From patchwork Wed Jul 8 09:30:08 2020 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: 11651153 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B0CC26C1 for ; Wed, 8 Jul 2020 09:31:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 969112065F for ; Wed, 8 Jul 2020 09:31:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="i/KslzbF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728349AbgGHJaw (ORCPT ); Wed, 8 Jul 2020 05:30:52 -0400 Received: from fllv0015.ext.ti.com ([198.47.19.141]:38926 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726445AbgGHJav (ORCPT ); Wed, 8 Jul 2020 05:30:51 -0400 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 0689UcY4109455; Wed, 8 Jul 2020 04:30:38 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1594200638; bh=MZf42sPBwBopHgxh/3zJoW1MM7sBcf1j/itzNs7qpps=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=i/KslzbFcr01l4BlPbqXIPHif/xZ8ESa/x4+fXWWCM1fm8F3lQubBu/oX/OyNZ8om fJ+CkoyFFFYbVZB4dS4StrG8q2cH3KfhIt7C43cOFvuelbIOobzAebLDK7Kfhj6ML2 8SCskCRcKTSiMwwDQYRiscTsDIDiympzti4YV5ko= Received: from DLEE105.ent.ti.com (dlee105.ent.ti.com [157.170.170.35]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 0689Uc0k043589 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 8 Jul 2020 04:30:38 -0500 Received: from DLEE108.ent.ti.com (157.170.170.38) by DLEE105.ent.ti.com (157.170.170.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3; Wed, 8 Jul 2020 04:30:38 -0500 Received: from fllv0040.itg.ti.com (10.64.41.20) by DLEE108.ent.ti.com (157.170.170.38) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3 via Frontend Transport; Wed, 8 Jul 2020 04:30:38 -0500 Received: from a0393678ub.india.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0040.itg.ti.com (8.15.2/8.15.2) with ESMTP id 0689UJEL098512; Wed, 8 Jul 2020 04:30:35 -0500 From: Kishon Vijay Abraham I To: Tom Joseph , Bjorn Helgaas , Rob Herring , Kishon Vijay Abraham I , Lorenzo Pieralisi , Arnd Bergmann CC: Greg Kroah-Hartman , , , , , Subject: [PATCH v6 04/14] PCI: cadence: Add support to start link and verify link status Date: Wed, 8 Jul 2020 15:00:08 +0530 Message-ID: <20200708093018.28474-5-kishon@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200708093018.28474-1-kishon@ti.com> References: <20200708093018.28474-1-kishon@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add cdns_pcie_ops to start link and verify link status. The registers to start link and to check link status is in Platform specific PCIe wrapper. Add support for platform specific drivers to add callback functions for the PCIe Cadence core to start link and verify link status. Signed-off-by: Kishon Vijay Abraham I Reviewed-by: Rob Herring --- .../pci/controller/cadence/pcie-cadence-ep.c | 8 ++++ .../controller/cadence/pcie-cadence-host.c | 28 ++++++++++++++ drivers/pci/controller/cadence/pcie-cadence.h | 37 ++++++++++++++++++- 3 files changed, 72 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c index c6eb2db94680..034cb3cf726e 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c @@ -357,8 +357,10 @@ static int cdns_pcie_ep_start(struct pci_epc *epc) { struct cdns_pcie_ep *ep = epc_get_drvdata(epc); struct cdns_pcie *pcie = &ep->pcie; + struct device *dev = pcie->dev; struct pci_epf *epf; u32 cfg; + int ret; /* * BIT(0) is hardwired to 1, hence function 0 is always enabled @@ -369,6 +371,12 @@ static int cdns_pcie_ep_start(struct pci_epc *epc) cfg |= BIT(epf->func_no); cdns_pcie_writel(pcie, CDNS_PCIE_LM_EP_FUNC_CFG, cfg); + ret = cdns_pcie_start_link(pcie); + if (ret) { + dev_err(dev, "Failed to start link\n"); + return ret; + } + return 0; } diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c index 030e828bfd4c..de02fadc4809 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-host.c +++ b/drivers/pci/controller/cadence/pcie-cadence-host.c @@ -3,6 +3,7 @@ // Cadence PCIe host controller driver. // Author: Cyrille Pitchen +#include #include #include #include @@ -419,6 +420,23 @@ static int cdns_pcie_host_init(struct device *dev, return err; } +static int cdns_pcie_host_wait_for_link(struct cdns_pcie *pcie) +{ + struct device *dev = pcie->dev; + int retries; + + /* Check if the link is up or not */ + for (retries = 0; retries < LINK_WAIT_MAX_RETRIES; retries++) { + if (cdns_pcie_link_up(pcie)) { + dev_info(dev, "Link up\n"); + return 0; + } + usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX); + } + + return -ETIMEDOUT; +} + int cdns_pcie_host_setup(struct cdns_pcie_rc *rc) { struct device *dev = rc->pcie.dev; @@ -467,6 +485,16 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc) pcie->mem_res = res; + ret = cdns_pcie_start_link(pcie); + if (ret) { + dev_err(dev, "Failed to start link\n"); + return ret; + } + + ret = cdns_pcie_host_wait_for_link(pcie); + if (ret) + dev_dbg(dev, "PCIe link never came up\n"); + for (bar = RP_BAR0; bar <= RP_NO_BAR; bar++) rc->avail_ib_bar[bar] = true; diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h index a45c11158f49..54e10caf2d4b 100644 --- a/drivers/pci/controller/cadence/pcie-cadence.h +++ b/drivers/pci/controller/cadence/pcie-cadence.h @@ -10,6 +10,11 @@ #include #include +/* Parameters for the waiting for link up routine */ +#define LINK_WAIT_MAX_RETRIES 10 +#define LINK_WAIT_USLEEP_MIN 90000 +#define LINK_WAIT_USLEEP_MAX 100000 + /* * Local Management Registers */ @@ -245,12 +250,20 @@ enum cdns_pcie_msg_routing { MSG_ROUTING_GATHER, }; +struct cdns_pcie_ops { + int (*start_link)(struct cdns_pcie *pcie); + void (*stop_link)(struct cdns_pcie *pcie); + bool (*link_up)(struct cdns_pcie *pcie); +}; + /** * struct cdns_pcie - private data for Cadence PCIe controller drivers * @reg_base: IO mapped register base * @mem_res: start/end offsets in the physical system memory to map PCI accesses * @is_rc: tell whether the PCIe controller mode is Root Complex or Endpoint. * @bus: In Root Complex mode, the bus number + * @ops: Platform specific ops to control various inputs from Cadence PCIe + * wrapper */ struct cdns_pcie { void __iomem *reg_base; @@ -261,7 +274,7 @@ struct cdns_pcie { int phy_count; struct phy **phy; struct device_link **link; - const struct cdns_pcie_common_ops *ops; + const struct cdns_pcie_ops *ops; }; /** @@ -426,6 +439,28 @@ static inline u32 cdns_pcie_ep_fn_readl(struct cdns_pcie *pcie, u8 fn, u32 reg) return readl(pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg); } +static inline int cdns_pcie_start_link(struct cdns_pcie *pcie) +{ + if (pcie->ops->start_link) + return pcie->ops->start_link(pcie); + + return 0; +} + +static inline void cdns_pcie_stop_link(struct cdns_pcie *pcie) +{ + if (pcie->ops->stop_link) + pcie->ops->stop_link(pcie); +} + +static inline bool cdns_pcie_link_up(struct cdns_pcie *pcie) +{ + if (pcie->ops->link_up) + return pcie->ops->link_up(pcie); + + return true; +} + #ifdef CONFIG_PCIE_CADENCE_HOST int cdns_pcie_host_setup(struct cdns_pcie_rc *rc); #else