xref: /OK3568_Linux_fs/u-boot/drivers/rng/rockchip_rng.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2020 Fuzhou Rockchip Electronics Co., Ltd
4  */
5 #include <common.h>
6 #include <clk-uclass.h>
7 #include <dm.h>
8 #include <rng.h>
9 #include <asm/arch-rockchip/hardware.h>
10 #include <asm/io.h>
11 #include <linux/iopoll.h>
12 #include <linux/string.h>
13 
14 #define RK_HW_RNG_MAX 32
15 
16 #define _SBF(s, v)	((v) << (s))
17 
18 /* start of CRYPTO V1 register define */
19 #define CRYPTO_V1_CTRL				0x0008
20 #define CRYPTO_V1_RNG_START			BIT(8)
21 #define CRYPTO_V1_RNG_FLUSH			BIT(9)
22 
23 #define CRYPTO_V1_TRNG_CTRL			0x0200
24 #define CRYPTO_V1_OSC_ENABLE			BIT(16)
25 #define CRYPTO_V1_TRNG_SAMPLE_PERIOD(x)		(x)
26 
27 #define CRYPTO_V1_TRNG_DOUT_0			0x0204
28 /* end of CRYPTO V1 register define */
29 
30 /* start of CRYPTO V2 register define */
31 #define CRYPTO_V2_RNG_CTL			0x0400
32 #define CRYPTO_V2_RNG_64_BIT_LEN		_SBF(4, 0x00)
33 #define CRYPTO_V2_RNG_128_BIT_LEN		_SBF(4, 0x01)
34 #define CRYPTO_V2_RNG_192_BIT_LEN		_SBF(4, 0x02)
35 #define CRYPTO_V2_RNG_256_BIT_LEN		_SBF(4, 0x03)
36 #define CRYPTO_V2_RNG_FATESY_SOC_RING		_SBF(2, 0x00)
37 #define CRYPTO_V2_RNG_SLOWER_SOC_RING_0		_SBF(2, 0x01)
38 #define CRYPTO_V2_RNG_SLOWER_SOC_RING_1		_SBF(2, 0x02)
39 #define CRYPTO_V2_RNG_SLOWEST_SOC_RING		_SBF(2, 0x03)
40 #define CRYPTO_V2_RNG_ENABLE			BIT(1)
41 #define CRYPTO_V2_RNG_START			BIT(0)
42 #define CRYPTO_V2_RNG_SAMPLE_CNT		0x0404
43 #define CRYPTO_V2_RNG_DOUT_0			0x0410
44 /* end of CRYPTO V2 register define */
45 
46 /* start of TRNG V1 register define */
47 #define TRNG_V1_CTRL				0x0000
48 #define TRNG_V1_CTRL_NOP			_SBF(0, 0x00)
49 #define TRNG_V1_CTRL_RAND			_SBF(0, 0x01)
50 #define TRNG_V1_CTRL_SEED			_SBF(0, 0x02)
51 
52 #define TRNG_V1_MODE				0x0008
53 #define TRNG_V1_MODE_128_BIT			_SBF(3, 0x00)
54 #define TRNG_V1_MODE_256_BIT			_SBF(3, 0x01)
55 
56 #define TRNG_V1_IE				0x0010
57 #define TRNG_V1_IE_GLBL_EN			BIT(31)
58 #define TRNG_V1_IE_SEED_DONE_EN			BIT(1)
59 #define TRNG_V1_IE_RAND_RDY_EN			BIT(0)
60 
61 #define TRNG_V1_ISTAT				0x0014
62 #define TRNG_V1_ISTAT_RAND_RDY			BIT(0)
63 
64 /* RAND0 ~ RAND7 */
65 #define TRNG_V1_RAND0				0x0020
66 #define TRNG_V1_RAND7				0x003C
67 
68 #define TRNG_V1_AUTO_RQSTS			0x0060
69 
70 #define TRNG_V1_VERSION				0x00F0
71 #define TRNG_v1_VERSION_CODE			0x46BC
72 /* end of TRNG V1 register define */
73 
74 /* start of RKRNG register define */
75 #define RKRNG_CTRL				0x0010
76 #define RKRNG_CTRL_INST_REQ			BIT(0)
77 #define RKRNG_CTRL_RESEED_REQ			BIT(1)
78 #define RKRNG_CTRL_TEST_REQ			BIT(2)
79 #define RKRNG_CTRL_SW_DRNG_REQ			BIT(3)
80 #define RKRNG_CTRL_SW_TRNG_REQ			BIT(4)
81 
82 #define RKRNG_STATE				0x0014
83 #define RKRNG_STATE_INST_ACK			BIT(0)
84 #define RKRNG_STATE_RESEED_ACK			BIT(1)
85 #define RKRNG_STATE_TEST_ACK			BIT(2)
86 #define RKRNG_STATE_SW_DRNG_ACK			BIT(3)
87 #define RKRNG_STATE_SW_TRNG_ACK			BIT(4)
88 
89 /* DRNG_DATA_0 ~ DNG_DATA_7 */
90 #define RKRNG_DRNG_DATA_0			0x0070
91 #define RKRNG_DRNG_DATA_7			0x008C
92 
93 /* end of RKRNG register define */
94 
95 #define RK_RNG_TIME_OUT	50000  /* max 50ms */
96 
97 #define trng_write(pdata, pos, val)	writel(val, (pdata)->base + (pos))
