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_CONFIGURE_REGION0(400)
72 DEFINE_TZC_COMMON_CONFIGURE_REGION(400)
73 
_tzc400_clear_it(uintptr_t base,uint32_t filter)74 static void _tzc400_clear_it(uintptr_t base, uint32_t filter)
75 {
76 	mmio_write_32(base + INT_CLEAR, BIT_32(filter));
77 }
78 
_tzc400_get_int_by_filter(uintptr_t base,uint32_t filter)79 static uint32_t _tzc400_get_int_by_filter(uintptr_t base, uint32_t filter)
80 {
81 	return mmio_read_32(base + INT_STATUS) & BIT_32(filter);
82 }
83 
84 #if DEBUG
_tzc400_get_fail_address(uintptr_t base,uint32_t filter)85 static unsigned long _tzc400_get_fail_address(uintptr_t base, uint32_t filter)
86 {
87 	unsigned long fail_address;
88 
89 	fail_address = mmio_read_32(base + FAIL_ADDRESS_LOW_OFF +
90 				    (filter * FILTER_OFFSET));
91 #ifdef __aarch64__
92 	fail_address += (unsigned long)mmio_read_32(base + FAIL_ADDRESS_HIGH_OFF +
93 						    (filter * FILTER_OFFSET)) << 32;
94 #endif
95 
96 	return fail_address;
97 }
98 
_tzc400_get_fail_id(uintptr_t base,uint32_t filter)99 static uint32_t _tzc400_get_fail_id(uintptr_t base, uint32_t filter)
100 {
101 	return mmio_read_32(base + FAIL_ID + (filter * FILTER_OFFSET));
102 }
103 
_tzc400_get_fail_control(uintptr_t base,uint32_t filter)104 static uint32_t _tzc400_get_fail_control(uintptr_t base, uint32_t filter)
105 {
106 	return mmio_read_32(base + FAIL_CONTROL_OFF + (filter * FILTER_OFFSET));
107 }
108 
_tzc400_dump_fail_filter(uintptr_t base,uint32_t filter)109 static void _tzc400_dump_fail_filter(uintptr_t base, uint32_t filter)
110 {
111 	uint32_t control_fail;
112 	uint32_t fail_id;
113 	unsigned long address_fail;
114 
115 	address_fail = _tzc400_get_fail_address(base, filter);
116 	ERROR("Illegal access to 0x%lx:\n", address_fail);
117 
118 	fail_id = _tzc400_get_fail_id(base, filter);
119 	ERROR("\tFAIL_ID = 0x%x\n", fail_id);
120 
121 	control_fail = _tzc400_get_fail_control(base, filter);
122 	if (((control_fail & BIT_32(FAIL_CONTROL_NS_SHIFT)) >> FAIL_CONTROL_NS_SHIFT) ==
123 	    FAIL_CONTROL_NS_NONSECURE) {
124 		ERROR("\tNon-Secure\n");
125 	} else {
126 		ERROR("\tSecure\n");
127 	}
128 
129 	if (((control_fail & BIT_32(FAIL_CONTROL_PRIV_SHIFT)) >> FAIL_CONTROL_PRIV_SHIFT) ==
130 	    FAIL_CONTROL_PRIV_PRIV) {
131 		ERROR("\tPrivilege\n");
132 	} else {
133 		ERROR("\tUnprivilege\n");
134 	}
135 
136 	if (((control_fail & BIT_32(FAIL_CONTROL_DIR_SHIFT)) >> FAIL_CONTROL_DIR_SHIFT) ==
137 	    FAIL_CONTROL_DIR_WRITE) {
138 		ERROR("\tWrite\n");
139 	} else {
140 		ERROR("\tRead\n");
141 	}
142 }
143 #endif /* DEBUG */
144 
_tzc400_get_gate_keeper(uintptr_t base,unsigned int filter)145 static unsigned int _tzc400_get_gate_keeper(uintptr_t base,
146 				unsigned int filter)
147 {
148 	unsigned int open_status;
149 
150 	open_status = get_gate_keeper_os(base);
151 
152 	return (open_status >> filter) & GATE_KEEPER_FILTER_MASK;
153 }
154 
155 /* This function is not MP safe. */
