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 <log.h>
11 #include <malloc.h>
12 #include <asm/global_data.h>
13 #include <asm/io.h>
14 #include <dm/device_compat.h>
15 #include <linux/types.h>
16 #include <linux/bitops.h>
17 #include <linux/soc/ti/k3-sec-proxy.h>
18 #include <dm.h>
19 #include <mailbox-uclass.h>
20 
21 DECLARE_GLOBAL_DATA_PTR;
22 
23 /* SEC PROXY RT THREAD STATUS */
24 #define RT_THREAD_STATUS			0x0
25 #define RT_THREAD_THRESHOLD			0x4
26 #define RT_THREAD_STATUS_ERROR_SHIFT		31
27 #define RT_THREAD_STATUS_ERROR_MASK		BIT(31)
28 #define RT_THREAD_STATUS_CUR_CNT_SHIFT		0
29 #define RT_THREAD_STATUS_CUR_CNT_MASK		GENMASK(7, 0)
30 
31 /* SEC PROXY SCFG THREAD CTRL */
32 #define SCFG_THREAD_CTRL			0x1000
33 #define SCFG_THREAD_CTRL_DIR_SHIFT		31
34 #define SCFG_THREAD_CTRL_DIR_MASK		BIT(31)
35 
36 #define SEC_PROXY_THREAD(base, x)		((base) + (0x1000 * (x)))
37 #define THREAD_IS_RX				1
38 #define THREAD_IS_TX				0
39 
40 /**
41  * struct k3_sec_proxy_desc - Description of secure proxy integration.
42  * @thread_count:	Number of Threads.
43  * @max_msg_size:	Message size in bytes.
44  * @data_start_offset:	Offset of the First data register of the thread
45  * @data_end_offset:	Offset of the Last data register of the thread
46  * @valid_threads:	List of Valid threads that the processor can access
47  * @num_valid_threads:	Number of valid threads.
48  */
49 struct k3_sec_proxy_desc {
50 	u16 thread_count;
51 	u16 max_msg_size;
52 	u16 data_start_offset;
53 	u16 data_end_offset;
54 	const u32 *valid_threads;
55 	u32 num_valid_threads;
56 };
57 
58 /**
59  * struct k3_sec_proxy_thread - Description of a secure proxy Thread
60  * @id:		Thread ID
61  * @data:	Thread Data path region for target
62  * @scfg:	Secure Config Region for Thread
63  * @rt:		RealTime Region for Thread
64  * @rx_buf:	Receive buffer data, max message size.
65  */
66 struct k3_sec_proxy_thread {
67 	u32 id;
68 	void __iomem *data;
69 	void __iomem *scfg;
70 	void __iomem *rt;
71 	u32 *rx_buf;
72 };
73 
74 /**
75  * struct k3_sec_proxy_mbox - Description of a Secure Proxy Instance
76  * @chan:		Mailbox Channel
77  * @desc:		Description of the SoC integration
78  * @chans:		Array for valid thread instances
79  * @target_data:	Secure Proxy region for Target Data
80  * @scfg:		Secure Proxy Region for Secure configuration.
81  * @rt:			Secure proxy Region for Real Time Region.
82  */
83 struct k3_sec_proxy_mbox {
84 	struct mbox_chan chan;
85 	struct k3_sec_proxy_desc *desc;
86 	struct k3_sec_proxy_thread *chans;
87 	phys_addr_t target_data;
88 	phys_addr_t scfg;
89 	phys_addr_t rt;
90 };
91 
sp_readl(void __iomem * addr,unsigned int offset)92 static inline u32 sp_readl(void __iomem *addr, unsigned int offset)
93 {
94 	return readl(addr + offset);
95 }
96 
sp_writel(void __iomem * addr,unsigned int offset,u32 data)97 static inline void sp_writel(void __iomem *addr, unsigned int offset, u32 data)
98 {
99 	writel(data, addr + offset);
100 }
101 
102 /**
103  * k3_sec_proxy_of_xlate() - Translation of phandle to channel
104  * @chan:	Mailbox channel
105  * @args:	Phandle Pointer
106  *
107  * Translates the phandle args and fills up the Mailbox channel from client.
108  * Return: 0 if all goes good, else return corresponding error message.
