1 /*
2  * Copyright (c) 2016-2021, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <stddef.h>
9 
10 #include <common/debug.h>
11 #include <drivers/arm/tzc400.h>
12 #include <lib/mmio.h>
13 #include <lib/utils_def.h>
14 
15 #include "tzc_common_private.h"
16 
17 /*
18  * Macros which will be used by common core functions.
19  */
20 #define TZC_400_REGION_BASE_LOW_0_OFFSET	U(0x100)
21 #define TZC_400_REGION_BASE_HIGH_0_OFFSET	U(0x104)
22 #define TZC_400_REGION_TOP_LOW_0_OFFSET		U(0x108)
23 #define TZC_400_REGION_TOP_HIGH_0_OFFSET	U(0x10c)
24 #define TZC_400_REGION_ATTR_0_OFFSET		U(0x110)
25 #define TZC_400_REGION_ID_ACCESS_0_OFFSET	U(0x114)
26 
27 /*
28  * Implementation defined values used to validate inputs later.
29  * Filters : max of 4 ; 0 to 3
30  * Regions : max of 9 ; 0 to 8
31  * Address width : Values between 32 to 64
32  */
33 typedef struct tzc400_instance {
34 	uintptr_t base;
35 	uint8_t addr_width;
36 	uint8_t num_filters;
37 	uint8_t num_regions;
38 } tzc400_instance_t;
39 
40 static tzc400_instance_t tzc400;
41 
_tzc400_read_build_config(uintptr_t base)42 static inline unsigned int _tzc400_read_build_config(uintptr_t base)
43 {
44 	return mmio_read_32(base + BUILD_CONFIG_OFF);
45 }
46 
_tzc400_read_gate_keeper(uintptr_t base)47 static inline unsigned int _tzc400_read_gate_keeper(uintptr_t base)
48 {
49 	return mmio_read_32(base + GATE_KEEPER_OFF);
50 }
51 
_tzc400_write_gate_keeper(uintptr_t base,unsigned int val)52 static inline void _tzc400_write_gate_keeper(uintptr_t base, unsigned int val)
53 {
54 	mmio_write_32(base + GATE_KEEPER_OFF, val);
55 }
56 
57 /*
58  * Get the open status information for all filter units.
59  */
60 #define get_gate_keeper_os(_base)	((_tzc400_read_gate_keeper(_base) >>  \
61 					GATE_KEEPER_OS_SHIFT) &		\
62 					GATE_KEEPER_OS_MASK)
63 
64 
65 /* Define common core functions used across different TZC peripherals. */
66 DEFINE_TZC_COMMON_WRITE_ACTION(400, 400)
67 DEFINE_TZC_COMMON_WRITE_REGION_BASE(400, 400)
68 DEFINE_TZC_COMMON_WRITE_REGION_TOP(400, 400)
69 DEFINE_TZC_COMMON_WRITE_REGION_ATTRIBUTES(400, 400)
70 DEFINE_TZC_COMMON_WRITE_REGION_ID_ACCESS(400, 400)
71 DEFINE_TZC_COMMON_UPDATE_FILTERS(400, 400)
72 DEFINE_TZC_COMMON_CONFIGURE_REGION0(400)
73 DEFINE_TZC_COMMON_CONFIGURE_REGION(400)
74 
_tzc400_clear_it(uintptr_t base,uint32_t filter)75 static void _tzc400_clear_it(uintptr_t base, uint32_t filter)
76 {
77 	mmio_write_32(base + INT_CLEAR, BIT_32(filter));
78 }
79 
_tzc400_get_int_by_filter(uintptr_t base,uint32_t filter)80 static uint32_t _tzc400_get_int_by_filter(uintptr_t base, uint32_t filter)
81 {
82 	return mmio_read_32(base + INT_STATUS) & BIT_32(filter);
83 }
84 
85 #if DEBUG
_tzc400_get_fail_address(uintptr_t base,uint32_t filter)86 static unsigned long _tzc400_get_fail_address(uintptr_t base, uint32_t filter)
87 {
88 	unsigned long fail_address;
89 
90 	fail_address = mmio_read_32(base + FAIL_ADDRESS_LOW_OFF +
91 				    (filter * FILTER_OFFSET));
92 #ifdef __aarch64__
