xref: /optee_os/core/drivers/tzc400.c (revision 51ac0e23b5c2b3c84469a0de79c9f027a46d5747)
1 /*
2  * Copyright (c) 2015, Linaro Limited
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright notice,
9  * this list of conditions and the following disclaimer.
10  *
11  * 2. Redistributions in binary form must reproduce the above copyright notice,
12  * this list of conditions and the following disclaimer in the documentation
13  * and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
19  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25  * POSSIBILITY OF SUCH DAMAGE.
26  */
27  /*
28  * Copyright (c) 2014, ARM Limited and Contributors. All rights reserved.
29  *
30  * Redistribution and use in source and binary forms, with or without
31  * modification, are permitted provided that the following conditions are met:
32  *
33  * Redistributions of source code must retain the above copyright notice, this
34  * list of conditions and the following disclaimer.
35  *
36  * Redistributions in binary form must reproduce the above copyright notice,
37  * this list of conditions and the following disclaimer in the documentation
38  * and/or other materials provided with the distribution.
39  *
40  * Neither the name of ARM nor the names of its contributors may be used
41  * to endorse or promote products derived from this software without specific
42  * prior written permission.
43  *
44  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
45  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
46  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
47  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
48  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
49  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
50  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
51  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
52  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
53  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
54  * POSSIBILITY OF SUCH DAMAGE.
55  */
56 
57 #include <assert.h>
58 #include <drivers/tzc400.h>
59 #include <io.h>
60 #include <kernel/panic.h>
61 #include <stddef.h>
62 #include <trace.h>
63 #include <util.h>
64 
65 /*
66  * Implementation defined values used to validate inputs later.
67  * Filters : max of 4 ; 0 to 3
68  * Regions : max of 9 ; 0 to 8
69  * Address width : Values between 32 to 64
70  */
71 struct tzc_instance {
72 	vaddr_t base;
73 	uint8_t addr_width;
74 	uint8_t num_filters;
75 	uint8_t num_regions;
76 };
77 
78 static struct tzc_instance tzc;
79 
80 
81 static uint32_t tzc_read_build_config(vaddr_t base)
82 {
83 	return read32(base + BUILD_CONFIG_OFF);
84 }
85 
86 static uint32_t tzc_read_gate_keeper(vaddr_t base)
87 {
88 	return read32(base + GATE_KEEPER_OFF);
89 }
90 
91 static void tzc_write_gate_keeper(vaddr_t base, uint32_t val)
92 {
93 	write32(val, base + GATE_KEEPER_OFF);
94 }
95 
96 static void tzc_write_action(vaddr_t base, enum tzc_action action)
97 {
98 	write32(action, base + ACTION_OFF);
99 }
100 
101 static void tzc_write_region_base_low(vaddr_t base, uint32_t region,
102 				      uint32_t val)
103 {
104 	write32(val, base + REGION_BASE_LOW_OFF +
105 		REGION_NUM_OFF(region));
106 }
107 
108 static void tzc_write_region_base_high(vaddr_t base, uint32_t region,
109 				       uint32_t val)
110 {
111 	write32(val, base + REGION_BASE_HIGH_OFF +
112 		REGION_NUM_OFF(region));
113 }
114 
115 static void tzc_write_region_top_low(vaddr_t base, uint32_t region,
116 				     uint32_t val)
117 {
118 	write32(val, base + REGION_TOP_LOW_OFF +
119 		REGION_NUM_OFF(region));
120 }
121 
122 static void tzc_write_region_top_high(vaddr_t base, uint32_t region,
123 				      uint32_t val)
124 {
125 	write32(val, base + REGION_TOP_HIGH_OFF +
126 		REGION_NUM_OFF(region));
127 }
128 
129 static void tzc_write_region_attributes(vaddr_t base, uint32_t region,
130 					uint32_t val)
131 {
132 	write32(val, base + REGION_ATTRIBUTES_OFF +
133 		REGION_NUM_OFF(region));
134 }
135 
136 static void tzc_write_region_id_access(vaddr_t base, uint32_t region,
137 				       uint32_t val)
138 {
139 	write32(val, base + REGION_ID_ACCESS_OFF +
140 		REGION_NUM_OFF(region));
141 }
142 
143 static uint32_t tzc_read_component_id(vaddr_t base)
144 {
145 	uint32_t id;
146 
147 	id = read8(base + CID0_OFF);
148 	id |= SHIFT_U32(read8(base + CID1_OFF), 8);
149 	id |= SHIFT_U32(read8(base + CID2_OFF), 16);
150 	id |= SHIFT_U32(read8(base + CID3_OFF), 24);
151 
152 	return id;
153 }
154 
155 static uint32_t tzc_get_gate_keeper(vaddr_t base, uint8_t filter)
156 {
157 	uint32_t tmp;
158 
159 	tmp = (tzc_read_gate_keeper(base) >> GATE_KEEPER_OS_SHIFT) &
160 		GATE_KEEPER_OS_MASK;
161 
162 	return (tmp >> filter) & GATE_KEEPER_FILTER_MASK;
163 }
164 
165 /* This function is not MP safe. */
166 static void tzc_set_gate_keeper(vaddr_t base, uint8_t filter, uint32_t val)
167 {
168 	uint32_t tmp;
169 
170 	/* Upper half is current state. Lower half is requested state. */
171 	tmp = (tzc_read_gate_keeper(base) >> GATE_KEEPER_OS_SHIFT) &
172 		GATE_KEEPER_OS_MASK;
173 
174 	if (val)
175 		tmp |=  (1 << filter);
176 	else
177 		tmp &= ~(1 << filter);
178 
179 	tzc_write_gate_keeper(base, (tmp & GATE_KEEPER_OR_MASK) <<
180 			      GATE_KEEPER_OR_SHIFT);
181 
182 	/* Wait here until we see the change reflected in the TZC status. */
183 	while (((tzc_read_gate_keeper(base) >> GATE_KEEPER_OS_SHIFT) &
184 		GATE_KEEPER_OS_MASK) != tmp)
185 		;
186 }
187 
188 
189 void tzc_init(vaddr_t base)
190 {
191 	uint32_t tzc_id, tzc_build;
192 
193 	assert(base);
194 	tzc.base = base;
195 
196 	/*
197 	 * We expect to see a tzc400. Check component ID. The TZC-400 TRM shows
198 	 * component ID is expected to be "0xB105F00D".
