From patchwork Sun Jan 24 15:09:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunihiko Hayashi X-Patchwork-Id: 1430917 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4DNxJq4Fytz9sVw for ; Mon, 25 Jan 2021 02:10:51 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726481AbhAXPKm (ORCPT ); Sun, 24 Jan 2021 10:10:42 -0500 Received: from mx.socionext.com ([202.248.49.38]:26509 "EHLO mx.socionext.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726468AbhAXPKb (ORCPT ); Sun, 24 Jan 2021 10:10:31 -0500 Received: from unknown (HELO iyokan2-ex.css.socionext.com) ([172.31.9.54]) by mx.socionext.com with ESMTP; 25 Jan 2021 00:09:44 +0900 Received: from mail.mfilter.local (m-filter-1 [10.213.24.61]) by iyokan2-ex.css.socionext.com (Postfix) with ESMTP id 7693A205902B; Mon, 25 Jan 2021 00:09:44 +0900 (JST) Received: from 172.31.9.51 (172.31.9.51) by m-FILTER with ESMTP; Mon, 25 Jan 2021 00:09:44 +0900 Received: from plum.e01.socionext.com (unknown [10.213.132.32]) by kinkan2.css.socionext.com (Postfix) with ESMTP id DABBDB1D40; Mon, 25 Jan 2021 00:09:43 +0900 (JST) From: Kunihiko Hayashi To: Lorenzo Pieralisi , Rob Herring , Bjorn Helgaas , Kishon Vijay Abraham I Cc: linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Masami Hiramatsu , Jassi Brar , Kunihiko Hayashi Subject: [PATCH v2 1/3] PCI: endpoint: Add 'started' to pci_epc to set whether the controller is started Date: Mon, 25 Jan 2021 00:09:35 +0900 Message-Id: <1611500977-24816-2-git-send-email-hayashi.kunihiko@socionext.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1611500977-24816-1-git-send-email-hayashi.kunihiko@socionext.com> References: <1611500977-24816-1-git-send-email-hayashi.kunihiko@socionext.com> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org This adds a member 'started' as a boolean value to struct pci_epc to set whether the controller is started, and also adds a function to get the value. Signed-off-by: Kunihiko Hayashi --- drivers/pci/endpoint/pci-epc-core.c | 2 ++ include/linux/pci-epc.h | 7 +++++++ 2 files changed, 9 insertions(+) diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index cc8f9eb..2904175 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -174,6 +174,7 @@ void pci_epc_stop(struct pci_epc *epc) mutex_lock(&epc->lock); epc->ops->stop(epc); + epc->started = false; mutex_unlock(&epc->lock); } EXPORT_SYMBOL_GPL(pci_epc_stop); @@ -196,6 +197,7 @@ int pci_epc_start(struct pci_epc *epc) mutex_lock(&epc->lock); ret = epc->ops->start(epc); + epc->started = true; mutex_unlock(&epc->lock); return ret; diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index b82c9b1..5808952 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -131,6 +131,7 @@ struct pci_epc_mem { * @lock: mutex to protect pci_epc ops * @function_num_map: bitmap to manage physical function number * @notifier: used to notify EPF of any EPC events (like linkup) + * @started: true if this EPC is started */ struct pci_epc { struct device dev; @@ -145,6 +146,7 @@ struct pci_epc { struct mutex lock; unsigned long function_num_map; struct atomic_notifier_head notifier; + bool started; }; /** @@ -191,6 +193,11 @@ pci_epc_register_notifier(struct pci_epc *epc, struct notifier_block *nb) return atomic_notifier_chain_register(&epc->notifier, nb); } +static inline bool pci_epc_is_started(struct pci_epc *epc) +{ + return epc->started; +} + struct pci_epc * __devm_pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, struct module *owner); From patchwork Sun Jan 24 15:09:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunihiko Hayashi X-Patchwork-Id: 1430919 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4DNxKQ131Sz9s24 for ; Mon, 25 Jan 2021 02:11:22 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726442AbhAXPLO (ORCPT ); Sun, 24 Jan 2021 10:11:14 -0500 Received: from mx.socionext.com ([202.248.49.38]:26502 "EHLO mx.socionext.