109  */
k3_sec_proxy_of_xlate(struct mbox_chan * chan,struct ofnode_phandle_args * args)110 static int k3_sec_proxy_of_xlate(struct mbox_chan *chan,
111 				 struct ofnode_phandle_args *args)
112 {
113 	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
114 	int ind, i;
115 
116 	debug("%s(chan=%p)\n", __func__, chan);
117 
118 	if (args->args_count != 1) {
119 		debug("Invaild args_count: %d\n", args->args_count);
120 		return -EINVAL;
121 	}
122 	ind = args->args[0];
123 
124 	for (i = 0; i < spm->desc->num_valid_threads; i++)
125 		if (spm->chans[i].id == ind) {
126 			chan->id = ind;
127 			chan->con_priv = &spm->chans[i];
128 			return 0;
129 		}
130 
131 	dev_err(chan->dev, "%s: Invalid Thread ID %d\n", __func__, ind);
132 	return -ENOENT;
133 }
134 
135 /**
136  * k3_sec_proxy_request() - Request for mailbox channel
137  * @chan:	Channel Pointer
138  */
k3_sec_proxy_request(struct mbox_chan * chan)139 static int k3_sec_proxy_request(struct mbox_chan *chan)
140 {
141 	debug("%s(chan=%p)\n", __func__, chan);
142 
143 	return 0;
144 }
145 
146 /**
147  * k3_sec_proxy_free() - Free the mailbox channel
148  * @chan:	Channel Pointer
149  */
k3_sec_proxy_free(struct mbox_chan * chan)150 static int k3_sec_proxy_free(struct mbox_chan *chan)
151 {
152 	debug("%s(chan=%p)\n", __func__, chan);
153 
154 	return 0;
155 }
156 
157 /**
158  * k3_sec_proxy_verify_thread() - Verify thread status before
159  *				  sending/receiving data.
160  * @spt:	pointer to secure proxy thread description
161  * @dir:	Direction of the thread
162  *
163  * Return: 0 if all goes good, else appropriate error message.
164  */
k3_sec_proxy_verify_thread(struct k3_sec_proxy_thread * spt,u8 dir)165 static inline int k3_sec_proxy_verify_thread(struct k3_sec_proxy_thread *spt,
166 					     u8 dir)
167 {
168 	/* Check for any errors already available */
169 	if (sp_readl(spt->rt, RT_THREAD_STATUS) &
170 	    RT_THREAD_STATUS_ERROR_MASK) {
171 		printf("%s: Thread %d is corrupted, cannot send data.\n",
172 		       __func__, spt->id);
173 		return -EINVAL;
174 	}
175 
176 	/* Make sure thread is configured for right direction */
177 	if ((sp_readl(spt->scfg, SCFG_THREAD_CTRL)
178 	    & SCFG_THREAD_CTRL_DIR_MASK) >> SCFG_THREAD_CTRL_DIR_SHIFT != dir) {
179 		if (dir)
180 			printf("%s: Trying to receive data on tx Thread %d\n",
181 			       __func__, spt->id);
182 		else
183 			printf("%s: Trying to send data on rx Thread %d\n",
184 			       __func__, spt->id);
185 		return -EINVAL;
186 	}
187 
188 	/* Check the message queue before sending/receiving data */
189 	if (!(sp_readl(spt->rt, RT_THREAD_STATUS) &
190 	      RT_THREAD_STATUS_CUR_CNT_MASK))
191 		return -ENODATA;
192 
193 	return 0;
194 }
195 
196 /**
197  * k3_sec_proxy_send() - Send data via mailbox channel
198  * @chan:	Channel Pointer
199  * @data:	Pointer to k3_sec_proxy_msg
200  *
201  * Return: 0 if all goes good, else appropriate error message.
