From patchwork Thu Mar 25 09:09:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kishon Vijay Abraham I X-Patchwork-Id: 12163523 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNWANTED_LANGUAGE_BODY,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6CFBC433C1 for ; Thu, 25 Mar 2021 09:11:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A83A061A23 for ; Thu, 25 Mar 2021 09:11:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229631AbhCYJKq (ORCPT ); Thu, 25 Mar 2021 05:10:46 -0400 Received: from fllv0015.ext.ti.com ([198.47.19.141]:40468 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229782AbhCYJKI (ORCPT ); Thu, 25 Mar 2021 05:10:08 -0400 Received: from fllv0035.itg.ti.com ([10.64.41.0]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 12P99qXE104779; Thu, 25 Mar 2021 04:09:52 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1616663392; bh=r0svPmuI2QaSe9vWLMxAjahbDeP9jzCVWUl33+1rTno=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=DcBuGUGVu7429fazwJXWf4qnOHebMgdw3KEkLoKeVFAxP2ElpbbeCVH1r1iO8ZV3D nvZW6auNgYKP7O1RTgtSHeEK2/02F9Jbnh4jLA3uM7DTgWbF40bRxSic3zQuwom6qE iilXV7ilq+aNywhC0GLJnBQGgbvw8MSqWcudoPds= Received: from DFLE100.ent.ti.com (dfle100.ent.ti.com [10.64.6.21]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 12P99qSO008018 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 25 Mar 2021 04:09:52 -0500 Received: from DFLE110.ent.ti.com (10.64.6.31) by DFLE100.ent.ti.com (10.64.6.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Thu, 25 Mar 2021 04:09:52 -0500 Received: from fllv0039.itg.ti.com (10.64.41.19) by DFLE110.ent.ti.com (10.64.6.31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2 via Frontend Transport; Thu, 25 Mar 2021 04:09:52 -0500 Received: from a0393678-ssd.dhcp.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id 12P99b9x078373; Thu, 25 Mar 2021 04:09:48 -0500 From: Kishon Vijay Abraham I To: Kishon Vijay Abraham I , Bjorn Helgaas , Rob Herring , Lorenzo Pieralisi , Marc Zyngier CC: Tom Joseph , , , , , , Lokesh Vutla Subject: [PATCH 2/4] PCI: j721e: Add PCI legacy interrupt support for J721E Date: Thu, 25 Mar 2021 14:39:34 +0530 Message-ID: <20210325090936.9306-3-kishon@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210325090936.9306-1-kishon@ti.com> References: <20210325090936.9306-1-kishon@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add PCI legacy interrupt support for J721E. J721E has a single HW interrupt line for all the four legacy interrupts INTA/INTB/INTC/INTD. The HW interrupt line connected to GIC is a pulse interrupt whereas the legacy interrupts by definition is level interrupt. In order to provide level interrupt functionality to edge interrupt line, PCIe in J721E has provided IRQ_EOI register. When the SW writes to IRQ_EOI register after handling the interrupt, the IP checks the state of legacy interrupt and re-triggers pulse interrupt invoking the handler again. Signed-off-by: Kishon Vijay Abraham I --- drivers/pci/controller/cadence/pci-j721e.c | 91 ++++++++++++++++++++++ 1 file changed, 91 insertions(+) diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c index 0382bb15c6f9..17db86a51ca8 100644 --- a/drivers/pci/controller/cadence/pci-j721e.c +++ b/drivers/pci/controller/cadence/pci-j721e.c @@ -28,6 +28,13 @@ #define STATUS_CLR_REG_SYS_2 0x708 #define LINK_DOWN BIT(1) +#define EOI_REG 0x10 + +#define ENABLE_REG_SYS_0 0x100 +#define STATUS_REG_SYS_0 0x500 +#define STATUS_CLR_REG_SYS_0 0x700 +#define INTx_EN(num) (1 << (num)) + #define J721E_PCIE_USER_CMD_STATUS 0x4 #define LINK_TRAINING_ENABLE BIT(0) @@ -57,6 +64,7 @@ struct j721e_pcie { struct cdns_pcie *cdns_pcie; void __iomem *user_cfg_base; void __iomem *intd_cfg_base; + struct irq_domain *legacy_irq_domain; }; enum j721e_pcie_mode { @@ -116,6 +124,85 @@ static void j721e_pcie_config_link_irq(struct j721e_pcie *pcie) j721e_pcie_intd_writel(pcie, ENABLE_REG_SYS_2, reg); } +static void j721e_pcie_legacy_irq_handler(struct irq_desc *desc) +{ + int i; + u32 reg; + int virq; + struct j721e_pcie *pcie = irq_desc_get_handler_data(desc); + struct irq_chip *chip = irq_desc_get_chip(desc); + + chained_irq_enter(chip, desc); + + for (i = 0; i < PCI_NUM_INTX; i++) { + reg = j721e_pcie_intd_readl(pcie, STATUS_REG_SYS_0); + if (!(reg & INTx_EN(i))) + continue; + + virq = irq_find_mapping(pcie->legacy_irq_domain, 3 - i); + generic_handle_irq(virq); + j721e_pcie_intd_writel(pcie, STATUS_CLR_REG_SYS_0, INTx_EN(i)); + j721e_pcie_intd_writel(pcie, EOI_REG, 3 - i); + } + + chained_irq_exit(chip, desc); +} + +static int j721e_pcie_intx_map(struct irq_domain *domain, unsigned int irq, + irq_hw_number_t hwirq) +{ + irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq); + irq_set_chip_data(irq, domain->host_data); + + return 0; +} + +static const struct irq_domain_ops j721e_pcie_intx_domain_ops = { + .map = j721e_pcie_intx_map, +}; + +static int j721e_pcie_config_legacy_irq(struct j721e_pcie *pcie) +{ + struct device *dev = pcie->dev; + struct irq_domain *legacy_irq_domain; + struct device_node *node = dev->of_node; + struct device_node *intc_node; + int irq; + u32 reg; + int i; + + intc_node = of_get_child_by_name(node, "interrupt-controller"); + if (!intc_node) { + dev_WARN(dev, "legacy-interrupt-controller node is absent\n"); + return -EINVAL; + } + + irq = irq_of_parse_and_map(intc_node, 0); + if (!irq) { + dev_err(dev, "Failed to parse and map legacy irq\n"); + return -EINVAL; + } + irq_set_chained_handler_and_data(irq, j721e_pcie_legacy_irq_handler, + pcie); + + legacy_irq_domain = irq_domain_add_linear(intc_node, PCI_NUM_INTX, + &j721e_pcie_intx_domain_ops, + NULL); + if (!legacy_irq_domain) { + dev_err(dev, "Failed to add irq domain for legacy irqs\n"); + return -EINVAL; + } + pcie->legacy_irq_domain = legacy_irq_domain; + + for (i = 0; i < PCI_NUM_INTX; i++) { + reg = j721e_pcie_intd_readl(pcie, ENABLE_REG_SYS_0); + reg |= INTx_EN(i); + j721e_pcie_intd_writel(pcie, ENABLE_REG_SYS_0, reg); + } + + return 0; +} + static int j721e_pcie_start_link(struct cdns_pcie *cdns_pcie) { struct j721e_pcie *pcie = dev_get_drvdata(cdns_pcie->dev); @@ -385,6 +472,10 @@ static int j721e_pcie_probe(struct platform_device *pdev) goto err_get_sync; } + ret = j721e_pcie_config_legacy_irq(pcie); + if (ret < 0) + goto err_get_sync; + bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc)); if (!bridge) { ret = -ENOMEM;