98 #define trng_read(pdata, pos)		readl((pdata)->base + (pos))
99 
100 struct rk_rng_soc_data {
101 	int (*rk_rng_init)(struct udevice *dev);
102 	int (*rk_rng_read)(struct udevice *dev, void *data, size_t len);
103 };
104 
105 struct rk_rng_platdata {
106 	fdt_addr_t base;
107 	struct rk_rng_soc_data *soc_data;
108 	struct clk hclk;
109 };
110 
rk_rng_do_enable_clk(struct udevice * dev,int enable)111 static int rk_rng_do_enable_clk(struct udevice *dev, int enable)
112 {
113 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
114 	int ret;
115 
116 	if (!pdata->hclk.dev)
117 		return 0;
118 
119 	ret = enable ? clk_enable(&pdata->hclk) : clk_disable(&pdata->hclk);
120 	if (ret == -ENOSYS || !ret)
121 		return 0;
122 
123 	printf("rk rng: failed to %s clk, ret=%d\n",
124 	       enable ? "enable" : "disable", ret);
125 
126 	return ret;
127 }
128 
rk_rng_enable_clk(struct udevice * dev)129 static int rk_rng_enable_clk(struct udevice *dev)
130 {
131 	return rk_rng_do_enable_clk(dev, 1);
132 }
133 
rk_rng_disable_clk(struct udevice * dev)134 static int rk_rng_disable_clk(struct udevice *dev)
135 {
136 	return rk_rng_do_enable_clk(dev, 0);
137 }
138 
rk_rng_read_regs(fdt_addr_t addr,void * buf,size_t size)139 static int rk_rng_read_regs(fdt_addr_t addr, void *buf, size_t size)
140 {
141 	u32 count = RK_HW_RNG_MAX / sizeof(u32);
142 	u32 reg, tmp_len;
143 
144 	if (size > RK_HW_RNG_MAX)
145 		return -EINVAL;
146 
147 	while (size && count) {
148 		reg = readl(addr);
149 		tmp_len = min(size, sizeof(u32));
150 		memcpy(buf, &reg, tmp_len);
151 		addr += sizeof(u32);
152 		buf += tmp_len;
153 		size -= tmp_len;
154 		count--;
155 	}
156 
157 	return 0;
158 }
159 
cryptov1_rng_read(struct udevice * dev,void * data,size_t len)160 static int cryptov1_rng_read(struct udevice *dev, void *data, size_t len)
161 {
162 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
163 	u32 reg = 0;
164 	int retval;
165 
166 	if (len > RK_HW_RNG_MAX)
167 		return -EINVAL;
168 
169 	/* enable osc_ring to get entropy, sample period is set as 100 */
170 	writel(CRYPTO_V1_OSC_ENABLE | CRYPTO_V1_TRNG_SAMPLE_PERIOD(100),
171 	       pdata->base + CRYPTO_V1_TRNG_CTRL);
172 
173 	rk_clrsetreg(pdata->base + CRYPTO_V1_CTRL, CRYPTO_V1_RNG_START,
174 		     CRYPTO_V1_RNG_START);
175 
176 	retval = readl_poll_timeout(pdata->base + CRYPTO_V1_CTRL, reg,
177 				    !(reg & CRYPTO_V1_RNG_START),
178 				    RK_RNG_TIME_OUT);
179 	if (retval)
180 		goto exit;
181 
182 	rk_rng_read_regs(pdata->base + CRYPTO_V1_TRNG_DOUT_0, data, len);
183 
184 exit:
185 	/* close TRNG */
186 	rk_clrreg(pdata->base + CRYPTO_V1_CTRL, CRYPTO_V1_RNG_START);
187 
188 	return 0;
189 }
190 
cryptov2_rng_read(struct udevice * dev,void * data,size_t len)191 static int cryptov2_rng_read(struct udevice *dev, void *data, size_t len)
192 {
193 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
194 	u32 reg = 0;
195 	int retval;
196 
197 	if (len > RK_HW_RNG_MAX)
198 		return -EINVAL;
199 
200 	/* enable osc_ring to get entropy, sample period is set as 100 */
201 	writel(100, pdata->base + CRYPTO_V2_RNG_SAMPLE_CNT);
202 
203 	reg |= CRYPTO_V2_RNG_256_BIT_LEN;
204 	reg |= CRYPTO_V2_RNG_SLOWER_SOC_RING_0;
205 	reg |= CRYPTO_V2_RNG_ENABLE;
