From patchwork Fri Jul 21 07:44:38 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yoshihiro Shimoda X-Patchwork-Id: 13321505 X-Patchwork-Delegate: kw@linux.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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C0F7DC0015E for ; Fri, 21 Jul 2023 07:45:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231276AbjGUHpL (ORCPT ); Fri, 21 Jul 2023 03:45:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230416AbjGUHpI (ORCPT ); Fri, 21 Jul 2023 03:45:08 -0400 Received: from relmlie5.idc.renesas.com (relmlor1.renesas.com [210.160.252.171]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 6694119B6; Fri, 21 Jul 2023 00:45:06 -0700 (PDT) X-IronPort-AV: E=Sophos;i="6.01,220,1684767600"; d="scan'208";a="170346707" Received: from unknown (HELO relmlir6.idc.renesas.com) ([10.200.68.152]) by relmlie5.idc.renesas.com with ESMTP; 21 Jul 2023 16:45:02 +0900 Received: from localhost.localdomain (unknown [10.166.15.32]) by relmlir6.idc.renesas.com (Postfix) with ESMTP id 9764C418F5EF; Fri, 21 Jul 2023 16:45:02 +0900 (JST) From: Yoshihiro Shimoda To: jingoohan1@gmail.com, gustavo.pimentel@synopsys.com, lpieralisi@kernel.org, robh+dt@kernel.org, kw@linux.com, manivannan.sadhasivam@linaro.org, bhelgaas@google.com, kishon@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org Cc: marek.vasut+renesas@gmail.com, fancer.lancer@gmail.com, linux-pci@vger.kernel.org, devicetree@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Yoshihiro Shimoda Subject: [PATCH v18 06/20] PCI: designware-ep: Add INTx IRQs support Date: Fri, 21 Jul 2023 16:44:38 +0900 Message-Id: <20230721074452.65545-7-yoshihiro.shimoda.uh@renesas.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230721074452.65545-1-yoshihiro.shimoda.uh@renesas.com> References: <20230721074452.65545-1-yoshihiro.shimoda.uh@renesas.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add support for triggering INTx IRQs by using outbound iATU. Outbound iATU is utilized to send assert and de-assert INTx TLPs. The message is generated based on the payloadless Msg TLP with type 0x14, where 0x4 is the routing code implying the Terminate at Receiver message. The message code is specified as b1000xx for the INTx assertion and b1001xx for the INTx de-assertion. Signed-off-by: Yoshihiro Shimoda Reviewed-by: Serge Semin --- .../pci/controller/dwc/pcie-designware-ep.c | 69 +++++++++++++++++-- drivers/pci/controller/dwc/pcie-designware.h | 2 + 2 files changed, 67 insertions(+), 4 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index fe2e0d765be9..1d24ebf9686f 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -6,9 +6,11 @@ * Author: Kishon Vijay Abraham I */ +#include #include #include +#include "../../pci.h" #include "pcie-designware.h" #include #include @@ -484,14 +486,60 @@ static const struct pci_epc_ops epc_ops = { .get_features = dw_pcie_ep_get_features, }; +static int dw_pcie_ep_send_msg(struct dw_pcie_ep *ep, u8 func_no, u8 code, + u8 routing) +{ + struct dw_pcie_ob_atu_cfg atu = { 0 }; + struct pci_epc *epc = ep->epc; + int ret; + + atu.func_no = func_no; + atu.code = code; + atu.routing = routing; + atu.type = PCIE_ATU_TYPE_MSG; + atu.cpu_addr = ep->intx_mem_phys; + atu.size = epc->mem->window.page_size; + + ret = dw_pcie_ep_outbound_atu(ep, &atu); + if (ret) + return ret; + + writel(0, ep->intx_mem); + + dw_pcie_ep_unmap_addr(epc, func_no, 0, ep->intx_mem_phys); + + return 0; +} + int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no) { struct dw_pcie *pci = to_dw_pcie_from_ep(ep); struct device *dev = pci->dev; + int ret; - dev_err(dev, "EP cannot trigger INTx IRQs\n"); + if (!ep->intx_mem) { + dev_err(dev, "INTx not supported\n"); + return -EOPNOTSUPP; + } - return -EINVAL; + /* + * Even though the PCI bus specification implies the level-triggered + * INTx interrupts the kernel PCIe endpoint framework has a single + * PCI_EPC_IRQ_INTx flag defined for the legacy IRQs simulation. Thus + * this function sends the Deassert_INTx PCIe TLP after the Assert_INTx + * message with the 50 usec duration basically implementing the + * rising-edge triggering IRQ. Hopefully the interrupt controller will + * still be able to register the incoming IRQ event... + */ + ret = dw_pcie_ep_send_msg(ep, func_no, PCI_MSG_CODE_ASSERT_INTA, + PCI_MSG_TYPE_R_ROUTING_LOCAL); + if (ret) + return ret; + + usleep_range(50, 100); + + return dw_pcie_ep_send_msg(ep, func_no, PCI_MSG_CODE_DEASSERT_INTA, + PCI_MSG_TYPE_R_ROUTING_LOCAL); } EXPORT_SYMBOL_GPL(dw_pcie_ep_raise_intx_irq); @@ -622,6 +670,10 @@ void dw_pcie_ep_exit(struct dw_pcie_ep *ep) dw_pcie_edma_remove(pci); + if (ep->intx_mem) + pci_epc_mem_free_addr(epc, ep->intx_mem_phys, ep->intx_mem, + epc->mem->window.page_size); + pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem, epc->mem->window.page_size); @@ -793,9 +845,14 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep) goto err_exit_epc_mem; } + ep->intx_mem = pci_epc_mem_alloc_addr(epc, &ep->intx_mem_phys, + epc->mem->window.page_size); + if (!ep->intx_mem) + dev_warn(dev, "Failed to reserve memory for INTx\n"); + ret = dw_pcie_edma_detect(pci); if (ret) - goto err_free_epc_mem; + goto err_free_epc_mem_intx; if (ep->ops->get_features) { epc_features = ep->ops->get_features(ep); @@ -812,7 +869,11 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep) err_remove_edma: dw_pcie_edma_remove(pci); -err_free_epc_mem: +err_free_epc_mem_intx: + if (ep->intx_mem) + pci_epc_mem_free_addr(epc, ep->intx_mem_phys, ep->intx_mem, + epc->mem->window.page_size); + pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem, epc->mem->window.page_size); diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h index c626d21243b0..812c221b3f7c 100644 --- a/drivers/pci/controller/dwc/pcie-designware.h +++ b/drivers/pci/controller/dwc/pcie-designware.h @@ -365,6 +365,8 @@ struct dw_pcie_ep { unsigned long *ob_window_map; void __iomem *msi_mem; phys_addr_t msi_mem_phys; + void __iomem *intx_mem; + phys_addr_t intx_mem_phys; struct pci_epf_bar *epf_bar[PCI_STD_NUM_BARS]; };