1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Texas Instruments' K3 Secure proxy Driver
4  *
5  * Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/
6  *	Lokesh Vutla <lokeshvutla@ti.com>
7  */
8 
9 #include <common.h>
10 #include <asm/io.h>
11 #include <linux/types.h>
12 #include <linux/bitops.h>
13 #include <linux/soc/ti/k3-sec-proxy.h>
14 #include <dm.h>
15 #include <mailbox-uclass.h>
16 
17 DECLARE_GLOBAL_DATA_PTR;
18 
19 /* SEC PROXY RT THREAD STATUS */
20 #define RT_THREAD_STATUS			0x0
21 #define RT_THREAD_THRESHOLD			0x4
22 #define RT_THREAD_STATUS_ERROR_SHIFT		31
23 #define RT_THREAD_STATUS_ERROR_MASK		BIT(31)
24 #define RT_THREAD_STATUS_CUR_CNT_SHIFT		0
25 #define RT_THREAD_STATUS_CUR_CNT_MASK		GENMASK(7, 0)
26 
27 /* SEC PROXY SCFG THREAD CTRL */
28 #define SCFG_THREAD_CTRL			0x1000
29 #define SCFG_THREAD_CTRL_DIR_SHIFT		31
30 #define SCFG_THREAD_CTRL_DIR_MASK		BIT(31)
31 
32 #define SEC_PROXY_THREAD(base, x)		((base) + (0x1000 * (x)))
33 #define THREAD_IS_RX				1
34 #define THREAD_IS_TX				0
35 
36 /**
37  * struct k3_sec_proxy_desc - Description of secure proxy integration.
38  * @thread_count:	Number of Threads.
39  * @max_msg_size:	Message size in bytes.
40  * @data_start_offset:	Offset of the First data register of the thread
41  * @data_end_offset:	Offset of the Last data register of the thread
42  * @valid_threads:	List of Valid threads that the processor can access
43  * @num_valid_threads:	Number of valid threads.
44  */
45 struct k3_sec_proxy_desc {
46 	u16 thread_count;
47 	u16 max_msg_size;
48 	u16 data_start_offset;
49 	u16 data_end_offset;
50 	const u32 *valid_threads;
51 	u32 num_valid_threads;
52 };
53 
54 /**
55  * struct k3_sec_proxy_thread - Description of a secure proxy Thread
56  * @id:		Thread ID
57  * @data:	Thread Data path region for target
58  * @scfg:	Secure Config Region for Thread
59  * @rt:		RealTime Region for Thread
60  * @rx_buf:	Receive buffer data, max message size.
61  */
62 struct k3_sec_proxy_thread {
63 	u32 id;
64 	void __iomem *data;
65 	void __iomem *scfg;
66 	void __iomem *rt;
67 	u32 *rx_buf;
68 };
69 
70 /**
71  * struct k3_sec_proxy_mbox - Description of a Secure Proxy Instance
72  * @chan:		Mailbox Channel
73  * @desc:		Description of the SoC integration
74  * @chans:		Array for valid thread instances
75  * @target_data:	Secure Proxy region for Target Data
76  * @scfg:		Secure Proxy Region for Secure configuration.
77  * @rt:			Secure proxy Region for Real Time Region.
78  */
79 struct k3_sec_proxy_mbox {
80 	struct mbox_chan chan;
81 	struct k3_sec_proxy_desc *desc;
82 	struct k3_sec_proxy_thread *chans;
83 	phys_addr_t target_data;
84 	phys_addr_t scfg;
85 	phys_addr_t rt;
86 };
87 
88 static inline u32 sp_readl(void __iomem *addr, unsigned int offset)
89 {
90 	return readl(addr + offset);
91 }
92 
93 static inline void sp_writel(void __iomem *addr, unsigned int offset, u32 data)
94 {
95 	writel(data, addr + offset);
96 }
97 
98 /**
99  * k3_sec_proxy_of_xlate() - Translation of phandle to channel
100  * @chan:	Mailbox channel
101  * @args:	Phandle Pointer
102  *
103  * Translates the phandle args and fills up the Mailbox channel from client.
104  * Return: 0 if all goes good, else return corresponding error message.
