xref: /linux/drivers/ufs/core/ufs-rpmb.c (revision d30c1683aaecb93d2ab95685dc4300a33d3cea7a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * UFS OP-TEE based RPMB Driver
4  *
5  * Copyright (C) 2025 Micron Technology, Inc.
6  * Copyright (C) 2025 Qualcomm Technologies, Inc.
7  *
8  * Authors:
9  *	Bean Huo <beanhuo@micron.com>
10  *	Can Guo <can.guo@oss.qualcomm.com>
11  */
12 
13 #include <linux/module.h>
14 #include <linux/device.h>
15 #include <linux/kernel.h>
16 #include <linux/types.h>
17 #include <linux/rpmb.h>
18 #include <linux/string.h>
19 #include <linux/list.h>
20 #include <ufs/ufshcd.h>
21 #include <linux/unaligned.h>
22 #include "ufshcd-priv.h"
23 
24 #define UFS_RPMB_SEC_PROTOCOL		0xEC	/* JEDEC UFS application */
25 #define UFS_RPMB_SEC_PROTOCOL_ID	0x01	/* JEDEC UFS RPMB protocol ID, CDB byte3 */
26 
27 static const struct bus_type ufs_rpmb_bus_type = {
28 	.name = "ufs_rpmb",
29 };
30 
31 /* UFS RPMB device structure */
32 struct ufs_rpmb_dev {
33 	u8 region_id;
34 	struct device dev;
35 	struct rpmb_dev *rdev;
36 	struct ufs_hba *hba;
37 	struct list_head node;
38 };
39 
40 static int ufs_sec_submit(struct ufs_hba *hba, u16 spsp, void *buffer, size_t len, bool send)
41 {
42 	struct scsi_device *sdev = hba->ufs_rpmb_wlun;
43 	u8 cdb[12] = { };
44 
45 	cdb[0] = send ? SECURITY_PROTOCOL_OUT : SECURITY_PROTOCOL_IN;
46 	cdb[1] = UFS_RPMB_SEC_PROTOCOL;
47 	put_unaligned_be16(spsp, &cdb[2]);
48 	put_unaligned_be32(len, &cdb[6]);
49 
50 	return scsi_execute_cmd(sdev, cdb, send ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN,
51 				buffer, len, /*timeout=*/30 * HZ, 0, NULL);
52 }
53 
54 /* UFS RPMB route frames implementation */
55 static int ufs_rpmb_route_frames(struct device *dev, u8 *req, unsigned int req_len, u8 *resp,
56 					unsigned int resp_len)
57 {
58 	struct ufs_rpmb_dev *ufs_rpmb = dev_get_drvdata(dev);
59 	struct rpmb_frame *frm_out = (struct rpmb_frame *)req;
60 	bool need_result_read = true;
61 	u16 req_type, protocol_id;
62 	struct ufs_hba *hba;
63 	int ret;
64 
65 	if (!ufs_rpmb) {
66 		dev_err(dev, "Missing driver data\n");
67 		return -ENODEV;
68 	}
69 
70 	hba = ufs_rpmb->hba;
71 
72 	req_type = be16_to_cpu(frm_out->req_resp);
73 
74 	switch (req_type) {
75 	case RPMB_PROGRAM_KEY:
76 		if (req_len != sizeof(struct rpmb_frame) || resp_len != sizeof(struct rpmb_frame))
77 			return -EINVAL;
78 		break;
79 	case RPMB_GET_WRITE_COUNTER:
80 		if (req_len != sizeof(struct rpmb_frame) || resp_len != sizeof(struct rpmb_frame))
81 			return -EINVAL;
82 		need_result_read = false;
83 		break;
84 	case RPMB_WRITE_DATA:
85 		if (req_len % sizeof(struct rpmb_frame) || resp_len != sizeof(struct rpmb_frame))
86 			return -EINVAL;
87 		break;
88 	case RPMB_READ_DATA:
89 		if (req_len != sizeof(struct rpmb_frame) || resp_len % sizeof(struct rpmb_frame))
90 			return -EINVAL;
91 		need_result_read = false;
92 		break;
93 	default:
94 		dev_err(dev, "Unknown request type=0x%04x\n", req_type);
95 		return -EINVAL;
96 	}
97 
98 	protocol_id = ufs_rpmb->region_id << 8 | UFS_RPMB_SEC_PROTOCOL_ID;
99 
100 	ret = ufs_sec_submit(hba, protocol_id, req, req_len, true);
101 	if (ret) {
102 		dev_err(dev, "Command failed with ret=%d\n", ret);
103 		return ret;
104 	}
105 
106 	if (need_result_read) {
107 		struct rpmb_frame *frm_resp = (struct rpmb_frame *)resp;
108 
109 		memset(frm_resp, 0, sizeof(*frm_resp));
110 		frm_resp->req_resp = cpu_to_be16(RPMB_RESULT_READ);
111 		ret = ufs_sec_submit(hba, protocol_id, resp, resp_len, true);
112 		if (ret) {
113 			dev_err(dev, "Result read request failed with ret=%d\n", ret);
114 			return ret;
115 		}
116 	}
117 
118 	if (!ret) {
119 		ret = ufs_sec_submit(hba, protocol_id, resp, resp_len, false);
120 		if (ret)