202  */
k3_sec_proxy_send(struct mbox_chan * chan,const void * data)203 static int k3_sec_proxy_send(struct mbox_chan *chan, const void *data)
204 {
205 	const struct k3_sec_proxy_msg *msg = (struct k3_sec_proxy_msg *)data;
206 	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
207 	struct k3_sec_proxy_thread *spt = chan->con_priv;
208 	int num_words, trail_bytes, ret;
209 	void __iomem *data_reg;
210 	u32 *word_data;
211 
212 	debug("%s(chan=%p, data=%p)\n", __func__, chan, data);
213 
214 	ret = k3_sec_proxy_verify_thread(spt, THREAD_IS_TX);
215 	if (ret) {
216 		dev_err(chan->dev,
217 			"%s: Thread%d verification failed. ret = %d\n",
218 			__func__, spt->id, ret);
219 		return ret;
220 	}
221 
222 	/* Check the message size. */
223 	if (msg->len > spm->desc->max_msg_size) {
224 		dev_err(chan->dev,
225 			"%s: Thread %ld message length %zu > max msg size %d\n",
226 		       __func__, chan->id, msg->len, spm->desc->max_msg_size);
227 		return -EINVAL;
228 	}
229 
230 	/* Send the message */
231 	data_reg = spt->data + spm->desc->data_start_offset;
232 	for (num_words = msg->len / sizeof(u32), word_data = (u32 *)msg->buf;
233 	     num_words;
234 	     num_words--, data_reg += sizeof(u32), word_data++)
235 		writel(*word_data, data_reg);
236 
237 	trail_bytes = msg->len % sizeof(u32);
238 	if (trail_bytes) {
239 		u32 data_trail = *word_data;
240 
241 		/* Ensure all unused data is 0 */
242 		data_trail &= 0xFFFFFFFF >> (8 * (sizeof(u32) - trail_bytes));
243 		writel(data_trail, data_reg);
244 		data_reg++;
245 	}
246 
247 	/*
248 	 * 'data_reg' indicates next register to write. If we did not already
249 	 * write on tx complete reg(last reg), we must do so for transmit
250 	 */
251 	if (data_reg <= (spt->data + spm->desc->data_end_offset))
252 		sp_writel(spt->data, spm->desc->data_end_offset, 0);
253 
254 	debug("%s: Message successfully sent on thread %ld\n",
255 	      __func__, chan->id);
256 
257 	return 0;
258 }
259 
260 /**
261  * k3_sec_proxy_recv() - Receive data via mailbox channel
262  * @chan:	Channel Pointer
263  * @data:	Pointer to k3_sec_proxy_msg
264  *
265  * Return: 0 if all goes good, else appropriate error message.
266  */
k3_sec_proxy_recv(struct mbox_chan * chan,void * data)267 static int k3_sec_proxy_recv(struct mbox_chan *chan, void *data)
268 {
269 	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
270 	struct k3_sec_proxy_thread *spt = chan->con_priv;
271 	struct k3_sec_proxy_msg *msg = data;
272 	void __iomem *data_reg;
273 	int num_words, ret;
274 	u32 *word_data;
275 
276 	debug("%s(chan=%p, data=%p)\n", __func__, chan, data);
277 
278 	ret = k3_sec_proxy_verify_thread(spt, THREAD_IS_RX);
279 	if (ret)
280 		return ret;
281 
282 	msg->len = spm->desc->max_msg_size;
283 	msg->buf = spt->rx_buf;
284 	data_reg = spt->data + spm->desc->data_start_offset;
285 	word_data = spt->rx_buf;
286 	for (num_words = spm->desc->max_msg_size / sizeof(u32);
287 	     num_words;
288 	     num_words--, data_reg += sizeof(u32), word_data++)
289 		*word_data = readl(data_reg);
290 
291 	debug("%s: Message successfully received from thread %ld\n",
292 	      __func__, chan->id);
293 
294 	return 0;
295 }
296 
297 struct mbox_ops k3_sec_proxy_mbox_ops = {
298 	.of_xlate = k3_sec_proxy_of_xlate,
299 	.request = k3_sec_proxy_request,
300 	.rfree = k3_sec_proxy_free,
301 	.send = k3_sec_proxy_send,
302 	.recv = k3_sec_proxy_recv,
303 };
304 
305 /**
306  * k3_sec_proxy_of_to_priv() - generate private data from device tree
307  * @dev:	corresponding k3 secure proxy device
308  * @spm:	pointer to driver specific private data
309  *
310  * Return: 0 if all went ok, else corresponding error message.