105  */
106 static int k3_sec_proxy_of_xlate(struct mbox_chan *chan,
107 				 struct ofnode_phandle_args *args)
108 {
109 	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
110 	int ind, i;
111 
112 	debug("%s(chan=%p)\n", __func__, chan);
113 
114 	if (args->args_count != 1) {
115 		debug("Invaild args_count: %d\n", args->args_count);
116 		return -EINVAL;
117 	}
118 	ind = args->args[0];
119 
120 	for (i = 0; i < spm->desc->num_valid_threads; i++)
121 		if (spm->chans[i].id == ind) {
122 			chan->id = ind;
123 			chan->con_priv = &spm->chans[i];
124 			return 0;
125 		}
126 
127 	dev_err(chan->dev, "%s: Invalid Thread ID %d\n", __func__, ind);
128 	return -ENOENT;
129 }
130 
131 /**
132  * k3_sec_proxy_request() - Request for mailbox channel
133  * @chan:	Channel Pointer
134  */
135 static int k3_sec_proxy_request(struct mbox_chan *chan)
136 {
137 	debug("%s(chan=%p)\n", __func__, chan);
138 
139 	return 0;
140 }
141 
142 /**
143  * k3_sec_proxy_free() - Free the mailbox channel
144  * @chan:	Channel Pointer
145  */
146 static int k3_sec_proxy_free(struct mbox_chan *chan)
147 {
148 	debug("%s(chan=%p)\n", __func__, chan);
149 
150 	return 0;
151 }
152 
153 /**
154  * k3_sec_proxy_verify_thread() - Verify thread status before
155  *				  sending/receiving data.
156  * @spt:	pointer to secure proxy thread description
157  * @dir:	Direction of the thread
158  *
159  * Return: 0 if all goes good, else appropriate error message.
160  */
161 static inline int k3_sec_proxy_verify_thread(struct k3_sec_proxy_thread *spt,
162 					     u8 dir)
163 {
164 	/* Check for any errors already available */
165 	if (sp_readl(spt->rt, RT_THREAD_STATUS) &
166 	    RT_THREAD_STATUS_ERROR_MASK) {
167 		printf("%s: Thread %d is corrupted, cannot send data.\n",
168 		       __func__, spt->id);
169 		return -EINVAL;
170 	}
171 
172 	/* Make sure thread is configured for right direction */
173 	if ((sp_readl(spt->scfg, SCFG_THREAD_CTRL)
174 	    & SCFG_THREAD_CTRL_DIR_MASK) >> SCFG_THREAD_CTRL_DIR_SHIFT != dir) {
175 		if (dir)
176 			printf("%s: Trying to receive data on tx Thread %d\n",
177 			       __func__, spt->id);
178 		else
179 			printf("%s: Trying to send data on rx Thread %d\n",
180 			       __func__, spt->id);
181 		return -EINVAL;
182 	}
183 
184 	/* Check the message queue before sending/receiving data */
185 	if (!(sp_readl(spt->rt, RT_THREAD_STATUS) &
186 	      RT_THREAD_STATUS_CUR_CNT_MASK))
187 		return -ENODATA;
188 
189 	return 0;
190 }
191 
192 /**
193  * k3_sec_proxy_send() - Send data via mailbox channel
194  * @chan:	Channel Pointer
195  * @data:	Pointer to k3_sec_proxy_msg
196  *
197  * Return: 0 if all goes good, else appropriate error message.
