s3NAuWfL7OM\n\t PDp3ZyEtU/CFNB0WzAkeTuWX12cuXeEN250jg2mphb4+0a1UOP9URjezN/AWag41Q0\n\t roA2SWQuJbNqVoB7NWp23sapC1Dm1S393B1Qqcg98UxhXC9rBuSiwP8ArfAEkppYLo\n\t 6sj4h5uEjhL1y9XxP5IphJD17zDcGD3gK+k+4gZR6DYzXHK6BRPDR/D2adYfFq7DLA\n\t JcoQPGf6g5NxA==", "From": "Niklas Cassel <cassel@kernel.org>", "To": "Manivannan Sadhasivam <mani@kernel.org>, =?utf-8?q?Krzysztof_Wilczy?=\n\t=?utf-8?q?=C5=84ski?= <kwilczynski@kernel.org>,\n Kishon Vijay Abraham I <kishon@kernel.org>, Arnd Bergmann <arnd@arndb.de>,\n Greg Kroah-Hartman <gregkh@linuxfoundation.org>,\n Vignesh Raghavendra <vigneshr@ti.com>,\n Siddharth Vadapalli <s-vadapalli@ti.com>,\n Lorenzo Pieralisi <lpieralisi@kernel.org>, Rob Herring <robh@kernel.org>,\n Bjorn Helgaas <bhelgaas@google.com>, Richard Zhu <hongxing.zhu@nxp.com>,\n Lucas Stach <l.stach@pengutronix.de>, Frank Li <Frank.Li@nxp.com>,\n Sascha Hauer <s.hauer@pengutronix.de>,\n Pengutronix Kernel Team <kernel@pengutronix.de>,\n Fabio Estevam <festevam@gmail.com>, Minghuan Lian <minghuan.Lian@nxp.com>,\n Mingkai Hu <mingkai.hu@nxp.com>, Roy Zang <roy.zang@nxp.com>,\n Jesper Nilsson <jesper.nilsson@axis.com>, Jingoo Han <jingoohan1@gmail.com>,\n Heiko Stuebner <heiko@sntech.de>,\n Srikanth Thokala <srikanth.thokala@intel.com>,\n Marek Vasut <marek.vasut+renesas@gmail.com>,\n Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,\n Geert Uytterhoeven <geert+renesas@glider.be>,\n Magnus Damm <magnus.damm@gmail.com>,\n Christian Bruel <christian.bruel@foss.st.com>,\n Maxime Coquelin <mcoquelin.stm32@gmail.com>,\n Alexandre Torgue <alexandre.torgue@foss.st.com>,\n Thierry Reding <thierry.reding@gmail.com>,\n Jonathan Hunter <jonathanh@nvidia.com>,\n Kunihiko Hayashi <hayashi.kunihiko@socionext.com>,\n Masami Hiramatsu <mhiramat@kernel.org>, Shuah Khan <shuah@kernel.org>", "Cc": "Manikanta Maddireddy <mmaddireddy@nvidia.com>,\n\tKoichiro Den <den@valinux.co.jp>,\n\tDamien Le Moal <dlemoal@kernel.org>,\n\tNiklas Cassel <cassel@kernel.org>,\n\tlinux-pci@vger.kernel.org,\n\tlinux-omap@vger.kernel.org,\n\tlinux-arm-kernel@lists.infradead.org,\n\timx@lists.linux.dev,\n\tlinuxppc-dev@lists.ozlabs.org,\n\tlinux-arm-kernel@axis.com,\n\tlinux-rockchip@lists.infradead.org,\n\tlinux-arm-msm@vger.kernel.org,\n\tlinux-renesas-soc@vger.kernel.org,\n\tlinux-stm32@st-md-mailman.stormreply.com,\n\tlinux-tegra@vger.kernel.org,\n\tlinux-kselftest@vger.kernel.org", "Subject": "[PATCH 0/9] PCI: endpoint differentiate between disabled and reserved\n BARs", "Date": "Tue, 17 Feb 2026 22:27:06 +0100", "Message-ID": "<20260217212707.2450423-11-cassel@kernel.org>", "X-Mailer": "git-send-email 2.53.0", "Precedence": "bulk", "X-Mailing-List": "linux-pci@vger.kernel.org", "List-Id": "<linux-pci.vger.kernel.org>", "List-Subscribe": "<mailto:linux-pci+subscribe@vger.kernel.org>", "List-Unsubscribe": "<mailto:linux-pci+unsubscribe@vger.kernel.org>", "MIME-Version": "1.0", "X-Developer-Signature": "v=1; a=openpgp-sha256; l=4061; i=cassel@kernel.org;\n h=from:subject; bh=qNdMPHb96ahPcc/FeBg2GRFGtCGsjvYyDufUCB6E5Ho=;\n b=owGbwMvMwCV2MsVw8cxjvkWMp9WSGDKn3NV+yyX95M1+T1HDqxGLE9Ks+cRk7p+2exh8+ZCxj\n pjCijkGHaUsDGJcDLJiiiy+P1z2F3e7TzmueMcGZg4rE8gQBi5OAZhI+E5GhguPHi2/Xb/y3DHB\n AIf6hAuN+VPmNN0usdy7vDq+avG27bYM/5S3MBlKbLy8vGB/jfcrobctfIebJrjrnqw9slP/atc\n TAw4A", "X-Developer-Key": "i=cassel@kernel.org; a=openpgp;\n fpr=5ADE635C0E631CBBD5BE065A352FE6582ED9B5DA", "Content-Transfer-Encoding": "8bit" }, "content": "Hello all,\n\nThis series is written in response to the patch series from\nManikanta Maddireddy that was posted here:\nhttps://lore.kernel.org/linux-pci/291dab65-3fa6-4fc8-90a2-4ad608ca015c@nvidia.com/T/#t\n\nThe reasons why I decided to post this a new series was because the series\nabove:\n\n1) Adds PCI device and vendor specific code to\ndrivers/misc/pci_endpoint_test.c. We've worked hard to make sure that\ndevice specific quirks/limitations are communicated via the Capabilities\nregister, so let's do the same for reserved BARs.