xref: /rk3399_rockchip-uboot/drivers/rng/rockchip_rng.c (revision b37fed8ca09be3e699ec1ed20a2cbe01bab40f3c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2020 Fuzhou Rockchip Electronics Co., Ltd
4  */
5 #include <asm/arch-rockchip/hardware.h>
6 #include <asm/io.h>
7 #include <common.h>
8 #include <dm.h>
9 #include <linux/iopoll.h>
10 #include <linux/string.h>
11 #include <rng.h>
12 
13 #define RK_HW_RNG_MAX 32
14 
15 #define _SBF(s, v)	((v) << (s))
16 
17 /* start of CRYPTO V1 register define */
18 #define CRYPTO_V1_CTRL				0x0008
19 #define CRYPTO_V1_RNG_START			BIT(8)
20 #define CRYPTO_V1_RNG_FLUSH			BIT(9)
21 
22 #define CRYPTO_V1_TRNG_CTRL			0x0200
23 #define CRYPTO_V1_OSC_ENABLE			BIT(16)
24 #define CRYPTO_V1_TRNG_SAMPLE_PERIOD(x)		(x)
25 
26 #define CRYPTO_V1_TRNG_DOUT_0			0x0204
27 /* end of CRYPTO V1 register define */
28 
29 /* start of CRYPTO V2 register define */
30 #define CRYPTO_V2_RNG_CTL			0x0400
31 #define CRYPTO_V2_RNG_64_BIT_LEN		_SBF(4, 0x00)
32 #define CRYPTO_V2_RNG_128_BIT_LEN		_SBF(4, 0x01)
33 #define CRYPTO_V2_RNG_192_BIT_LEN		_SBF(4, 0x02)
34 #define CRYPTO_V2_RNG_256_BIT_LEN		_SBF(4, 0x03)
35 #define CRYPTO_V2_RNG_FATESY_SOC_RING		_SBF(2, 0x00)
36 #define CRYPTO_V2_RNG_SLOWER_SOC_RING_0		_SBF(2, 0x01)
37 #define CRYPTO_V2_RNG_SLOWER_SOC_RING_1		_SBF(2, 0x02)
38 #define CRYPTO_V2_RNG_SLOWEST_SOC_RING		_SBF(2, 0x03)
39 #define CRYPTO_V2_RNG_ENABLE			BIT(1)
40 #define CRYPTO_V2_RNG_START			BIT(0)
41 #define CRYPTO_V2_RNG_SAMPLE_CNT		0x0404
42 #define CRYPTO_V2_RNG_DOUT_0			0x0410
43 /* end of CRYPTO V2 register define */
44 
45 /* start of TRNG V1 register define */
46 #define TRNG_V1_CTRL				0x0000
47 #define TRNG_V1_CTRL_NOP			_SBF(0, 0x00)
48 #define TRNG_V1_CTRL_RAND			_SBF(0, 0x01)
49 #define TRNG_V1_CTRL_SEED			_SBF(0, 0x02)
50 
51 #define TRNG_V1_MODE				0x0008
52 #define TRNG_V1_MODE_128_BIT			_SBF(3, 0x00)
53 #define TRNG_V1_MODE_256_BIT			_SBF(3, 0x01)
54 
55 #define TRNG_V1_IE				0x0010
56 #define TRNG_V1_IE_GLBL_EN			BIT(31)
57 #define TRNG_V1_IE_SEED_DONE_EN			BIT(1)
58 #define TRNG_V1_IE_RAND_RDY_EN			BIT(0)
59 
60 #define TRNG_V1_ISTAT				0x0014
61 #define TRNG_V1_ISTAT_RAND_RDY			BIT(0)
62 
63 /* RAND0 ~ RAND7 */
64 #define TRNG_V1_RAND0				0x0020
65 #define TRNG_V1_RAND7				0x003C
66 
67 #define TRNG_V1_AUTO_RQSTS			0x0060
68 
69 #define TRNG_V1_VERSION				0x00F0
70 #define TRNG_v1_VERSION_CODE			0x46BC
71 /* end of TRNG V1 register define */
72 
73 /* start of RKRNG register define */
74 #define RKRNG_CTRL				0x0010
75 #define RKRNG_CTRL_INST_REQ			BIT(0)
76 #define RKRNG_CTRL_RESEED_REQ			BIT(1)
77 #define RKRNG_CTRL_TEST_REQ			BIT(2)
78 #define RKRNG_CTRL_SW_DRNG_REQ			BIT(3)
79 #define RKRNG_CTRL_SW_TRNG_REQ			BIT(4)
80 
81 #define RKRNG_STATE				0x0014
82 #define RKRNG_STATE_INST_ACK			BIT(0)
83 #define RKRNG_STATE_RESEED_ACK			BIT(1)
84 #define RKRNG_STATE_TEST_ACK			BIT(2)