198  */
199 static int k3_sec_proxy_send(struct mbox_chan *chan, const void *data)
200 {
201 	const struct k3_sec_proxy_msg *msg = (struct k3_sec_proxy_msg *)data;
202 	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
203 	struct k3_sec_proxy_thread *spt = chan->con_priv;
204 	int num_words, trail_bytes, ret;
205 	void __iomem *data_reg;
206 	u32 *word_data;
207 
208 	debug("%s(chan=%p, data=%p)\n", __func__, chan, data);
209 
210 	ret = k3_sec_proxy_verify_thread(spt, THREAD_IS_TX);
211 	if (ret) {
212 		dev_err(dev, "%s: Thread%d verification failed. ret = %d\n",
213 			__func__, spt->id, ret);
214 		return ret;
215 	}
216 
217 	/* Check the message size. */
218 	if (msg->len > spm->desc->max_msg_size) {
219 		printf("%s: Thread %ld message length %zu > max msg size %d\n",
220 		       __func__, chan->id, msg->len, spm->desc->max_msg_size);
221 		return -EINVAL;
222 	}
223 
224 	/* Send the message */
225 	data_reg = spt->data + spm->desc->data_start_offset;
226 	for (num_words = msg->len / sizeof(u32), word_data = (u32 *)msg->buf;
227 	     num_words;
228 	     num_words--, data_reg += sizeof(u32), word_data++)
229 		writel(*word_data, data_reg);
230 
231 	trail_bytes = msg->len % sizeof(u32);
232 	if (trail_bytes) {
233 		u32 data_trail = *word_data;
234 
235 		/* Ensure all unused data is 0 */
236 		data_trail &= 0xFFFFFFFF >> (8 * (sizeof(u32) - trail_bytes));
237 		writel(data_trail, data_reg);
238 		data_reg++;
239 	}
240 
241 	/*
242 	 * 'data_reg' indicates next register to write. If we did not already
243 	 * write on tx complete reg(last reg), we must do so for transmit
244 	 */
245 	if (data_reg <= (spt->data + spm->desc->data_end_offset))
246 		sp_writel(spt->data, spm->desc->data_end_offset, 0);
247 
248 	debug("%s: Message successfully sent on thread %ld\n",
249 	      __func__, chan->id);
250 
251 	return 0;
252 }
253 
254 /**
255  * k3_sec_proxy_recv() - Receive data via mailbox channel
256  * @chan:	Channel Pointer
257  * @data:	Pointer to k3_sec_proxy_msg
258  *
259  * Return: 0 if all goes good, else appropriate error message.
260  */
261 static int k3_sec_proxy_recv(struct mbox_chan *chan, void *data)
262 {
263 	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
264 	struct k3_sec_proxy_thread *spt = chan->con_priv;
265 	struct k3_sec_proxy_msg *msg = data;
266 	void __iomem *data_reg;
267 	int num_words, ret;
268 	u32 *word_data;
269 
270 	debug("%s(chan=%p, data=%p)\n", __func__, chan, data);
271 
272 	ret = k3_sec_proxy_verify_thread(spt, THREAD_IS_RX);
273 	if (ret)
274 		return ret;
275 
276 	msg->len = spm->desc->max_msg_size;
277 	msg->buf = spt->rx_buf;
278 	data_reg = spt->data + spm->desc->data_start_offset;
279 	word_data = spt->rx_buf;
280 	for (num_words = spm->desc->max_msg_size / sizeof(u32);
281 	     num_words;
282 	     num_words--, data_reg += sizeof(u32), word_data++)
283 		*word_data = readl(data_reg);
284 
285 	debug("%s: Message successfully received from thread %ld\n",
286 	      __func__, chan->id);
287 
288 	return 0;
289 }
290 
291 struct mbox_ops k3_sec_proxy_mbox_ops = {
292 	.of_xlate = k3_sec_proxy_of_xlate,
293 	.request = k3_sec_proxy_request,
294 	.free = k3_sec_proxy_free,
295 	.send = k3_sec_proxy_send,
296 	.recv = k3_sec_proxy_recv,
297 };
298 
299 /**
300  * k3_sec_proxy_of_to_priv() - generate private data from device tree
301  * @dev:	corresponding k3 secure proxy device
302  * @spm:	pointer to driver specific private data
303  *
304  * Return: 0 if all went ok, else corresponding error message.