206 	reg |= CRYPTO_V2_RNG_START;
207 
208 	rk_clrsetreg(pdata->base + CRYPTO_V2_RNG_CTL, 0xffff, reg);
209 
210 	retval = readl_poll_timeout(pdata->base + CRYPTO_V2_RNG_CTL, reg,
211 				    !(reg & CRYPTO_V2_RNG_START),
212 				    RK_RNG_TIME_OUT);
213 	if (retval)
214 		goto exit;
215 
216 	rk_rng_read_regs(pdata->base + CRYPTO_V2_RNG_DOUT_0, data, len);
217 
218 exit:
219 	/* close TRNG */
220 	rk_clrreg(pdata->base + CRYPTO_V2_RNG_CTL, 0xffff);
221 
222 	return retval;
223 }
224 
trngv1_init(struct udevice * dev)225 static int trngv1_init(struct udevice *dev)
226 {
227 	u32 status, version;
228 	u32 auto_reseed_cnt = 1000;
229 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
230 
231 	version = trng_read(pdata, TRNG_V1_VERSION);
232 	if (version != TRNG_v1_VERSION_CODE) {
233 		printf("wrong trng version, expected = %08x, actual = %08x",
234 		       TRNG_V1_VERSION, version);
235 		return -EFAULT;
236 	}
237 
238 	/* wait in case of RND_RDY triggered at firs power on */
239 	readl_poll_timeout(pdata->base + TRNG_V1_ISTAT, status,
240 			   (status & TRNG_V1_ISTAT_RAND_RDY),
241 			   RK_RNG_TIME_OUT);
242 
243 	/* clear RAND_RDY flag for first power on */
244 	trng_write(pdata, TRNG_V1_ISTAT, status);
245 
246 	/* auto reseed after (auto_reseed_cnt * 16) byte rand generate */
247 	trng_write(pdata, TRNG_V1_AUTO_RQSTS, auto_reseed_cnt);
248 
249 	return 0;
250 }
251 
trngv1_rng_read(struct udevice * dev,void * data,size_t len)252 static int trngv1_rng_read(struct udevice *dev, void *data, size_t len)
253 {
254 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
255 	u32 reg = 0;
256 	int retval;
257 
258 	if (len > RK_HW_RNG_MAX)
259 		return -EINVAL;
260 
261 	trng_write(pdata, TRNG_V1_MODE, TRNG_V1_MODE_256_BIT);
262 	trng_write(pdata, TRNG_V1_CTRL, TRNG_V1_CTRL_RAND);
263 
264 	retval = readl_poll_timeout(pdata->base + TRNG_V1_ISTAT, reg,
265 				    (reg & TRNG_V1_ISTAT_RAND_RDY),
266 				    RK_RNG_TIME_OUT);
267 	/* clear ISTAT */
268 	trng_write(pdata, TRNG_V1_ISTAT, reg);
269 
270 	if (retval)
271 		goto exit;
272 
273 	rk_rng_read_regs(pdata->base + TRNG_V1_RAND0, data, len);
274 
275 exit:
276 	/* close TRNG */
277 	trng_write(pdata, TRNG_V1_CTRL, TRNG_V1_CTRL_NOP);
278 
279 	return retval;
280 }
281 
rkrng_init(struct udevice * dev)282 static int rkrng_init(struct udevice *dev)
283 {
284 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
285 	u32 reg = 0;
286 
287 	rk_clrreg(pdata->base + RKRNG_CTRL, 0xffff);
288 
289 	reg = trng_read(pdata, RKRNG_STATE);
290 	trng_write(pdata, RKRNG_STATE, reg);
291 
292 	return 0;
293 }
294 
rkrng_rng_read(struct udevice * dev,void * data,size_t len)295 static int rkrng_rng_read(struct udevice *dev, void *data, size_t len)
296 {
297 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
298 	u32 reg = 0;
299 	int retval;
300 
301 	if (len > RK_HW_RNG_MAX)
302 		return -EINVAL;
303 
304 	rk_rng_enable_clk(dev);
305 
306 	reg = RKRNG_CTRL_SW_DRNG_REQ;
307 
308 	rk_clrsetreg(pdata->base + RKRNG_CTRL, 0xffff, reg);
309 
310 	retval = readl_poll_timeout(pdata->base + RKRNG_STATE, reg,
311 				    (reg & RKRNG_STATE_SW_DRNG_ACK),
312 				    RK_RNG_TIME_OUT);
313 	if (retval)
314 		goto exit;
