1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2015-2019 Intel Corp. All rights reserved
4  * Copyright (C) 2021-2022 Linaro Ltd
5  */
6 #ifndef __RPMB_H__
7 #define __RPMB_H__
8 
9 #include <linux/device.h>
10 #include <linux/types.h>
11 
12 /**
13  * enum rpmb_type - type of underlying storage technology
14  *
15  * @RPMB_TYPE_EMMC  : emmc (JESD84-B50.1)
16  * @RPMB_TYPE_UFS   : UFS (JESD220)
17  * @RPMB_TYPE_NVME  : NVM Express
18  */
19 enum rpmb_type {
20 	RPMB_TYPE_EMMC,
21 	RPMB_TYPE_UFS,
22 	RPMB_TYPE_NVME,
23 };
24 
25 /**
26  * struct rpmb_descr - RPMB description provided by the underlying block device
27  *
28  * @type             : block device type
29  * @route_frames     : routes frames to and from the RPMB device
30  * @dev_id           : unique device identifier read from the hardware
31  * @dev_id_len       : length of unique device identifier
32  * @reliable_wr_count: number of sectors that can be written in one access
33  * @capacity         : capacity of the device in units of 128K
34  *
35  * @dev_id is intended to be used as input when deriving the authenticaion key.
36  */
37 struct rpmb_descr {
38 	enum rpmb_type type;
39 	int (*route_frames)(struct device *dev, u8 *req, unsigned int req_len,
40 			    u8 *resp, unsigned int resp_len);
41 	u8 *dev_id;
42 	size_t dev_id_len;
43 	u16 reliable_wr_count;
44 	u16 capacity;
45 };
46 
47 /**
48  * struct rpmb_dev - device which can support RPMB partition
49  *
50  * @dev              : device
51  * @id               : device_id
52  * @list_node        : linked list node
53  * @descr            : RPMB description
54  */
55 struct rpmb_dev {
56 	struct device dev;
57 	int id;
58 	struct list_head list_node;
59 	struct rpmb_descr descr;
60 };
61 
62 #define to_rpmb_dev(x)		container_of((x), struct rpmb_dev, dev)
63 
64 #if IS_ENABLED(CONFIG_RPMB)
65 struct rpmb_dev *rpmb_dev_get(struct rpmb_dev *rdev);
66 void rpmb_dev_put(struct rpmb_dev *rdev);
67 struct rpmb_dev *rpmb_dev_find_device(const void *data,
68 				      const struct rpmb_dev *start,
69 				      int (*match)(struct device *dev,
70 						   const void *data));
71 int rpmb_interface_register(struct class_interface *intf);
72 void rpmb_interface_unregister(struct class_interface *intf);
73 struct rpmb_dev *rpmb_dev_register(struct device *dev,
74 				   struct rpmb_descr *descr);
75 int rpmb_dev_unregister(struct rpmb_dev *rdev);
76 
77 int rpmb_route_frames(struct rpmb_dev *rdev, u8 *req,
78 		      unsigned int req_len, u8 *resp, unsigned int resp_len);
79 
80 #else
rpmb_dev_get(struct rpmb_dev * rdev)81 static inline struct rpmb_dev *rpmb_dev_get(struct rpmb_dev *rdev)
82 {
83 	return NULL;
84 }
85 
rpmb_dev_put(struct rpmb_dev * rdev)86 static inline void rpmb_dev_put(struct rpmb_dev *rdev) { }
87 
88 static inline struct rpmb_dev *
rpmb_dev_find_device(const void * data,const struct rpmb_dev * start,int (* match)(struct device * dev,const void * data))89 rpmb_dev_find_device(const void *data, const struct rpmb_dev *start,
90 		     int (*match)(struct device *dev, const void *data))
91 {
92 	return NULL;
93 }
94 
rpmb_interface_register(struct class_interface * intf)95 static inline int rpmb_interface_register(struct class_interface *intf)
96 {
97 	return -EOPNOTSUPP;
98 }
99 
rpmb_interface_unregister(struct class_interface * intf)100 static inline void rpmb_interface_unregister(struct class_interface *intf)
101 {
102 }
103 
104 static inline struct rpmb_dev *
rpmb_dev_register(struct device * dev,struct rpmb_descr * descr)105 rpmb_dev_register(struct device *dev, struct rpmb_descr *descr)
106 {
107 	return NULL;
108 }
109 
rpmb_dev_unregister(struct rpmb_dev * dev)110 static inline int rpmb_dev_unregister(struct rpmb_dev *dev)
111 {
112 	return 0;
113 }
114 
rpmb_route_frames(struct rpmb_dev * rdev,u8 * req,unsigned int req_len,u8 * resp,unsigned int resp_len)115 static inline int rpmb_route_frames(struct rpmb_dev *rdev, u8 *req,
116 				    unsigned int req_len, u8 *resp,
117 				    unsigned int resp_len)
118 {
119 	return -EOPNOTSUPP;
120 }
121 #endif /* CONFIG_RPMB */
122 
123 #endif /* __RPMB_H__ */
124