93 	fail_address += (unsigned long)mmio_read_32(base + FAIL_ADDRESS_HIGH_OFF +
94 						    (filter * FILTER_OFFSET)) << 32;
95 #endif
96 
97 	return fail_address;
98 }
99 
_tzc400_get_fail_id(uintptr_t base,uint32_t filter)100 static uint32_t _tzc400_get_fail_id(uintptr_t base, uint32_t filter)
101 {
102 	return mmio_read_32(base + FAIL_ID + (filter * FILTER_OFFSET));
103 }
104 
_tzc400_get_fail_control(uintptr_t base,uint32_t filter)105 static uint32_t _tzc400_get_fail_control(uintptr_t base, uint32_t filter)
106 {
107 	return mmio_read_32(base + FAIL_CONTROL_OFF + (filter * FILTER_OFFSET));
108 }
109 
_tzc400_dump_fail_filter(uintptr_t base,uint32_t filter)110 static void _tzc400_dump_fail_filter(uintptr_t base, uint32_t filter)
111 {
112 	uint32_t control_fail;
113 	uint32_t fail_id;
114 	unsigned long address_fail;
115 
116 	address_fail = _tzc400_get_fail_address(base, filter);
117 	ERROR("Illegal access to 0x%lx:\n", address_fail);
118 
119 	fail_id = _tzc400_get_fail_id(base, filter);
120 	ERROR("\tFAIL_ID = 0x%x\n", fail_id);
121 
122 	control_fail = _tzc400_get_fail_control(base, filter);
123 	if (((control_fail & BIT_32(FAIL_CONTROL_NS_SHIFT)) >> FAIL_CONTROL_NS_SHIFT) ==
124 	    FAIL_CONTROL_NS_NONSECURE) {
125 		ERROR("\tNon-Secure\n");
126 	} else {
127 		ERROR("\tSecure\n");
128 	}
129 
130 	if (((control_fail & BIT_32(FAIL_CONTROL_PRIV_SHIFT)) >> FAIL_CONTROL_PRIV_SHIFT) ==
131 	    FAIL_CONTROL_PRIV_PRIV) {
132 		ERROR("\tPrivilege\n");
133 	} else {
134 		ERROR("\tUnprivilege\n");
135 	}
136 
137 	if (((control_fail & BIT_32(FAIL_CONTROL_DIR_SHIFT)) >> FAIL_CONTROL_DIR_SHIFT) ==
138 	    FAIL_CONTROL_DIR_WRITE) {
139 		ERROR("\tWrite\n");
140 	} else {
141 		ERROR("\tRead\n");
142 	}
143 }
144 #endif /* DEBUG */
145 
_tzc400_get_gate_keeper(uintptr_t base,unsigned int filter)146 static unsigned int _tzc400_get_gate_keeper(uintptr_t base,
147 				unsigned int filter)
148 {
149 	unsigned int open_status;
150 
151 	open_status = get_gate_keeper_os(base);
152 
153 	return (open_status >> filter) & GATE_KEEPER_FILTER_MASK;
154 }
155 
156 /* This function is not MP safe. */
_tzc400_set_gate_keeper(uintptr_t base,unsigned int filter,int val)157 static void _tzc400_set_gate_keeper(uintptr_t base,
158 				unsigned int filter,
159 				int val)
160 {
161 	unsigned int open_status;
162 
163 	/* Upper half is current state. Lower half is requested state. */
164 	open_status = get_gate_keeper_os(base);
165 
166 	if (val != 0)
167 		open_status |=  (1UL << filter);
168 	else
169 		open_status &= ~(1UL << filter);
170 
171 	_tzc400_write_gate_keeper(base, (open_status & GATE_KEEPER_OR_MASK) <<
172 			      GATE_KEEPER_OR_SHIFT);
173 
174 	/* Wait here until we see the change reflected in the TZC status. */
175 	while ((get_gate_keeper_os(base)) != open_status)
176 		;
177 }
178 
tzc400_set_action(unsigned int action)179 void tzc400_set_action(unsigned int action)
180 {
181 	assert(tzc400.base != 0U);
182 	assert(action <= TZC_ACTION_ERR_INT);
183 