121 			dev_err(dev, "Response read failed with ret=%d\n", ret);
122 	}
123 
124 	return ret;
125 }
126 
127 static void ufs_rpmb_device_release(struct device *dev)
128 {
129 	struct ufs_rpmb_dev *ufs_rpmb = dev_get_drvdata(dev);
130 
131 	rpmb_dev_unregister(ufs_rpmb->rdev);
132 }
133 
134 /* UFS RPMB device registration */
135 int ufs_rpmb_probe(struct ufs_hba *hba)
136 {
137 	struct ufs_rpmb_dev *ufs_rpmb, *it, *tmp;
138 	struct rpmb_dev *rdev;
139 	char *cid = NULL;
140 	int region;
141 	u32 cap;
142 	int ret;
143 
144 	if (!hba->ufs_rpmb_wlun || hba->dev_info.b_advanced_rpmb_en) {
145 		dev_info(hba->dev, "Skip OP-TEE RPMB registration\n");
146 		return -ENODEV;
147 	}
148 
149 	/* Check if device_id is available */
150 	if (!hba->dev_info.device_id) {
151 		dev_err(hba->dev, "UFS Device ID not available\n");
152 		return -EINVAL;
153 	}
154 
155 	INIT_LIST_HEAD(&hba->rpmbs);
156 
157 	struct rpmb_descr descr = {
158 		.type = RPMB_TYPE_UFS,
159 		.route_frames = ufs_rpmb_route_frames,
160 		.reliable_wr_count = hba->dev_info.rpmb_io_size,
161 	};
162 
163 	for (region = 0; region < ARRAY_SIZE(hba->dev_info.rpmb_region_size); region++) {
164 		cap = hba->dev_info.rpmb_region_size[region];
165 		if (!cap)
166 			continue;
167 
168 		ufs_rpmb = devm_kzalloc(hba->dev, sizeof(*ufs_rpmb), GFP_KERNEL);
169 		if (!ufs_rpmb) {
170 			ret = -ENOMEM;
171 			goto err_out;
172 		}
173 
174 		ufs_rpmb->hba = hba;
175 		ufs_rpmb->dev.parent = &hba->ufs_rpmb_wlun->sdev_gendev;
176 		ufs_rpmb->dev.bus = &ufs_rpmb_bus_type;
177 		ufs_rpmb->dev.release = ufs_rpmb_device_release;
178 		dev_set_name(&ufs_rpmb->dev, "ufs_rpmb%d", region);
179 
180 		/* Set driver data BEFORE device_register */
181 		dev_set_drvdata(&ufs_rpmb->dev, ufs_rpmb);
182 
183 		ret = device_register(&ufs_rpmb->dev);
184 		if (ret) {
185 			dev_err(hba->dev, "Failed to register UFS RPMB device %d\n", region);
186 			put_device(&ufs_rpmb->dev);
187 			goto err_out;
188 		}
189 
190 		/* Create unique ID by appending region number to device_id */
191 		cid = kasprintf(GFP_KERNEL, "%s-R%d", hba->dev_info.device_id, region);
192 		if (!cid) {
193 			device_unregister(&ufs_rpmb->dev);
194 			ret = -ENOMEM;
195 			goto err_out;
196 		}
197 
198 		descr.dev_id = cid;
199 		descr.dev_id_len = strlen(cid);
200 		descr.capacity = cap;
201 
202 		/* Register RPMB device */
203 		rdev = rpmb_dev_register(&ufs_rpmb->dev, &descr);
204 		if (IS_ERR(rdev)) {
205 			dev_err(hba->dev, "Failed to register UFS RPMB device.\n");
206 			device_unregister(&ufs_rpmb->dev);
207 			ret = PTR_ERR(rdev);
208 			goto err_out;
209 		}
210 
211 		kfree(cid);
212 		cid = NULL;
213 
214 		ufs_rpmb->rdev = rdev;
215 		ufs_rpmb->region_id = region;
216 
217 		list_add_tail(&ufs_rpmb->node, &hba->rpmbs);
218 
219 		dev_info(hba->dev, "UFS RPMB region %d registered (capacity=%u)\n", region, cap);
220 	}
221 
222 	return 0;
223 err_out:
224 	kfree(cid);
225 	list_for_each_entry_safe(it, tmp, &hba->rpmbs, node) {
226 		list_del(&it->node);
227 		device_unregister(&it->dev);
228 	}
229 
230 	return ret;
231 }
232 
233 /* UFS RPMB remove handler */
234 void ufs_rpmb_remove(struct ufs_hba *hba)
235 {
236 	struct ufs_rpmb_dev *ufs_rpmb, *tmp;
237 
238 	if (list_empty(&hba->rpmbs))
239 		return;
240 
241 	/* Remove all registered RPMB devices */
242 	list_for_each_entry_safe(ufs_rpmb, tmp, &hba->rpmbs, node) {
243 		dev_info(hba->dev, "Removing UFS RPMB region %d\n", ufs_rpmb->region_id);
244 		/* Remove from list first */
245 		list_del(&ufs_rpmb->node);
246 		/* Unregister device */
247 		device_unregister(&ufs_rpmb->dev);
248 	}
249 
250 	dev_info(hba->dev, "All UFS RPMB devices unregistered\n");
251 }
252 
253 MODULE_LICENSE("GPL v2");
254 MODULE_DESCRIPTION("OP-TEE UFS RPMB driver");
255