peci.h

  1/* SPDX-License-Identifier: GPL-2.0-only */
  2/* Copyright (c) 2018-2021 Intel Corporation */
  3
  4#ifndef __LINUX_PECI_H
  5#define __LINUX_PECI_H
  6
  7#include <linux/device.h>
  8#include <linux/kernel.h>
  9#include <linux/mutex.h>
 10#include <linux/types.h>
 11
 12/*
 13 * Currently we don't support any PECI command over 32 bytes.
 14 */
 15#define PECI_REQUEST_MAX_BUF_SIZE 32
 16
 17struct peci_controller;
 18struct peci_request;
 19
 20/**
 21 * struct peci_controller_ops - PECI controller specific methods
 22 * @xfer: PECI transfer function
 23 *
 24 * PECI controllers may have different hardware interfaces - the drivers
 25 * implementing PECI controllers can use this structure to abstract away those
 26 * differences by exposing a common interface for PECI core.
 27 */
 28struct peci_controller_ops {
 29	int (*xfer)(struct peci_controller *controller, u8 addr, struct peci_request *req);
 30};
 31
 32/**
 33 * struct peci_controller - PECI controller
 34 * @dev: device object to register PECI controller to the device model
 35 * @ops: pointer to device specific controller operations
 36 * @bus_lock: lock used to protect multiple callers
 37 * @id: PECI controller ID
 38 *
 39 * PECI controllers usually connect to their drivers using non-PECI bus,
 40 * such as the platform bus.
 41 * Each PECI controller can communicate with one or more PECI devices.
 42 */
 43struct peci_controller {
 44	struct device dev;
 45	const struct peci_controller_ops *ops;
 46	struct mutex bus_lock; /* held for the duration of xfer */
 47	u8 id;
 48};
 49
 50struct peci_controller *devm_peci_controller_add(struct device *parent,
 51						 const struct peci_controller_ops *ops);
 52
 53static inline struct peci_controller *to_peci_controller(void *d)
 54{
 55	return container_of(d, struct peci_controller, dev);
 56}
 57
 58/**
 59 * struct peci_device - PECI device
 60 * @dev: device object to register PECI device to the device model
 61 * @info: PECI device characteristics
 62 * @info.x86_vfm: device vendor-family-model
 63 * @info.peci_revision: PECI revision supported by the PECI device
 64 * @info.socket_id: the socket ID represented by the PECI device
 65 * @addr: address used on the PECI bus connected to the parent controller
 66 * @deleted: indicates that PECI device was already deleted
 67 *
 68 * A peci_device identifies a single device (i.e. CPU) connected to a PECI bus.
 69 * The behaviour exposed to the rest of the system is defined by the PECI driver
 70 * managing the device.
 71 */
 72struct peci_device {
 73	struct device dev;
 74	struct {
 75		u32 x86_vfm;
 76		u8 peci_revision;
 77		u8 socket_id;
 78	} info;
 79	u8 addr;
 80	bool deleted;
 81};
 82
 83static inline struct peci_device *to_peci_device(struct device *d)
 84{
 85	return container_of(d, struct peci_device, dev);
 86}
 87
 88/**
 89 * struct peci_request - PECI request
 90 * @device: PECI device to which the request is sent
 91 * @tx: TX buffer specific data
 92 * @tx.buf: TX buffer
 93 * @tx.len: transfer data length in bytes
 94 * @rx: RX buffer specific data
 95 * @rx.buf: RX buffer
 96 * @rx.len: received data length in bytes
 97 *
 98 * A peci_request represents a request issued by PECI originator (TX) and
 99 * a response received from PECI responder (RX).
100 */
101struct peci_request {
102	struct peci_device *device;
103	struct {
104		u8 buf[PECI_REQUEST_MAX_BUF_SIZE];
105		u8 len;
106	} rx, tx;
107};
108
109#endif /* __LINUX_PECI_H */