184 	_tzc400_write_action(tzc400.base, action);
185 }
186 
tzc400_init(uintptr_t base)187 void tzc400_init(uintptr_t base)
188 {
189 #if DEBUG
190 	unsigned int tzc400_id;
191 #endif
192 	unsigned int tzc400_build;
193 
194 	assert(base != 0U);
195 	tzc400.base = base;
196 
197 #if DEBUG
198 	tzc400_id = _tzc_read_peripheral_id(base);
199 	if (tzc400_id != TZC_400_PERIPHERAL_ID) {
200 		ERROR("TZC-400 : Wrong device ID (0x%x).\n", tzc400_id);
201 		panic();
202 	}
203 #endif
204 
205 	/* Save values we will use later. */
206 	tzc400_build = _tzc400_read_build_config(tzc400.base);
207 	tzc400.num_filters = (uint8_t)((tzc400_build >> BUILD_CONFIG_NF_SHIFT) &
208 					BUILD_CONFIG_NF_MASK) + 1U;
209 	tzc400.addr_width  = (uint8_t)((tzc400_build >> BUILD_CONFIG_AW_SHIFT) &
210 					BUILD_CONFIG_AW_MASK) + 1U;
211 	tzc400.num_regions = (uint8_t)((tzc400_build >> BUILD_CONFIG_NR_SHIFT) &
212 					BUILD_CONFIG_NR_MASK) + 1U;
213 }
214 
215 /*
216  * `tzc400_configure_region0` is used to program region 0 into the TrustZone
217  * controller. Region 0 covers the whole address space that is not mapped
218  * to any other region, and is enabled on all filters; this cannot be
219  * changed. This function only changes the access permissions.
220  */
tzc400_configure_region0(unsigned int sec_attr,unsigned int ns_device_access)221 void tzc400_configure_region0(unsigned int sec_attr,
222 			   unsigned int ns_device_access)
223 {
224 	assert(tzc400.base != 0U);
225 	assert(sec_attr <= TZC_REGION_S_RDWR);
226 
227 	_tzc400_configure_region0(tzc400.base, sec_attr, ns_device_access);
228 }
229 
230 /*
231  * `tzc400_configure_region` is used to program regions into the TrustZone
232  * controller. A region can be associated with more than one filter. The
233  * associated filters are passed in as a bitmap (bit0 = filter0), except that
234  * the value TZC_400_REGION_ATTR_FILTER_BIT_ALL selects all filters, based on
235  * the value of tzc400.num_filters.
236  * NOTE:
237  * Region 0 is special; it is preferable to use tzc400_configure_region0
238  * for this region (see comment for that function).
239  */
tzc400_configure_region(unsigned int filters,unsigned int region,unsigned long long region_base,unsigned long long region_top,unsigned int sec_attr,unsigned int nsaid_permissions)240 void tzc400_configure_region(unsigned int filters,
241 			  unsigned int region,
242 			  unsigned long long region_base,
243 			  unsigned long long region_top,
244 			  unsigned int sec_attr,
245 			  unsigned int nsaid_permissions)
246 {
247 	assert(tzc400.base != 0U);
248 
249 	/* Adjust filter mask by real filter number */
250 	if (filters == TZC_400_REGION_ATTR_FILTER_BIT_ALL) {
251 		filters = (1U << tzc400.num_filters) - 1U;
252 	}
253 
254 	/* Do range checks on filters and regions. */
255 	assert(((filters >> tzc400.num_filters) == 0U) &&
256 	       (region < tzc400.num_regions));
257 
258 	/*
259 	 * Do address range check based on TZC configuration. A 64bit address is
260 	 * the max and expected case.