199 	 */
200 	tzc_id = tzc_read_component_id(tzc.base);
201 	if (tzc_id != TZC400_COMPONENT_ID) {
202 		EMSG("TZC : Wrong device ID (0x%x).\n", tzc_id);
203 		panic();
204 	}
205 
206 	/* Save values we will use later. */
207 	tzc_build = tzc_read_build_config(tzc.base);
208 	tzc.num_filters = ((tzc_build >> BUILD_CONFIG_NF_SHIFT) &
209 			   BUILD_CONFIG_NF_MASK) + 1;
210 	tzc.addr_width  = ((tzc_build >> BUILD_CONFIG_AW_SHIFT) &
211 			   BUILD_CONFIG_AW_MASK) + 1;
212 	tzc.num_regions = ((tzc_build >> BUILD_CONFIG_NR_SHIFT) &
213 			   BUILD_CONFIG_NR_MASK) + 1;
214 }
215 
216 static uint32_t addr_low(vaddr_t addr)
217 {
218 	return (uint32_t)addr;
219 }
220 
221 static uint32_t addr_high(vaddr_t addr __unused)
222 {
223 #if (UINTPTR_MAX == UINT64_MAX)
224 	return (addr >> 32);
225 #else
226 	return 0;
227 #endif
228 }
229 
230 
231 /*
232  * `tzc_configure_region` is used to program regions into the TrustZone
233  * controller. A region can be associated with more than one filter. The
234  * associated filters are passed in as a bitmap (bit0 = filter0).
235  * NOTE:
236  * The region 0 covers the whole address space and is enabled on all filters,
237  * this cannot be changed. It is, however, possible to change some region 0
238  * permissions.
239  */
240 void tzc_configure_region(uint32_t filters,
241 			  uint8_t  region,
242 			  vaddr_t  region_base,
243 			  vaddr_t  region_top,
244 			  enum tzc_region_attributes sec_attr,
245 			  uint32_t ns_device_access)
246 {
247 	assert(tzc.base);
248 
249 	/* Do range checks on filters and regions. */
250 	assert(((filters >> tzc.num_filters) == 0) &&
251 	       (region < tzc.num_regions));
252 
253 	/*
254 	 * Do address range check based on TZC configuration. A 64bit address is
255 	 * the max and expected case.
256 	 */
257 #if (UINTPTR_MAX == UINT64_MAX)
258 	assert(((region_top <= (UINT64_MAX >> (64 - tzc.addr_width))) &&
259 		(region_base < region_top)));
260 #endif
261 	/* region_base and (region_top + 1) must be 4KB aligned */
262 	assert(((region_base | (region_top + 1)) & (4096 - 1)) == 0);
263 
264 	assert(sec_attr <= TZC_REGION_S_RDWR);
265 
266 	/*
267 	 * Inputs look ok, start programming registers.
268 	 * All the address registers are 32 bits wide and have a LOW and HIGH
269 	 * component used to construct a up to a 64bit address.
270 	 */
271 	tzc_write_region_base_low(tzc.base, region,
272 				  addr_low(region_base));
273 	tzc_write_region_base_high(tzc.base, region,
274 				   addr_high(region_base));
275 
276 	tzc_write_region_top_low(tzc.base, region,
277 				addr_low(region_top));
278 	tzc_write_region_top_high(tzc.base, region,
279 				addr_high(region_top));
280 
281 	/* Assign the region to a filter and set secure attributes */
282 	tzc_write_region_attributes(tzc.base, region,
283 		(sec_attr << REG_ATTR_SEC_SHIFT) | filters);
284 
285 	/*
286 	 * Specify which non-secure devices have permission to access this
287 	 * region.
