From patchwork Tue Sep 10 12:27:04 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Ilpo_J=C3=A4rvinen?= X-Patchwork-Id: 827273 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AEC231922C4; Tue, 10 Sep 2024 12:29:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.17 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725971343; cv=none; b=ivp4v6k7nQDmHgdkIuNjaHdwum93GQFpaG7Plv57jq7cX3BrkorapHHWrJFztg1OCIt2Y1KE+0ThROEHT7EEVrRFBQ84cbRUeeMjEiwnn7+Cxk1lYhou39mk0fdBooznwf/Uzc8v43ax6WkcnUVexN/sza8xpfk/CQRU48TBTSQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725971343; c=relaxed/simple; bh=rNvQYpl8KHgRlyXwOe4i9Xyk4ZwUT9nzj83+r99OBho=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=emQk/hOfxlm5yYQow0HiYE07YqLWVyiZvkme4BuRFqW5e/Il6gZmmxeapb3NUiu9E5ih/IV+KZYcLGflG7AD/sbRblfFAHweLZsvdryNoeCmgcXTiz0IdRRnsBvZGaGbTIbcz6m0zelUbtHl5PYgTCdNEPnOyDDVNvvYi37qQY8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=oC/AOfy8; arc=none smtp.client-ip=198.175.65.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="oC/AOfy8" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1725971342; x=1757507342; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=rNvQYpl8KHgRlyXwOe4i9Xyk4ZwUT9nzj83+r99OBho=; b=oC/AOfy8O0dpJvdjCcG389jl5mXIb82Fe2YIbIAlSlaLcIQ6VDQSqaKS PhmwPc9UeDBEb95KlEkyM85qdrWbRW8mX/MYTShPCoQNFrPSoiSEbiQtJ 8miQrLkm/aWJuPq1RWW14Dy7osDw46gsNzzbQ+P/q0g5SKA1lqaT9OxAW IUgOmoiM4sDUiwd2g+wSgQeTtav1c8W+F9lyDhCEJyE0QXazV4JpAjZAh GC03Ao1fEV8kaqCQ2fBTRYsP9CLhwhZJOZH5DbiQ0VYnFnvtJiPUx92MO +q4YGIWPiYUEy5GNq693e7V8GYATCmfjx0F9eD2ezW6jioR6c4zjx8Li6 Q==; X-CSE-ConnectionGUID: Rljb65wZT1+NhXEchn44pQ== X-CSE-MsgGUID: aWMTEavaTJW9hiL1giXcEQ== X-IronPort-AV: E=McAfee;i="6700,10204,11190"; a="24864357" X-IronPort-AV: E=Sophos;i="6.10,217,1719903600"; d="scan'208";a="24864357" Received: from orviesa003.jf.intel.com ([10.64.159.143]) by orvoesa109.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Sep 2024 05:29:01 -0700 X-CSE-ConnectionGUID: 6cfgcBH5Sjq7EfTN9Fss4w== X-CSE-MsgGUID: S+rNGbMlT2GfOv3PHs57Wg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,217,1719903600"; d="scan'208";a="71787597" Received: from ijarvine-desk1.ger.corp.intel.com (HELO localhost) ([10.245.245.224]) by ORVIESA003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Sep 2024 05:28:53 -0700 From: =?utf-8?q?Ilpo_J=C3=A4rvinen?= To: linux-pci@vger.kernel.org, Bjorn Helgaas , Lorenzo Pieralisi , Rob Herring , =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= , "Maciej W. Rozycki" , Jonathan Cameron , Lukas Wunner , Alexandru Gagniuc , Krishna chaitanya chundru , Srinivas Pandruvada , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Smita Koralahalli , =?utf-8?q?Ilpo_?= =?utf-8?q?J=C3=A4rvinen?= , Daniel Lezcano , Zhang Rui , Lukasz Luba , linux-kernel@vger.kernel.org Cc: Amit Kucheria , Christophe JAILLET , Jonathan Cameron Subject: [PATCH v7 7/8] thermal: Add PCIe cooling driver Date: Tue, 10 Sep 2024 15:27:04 +0300 Message-Id: <20240910122705.4068-8-ilpo.jarvinen@linux.intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240910122705.4068-1-ilpo.jarvinen@linux.intel.com> References: <20240910122705.4068-1-ilpo.jarvinen@linux.intel.com> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add a thermal cooling driver to provide path to access PCIe bandwidth controller using the usual thermal interfaces. A cooling device is instantiated for controllable