315 
316 	trng_write(pdata, RKRNG_STATE, reg);
317 
318 	rk_rng_read_regs(pdata->base + RKRNG_DRNG_DATA_0, data, len);
319 
320 exit:
321 	/* close TRNG */
322 	rk_clrreg(pdata->base + RKRNG_CTRL, 0xffff);
323 
324 	rk_rng_disable_clk(dev);
325 
326 	return retval;
327 }
328 
rockchip_rng_read(struct udevice * dev,void * data,size_t len)329 static int rockchip_rng_read(struct udevice *dev, void *data, size_t len)
330 {
331 	unsigned char *buf = data;
332 	unsigned int i;
333 	int ret = -EIO;
334 
335 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
336 
337 	if (!len)
338 		return 0;
339 
340 	if (!pdata->soc_data || !pdata->soc_data->rk_rng_read)
341 		return -EINVAL;
342 
343 	for (i = 0; i < len / RK_HW_RNG_MAX; i++, buf += RK_HW_RNG_MAX) {
344 		ret = pdata->soc_data->rk_rng_read(dev, buf, RK_HW_RNG_MAX);
345 		if (ret)
346 			goto exit;
347 	}
348 
349 	if (len % RK_HW_RNG_MAX)
350 		ret = pdata->soc_data->rk_rng_read(dev, buf,
351 						   len % RK_HW_RNG_MAX);
352 
353 exit:
354 	return ret;
355 }
356 
rockchip_rng_ofdata_to_platdata(struct udevice * dev)357 static int rockchip_rng_ofdata_to_platdata(struct udevice *dev)
358 {
359 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
360 
361 	memset(pdata, 0x00, sizeof(*pdata));
362 
363 	pdata->base = (fdt_addr_t)dev_read_addr_ptr(dev);
364 	if (!pdata->base)
365 		return -ENOMEM;
366 
367 	clk_get_by_index(dev, 0, &pdata->hclk);
368 
369 	return 0;
370 }
371 
rockchip_rng_probe(struct udevice * dev)372 static int rockchip_rng_probe(struct udevice *dev)
373 {
374 	struct rk_rng_platdata *pdata = dev_get_priv(dev);
375 	int ret = 0;
376 
377 	pdata->soc_data = (struct rk_rng_soc_data *)dev_get_driver_data(dev);
378 
379 	if (pdata->soc_data->rk_rng_init)
380 		ret = pdata->soc_data->rk_rng_init(dev);
381 
382 	return ret;
383 }
384 
385 static const struct rk_rng_soc_data cryptov1_soc_data = {
386 	.rk_rng_read = cryptov1_rng_read,
387 };
388 
389 static const struct rk_rng_soc_data cryptov2_soc_data = {
390 	.rk_rng_read = cryptov2_rng_read,
391 };
392 
393 static const struct rk_rng_soc_data trngv1_soc_data = {
394 	.rk_rng_init = trngv1_init,
395 	.rk_rng_read = trngv1_rng_read,
396 };
397 
398 static const struct rk_rng_soc_data rkrng_soc_data = {
399 	.rk_rng_init = rkrng_init,
400 	.rk_rng_read = rkrng_rng_read,
401 };
402 
403 static const struct dm_rng_ops rockchip_rng_ops = {
404 	.read = rockchip_rng_read,
405 };
406 
407 static const struct udevice_id rockchip_rng_match[] = {
408 	{
409 		.compatible = "rockchip,cryptov1-rng",
410 		.data = (ulong)&cryptov1_soc_data,
411 	},
412 	{
413 		.compatible = "rockchip,cryptov2-rng",
414 		.data = (ulong)&cryptov2_soc_data,
415 	},
416 	{
417 		.compatible = "rockchip,trngv1",
418 		.data = (ulong)&trngv1_soc_data,
419 	},
420 	{
421 		.compatible = "rockchip,rkrng",
422 		.data = (ulong)&rkrng_soc_data,
423 	},
424 	{},
425 };
426 
427 U_BOOT_DRIVER(rockchip_rng) = {
428 	.name = "rockchip-rng",
429 	.id = UCLASS_RNG,
430 	.of_match = rockchip_rng_match,
431 	.ops = &rockchip_rng_ops,
432 	.probe = rockchip_rng_probe,
433 	.ofdata_to_platdata = rockchip_rng_ofdata_to_platdata,
434 	.priv_auto_alloc_size = sizeof(struct rk_rng_platdata),
435 };
436