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726363AbhAXPKx (ORCPT ); Sun, 24 Jan 2021 10:10:53 -0500 Received: from unknown (HELO kinkan2-ex.css.socionext.com) ([172.31.9.52]) by mx.socionext.com with ESMTP; 25 Jan 2021 00:09:45 +0900 Received: from mail.mfilter.local (m-filter-2 [10.213.24.62]) by kinkan2-ex.css.socionext.com (Postfix) with ESMTP id 9876D2059027; Mon, 25 Jan 2021 00:09:45 +0900 (JST) Received: from 172.31.9.51 (172.31.9.51) by m-FILTER with ESMTP; Mon, 25 Jan 2021 00:09:45 +0900 Received: from plum.e01.socionext.com (unknown [10.213.132.32]) by kinkan2.css.socionext.com (Postfix) with ESMTP id DA7B3B1D40; Mon, 25 Jan 2021 00:09:44 +0900 (JST) From: Kunihiko Hayashi To: Lorenzo Pieralisi , Rob Herring , Bjorn Helgaas , Kishon Vijay Abraham I Cc: linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Masami Hiramatsu , Jassi Brar , Kunihiko Hayashi Subject: [PATCH v2 2/3] PCI: endpoint: Add endpoint restart management Date: Mon, 25 Jan 2021 00:09:36 +0900 Message-Id: <1611500977-24816-3-git-send-email-hayashi.kunihiko@socionext.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1611500977-24816-1-git-send-email-hayashi.kunihiko@socionext.com> References: <1611500977-24816-1-git-send-email-hayashi.kunihiko@socionext.com> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add new functions to manage recovery of configuration parameters and restart the controller when asserting bus-reset from root-complex (RC). This feature is only available if bus-reset (PERST#) line is physically routed between RC and endpoint and the signal from RC affects endpoint. This feature works as follows. - This adds a polling thread, that polls and detects the bus-reset signal, and recovers configuration parameters for endpoint. The polling period is fixed at EPC_RESTART_POLL_PERIOD_MS. - After the endpoint controller starts and the user sets configuration parameters using sysfs or function drivers, once RC asserts bus-reset and endpoint can receive it, the endpoint controller will also reset and initialize configuration parameters. - If the thread detects bus-reset signal, the thread stops the controller, unbinds it, quickly binds it and restart it. The configuration paremters are restored to the user's values. Signed-off-by: Kunihiko Hayashi --- drivers/pci/endpoint/Kconfig | 9 +++ drivers/pci/endpoint/Makefile | 1 + drivers/pci/endpoint/pci-epc-restart.c | 114 +++++++++++++++++++++++++++++++++ include/linux/pci-epc.h | 15 +++++ 4 files changed, 139 insertions(+) create mode 100644 drivers/pci/endpoint/pci-epc-restart.c diff --git a/drivers/pci/endpoint/Kconfig b/drivers/pci/endpoint/Kconfig index 17bbdc9..016c82a 100644 --- a/drivers/pci/endpoint/Kconfig +++ b/drivers/pci/endpoint/Kconfig @@ -28,6 +28,15 @@ config PCI_ENDPOINT_CONFIGFS configure the endpoint function and used to bind the function with a endpoint controller. +config PCI_ENDPOINT_RESTART + bool "PCI Endpoint Restart Management Support" + depends on PCI_ENDPOINT + help + Enable restart management functions, which detects bus-reset + from root complex, and recover endpoint configuration. + This is only available if bus-reset line is physically routed + between root complex and endpoint. + source "drivers/pci/endpoint/functions/Kconfig" endmenu diff --git a/drivers/pci/endpoint/Makefile b/drivers/pci/endpoint/Makefile index 95b2fe4..7301aea 100644 --- a/drivers/pci/endpoint/Makefile +++ b/drivers/pci/endpoint/Makefile @@ -4,5 +4,6 @@ # obj-$(CONFIG_PCI_ENDPOINT_CONFIGFS) += pci-ep-cfs.o +obj-$(CONFIG_PCI_ENDPOINT_RESTART) += pci-epc-restart.o obj-$(CONFIG_PCI_ENDPOINT) += pci-epc-core.o pci-epf-core.o\ pci-epc-mem.o functions/ diff --git a/drivers/pci/endpoint/pci-epc-restart.c b/drivers/pci/endpoint/pci-epc-restart.c new file mode 100644 index 0000000..ab956be --- /dev/null +++ b/drivers/pci/endpoint/pci-epc-restart.c @@ -0,0 +1,114 @@ +// SPDX-License-Identifier: GPL-2.0 +/** + * PCI Endpoint Controller Restart Management + * + * Copyright (C) 2019-2020 Socionext Inc. + * Author: Kunihiko Hayashi + */ + +#include +#include +#include +#include +#include + +#define EPC_RESTART_POLL_PERIOD_MS 80 + +static int pci_epc_restart_thread(void *dev_id) +{ + struct pci_epc *epc = dev_id; + struct pci_epf *epf; + int ret = 0; + + dev_info(&epc->dev, "[epc-restart] thread start\n"); + + while (!kthread_should_stop()) { + if (epc->restart_poll) { + /* call polling function */ + ret = epc->restart_poll(epc->restart_poll_data); + if (!ret) { + msleep(EPC_RESTART_POLL_PERIOD_MS); + continue; + } else if (ret < 0) { + break; + } + } else { + /* wait for interrupt */ + ret = wait_for_completion_interruptible(&epc->restart_comp); + if (ret <= 0) + break; + } + + if (!pci_epc_is_started(epc)) + continue; + + /* + * After stop linkup, call unbind() once and call bind() again. + * to reload config parameters to the controller. + */ + pci_epc_stop(epc); + list_for_each_entry(epf, &epc->pci_epf, list) { + pci_epf_unbind(epf); + pci_epf_bind(epf); + } + pci_epc_start(epc); + + dev_info(&epc->dev, "[epc-restart] assert\n"); + } + + dev_info(&epc->dev, "[epc-restart] thread exit\n"); + + return ret; +} + +/** + * pci_epc_restart_init() - initialize epc-restart thread + * @epc: the EPC device + */ +int pci_epc_restart_init(struct pci_epc *epc) +{ + init_completion(&epc->restart_comp); + + epc->restart_task = kthread_run(pci_epc_restart_thread, epc, + "pci-epc-restart"); + if (IS_ERR(epc->restart_task)) + return PTR_ERR(epc->restart_task); + + return 0; +} +EXPORT_SYMBOL_GPL(pci_epc_restart_init); + +/** + * pci_epc_restart_cleanup() - clean up epc-restart thread + * @epc: the EPC device + */ +void pci_epc_restart_cleanup(struct pci_epc *epc) +{ + if (epc->restart_task) + kthread_stop(epc->restart_task); +} +EXPORT_SYMBOL_GPL(pci_epc_restart_cleanup); + +/** + * pci_epc_restart_notify() - notify to epc-restart thread + * @epc: the EPC device + */ +void pci_epc_restart_notify(struct pci_epc *epc) +{ + complete(&epc->restart_comp); +} +EXPORT_SYMBOL_GPL(pci_epc_restart_notify); + +/** + * pci_epc_restart_register_poll_func() - register polling method for restart thread + * @epc: the EPC device + * @func: polling function + * @data: data for polling function + */ +void pci_epc_restart_register_poll_func(struct pci_epc *epc, bool (*func)(void *), + void *data) +{ + epc->restart_poll = func; + epc->restart_poll_data = data; +} +EXPORT_SYMBOL_GPL(pci_epc_restart_register_poll_func); diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index 5808952..45d2592 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -132,6 +132,10 @@ struct pci_epc_mem { * @function_num_map: bitmap to manage physical function number * @notifier: used to notify EPF of any EPC events (like linkup) * @started: true if this EPC is started + * @restart_task: pointer to task for restart thread + * @restart_comp: completion object for receiving reset interrupts from RC + * @restart_poll: function to poll reset detection from RC + * @restart_poll_data: an argument that restart_poll function gets */ struct pci_epc { struct device dev; @@ -147,6 +151,11 @@ struct pci_epc { unsigned long function_num_map; struct atomic_notifier_head notifier; bool started; + /* for epc-restart */ + struct task_struct *restart_task; + struct completion restart_comp; + bool (*restart_poll)(void *func); + void *restart_poll_data; }; /** @@ -254,4 +263,10 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, phys_addr_t *phys_addr, size_t size); void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr, void __iomem *virt_addr, size_t size); +int pci_epc_restart_init(struct pci_epc *epc); +void pci_epc_restart_cleanup(struct pci_epc *epc); +void pci_epc_restart_notify(struct pci_epc *epc); +void pci_epc_restart_register_poll_func(struct pci_epc *epc, + bool (*func)(void *), void *data); + #endif /* __LINUX_PCI_EPC_H */ From patchwork Sun Jan 24 15:09:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunihiko Hayashi X-Patchwork-Id: 1430920 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4DNxL5484Tz9sCD for ; Mon, 25 Jan 2021 02:11:57 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726513AbhAXPLi (ORCPT ); Sun, 24 Jan 2021 10:11:38 -0500 Received: from mx.socionext.com ([202.248.49.38]:26509 "EHLO mx.socionext.