_tzc400_set_gate_keeper(uintptr_t base,unsigned int filter,int val)156 static void _tzc400_set_gate_keeper(uintptr_t base,
157 				unsigned int filter,
158 				int val)
159 {
160 	unsigned int open_status;
161 
162 	/* Upper half is current state. Lower half is requested state. */
163 	open_status = get_gate_keeper_os(base);
164 
165 	if (val != 0)
166 		open_status |=  (1UL << filter);
167 	else
168 		open_status &= ~(1UL << filter);
169 
170 	_tzc400_write_gate_keeper(base, (open_status & GATE_KEEPER_OR_MASK) <<
171 			      GATE_KEEPER_OR_SHIFT);
172 
173 	/* Wait here until we see the change reflected in the TZC status. */
174 	while ((get_gate_keeper_os(base)) != open_status)
175 		;
176 }
177 
tzc400_set_action(unsigned int action)178 void tzc400_set_action(unsigned int action)
179 {
180 	assert(tzc400.base != 0U);
181 	assert(action <= TZC_ACTION_ERR_INT);
182 
183 	_tzc400_write_action(tzc400.base, action);
184 }
185 
tzc400_init(uintptr_t base)186 void tzc400_init(uintptr_t base)
187 {
188 #if DEBUG
189 	unsigned int tzc400_id;
190 #endif
191 	unsigned int tzc400_build;
192 
193 	assert(base != 0U);
194 	tzc400.base = base;
195 
196 #if DEBUG
197 	tzc400_id = _tzc_read_peripheral_id(base);
198 	if (tzc400_id != TZC_400_PERIPHERAL_ID) {
199 		ERROR("TZC-400 : Wrong device ID (0x%x).\n", tzc400_id);
200 		panic();
201 	}
202 #endif
203 
204 	/* Save values we will use later. */
205 	tzc400_build = _tzc400_read_build_config(tzc400.base);
206 	tzc400.num_filters = (uint8_t)((tzc400_build >> BUILD_CONFIG_NF_SHIFT) &
207 					BUILD_CONFIG_NF_MASK) + 1U;
208 	tzc400.addr_width  = (uint8_t)((tzc400_build >> BUILD_CONFIG_AW_SHIFT) &
209 					BUILD_CONFIG_AW_MASK) + 1U;
210 	tzc400.num_regions = (uint8_t)((tzc400_build >> BUILD_CONFIG_NR_SHIFT) &
211 					BUILD_CONFIG_NR_MASK) + 1U;
212 }
213 
214 /*
215  * `tzc400_configure_region0` is used to program region 0 into the TrustZone
216  * controller. Region 0 covers the whole address space that is not mapped
217  * to any other region, and is enabled on all filters; this cannot be
218  * changed. This function only changes the access permissions.
219  */
tzc400_configure_region0(unsigned int sec_attr,unsigned int ns_device_access)220 void tzc400_configure_region0(unsigned int sec_attr,
221 			   unsigned int ns_device_access)
222 {
223 	assert(tzc400.base != 0U);
224 	assert(sec_attr <= TZC_REGION_S_RDWR);
225 
226 	_tzc400_configure_region0(tzc400.base, sec_attr, ns_device_access);
227 }
228 
229 /*
230  * `tzc400_configure_region` is used to program regions into the TrustZone
231  * controller. A region can be associated with more than one filter. The
232  * associated filters are passed in as a bitmap (bit0 = filter0), except that
233  * the value TZC_400_REGION_ATTR_FILTER_BIT_ALL selects all filters, based on
234  * the value of tzc400.num_filters.
235  * NOTE:
236  * Region 0 is special; it is preferable to use tzc400_configure_region0
237  * for this region (see comment for that function).