85 #define RKRNG_STATE_SW_DRNG_ACK			BIT(3)
86 #define RKRNG_STATE_SW_TRNG_ACK			BIT(4)
87 
88 /* DRNG_DATA_0 ~ DNG_DATA_7 */
89 #define RKRNG_DRNG_DATA_0			0x0070
90 #define RKRNG_DRNG_DATA_7			0x008C
91 
92 /* end of RKRNG register define */
93 
94 #define RK_RNG_TIME_OUT	50000  /* max 50ms */
95 
96 #define trng_write(pdata, pos, val)	writel(val, (pdata)->base + (pos))
97 #define trng_read(pdata, pos)		readl((pdata)->base + (pos))
98 
99 struct rk_rng_soc_data {
100 	int (*rk_rng_init)(struct udevice *dev);
101 	int (*rk_rng_read)(struct udevice *dev, void *data, size_t len);
102 };
103 
104 struct rk_rng_platdata {
105 	fdt_addr_t base;
106 	struct rk_rng_soc_data *soc_data;
107 };
108 
109 static int rk_rng_read_regs(fdt_addr_t addr, void *buf, size_t size)
110 {
111 	u32 count = RK_HW_RNG_MAX / sizeof(u32);
112 	u32 reg, tmp_len;
113 
114 	if (size > RK_HW_RNG_MAX)
115 		return -EINVAL;
116 
117 	while (size && count) {
118 		reg = readl(addr);
119 		tmp_len = min(size, sizeof(u32));
120 		memcpy(buf, &reg, tmp_len);
121 		addr += sizeof(u32);
122 		buf += tmp_len;
123 		size -= tmp_len;
124 		count--;
125 	}
126 
127 	return 0;
128 }
129 
130 static int cryptov1_rng_read(struct udevice *dev, void *data, size_t len)
131 {
132 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
133 	u32 reg = 0;
134 	int retval;
135 
136 	if (len > RK_HW_RNG_MAX)
137 		return -EINVAL;
138 
139 	/* enable osc_ring to get entropy, sample period is set as 100 */
140 	writel(CRYPTO_V1_OSC_ENABLE | CRYPTO_V1_TRNG_SAMPLE_PERIOD(100),
141 	       pdata->base + CRYPTO_V1_TRNG_CTRL);
142 
143 	rk_clrsetreg(pdata->base + CRYPTO_V1_CTRL, CRYPTO_V1_RNG_START,
144 		     CRYPTO_V1_RNG_START);
145 
146 	retval = readl_poll_timeout(pdata->base + CRYPTO_V1_CTRL, reg,
147 				    !(reg & CRYPTO_V1_RNG_START),
148 				    RK_RNG_TIME_OUT);
149 	if (retval)
150 		goto exit;
151 
152 	rk_rng_read_regs(pdata->base + CRYPTO_V1_TRNG_DOUT_0, data, len);
153 
154 exit:
155 	/* close TRNG */
156 	rk_clrreg(pdata->base + CRYPTO_V1_CTRL, CRYPTO_V1_RNG_START);
157 
158 	return 0;
159 }
160 
161 static int cryptov2_rng_read(struct udevice *dev, void *data, size_t len)
162 {
163 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
164 	u32 reg = 0;
165 	int retval;
166 
167 	if (len > RK_HW_RNG_MAX)
168 		return -EINVAL;
169 
170 	/* enable osc_ring to get entropy, sample period is set as 100 */
171 	writel(100, pdata->base + CRYPTO_V2_RNG_SAMPLE_CNT);
172 
173 	reg |= CRYPTO_V2_RNG_256_BIT_LEN;
174 	reg |= CRYPTO_V2_RNG_SLOWER_SOC_RING_0;
175 	reg |= CRYPTO_V2_RNG_ENABLE;
176 	reg |= CRYPTO_V2_RNG_START;
177 
178 	rk_clrsetreg(pdata->base + CRYPTO_V2_RNG_CTL, 0xffff, reg);
179 
180 	retval = readl_poll_timeout(pdata->base + CRYPTO_V2_RNG_CTL, reg,
181 				    !(reg & CRYPTO_V2_RNG_START),
182 				    RK_RNG_TIME_OUT);