311  */
k3_sec_proxy_of_to_priv(struct udevice * dev,struct k3_sec_proxy_mbox * spm)312 static int k3_sec_proxy_of_to_priv(struct udevice *dev,
313 				   struct k3_sec_proxy_mbox *spm)
314 {
315 	const void *blob = gd->fdt_blob;
316 
317 	if (!blob) {
318 		debug("'%s' no dt?\n", dev->name);
319 		return -ENODEV;
320 	}
321 
322 	spm->target_data = devfdt_get_addr_name(dev, "target_data");
323 	if (spm->target_data == FDT_ADDR_T_NONE) {
324 		dev_err(dev, "No reg property for target data base\n");
325 		return -EINVAL;
326 	}
327 
328 	spm->scfg = devfdt_get_addr_name(dev, "scfg");
329 	if (spm->rt == FDT_ADDR_T_NONE) {
330 		dev_err(dev, "No reg property for Secure Cfg base\n");
331 		return -EINVAL;
332 	}
333 
334 	spm->rt = devfdt_get_addr_name(dev, "rt");
335 	if (spm->rt == FDT_ADDR_T_NONE) {
336 		dev_err(dev, "No reg property for Real Time Cfg base\n");
337 		return -EINVAL;
338 	}
339 
340 	return 0;
341 }
342 
343 /**
344  * k3_sec_proxy_thread_setup - Initialize the parameters for all valid threads
345  * @spm:	Mailbox instance for which threads needs to be initialized
346  *
347  * Return: 0 if all went ok, else corresponding error message
348  */
k3_sec_proxy_thread_setup(struct k3_sec_proxy_mbox * spm)349 static int k3_sec_proxy_thread_setup(struct k3_sec_proxy_mbox *spm)
350 {
351 	struct k3_sec_proxy_thread *spt;
352 	int i, ind;
353 
354 	for (i = 0; i < spm->desc->num_valid_threads; i++) {
355 		spt = &spm->chans[i];
356 		ind = spm->desc->valid_threads[i];
357 		spt->id = ind;
358 		spt->data = (void *)SEC_PROXY_THREAD(spm->target_data, ind);
359 		spt->scfg = (void *)SEC_PROXY_THREAD(spm->scfg, ind);
360 		spt->rt = (void *)SEC_PROXY_THREAD(spm->rt, ind);
361 		spt->rx_buf = calloc(1, spm->desc->max_msg_size);
362 		if (!spt->rx_buf)
363 			return -ENOMEM;
364 	}
365 
366 	return 0;
367 }
368 
369 /**
370  * k3_sec_proxy_probe() - Basic probe
371  * @dev:	corresponding mailbox device
372  *
373  * Return: 0 if all went ok, else corresponding error message
374  */
k3_sec_proxy_probe(struct udevice * dev)375 static int k3_sec_proxy_probe(struct udevice *dev)
376 {
377 	struct k3_sec_proxy_mbox *spm = dev_get_priv(dev);
378 	int ret;
379 
380 	debug("%s(dev=%p)\n", __func__, dev);
381 
382 	ret = k3_sec_proxy_of_to_priv(dev, spm);
383 	if (ret)
384 		return ret;
385 
386 	spm->desc = (void *)dev_get_driver_data(dev);
387 	spm->chans = calloc(spm->desc->num_valid_threads,
388 			    sizeof(struct k3_sec_proxy_thread));
389 	if (!spm->chans)
390 		return -ENOMEM;
391 
392 	ret = k3_sec_proxy_thread_setup(spm);
393 	if (ret) {
394 		debug("%s: secure proxy thread setup failed\n", __func__);
395 		return ret;
396 	}
397 
398 	return 0;
399 }
400 
k3_sec_proxy_remove(struct udevice * dev)401 static int k3_sec_proxy_remove(struct udevice *dev)
402 {
403 	struct k3_sec_proxy_mbox *spm = dev_get_priv(dev);
404 
405 	debug("%s(dev=%p)\n", __func__, dev);
406 
407 	free(spm->chans);
408 
409 	return 0;
410 }
411 
412 /*
413  * Thread ID #4: ROM request
414  * Thread ID #5: ROM response, SYSFW notify
415  * Thread ID #6: SYSFW request response
416  * Thread ID #7: SYSFW request high priority
417  * Thread ID #8: SYSFW request low priority
418  * Thread ID #9: SYSFW notify response
419  */
420 static const u32 am6x_valid_threads[] = { 4, 5, 6, 7, 8, 9, 11, 13 };
421 
422 static const struct k3_sec_proxy_desc am654_desc = {
423 	.thread_count = 90,
424 	.max_msg_size = 60,
425 	.data_start_offset = 0x4,
426 	.data_end_offset = 0x3C,
427 	.valid_threads = am6x_valid_threads,
428 	.num_valid_threads = ARRAY_SIZE(am6x_valid_threads),
429 };
430 
431 static const struct udevice_id k3_sec_proxy_ids[] = {
432 	{ .compatible = "ti,am654-secure-proxy", .data = (ulong)&am654_desc},
433 	{ }
434 };
435 
436 U_BOOT_DRIVER(k3_sec_proxy) = {
437 	.name = "k3-secure-proxy",
438 	.id = UCLASS_MAILBOX,
439 	.of_match = k3_sec_proxy_ids,
440 	.probe = k3_sec_proxy_probe,
441 	.remove = k3_sec_proxy_remove,
442 	.priv_auto	= sizeof(struct k3_sec_proxy_mbox),
443 	.ops = &k3_sec_proxy_mbox_ops,
444 };
445