From patchwork Mon Oct 21 06:39:20 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dilip Kota X-Patchwork-Id: 11201415 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 67FB314E5 for ; Mon, 21 Oct 2019 06:39:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 46D73214AE for ; Mon, 21 Oct 2019 06:39:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727281AbfJUGjp (ORCPT ); Mon, 21 Oct 2019 02:39:45 -0400 Received: from mga09.intel.com ([134.134.136.24]:7559 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726039AbfJUGjp (ORCPT ); Mon, 21 Oct 2019 02:39:45 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Oct 2019 23:39:45 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,322,1566889200"; d="scan'208";a="372088328" Received: from sgsxdev004.isng.intel.com (HELO localhost) ([10.226.88.13]) by orsmga005.jf.intel.com with ESMTP; 20 Oct 2019 23:39:41 -0700 From: Dilip Kota To: jingoohan1@gmail.com, gustavo.pimentel@synopsys.com, lorenzo.pieralisi@arm.com, andrew.murray@arm.com, robh@kernel.org, martin.blumenstingl@googlemail.com, linux-pci@vger.kernel.org, hch@infradead.org, devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org, andriy.shevchenko@intel.com, cheol.yong.kim@intel.com, chuanhua.lei@linux.intel.com, qi-ming.wu@intel.com, Dilip Kota Subject: [PATCH v4 3/3] pci: intel: Add sysfs attributes to configure pcie link Date: Mon, 21 Oct 2019 14:39:20 +0800 Message-Id: X-Mailer: git-send-email 2.11.0 In-Reply-To: References: In-Reply-To: References: Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org PCIe RC driver on Intel Gateway SoCs have a requirement of changing link width and speed on the fly. So add the sysfs attributes to show and store the link properties. Add the respective link resize function in pcie DesignWare framework so that Intel PCIe driver can use during link width configuration on the fly. Signed-off-by: Dilip Kota --- drivers/pci/controller/dwc/pcie-designware.c | 9 +++ drivers/pci/controller/dwc/pcie-designware.h | 3 + drivers/pci/controller/dwc/pcie-intel-gw.c | 112 ++++++++++++++++++++++++++- 3 files changed, 123 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c index 4c391bfd681a..662fdcb4f2d6 100644 --- a/drivers/pci/controller/dwc/pcie-designware.c +++ b/drivers/pci/controller/dwc/pcie-designware.c @@ -474,6 +474,15 @@ int dw_pcie_link_up(struct dw_pcie *pci) (!(val & PCIE_PORT_DEBUG1_LINK_IN_TRAINING))); } +void dw_pcie_link_width_resize(struct dw_pcie *pci, u32 lane_width) +{ + u32 val; + + val = dw_pcie_readl_dbi(pci, PCIE_PORT_MULTI_LANE_CTRL); + val &= ~(PORT_MLTI_LNK_WDTH_CHNG | PORT_MLTI_LNK_WDTH); + val |= PORT_MLTI_LNK_WDTH_CHNG | lane_width; + dw_pcie_writel_dbi(pci, PCIE_PORT_MULTI_LANE_CTRL, val); +} void dw_pcie_upconfig_setup(struct dw_pcie *pci) { diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h index 3beac10e4a4c..fcf0442341fd 100644 --- a/drivers/pci/controller/dwc/pcie-designware.h +++ b/drivers/pci/controller/dwc/pcie-designware.h @@ -67,6 +67,8 @@ #define PCIE_MSI_INTR0_STATUS 0x830 #define PCIE_PORT_MULTI_LANE_CTRL 0x8C0 +#define PORT_MLTI_LNK_WDTH GENMASK(5, 0) +#define PORT_MLTI_LNK_WDTH_CHNG BIT(6) #define PORT_MLTI_UPCFG_SUPPORT BIT(7) #define PCIE_ATU_VIEWPORT 0x900 @@ -282,6 +284,7 @@ void dw_pcie_write_dbi2(struct dw_pcie *pci, u32 reg, size_t size, u32 val); u32 dw_pcie_read_atu(struct dw_pcie *pci, u32 reg, size_t size); void dw_pcie_write_atu(struct dw_pcie *pci, u32 reg, size_t size, u32 val); int dw_pcie_link_up(struct dw_pcie *pci); +void dw_pcie_link_width_resize(struct dw_pcie *pci, u32 lane_width); void dw_pcie_upconfig_setup(struct dw_pcie *pci); void dw_pcie_link_speed_change(struct dw_pcie *pci, bool enable); void dw_pcie_link_set_n_fts(struct dw_pcie *pci, u32 n_fts); diff --git a/drivers/pci/controller/dwc/pcie-intel-gw.c b/drivers/pci/controller/dwc/pcie-intel-gw.c index 9142c70db808..b9be0921671d 100644 --- a/drivers/pci/controller/dwc/pcie-intel-gw.c +++ b/drivers/pci/controller/dwc/pcie-intel-gw.c @@ -146,6 +146,22 @@ static void intel_pcie_ltssm_disable(struct intel_pcie_port *lpp) pcie_app_wr_mask(lpp, PCIE_APP_CCR_LTSSM_ENABLE, 0, PCIE_APP_CCR); } +static const char *pcie_link_gen_to_str(int gen) +{ + switch (gen) { + case PCIE_LINK_SPEED_GEN1: + return "2.5"; + case PCIE_LINK_SPEED_GEN2: + return "5.0"; + case PCIE_LINK_SPEED_GEN3: + return "8.0"; + case PCIE_LINK_SPEED_GEN4: + return "16.0"; + default: + return "???"; + } +} + static void intel_pcie_link_setup(struct intel_pcie_port *lpp) { u32 val; @@ -444,6 +460,91 @@ static int intel_pcie_host_setup(struct intel_pcie_port *lpp) return ret; } +static ssize_t pcie_link_status_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct intel_pcie_port *lpp = dev_get_drvdata(dev); + u32 reg, width, gen; + + reg = pcie_rc_cfg_rd(lpp, PCIE_CAP_OFST + PCI_EXP_LNKCTL); + width = FIELD_GET(PCI_EXP_LNKSTA_NLW, reg >> 16); + gen = FIELD_GET(PCI_EXP_LNKSTA_CLS, reg >> 16); + + if (gen > lpp->max_speed) + return -EINVAL; + + return sprintf(buf, "Port %2u Width x%u Speed %s GT/s\n", lpp->id, + width, pcie_link_gen_to_str(gen)); +} +static DEVICE_ATTR_RO(pcie_link_status); + +static ssize_t pcie_speed_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct intel_pcie_port *lpp = dev_get_drvdata(dev); + unsigned long val; + int ret; + + ret = kstrtoul(buf, 10, &val); + if (ret) + return ret; + + if (val > lpp->max_speed) + return -EINVAL; + + lpp->link_gen = val; + intel_pcie_max_speed_setup(lpp); + dw_pcie_link_speed_change(&lpp->pci, false); + dw_pcie_link_speed_change(&lpp->pci, true); + + return len; +} +static DEVICE_ATTR_WO(pcie_speed); + +/* + * Link width change on the fly is not always successful. + * It also depends on the partner. + */ +static ssize_t pcie_width_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct intel_pcie_port *lpp = dev_get_drvdata(dev); + unsigned long val; + int ret; + + lpp = dev_get_drvdata(dev); + + ret = kstrtoul(buf, 10, &val); + if (ret) + return ret; + + if (val > lpp->max_width) + return -EINVAL; + + /* HW auto bandwidth negotiation must be enabled */ + pcie_rc_cfg_wr_mask(lpp, PCI_EXP_LNKCTL_HAWD, 0, + PCIE_CAP_OFST + PCI_EXP_LNKCTL); + dw_pcie_link_width_resize(&lpp->pci, val); + + return len; +} +static DEVICE_ATTR_WO(pcie_width); + +static struct attribute *pcie_cfg_attrs[] = { + &dev_attr_pcie_link_status.attr, + &dev_attr_pcie_speed.attr, + &dev_attr_pcie_width.attr, + NULL, +}; +ATTRIBUTE_GROUPS(pcie_cfg); + +static int intel_pcie_sysfs_init(struct intel_pcie_port *lpp) +{ + return devm_device_add_groups(lpp->pci.dev, pcie_cfg_groups); +} + static void __intel_pcie_remove(struct intel_pcie_port *lpp) { intel_pcie_core_irq_disable(lpp); @@ -490,8 +591,17 @@ static int intel_pcie_rc_init(struct pcie_port *pp) { struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct intel_pcie_port *lpp = dev_get_drvdata(pci->dev); + int ret; - return intel_pcie_host_setup(lpp); + ret = intel_pcie_host_setup(lpp); + if (ret) + return ret; + + ret = intel_pcie_sysfs_init(lpp); + if (ret) + __intel_pcie_remove(lpp); + + return ret; } int intel_pcie_msi_init(struct pcie_port *pp)