PCIe Ports from the bwctrl service driver. If registering the cooling device fails, allow bwctrl's probe to succeed regardless. As cdev in that case contains IS_ERR() pseudo "pointer", clean that up inside the probe function so the remove side doesn't need to suddenly make an odd looking IS_ERR() check. The thermal side state 0 means no throttling, i.e., maximum supported PCIe Link Speed. Signed-off-by: Ilpo Järvinen Reviewed-by: Jonathan Cameron Acked-by: Rafael J. Wysocki # From the cooling device interface perspective --- MAINTAINERS | 2 + drivers/pci/pcie/bwctrl.c | 11 +++++ drivers/thermal/Kconfig | 10 +++++ drivers/thermal/Makefile | 2 + drivers/thermal/pcie_cooling.c | 80 ++++++++++++++++++++++++++++++++++ include/linux/pci-bwctrl.h | 28 ++++++++++++ 6 files changed, 133 insertions(+) create mode 100644 drivers/thermal/pcie_cooling.c create mode 100644 include/linux/pci-bwctrl.h diff --git a/MAINTAINERS b/MAINTAINERS index d2e418350883..47542dcb9259 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17674,6 +17674,8 @@ M: Ilpo Järvinen L: linux-pci@vger.kernel.org S: Supported F: drivers/pci/pcie/bwctrl.c +F: drivers/thermal/pcie_cooling.c +F: include/linux/pci-bwctrl.h PCIE DRIVER FOR AMAZON ANNAPURNA LABS M: Jonathan Chocron diff --git a/drivers/pci/pcie/bwctrl.c b/drivers/pci/pcie/bwctrl.c index cc245aaf8d5e..592a14183df8 100644 --- a/drivers/pci/pcie/bwctrl.c +++ b/drivers/pci/pcie/bwctrl.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include @@ -38,10 +39,12 @@ * struct pcie_bwctrl_data - PCIe bandwidth controller * @set_speed_mutex: Serializes link speed changes * @lbms_count: Count for LBMS (since last reset) + * @cdev: thermal cooling device associated with the port */ struct pcie_bwctrl_data { struct mutex set_speed_mutex; atomic_t lbms_count; + struct thermal_cooling_device *cdev; }; #ifdef CONFIG_PCIE_BWCTRL @@ -341,6 +344,11 @@ static int pcie_bwnotif_probe(struct pcie_device *srv) pci_dbg(port, "enabled with IRQ %d\n", srv->irq); + /* Don't fail on errors. Don't leave IS_ERR() "pointer" into ->cdev */ + port->link_bwctrl->cdev = pcie_cooling_device_register(port); + if (IS_ERR(port->link_bwctrl->cdev)) + port->link_bwctrl->cdev = NULL; + return 0; } @@ -348,6 +356,9 @@ static void pcie_bwnotif_remove(struct pcie_device *srv) { struct pcie_bwctrl_data *data = get_service_data(srv); + if (data->cdev) + pcie_cooling_device_unregister(data->cdev); + pcie_bwnotif_disable(srv->port); scoped_guard(rwsem_write, &pcie_bwctrl_remove_rwsem) srv->port->link_bwctrl = NULL; diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index ed16897584b4..648e0478d9d6 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -211,6 +211,16 @@ config DEVFREQ_THERMAL If you want this support, you should say Y here. +config PCIE_THERMAL + bool "PCIe cooling support" + depends on PCIEPORTBUS + select PCIE_BWCTRL + help + This implements PCIe cooling mechanism through bandwidth reduction + for PCIe devices. + + If you want this support, you should say Y here. + config THERMAL_EMULATION bool "Thermal emulation mode support" help diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index ce7a4752ef52..33cb16b06ba5 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -31,6 +31,8 @@ thermal_sys-$(CONFIG_CPU_IDLE_THERMAL) += cpuidle_cooling.o # devfreq cooling thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o +thermal_sys-$(CONFIG_PCIE_THERMAL) += pcie_cooling.o + obj-$(CONFIG_K3_THERMAL) += k3_bandgap.o k3_j72xx_bandgap.o # platform thermal drivers obj-y += broadcom/ diff --git a/drivers/thermal/pcie_cooling.c b/drivers/thermal/pcie_cooling.c new file mode 100644 index 000000000000..a876d64f1582 --- /dev/null +++ b/drivers/thermal/pcie_cooling.