From 6523d3b2ffa238ac033c34a726617061d6a744aa Mon Sep 17 00:00:00 2001 From: Iwona Winiarska Date: Tue, 8 Feb 2022 16:36:30 +0100 Subject: peci: Add core infrastructure Intel processors provide access for various services designed to support processor and DRAM thermal management, platform manageability and processor interface tuning and diagnostics. Those services are available via the Platform Environment Control Interface (PECI) that provides a communication channel between the processor and the Baseboard Management Controller (BMC) or other platform management device. This change introduces PECI subsystem by adding the initial core module and API for controller drivers. Co-developed-by: Jason M Bills Co-developed-by: Jae Hyun Yoo Reviewed-by: Pierre-Louis Bossart Acked-by: Joel Stanley Signed-off-by: Jason M Bills Signed-off-by: Jae Hyun Yoo Signed-off-by: Iwona Winiarska Link: https://lore.kernel.org/r/20220208153639.255278-5-iwona.winiarska@intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/peci/Kconfig | 15 +++++ drivers/peci/Makefile | 5 ++ drivers/peci/core.c | 158 ++++++++++++++++++++++++++++++++++++++++++++++++ drivers/peci/internal.h | 16 +++++ 4 files changed, 194 insertions(+) create mode 100644 drivers/peci/Kconfig create mode 100644 drivers/peci/Makefile create mode 100644 drivers/peci/core.c create mode 100644 drivers/peci/internal.h (limited to 'drivers/peci') diff --git a/drivers/peci/Kconfig b/drivers/peci/Kconfig new file mode 100644 index 000000000000..71a4ad81225a --- /dev/null +++ b/drivers/peci/Kconfig @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0-only + +menuconfig PECI + tristate "PECI support" + help + The Platform Environment Control Interface (PECI) is an interface + that provides a communication channel to Intel processors and + chipset components from external monitoring or control devices. + + If you are building a Baseboard Management Controller (BMC) kernel + for Intel platform say Y here and also to the specific driver for + your adapter(s) below. If unsure say N. + + This support is also available as a module. If so, the module + will be called peci. diff --git a/drivers/peci/Makefile b/drivers/peci/Makefile new file mode 100644 index 000000000000..e789a354e842 --- /dev/null +++ b/drivers/peci/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0-only + +# Core functionality +peci-y := core.o +obj-$(CONFIG_PECI) += peci.o diff --git a/drivers/peci/core.c b/drivers/peci/core.c new file mode 100644 index 000000000000..73ad0a47fa9d --- /dev/null +++ b/drivers/peci/core.c @@ -0,0 +1,158 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (c) 2018-2021 Intel Corporation + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "internal.h" + +static DEFINE_IDA(peci_controller_ida); + +static void peci_controller_dev_release(struct device *dev) +{ + struct peci_controller *controller = to_peci_controller(dev); + + mutex_destroy(&controller->bus_lock); + ida_free(&peci_controller_ida, controller->id); + kfree(controller); +} + +struct device_type peci_controller_type = { + .release = peci_controller_dev_release, +}; + +static struct peci_controller *peci_controller_alloc(struct device *dev, + struct peci_controller_ops *ops) +{ + struct peci_controller *controller; + int ret; + + if (!ops->xfer) + return ERR_PTR(-EINVAL); + + controller = kzalloc(sizeof(*controller), GFP_KERNEL); + if (!controller) + return ERR_PTR(-ENOMEM); + + ret = ida_alloc_max(&peci_controller_ida, U8_MAX, GFP_KERNEL); + if (ret < 0) + goto err; + controller->id = ret; + + controller->ops = ops; + + controller->dev.parent = dev; + controller->dev.bus = &peci_bus_type; + controller->dev.type = &peci_controller_type; + + device_initialize(&controller->dev); + + mutex_init(&controller->bus_lock); + + return controller; + +err: + kfree(controller); + return ERR_PTR(ret); +} + +static void unregister_controller(void *_controller) +{ + struct peci_controller *controller = _controller; + + device_unregister(&controller->dev); + + fwnode_handle_put(controller->dev.fwnode); + + pm_runtime_disable(&controller->dev); +} + +/** + * devm_peci_controller_add() - add PECI controller + * @dev: device for devm operations + * @ops: pointer to controller specific methods + * + * In final stage of its probe(), peci_controller driver calls + * devm_peci_controller_add() to register itself with the PECI bus. + * + * Return: Pointer to the newly allocated controller or ERR_PTR() in case of failure. + */ +struct peci_controller *devm_peci_controller_add(struct device *dev, + struct peci_controller_ops *ops) +{ + struct peci_controller *controller; + int ret; + + controller = peci_controller_alloc(dev, ops); + if (IS_ERR(controller)) + return controller; + + ret = dev_set_name(&controller->dev, "peci-%d", controller->id); + if (ret) + goto err_put; + + pm_runtime_no_callbacks(&controller->dev); + pm_suspend_ignore_children(&controller->dev, true); + pm_runtime_enable(&controller->dev); + + device_set_node(&controller->dev, fwnode_handle_get(dev_fwnode(dev))); + + ret = device_add(&controller->dev); + if (ret) + goto err_fwnode; + + ret = devm_add_action_or_reset(dev, unregister_controller, controller); + if (ret) + return ERR_PTR(ret); + + return controller; + +err_fwnode: + fwnode_handle_put(controller->dev.fwnode); + + pm_runtime_disable(&controller->dev); + +err_put: + put_device(&controller->dev); + + return ERR_PTR(ret); +} +EXPORT_SYMBOL_NS_GPL(devm_peci_controller_add, PECI); + +struct bus_type peci_bus_type = { + .name = "peci", +}; + +static int __init peci_init(void) +{ + int ret; + + ret = bus_register(&peci_bus_type); + if (ret < 0) { + pr_err("peci: failed to register PECI bus type!\n"); + return ret; + } + + return 0; +} +module_init(peci_init); + +static void __exit peci_exit(void) +{ + bus_unregister(&peci_bus_type); +} +module_exit(peci_exit); + +MODULE_AUTHOR("Jason M Bills "); +MODULE_AUTHOR("Jae Hyun Yoo "); +MODULE_AUTHOR("Iwona Winiarska "); +MODULE_DESCRIPTION("PECI bus core module"); +MODULE_LICENSE("GPL"); diff --git a/drivers/peci/internal.h b/drivers/peci/internal.h new file mode 100644 index 000000000000..918dea745a86 --- /dev/null +++ b/drivers/peci/internal.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* Copyright (c) 2018-2021 Intel Corporation */ + +#ifndef __PECI_INTERNAL_H +#define __PECI_INTERNAL_H + +#include +#include + +struct peci_controller; + +extern struct bus_type peci_bus_type; + +extern struct device_type peci_controller_type; + +#endif /* __PECI_INTERNAL_H */ -- cgit v1.2.3-70-g09d2