\n\n2) My review comment which suggested to convert all uses of BAR_RESERVED\nto BAR_DISABLED (except for pci-keystone.c) was ignored.\n\n3) Koichiro has posted a series that allows an EPC driver to define exactly\nwhich hardware backed resources are provided in a BAR_RESERVED BAR. Yet,\nthis nice improvement was not incorporated. (While Mankata was part of the\ndiscussion, he was not CC:d on the patches that actually implemented this.)\n\n4) The selftests should return skip instead of silent success for a\nreserved BAR.\n\n5) As Mankata points out, but did not address, BAR_RESERVED is quite\nambiguous, so it is better to introduce a new BAR_64BIT_UPPER to more\nclearly mark the upper part of a 64-bit BAR as this, rather than reuse\nBAR_RESERVED.\n\n6) It is possible to remove all the dw_pcie_ep_reset_bar() calls in the\nDWC based glue drivers and move it to DWC common code.\n\n\nBecause of all of the above, I thought it was just easier to post a series\nwith all of the above addressed, as it seemed easier to just show what I\nmeant rather than to try to explain things with words.\n\nThe thing that is missing is to add a patch for pcie-tegra194.c which\nconverts the BARs to BAR_RESERVED.\nPlease see patch \"PCI: dw-rockchip: Describe RK3588 BAR4 DMA ctrl window\"\nand do something similar to pcie-tegra194.c.\n\nIf we are missing some resources (right now we only have\nPCI_EPC_BAR_RSVD_DMA_CTRL_MMIO), then I think we should simple add that\n(e.g. PCI_EPC_BAR_RSVD_MSIX).\n\nMankata, it would be nice if you could test this series, and if you could\nprovide a pcie-tegra194.c patch that adds the sizes of the eDMA regs +\nMSI-X table in BAR_2 and BAR_4.\n\n\nKind regards,\nNiklas\n\n\nKoichiro Den (2):\n PCI: endpoint: Describe reserved subregions within BARs\n PCI: dw-rockchip: Describe RK3588 BAR4 DMA ctrl window\n\nNiklas Cassel (7):\n PCI: endpoint: Introduce pci_epc_bar_type BAR_64BIT_UPPER\n PCI: endpoint: Introduce pci_epc_bar_type BAR_DISABLED\n PCI: dwc: Replace BAR_RESERVED with BAR_DISABLED in glue drivers\n PCI: dwc: Disable BARs in common code instead of in each glue driver\n PCI: endpoint: pci-epf-test: Advertise reserved BARs\n misc: pci_endpoint_test: Give reserved BARs a distinct error code\n selftests: pci_endpoint: Skip reserved BARs\n\n drivers/misc/pci_endpoint_test.c | 32 ++++++++++++-\n drivers/pci/controller/dwc/pci-dra7xx.c | 4 --\n drivers/pci/controller/dwc/pci-imx6.c | 22 +++------\n .../pci/controller/dwc/pci-layerscape-ep.c | 8 +---\n drivers/pci/controller/dwc/pcie-artpec6.c | 4 --\n .../pci/controller/dwc/pcie-designware-ep.c | 24 ++++++++++\n .../pci/controller/dwc/pcie-designware-plat.c | 10 -----\n drivers/pci/controller/dwc/pcie-dw-rockchip.c | 19 +++++---\n drivers/pci/controller/dwc/pcie-keembay.c | 6 +--\n drivers/pci/controller/dwc/pcie-qcom-ep.c | 14 +-----\n drivers/pci/controller/dwc/pcie-rcar-gen4.c | 16 ++-----\n drivers/pci/controller/dwc/pcie-stm32-ep.c | 10 -----\n drivers/pci/controller/dwc/pcie-tegra194.c | 20 +++------\n drivers/pci/controller/dwc/pcie-uniphier-ep.c | 24 +++-------\n drivers/pci/controller/pcie-rcar-ep.c | 6 +--\n drivers/pci/endpoint/functions/pci-epf-test.c | 24 ++++++++++\n drivers/pci/endpoint/pci-epc-core.c | 6 ++-\n include/linux/pci-epc.h | 45 +++++++++++++++++--\n .../pci_endpoint/pci_endpoint_test.c | 4 ++\n 19 files changed, 173 insertions(+), 125 deletions(-)" }