183 	if (retval)
184 		goto exit;
185 
186 	rk_rng_read_regs(pdata->base + CRYPTO_V2_RNG_DOUT_0, data, len);
187 
188 exit:
189 	/* close TRNG */
190 	rk_clrreg(pdata->base + CRYPTO_V2_RNG_CTL, 0xffff);
191 
192 	return retval;
193 }
194 
195 static int trngv1_init(struct udevice *dev)
196 {
197 	u32 status, version;
198 	u32 auto_reseed_cnt = 1000;
199 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
200 
201 	version = trng_read(pdata, TRNG_V1_VERSION);
202 	if (version != TRNG_v1_VERSION_CODE) {
203 		printf("wrong trng version, expected = %08x, actual = %08x",
204 		       TRNG_V1_VERSION, version);
205 		return -EFAULT;
206 	}
207 
208 	/* wait in case of RND_RDY triggered at firs power on */
209 	readl_poll_timeout(pdata->base + TRNG_V1_ISTAT, status,
210 			   (status & TRNG_V1_ISTAT_RAND_RDY),
211 			   RK_RNG_TIME_OUT);
212 
213 	/* clear RAND_RDY flag for first power on */
214 	trng_write(pdata, TRNG_V1_ISTAT, status);
215 
216 	/* auto reseed after (auto_reseed_cnt * 16) byte rand generate */
217 	trng_write(pdata, TRNG_V1_AUTO_RQSTS, auto_reseed_cnt);
218 
219 	return 0;
220 }
221 
222 static int trngv1_rng_read(struct udevice *dev, void *data, size_t len)
223 {
224 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
225 	u32 reg = 0;
226 	int retval;
227 
228 	if (len > RK_HW_RNG_MAX)
229 		return -EINVAL;
230 
231 	trng_write(pdata, TRNG_V1_MODE, TRNG_V1_MODE_256_BIT);
232 	trng_write(pdata, TRNG_V1_CTRL, TRNG_V1_CTRL_RAND);
233 
234 	retval = readl_poll_timeout(pdata->base + TRNG_V1_ISTAT, reg,
235 				    (reg & TRNG_V1_ISTAT_RAND_RDY),
236 				    RK_RNG_TIME_OUT);
237 	/* clear ISTAT */
238 	trng_write(pdata, TRNG_V1_ISTAT, reg);
239 
240 	if (retval)
241 		goto exit;
242 
243 	rk_rng_read_regs(pdata->base + TRNG_V1_RAND0, data, len);
244 
245 exit:
246 	/* close TRNG */
247 	trng_write(pdata, TRNG_V1_CTRL, TRNG_V1_CTRL_NOP);
248 
249 	return retval;
250 }
251 
252 static int rkrng_init(struct udevice *dev)
253 {
254 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
255 	u32 reg = 0;
256 
257 	rk_clrreg(pdata->base + RKRNG_CTRL, 0xffff);
258 
259 	reg = trng_read(pdata, RKRNG_STATE);
260 	trng_write(pdata, RKRNG_STATE, reg);
261 
262 	return 0;
263 }
264 
265 static int rkrng_rng_read(struct udevice *dev, void *data, size_t len)
266 {
267 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
268 	u32 reg = 0;
269 	int retval;
270 
271 	if (len > RK_HW_RNG_MAX)
272 		return -EINVAL;
273 
274 	reg = RKRNG_CTRL_SW_DRNG_REQ;
275 
276 	rk_clrsetreg(pdata->base + RKRNG_CTRL, 0xffff, reg);
277 
278 	retval = readl_poll_timeout(pdata->base + RKRNG_STATE, reg,
279 				    (reg & RKRNG_STATE_SW_DRNG_ACK),
280 				    RK_RNG_TIME_OUT);
281 	if (retval)
282 		goto exit;
283 
284 	trng_write(pdata, RKRNG_STATE, reg);
285 
286 	rk_rng_read_regs(pdata->base + RKRNG_DRNG_DATA_0, data, len);
287 
