From patchwork Mon Jul 25 16:39:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeremy Linton X-Patchwork-Id: 12928276 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 10FF3C43334 for ; Mon, 25 Jul 2022 16:40:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=17+1rgv8+6HJ6njGzvPwnLG64EQigvKgnB9Aal+m6Fg=; b=OiBaEn7XQ7QIPe gzm/kLFlD9MRL/jze1ee6lP6J6Jvxs6CFFvq4kOcayuro5XAd1s2Lm63aGiWDmf0eRLnSviDxS34H 0sGg2N4Z2QXk8Ll538hIvrNgLDZVkbB0Ot+kezrUkuBlBJbG8rqsZ6RbMPC7W/J0DtDdFIYJ9Imzt 0Qg06x8MboxfY7pyqBH1I0D06dO99KUyQNC7TUPdSwxo4xJe7wA56HYJ6gGROw+gy1kVrRn2sX/cJ zAjn4+I0IJ7elkZ58FxgrUkBGRv+5YD6oVw7z5GkGH7BgyChe5v7e7AcQbGtJdr++q1On3WHc1KMc PgbnDlmFmfW1CTcL7trw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oG17G-00FiBt-Vc; Mon, 25 Jul 2022 16:39:35 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oG16x-00Fi2j-5J for linux-arm-kernel@lists.infradead.org; Mon, 25 Jul 2022 16:39:18 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2CD1D152B; Mon, 25 Jul 2022 09:39:15 -0700 (PDT) Received: from mammon-tx2.austin.arm.com (mammon-tx2.austin.arm.com [10.118.28.62]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 63D843F73D; Mon, 25 Jul 2022 09:39:14 -0700 (PDT) From: Jeremy Linton To: linux-pci@vger.kernel.org Cc: will@kernel.org, bhelgaas@google.com, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, lpieralisi@kernel.org, kw@linux.com, mark.rutland@arm.com, sudeep.holla@arm.com, boqun.feng@gmail.com, catalin.marinas@arm.com, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Jeremy Linton Subject: [PATCH 3/4] PCI: host-generic: Add firmware managed config ops Date: Mon, 25 Jul 2022 11:39:04 -0500 Message-Id: <20220725163905.2024437-4-jeremy.linton@arm.com> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20220725163905.2024437-1-jeremy.linton@arm.com> References: <20220725163905.2024437-1-jeremy.linton@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220725_093915_330268_30C40BD5 X-CRM114-Status: GOOD ( 17.94 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The generic PCI host driver leaves the configuration and mgmt of the clock/phy/etc on PCI root ports to the firmware and PCIe defined mechanisms as is done on UEFI/ACPI systems. If the PCIe config operations were abstracted as well then a number of the resulting Linux PCie drivers would no longer be needed. Given that Arm has standardized a generic SMC conduit for reading and writing the PCIe config space. Using it on DT based systems seems a natural way to reduce some of the driver diversity on DT based systems as well. This patch adds a compatible type "pci-host-smc-generic" which expects that the 'reg' property of the root port is missing, and the PCI SMCCC exists. When that happens it binds the SMC to the pci_ecam_ops. Signed-off-by: Jeremy Linton --- drivers/pci/controller/pci-host-common.c | 34 ++++++++++++++++------- drivers/pci/controller/pci-host-generic.c | 6 ++++ 2 files changed, 30 insertions(+), 10 deletions(-) diff --git a/drivers/pci/controller/pci-host-common.c b/drivers/pci/controller/pci-host-common.c index d3924a44db02..2673fd81d3e0 100644 --- a/drivers/pci/controller/pci-host-common.c +++ b/drivers/pci/controller/pci-host-common.c @@ -20,22 +20,41 @@ static void gen_pci_unmap_cfg(void *ptr) pci_ecam_free((struct pci_config_window *)ptr); } +__weak int pcie_has_fw_conduit(void) +{ + return -EOPNOTSUPP; +} + +__weak struct pci_config_window *pci_setup_fw_mapping(struct device *dev, + u16 seg, struct resource *bus_res) +{ + return NULL; +} + static struct pci_config_window *gen_pci_init(struct device *dev, - struct pci_host_bridge *bridge, const struct pci_ecam_ops *ops) + struct pci_host_bridge *bridge) { int err; struct resource cfgres; struct resource_entry *bus; struct pci_config_window *cfg; + const struct pci_ecam_ops *ops; + + bus = resource_list_first_type(&bridge->windows, IORESOURCE_BUS); + if (!bus) + return ERR_PTR(-ENODEV); err = of_address_to_resource(dev->of_node, 0, &cfgres); if (err) { + if (!pcie_has_fw_conduit()) + return pci_setup_fw_mapping(dev, bridge->busnr, bus->res); + dev_err(dev, "missing \"reg\" property\n"); return ERR_PTR(err); } - bus = resource_list_first_type(&bridge->windows, IORESOURCE_BUS); - if (!bus) + ops = of_device_get_match_data(dev); + if (!ops) return ERR_PTR(-ENODEV); cfg = pci_ecam_create(dev, &cfgres, bus->res, ops); @@ -54,11 +73,6 @@ int pci_host_common_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; struct pci_host_bridge *bridge; struct pci_config_window *cfg; - const struct pci_ecam_ops *ops; - - ops = of_device_get_match_data(&pdev->dev); - if (!ops) - return -ENODEV; bridge = devm_pci_alloc_host_bridge(dev, 0); if (!bridge) @@ -69,7 +83,7 @@ int pci_host_common_probe(struct platform_device *pdev) of_pci_check_probe_only(); /* Parse and map our Configuration Space windows */ - cfg = gen_pci_init(dev, bridge, ops); + cfg = gen_pci_init(dev, bridge); if (IS_ERR(cfg)) return PTR_ERR(cfg); @@ -78,7 +92,7 @@ int pci_host_common_probe(struct platform_device *pdev) pci_add_flags(PCI_REASSIGN_ALL_BUS); bridge->sysdata = cfg; - bridge->ops = (struct pci_ops *)&ops->pci_ops; + bridge->ops = (struct pci_ops *)&cfg->ops->pci_ops; bridge->msi_domain = true; return pci_host_probe(bridge); diff --git a/drivers/pci/controller/pci-host-generic.c b/drivers/pci/controller/pci-host-generic.c index 63865aeb636b..d20d33b3c689 100644 --- a/drivers/pci/controller/pci-host-generic.c +++ b/drivers/pci/controller/pci-host-generic.c @@ -56,6 +56,9 @@ static const struct pci_ecam_ops pci_dw_ecam_bus_ops = { } }; +static const struct pci_ecam_ops pci_generic_smc_ops = { +}; + static const struct of_device_id gen_pci_of_match[] = { { .compatible = "pci-host-cam-generic", .data = &gen_pci_cfg_cam_bus_ops }, @@ -63,6 +66,9 @@ static const struct of_device_id gen_pci_of_match[] = { { .compatible = "pci-host-ecam-generic", .data = &pci_generic_ecam_ops }, + { .compatible = "pci-host-smc-generic", + .data = &pci_generic_smc_ops }, + { .compatible = "marvell,armada8k-pcie-ecam", .data = &pci_dw_ecam_bus_ops },