include/linux/peci.h

0001 /* SPDX-License-Identifier: GPL-2.0-only */
0002 /* Copyright (c) 2018-2021 Intel Corporation */
0003
0004 #ifndef __LINUX_PECI_H
0005 #define __LINUX_PECI_H
0006
0007 #include <linux/device.h>
0008 #include <linux/kernel.h>
0009 #include <linux/mutex.h>
0010 #include <linux/types.h>
0011
0012 /*
0013  * Currently we don't support any PECI command over 32 bytes.
0014  */
0015 #define PECI_REQUEST_MAX_BUF_SIZE 32
0016
0017 struct peci_controller;
0018 struct peci_request;
0019
0020 /**
0021  * struct peci_controller_ops - PECI controller specific methods
0022  * @xfer: PECI transfer function
0023  *
0024  * PECI controllers may have different hardware interfaces - the drivers
0025  * implementing PECI controllers can use this structure to abstract away those
0026  * differences by exposing a common interface for PECI core.
0027  */
0028 struct peci_controller_ops {
0029     int (*xfer)(struct peci_controller *controller, u8 addr, struct peci_request *req);
0030 };
0031
0032 /**
0033  * struct peci_controller - PECI controller
0034  * @dev: device object to register PECI controller to the device model
0035  * @ops: pointer to device specific controller operations
0036  * @bus_lock: lock used to protect multiple callers
0037  * @id: PECI controller ID
0038  *
0039  * PECI controllers usually connect to their drivers using non-PECI bus,
0040  * such as the platform bus.
0041  * Each PECI controller can communicate with one or more PECI devices.
0042  */
0043 struct peci_controller {
0044     struct device dev;
0045     struct peci_controller_ops *ops;
0046     struct mutex bus_lock; /* held for the duration of xfer */
0047     u8 id;
0048 };
0049
0050 struct peci_controller *devm_peci_controller_add(struct device *parent,
0051                          struct peci_controller_ops *ops);
0052
0053 static inline struct peci_controller *to_peci_controller(void *d)
0054 {
0055     return container_of(d, struct peci_controller, dev);
0056 }
0057
0058 /**
0059  * struct peci_device - PECI device
0060  * @dev: device object to register PECI device to the device model
0061  * @controller: manages the bus segment hosting this PECI device
0062  * @info: PECI device characteristics
0063  * @info.family: device family
0064  * @info.model: device model
0065  * @info.peci_revision: PECI revision supported by the PECI device
0066  * @info.socket_id: the socket ID represented by the PECI device
0067  * @addr: address used on the PECI bus connected to the parent controller
0068  * @deleted: indicates that PECI device was already deleted
0069  *
0070  * A peci_device identifies a single device (i.e. CPU) connected to a PECI bus.
0071  * The behaviour exposed to the rest of the system is defined by the PECI driver
0072  * managing the device.
0073  */
0074 struct peci_device {
0075     struct device dev;
0076     struct {
0077         u16 family;
0078         u8 model;
0079         u8 peci_revision;
0080         u8 socket_id;
0081     } info;
0082     u8 addr;
0083     bool deleted;
0084 };
0085
0086 static inline struct peci_device *to_peci_device(struct device *d)
0087 {
0088     return container_of(d, struct peci_device, dev);
0089 }
0090
0091 /**
0092  * struct peci_request - PECI request
0093  * @device: PECI device to which the request is sent
0094  * @tx: TX buffer specific data
0095  * @tx.buf: TX buffer
0096  * @tx.len: transfer data length in bytes
0097  * @rx: RX buffer specific data
0098  * @rx.buf: RX buffer
0099  * @rx.len: received data length in bytes
0100  *
0101  * A peci_request represents a request issued by PECI originator (TX) and
0102  * a response received from PECI responder (RX).
0103  */
0104 struct peci_request {
0105     struct peci_device *device;
0106     struct {
0107         u8 buf[PECI_REQUEST_MAX_BUF_SIZE];
0108         u8 len;
0109     } rx, tx;
0110 };
0111
0112 #endif /* __LINUX_PECI_H */