288 exit:
289 	/* close TRNG */
290 	rk_clrreg(pdata->base + RKRNG_CTRL, 0xffff);
291 
292 	return retval;
293 }
294 
295 static int rockchip_rng_read(struct udevice *dev, void *data, size_t len)
296 {
297 	unsigned char *buf = data;
298 	unsigned int i;
299 	int ret = -EIO;
300 
301 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
302 
303 	if (!len)
304 		return 0;
305 
306 	if (!pdata->soc_data || !pdata->soc_data->rk_rng_read)
307 		return -EINVAL;
308 
309 	for (i = 0; i < len / RK_HW_RNG_MAX; i++, buf += RK_HW_RNG_MAX) {
310 		ret = pdata->soc_data->rk_rng_read(dev, buf, RK_HW_RNG_MAX);
311 		if (ret)
312 			goto exit;
313 	}
314 
315 	if (len % RK_HW_RNG_MAX)
316 		ret = pdata->soc_data->rk_rng_read(dev, buf,
317 						   len % RK_HW_RNG_MAX);
318 
319 exit:
320 	return ret;
321 }
322 
323 static int rockchip_rng_ofdata_to_platdata(struct udevice *dev)
324 {
325 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
326 
327 	memset(pdata, 0x00, sizeof(*pdata));
328 
329 	pdata->base = (fdt_addr_t)dev_read_addr_ptr(dev);
330 	if (!pdata->base)
331 		return -ENOMEM;
332 
333 	return 0;
334 }
335 
336 static int rockchip_rng_probe(struct udevice *dev)
337 {
338 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
339 	int ret = 0;
340 
341 	pdata->soc_data = (struct rk_rng_soc_data *)dev_get_driver_data(dev);
342 
343 	if (pdata->soc_data->rk_rng_init)
344 		ret = pdata->soc_data->rk_rng_init(dev);
345 
346 	return ret;
347 }
348 
349 static const struct rk_rng_soc_data cryptov1_soc_data = {
350 	.rk_rng_read = cryptov1_rng_read,
351 };
352 
353 static const struct rk_rng_soc_data cryptov2_soc_data = {
354 	.rk_rng_read = cryptov2_rng_read,
355 };
356 
357 static const struct rk_rng_soc_data trngv1_soc_data = {
358 	.rk_rng_init = trngv1_init,
359 	.rk_rng_read = trngv1_rng_read,
360 };
361 
362 static const struct rk_rng_soc_data rkrng_soc_data = {
363 	.rk_rng_init = rkrng_init,
364 	.rk_rng_read = rkrng_rng_read,
365 };
366 
367 static const struct dm_rng_ops rockchip_rng_ops = {
368 	.read = rockchip_rng_read,
369 };
370 
371 static const struct udevice_id rockchip_rng_match[] = {
372 	{
373 		.compatible = "rockchip,cryptov1-rng",
374 		.data = (ulong)&cryptov1_soc_data,
375 	},
376 	{
377 		.compatible = "rockchip,cryptov2-rng",
378 		.data = (ulong)&cryptov2_soc_data,
379 	},
380 	{
381 		.compatible = "rockchip,trngv1",
382 		.data = (ulong)&trngv1_soc_data,
383 	},
384 	{
385 		.compatible = "rockchip,rkrng",
386 		.data = (ulong)&rkrng_soc_data,
387 	},
388 	{},
389 };
390 
391 U_BOOT_DRIVER(rockchip_rng) = {
392 	.name = "rockchip-rng",
393 	.id = UCLASS_RNG,
394 	.of_match = rockchip_rng_match,
395 	.ops = &rockchip_rng_ops,
396 	.probe = rockchip_rng_probe,
397 	.ofdata_to_platdata = rockchip_rng_ofdata_to_platdata,
398 	.priv_auto_alloc_size = sizeof(struct rk_rng_platdata),
399 };
400