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * PCIe cooling device + * + * Copyright (C) 2023-2024 Intel Corporation + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define COOLING_DEV_TYPE_PREFIX "PCIe_Port_Link_Speed_" + +static int pcie_cooling_get_max_level(struct thermal_cooling_device *cdev, unsigned long *state) +{ + struct pci_dev *port = cdev->devdata; + + /* cooling state 0 is same as the maximum PCIe speed */ + *state = port->subordinate->max_bus_speed - PCIE_SPEED_2_5GT; + + return 0; +} + +static int pcie_cooling_get_cur_level(struct thermal_cooling_device *cdev, unsigned long *state) +{ + struct pci_dev *port = cdev->devdata; + + /* cooling state 0 is same as the maximum PCIe speed */ + *state = cdev->max_state - (port->subordinate->cur_bus_speed - PCIE_SPEED_2_5GT); + + return 0; +} + +static int pcie_cooling_set_cur_level(struct thermal_cooling_device *cdev, unsigned long state) +{ + struct pci_dev *port = cdev->devdata; + enum pci_bus_speed speed; + + /* cooling state 0 is same as the maximum PCIe speed */ + speed = (cdev->max_state - state) + PCIE_SPEED_2_5GT; + + return pcie_set_target_speed(port, speed, true); +} + +static struct thermal_cooling_device_ops pcie_cooling_ops = { + .get_max_state = pcie_cooling_get_max_level, + .get_cur_state = pcie_cooling_get_cur_level, + .set_cur_state = pcie_cooling_set_cur_level, +}; + +struct thermal_cooling_device *pcie_cooling_device_register(struct pci_dev *port) +{ + char *name __free(kfree) = + kasprintf(GFP_KERNEL, COOLING_DEV_TYPE_PREFIX "%s", pci_name(port)); + if (!name) + return ERR_PTR(-ENOMEM); + + return thermal_cooling_device_register(name, port, &pcie_cooling_ops); +} + +void pcie_cooling_device_unregister(struct thermal_cooling_device *cdev) +{ + thermal_cooling_device_unregister(cdev); +} + +/* For bus_speed <-> state arithmetic */ +static_assert(PCIE_SPEED_2_5GT + 1 == PCIE_SPEED_5_0GT); +static_assert(PCIE_SPEED_5_0GT + 1 == PCIE_SPEED_8_0GT); +static_assert(PCIE_SPEED_8_0GT + 1 == PCIE_SPEED_16_0GT); +static_assert(PCIE_SPEED_16_0GT + 1 == PCIE_SPEED_32_0GT); +static_assert(PCIE_SPEED_32_0GT + 1 == PCIE_SPEED_64_0GT); + +MODULE_AUTHOR("Ilpo Järvinen "); +MODULE_DESCRIPTION("PCIe cooling driver"); diff --git a/include/linux/pci-bwctrl.h b/include/linux/pci-bwctrl.h new file mode 100644 index 000000000000..cee07127455b --- /dev/null +++ b/include/linux/pci-bwctrl.h @@ -0,0 +1,28 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * PCIe bandwidth controller + * + * Copyright (C) 2023-2024 Intel Corporation + */ + +#ifndef LINUX_PCI_BWCTRL_H +#define LINUX_PCI_BWCTRL_H + +#include + +struct thermal_cooling_device; + +#ifdef CONFIG_PCIE_THERMAL +struct thermal_cooling_device *pcie_cooling_device_register(struct pci_dev *port); +void pcie_cooling_device_unregister(struct thermal_cooling_device *cdev); +#else +static inline struct thermal_cooling_device *pcie_cooling_device_register(struct pci_dev *port) +{ + return NULL; +} +static inline void pcie_cooling_device_unregister(struct thermal_cooling_device *cdev) +{ +} +#endif + +#endif