261 	 */
262 	assert((region_top <= (UINT64_MAX >> (64U - tzc400.addr_width))) &&
263 		(region_base < region_top));
264 
265 	/* region_base and (region_top + 1) must be 4KB aligned */
266 	assert(((region_base | (region_top + 1U)) & (4096U - 1U)) == 0U);
267 
268 	assert(sec_attr <= TZC_REGION_S_RDWR);
269 
270 	_tzc400_configure_region(tzc400.base, filters, region, region_base,
271 						region_top,
272 						sec_attr, nsaid_permissions);
273 }
274 
tzc400_update_filters(unsigned int region,unsigned int filters)275 void tzc400_update_filters(unsigned int region, unsigned int filters)
276 {
277 	/* Do range checks on filters and regions. */
278 	assert(((filters >> tzc400.num_filters) == 0U) &&
279 	       (region < tzc400.num_regions));
280 
281 	_tzc400_update_filters(tzc400.base, region, tzc400.num_filters, filters);
282 }
283 
tzc400_enable_filters(void)284 void tzc400_enable_filters(void)
285 {
286 	unsigned int state;
287 	unsigned int filter;
288 
289 	assert(tzc400.base != 0U);
290 
291 	for (filter = 0U; filter < tzc400.num_filters; filter++) {
292 		state = _tzc400_get_gate_keeper(tzc400.base, filter);
293 		if (state != 0U) {
294 			/* Filter 0 is special and cannot be disabled.
295 			 * So here we allow it being already enabled. */
296 			if (filter == 0U) {
297 				continue;
298 			}
299 			/*
300 			 * The TZC filter is already configured. Changing the
301 			 * programmer's view in an active system can cause
302 			 * unpredictable behavior therefore panic for now rather
303 			 * than try to determine whether this is safe in this
304 			 * instance.
305 			 *
306 			 * See the 'ARM (R) CoreLink TM TZC-400 TrustZone (R)
307 			 * Address Space Controller' Technical Reference Manual.
308 			 */
309 			ERROR("TZC-400 : Filter %d Gatekeeper already"
310 				" enabled.\n", filter);
311 			panic();
312 		}
313 		_tzc400_set_gate_keeper(tzc400.base, filter, 1);
314 	}
315 }
316 
tzc400_disable_filters(void)317 void tzc400_disable_filters(void)
318 {
319 	unsigned int filter;
320 	unsigned int state;
321 	unsigned int start = 0U;
322 
323 	assert(tzc400.base != 0U);
324 
325 	/* Filter 0 is special and cannot be disabled. */
326 	state = _tzc400_get_gate_keeper(tzc400.base, 0);
327 	if (state != 0U) {
328 		start++;
329 	}
330 	for (filter = start; filter < tzc400.num_filters; filter++)
331 		_tzc400_set_gate_keeper(tzc400.base, filter, 0);
332 }
333 
tzc400_it_handler(void)334 int tzc400_it_handler(void)
335 {
336 	uint32_t filter;
337 	uint32_t filter_it_pending = tzc400.num_filters;
338 
339 	assert(tzc400.base != 0U);
340 
341 	for (filter = 0U; filter < tzc400.num_filters; filter++) {
342 		if (_tzc400_get_int_by_filter(tzc400.base, filter) != 0U) {
343 			filter_it_pending = filter;
344 			break;
345 		}
346 	}
347 
348 	if (filter_it_pending == tzc400.num_filters) {
349 		ERROR("TZC-400: No interrupt pending!\n");
350 		return -1;
351 	}
352 
353 #if DEBUG
354 	_tzc400_dump_fail_filter(tzc400.base, filter_it_pending);
355 #endif
356 
357 	_tzc400_clear_it(tzc400.base, filter_it_pending);
358 
359 	return 0;
360 }
361