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726014AbhAXPLP (ORCPT ); Sun, 24 Jan 2021 10:11:15 -0500 Received: from unknown (HELO kinkan2-ex.css.socionext.com) ([172.31.9.52]) by mx.socionext.com with ESMTP; 25 Jan 2021 00:09:46 +0900 Received: from mail.mfilter.local (m-filter-2 [10.213.24.62]) by kinkan2-ex.css.socionext.com (Postfix) with ESMTP id 1EB7A2059027; Mon, 25 Jan 2021 00:09:46 +0900 (JST) Received: from 172.31.9.51 (172.31.9.51) by m-FILTER with ESMTP; Mon, 25 Jan 2021 00:09:46 +0900 Received: from plum.e01.socionext.com (unknown [10.213.132.32]) by kinkan2.css.socionext.com (Postfix) with ESMTP id D3FE2B1D40; Mon, 25 Jan 2021 00:09:45 +0900 (JST) From: Kunihiko Hayashi To: Lorenzo Pieralisi , Rob Herring , Bjorn Helgaas , Kishon Vijay Abraham I Cc: linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Masami Hiramatsu , Jassi Brar , Kunihiko Hayashi Subject: [PATCH v2 3/3] PCI: uniphier-ep: Add EPC restart management support Date: Mon, 25 Jan 2021 00:09:37 +0900 Message-Id: <1611500977-24816-4-git-send-email-hayashi.kunihiko@socionext.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1611500977-24816-1-git-send-email-hayashi.kunihiko@socionext.com> References: <1611500977-24816-1-git-send-email-hayashi.kunihiko@socionext.com> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Set the polling function and call the init function to enable EPC restart management. The polling function detects that the bus-reset signal is a rising edge. Signed-off-by: Kunihiko Hayashi --- drivers/pci/controller/dwc/Kconfig | 1 + drivers/pci/controller/dwc/pcie-uniphier-ep.c | 44 ++++++++++++++++++++++++++- 2 files changed, 44 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig index 22c5529..90d400a 100644 --- a/drivers/pci/controller/dwc/Kconfig +++ b/drivers/pci/controller/dwc/Kconfig @@ -302,6 +302,7 @@ config PCIE_UNIPHIER_EP depends on OF && HAS_IOMEM depends on PCI_ENDPOINT select PCIE_DW_EP + select PCI_ENDPOINT_RESTART help Say Y here if you want PCIe endpoint controller support on UniPhier SoCs. This driver supports Pro5 SoC. diff --git a/drivers/pci/controller/dwc/pcie-uniphier-ep.c b/drivers/pci/controller/dwc/pcie-uniphier-ep.c index 69810c6..9d83850 100644 --- a/drivers/pci/controller/dwc/pcie-uniphier-ep.c +++ b/drivers/pci/controller/dwc/pcie-uniphier-ep.c @@ -26,6 +26,7 @@ #define PCL_RSTCTRL_PIPE3 BIT(0) #define PCL_RSTCTRL1 0x0020 +#define PCL_RSTCTRL_PERST_MON BIT(16) #define PCL_RSTCTRL_PERST BIT(0) #define PCL_RSTCTRL2 0x0024 @@ -60,6 +61,7 @@ struct uniphier_pcie_ep_priv { struct clk *clk, *clk_gio; struct reset_control *rst, *rst_gio; struct phy *phy; + bool bus_reset_status; const struct pci_epc_features *features; }; @@ -212,6 +214,41 @@ uniphier_pcie_get_features(struct dw_pcie_ep *ep) return priv->features; } +static bool uniphier_pcie_ep_poll_reset(void *data) +{ + struct uniphier_pcie_ep_priv *priv = data; + bool ret, status; + + if (!priv) + return false; + + status = !(readl(priv->base + PCL_RSTCTRL1) & PCL_RSTCTRL_PERST_MON); + + /* return true if the rising edge of bus reset is detected */ + ret = !!(status == false && priv->bus_reset_status == true); + priv->bus_reset_status = status; + + return ret; +} + +static int uniphier_pcie_ep_init_complete(struct dw_pcie_ep *ep) +{ + struct dw_pcie *pci = to_dw_pcie_from_ep(ep); + struct uniphier_pcie_ep_priv *priv = to_uniphier_pcie(pci); + int ret; + + /* Set up epc-restart thread */ + pci_epc_restart_register_poll_func(ep->epc, + uniphier_pcie_ep_poll_reset, priv); + /* With call of poll_reset() directly, initialize internal state */ + uniphier_pcie_ep_poll_reset(priv); + ret = pci_epc_restart_init(ep->epc); + if (ret) + dev_err(pci->dev, "Failed to initialize epc-restart (%d)\n", ret); + + return ret; +} + static const struct dw_pcie_ep_ops uniphier_pcie_ep_ops = { .ep_init = uniphier_pcie_ep_init, .raise_irq = uniphier_pcie_ep_raise_irq, @@ -318,7 +355,12 @@ static int uniphier_pcie_ep_probe(struct platform_device *pdev) return ret; priv->pci.ep.ops = &uniphier_pcie_ep_ops; - return dw_pcie_ep_init(&priv->pci.ep); + + ret = dw_pcie_ep_init(&priv->pci.ep); + if (ret) + return ret; + + return uniphier_pcie_ep_init_complete(&priv->pci.ep); } static const struct pci_epc_features uniphier_pro5_data = {