305  */
306 static int k3_sec_proxy_of_to_priv(struct udevice *dev,
307 				   struct k3_sec_proxy_mbox *spm)
308 {
309 	const void *blob = gd->fdt_blob;
310 
311 	if (!blob) {
312 		debug("'%s' no dt?\n", dev->name);
313 		return -ENODEV;
314 	}
315 
316 	spm->target_data = devfdt_get_addr_name(dev, "target_data");
317 	if (spm->target_data == FDT_ADDR_T_NONE) {
318 		dev_err(dev, "No reg property for target data base\n");
319 		return -EINVAL;
320 	}
321 
322 	spm->scfg = devfdt_get_addr_name(dev, "scfg");
323 	if (spm->rt == FDT_ADDR_T_NONE) {
324 		dev_err(dev, "No reg property for Secure Cfg base\n");
325 		return -EINVAL;
326 	}
327 
328 	spm->rt = devfdt_get_addr_name(dev, "rt");
329 	if (spm->rt == FDT_ADDR_T_NONE) {
330 		dev_err(dev, "No reg property for Real Time Cfg base\n");
331 		return -EINVAL;
332 	}
333 
334 	return 0;
335 }
336 
337 /**
338  * k3_sec_proxy_thread_setup - Initialize the parameters for all valid threads
339  * @spm:	Mailbox instance for which threads needs to be initialized
340  *
341  * Return: 0 if all went ok, else corresponding error message
342  */
343 static int k3_sec_proxy_thread_setup(struct k3_sec_proxy_mbox *spm)
344 {
345 	struct k3_sec_proxy_thread *spt;
346 	int i, ind;
347 
348 	for (i = 0; i < spm->desc->num_valid_threads; i++) {
349 		spt = &spm->chans[i];
350 		ind = spm->desc->valid_threads[i];
351 		spt->id = ind;
352 		spt->data = (void *)SEC_PROXY_THREAD(spm->target_data, ind);
353 		spt->scfg = (void *)SEC_PROXY_THREAD(spm->scfg, ind);
354 		spt->rt = (void *)SEC_PROXY_THREAD(spm->rt, ind);
355 		spt->rx_buf = calloc(1, spm->desc->max_msg_size);
356 		if (!spt->rx_buf)
357 			return -ENOMEM;
358 	}
359 
360 	return 0;
361 }
362 
363 /**
364  * k3_sec_proxy_probe() - Basic probe
365  * @dev:	corresponding mailbox device
366  *
367  * Return: 0 if all went ok, else corresponding error message
368  */
369 static int k3_sec_proxy_probe(struct udevice *dev)
370 {
371 	struct k3_sec_proxy_mbox *spm = dev_get_priv(dev);
372 	int ret;
373 
374 	debug("%s(dev=%p)\n", __func__, dev);
375 
376 	ret = k3_sec_proxy_of_to_priv(dev, spm);
377 	if (ret)
378 		return ret;
379 
380 	spm->desc = (void *)dev_get_driver_data(dev);
381 	spm->chans = calloc(spm->desc->num_valid_threads,
382 			    sizeof(struct k3_sec_proxy_thread));
383 	if (!spm->chans)
384 		return -ENOMEM;
385 
386 	ret = k3_sec_proxy_thread_setup(spm);
387 	if (ret) {
388 		debug("%s: secure proxy thread setup failed\n", __func__);
389 		return ret;
390 	}
391 
392 	return 0;
393 }
394 
395 static int k3_sec_proxy_remove(struct udevice *dev)
396 {
397 	struct k3_sec_proxy_mbox *spm = dev_get_priv(dev);
398 
399 	debug("%s(dev=%p)\n", __func__, dev);
400 
401 	free(spm->chans);
402 
403 	return 0;
404 }
405 
406 /*
407  * Thread ID #4: ROM request
408  * Thread ID #5: ROM response, SYSFW notify
409  * Thread ID #6: SYSFW request response
410  * Thread ID #7: SYSFW request high priority
411  * Thread ID #8: SYSFW request low priority
412  * Thread ID #9: SYSFW notify response
413  */
414 static const u32 am6x_valid_threads[] = { 4, 5, 6, 7, 8, 9, 11, 13 };
415 
416 static const struct k3_sec_proxy_desc am654_desc = {
417 	.thread_count = 90,
418 	.max_msg_size = 60,
419 	.data_start_offset = 0x4,
420 	.data_end_offset = 0x3C,
421 	.valid_threads = am6x_valid_threads,
422 	.num_valid_threads = ARRAY_SIZE(am6x_valid_threads),
423 };
424 
425 static const struct udevice_id k3_sec_proxy_ids[] = {
426 	{ .compatible = "ti,am654-secure-proxy", .data = (ulong)&am654_desc},
427 	{ }
428 };
429 
430 U_BOOT_DRIVER(k3_sec_proxy) = {
431 	.name = "k3-secure-proxy",
432 	.id = UCLASS_MAILBOX,
433 	.of_match = k3_sec_proxy_ids,
434 	.probe = k3_sec_proxy_probe,
435 	.remove = k3_sec_proxy_remove,
436 	.priv_auto_alloc_size = sizeof(struct k3_sec_proxy_mbox),
437 	.ops = &k3_sec_proxy_mbox_ops,
438 };
439