238  */
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)239 void tzc400_configure_region(unsigned int filters,
240 			  unsigned int region,
241 			  unsigned long long region_base,
242 			  unsigned long long region_top,
243 			  unsigned int sec_attr,
244 			  unsigned int nsaid_permissions)
245 {
246 	assert(tzc400.base != 0U);
247 
248 	/* Adjust filter mask by real filter number */
249 	if (filters == TZC_400_REGION_ATTR_FILTER_BIT_ALL) {
250 		filters = (1U << tzc400.num_filters) - 1U;
251 	}
252 
253 	/* Do range checks on filters and regions. */
254 	assert(((filters >> tzc400.num_filters) == 0U) &&
255 	       (region < tzc400.num_regions));
256 
257 	/*
258 	 * Do address range check based on TZC configuration. A 64bit address is
259 	 * the max and expected case.
260 	 */
261 	assert((region_top <= (UINT64_MAX >> (64U - tzc400.addr_width))) &&
262 		(region_base < region_top));
263 
264 	/* region_base and (region_top + 1) must be 4KB aligned */
265 	assert(((region_base | (region_top + 1U)) & (4096U - 1U)) == 0U);
266 
267 	assert(sec_attr <= TZC_REGION_S_RDWR);
268 
269 	_tzc400_configure_region(tzc400.base, filters, region, region_base,
270 						region_top,
271 						sec_attr, nsaid_permissions);
272 }
273 
tzc400_enable_filters(void)274 void tzc400_enable_filters(void)
275 {
276 	unsigned int state;
277 	unsigned int filter;
278 
279 	assert(tzc400.base != 0U);
280 
281 	for (filter = 0U; filter < tzc400.num_filters; filter++) {
282 		state = _tzc400_get_gate_keeper(tzc400.base, filter);
283 		if (state != 0U) {
284 			/*
285 			 * The TZC filter is already configured. Changing the
286 			 * programmer's view in an active system can cause
287 			 * unpredictable behavior therefore panic for now rather
288 			 * than try to determine whether this is safe in this
289 			 * instance.
290 			 *
291 			 * See the 'ARM (R) CoreLink TM TZC-400 TrustZone (R)
292 			 * Address Space Controller' Technical Reference Manual.
293 			 */
294 			ERROR("TZC-400 : Filter %d Gatekeeper already"
295 				" enabled.\n", filter);
296 			panic();
297 		}
298 		_tzc400_set_gate_keeper(tzc400.base, filter, 1);
299 	}
300 }
301 
tzc400_disable_filters(void)302 void tzc400_disable_filters(void)
303 {
304 	unsigned int filter;
305 
306 	assert(tzc400.base != 0U);
307 
308 	/*
309 	 * We don't do the same state check as above as the Gatekeepers are
310 	 * disabled after reset.
311 	 */
312 	for (filter = 0; filter < tzc400.num_filters; filter++)
313 		_tzc400_set_gate_keeper(tzc400.base, filter, 0);
314 }
315 
tzc400_it_handler(void)316 int tzc400_it_handler(void)
317 {
318 	uint32_t filter;
319 	uint32_t filter_it_pending = tzc400.num_filters;
320 
321 	assert(tzc400.base != 0U);
322 
323 	for (filter = 0U; filter < tzc400.num_filters; filter++) {
324 		if (_tzc400_get_int_by_filter(tzc400.base, filter) != 0U) {
325 			filter_it_pending = filter;
326 			break;
327 		}
328 	}
329 
330 	if (filter_it_pending == tzc400.num_filters) {
331 		ERROR("TZC-400: No interrupt pending!\n");
332 		return -1;
333 	}
334 
335 #if DEBUG
336 	_tzc400_dump_fail_filter(tzc400.base, filter_it_pending);
337 #endif
338 
339 	_tzc400_clear_it(tzc400.base, filter_it_pending);
340 
341 	return 0;
342 }
343