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.family: device family
63 * @info.model: device model
64 * @info.peci_revision: PECI revision supported by the PECI device
65 * @info.socket_id: the socket ID represented by the PECI device
66 * @addr: address used on the PECI bus connected to the parent controller
67 * @deleted: indicates that PECI device was already deleted
68 *
69 * A peci_device identifies a single device (i.e. CPU) connected to a PECI bus.
70 * The behaviour exposed to the rest of the system is defined by the PECI driver
71 * managing the device.
72 */
73struct peci_device {
74	struct device dev;
75	struct {
76		u16 family;
77		u8 model;
78		u8 peci_revision;
79		u8 socket_id;
80	} info;
81	u8 addr;
82	bool deleted;
83};
84
85static inline struct peci_device *to_peci_device(struct device *d)
86{
87	return container_of(d, struct peci_device, dev);
88}
89
90/**
91 * struct peci_request - PECI request
92 * @device: PECI device to which the request is sent
93 * @tx: TX buffer specific data
94 * @tx.buf: TX buffer
95 * @tx.len: transfer data length in bytes
96 * @rx: RX buffer specific data
97 * @rx.buf: RX buffer
98 * @rx.len: received data length in bytes
99 *
100 * A peci_request represents a request issued by PECI originator (TX) and
101 * a response received from PECI responder (RX).
102 */
103struct peci_request {
104	struct peci_device *device;
105	struct {
106		u8 buf[PECI_REQUEST_MAX_BUF_SIZE];
107		u8 len;
108	} rx, tx;
109};
110
111#endif /* __LINUX_PECI_H */
112