288 	 */
289 	tzc_write_region_id_access(tzc.base, region, ns_device_access);
290 }
291 
292 
293 void tzc_set_action(enum tzc_action action)
294 {
295 	assert(tzc.base);
296 
297 	/*
298 	 * - Currently no handler is provided to trap an error via interrupt
299 	 *   or exception.
300 	 * - The interrupt action has not been tested.
301 	 */
302 	tzc_write_action(tzc.base, action);
303 }
304 
305 
306 void tzc_enable_filters(void)
307 {
308 	uint32_t state;
309 	uint32_t filter;
310 
311 	assert(tzc.base);
312 
313 	for (filter = 0; filter < tzc.num_filters; filter++) {
314 		state = tzc_get_gate_keeper(tzc.base, filter);
315 		if (state) {
316 			/*
317 			 * The TZC filter is already configured. Changing the
318 			 * programmer's view in an active system can cause
319 			 * unpredictable behavior therefore panic for now rather
320 			 * than try to determine whether this is safe in this
321 			 * instance. See:
322 			 * http://infocenter.arm.com/help/index.jsp?\
323 			 * topic=/com.arm.doc.ddi0504c/CJHHECBF.html
324 			 */
325 			EMSG("TZC : Filter %d Gatekeeper already enabled.\n",
326 				filter);
327 			panic();
328 		}
329 		tzc_set_gate_keeper(tzc.base, filter, 1);
330 	}
331 }
332 
333 
334 void tzc_disable_filters(void)
335 {
336 	uint32_t filter;
337 
338 	assert(tzc.base);
339 
340 	/*
341 	 * We don't do the same state check as above as the Gatekeepers are
342 	 * disabled after reset.
343 	 */
344 	for (filter = 0; filter < tzc.num_filters; filter++)
345 		tzc_set_gate_keeper(tzc.base, filter, 0);
346 }
347 
348 #if TRACE_LEVEL >= TRACE_DEBUG
349 
350 static uint32_t tzc_read_region_attributes(vaddr_t base, uint32_t region)
351 {
352 	return read32(base + REGION_ATTRIBUTES_OFF + REGION_NUM_OFF(region));
353 }
354 
355 static uint32_t tzc_read_region_base_low(vaddr_t base, uint32_t region)
356 {
357 	return read32(base + REGION_BASE_LOW_OFF + REGION_NUM_OFF(region));
358 }
359 
360 static uint32_t tzc_read_region_base_high(vaddr_t base, uint32_t region)
361 {
362 	return read32(base + REGION_BASE_HIGH_OFF + REGION_NUM_OFF(region));
363 }
364 
365 static uint32_t tzc_read_region_top_low(vaddr_t base, uint32_t region)
366 {
367 	return read32(base + REGION_TOP_LOW_OFF + REGION_NUM_OFF(region));
368 }
369 
370 static uint32_t tzc_read_region_top_high(vaddr_t base, uint32_t region)
371 {
372 	return read32(base + REGION_TOP_HIGH_OFF + REGION_NUM_OFF(region));
373 }
374 
375 #define	REGION_MAX		8
376 static const __maybe_unused char * const tzc_attr_msg[] = {
377 	"TZC_REGION_S_NONE",
378 	"TZC_REGION_S_RD",
379 	"TZC_REGION_S_WR",
380 	"TZC_REGION_S_RDWR"
381 };
382 
383 void tzc_dump_state(void)
384 {
385 	uint32_t n;
386 	uint32_t temp_32reg, temp_32reg_h;
387 
388 	DMSG("enter");
389 	for (n = 0; n <= REGION_MAX; n++) {
390 		temp_32reg = tzc_read_region_attributes(tzc.base, n);
391 		if (!(temp_32reg & REG_ATTR_F_EN_MASK))
392 			continue;
393 
394 		DMSG("\n");
395 		DMSG("region %d", n);
396 		temp_32reg = tzc_read_region_base_low(tzc.base, n);
397 		temp_32reg_h = tzc_read_region_base_high(tzc.base, n);
398 		DMSG("region_base: 0x%08x%08x", temp_32reg_h, temp_32reg);
399 		temp_32reg = tzc_read_region_top_low(tzc.base, n);
400 		temp_32reg_h = tzc_read_region_top_high(tzc.base, n);
401 		DMSG("region_top: 0x%08x%08x", temp_32reg_h, temp_32reg);
402 		temp_32reg = tzc_read_region_attributes(tzc.base, n);
403 		DMSG("secure rw: %s",
404 		     tzc_attr_msg[temp_32reg >> REG_ATTR_SEC_SHIFT]);
405 		if (temp_32reg & (1 << 0))
406 			DMSG("filter 0 enable");
407 		if (temp_32reg & (1 << 1))
408 			DMSG("filter 1 enable");
409 		if (temp_32reg & (1 << 2))
410 			DMSG("filter 2 enable");
411 		if (temp_32reg & (1 << 3))
412 			DMSG("filter 3 enable");
413 	}
414 	DMSG("exit");
415 }
416 
417 #endif /* CFG_TRACE_LEVEL >= TRACE_DEBUG */
418