summaryrefslogtreecommitdiff
path: root/drivers/arm/tzc/tzc400.c
blob: 8c6f8ba6b694873ce872705a807ff515662f0c80 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
/*
 * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of ARM nor the names of its contributors may be used
 * to endorse or promote products derived from this software without specific
 * prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <assert.h>
#include <debug.h>
#include <mmio.h>
#include <stddef.h>
#include <tzc400.h>
#include "tzc_common_private.h"

/*
 * Macros which will be used by common core functions.
 */
#define TZC_400_REGION_BASE_LOW_0_OFFSET	0x100
#define TZC_400_REGION_BASE_HIGH_0_OFFSET	0x104
#define TZC_400_REGION_TOP_LOW_0_OFFSET		0x108
#define TZC_400_REGION_TOP_HIGH_0_OFFSET	0x10c
#define TZC_400_REGION_ATTR_0_OFFSET		0x110
#define TZC_400_REGION_ID_ACCESS_0_OFFSET	0x114

/*
 * Implementation defined values used to validate inputs later.
 * Filters : max of 4 ; 0 to 3
 * Regions : max of 9 ; 0 to 8
 * Address width : Values between 32 to 64
 */
typedef struct tzc400_instance {
	uintptr_t base;
	uint8_t addr_width;
	uint8_t num_filters;
	uint8_t num_regions;
} tzc400_instance_t;

tzc400_instance_t tzc400;

static inline unsigned int _tzc400_read_build_config(uintptr_t base)
{
	return mmio_read_32(base + BUILD_CONFIG_OFF);
}

static inline unsigned int _tzc400_read_gate_keeper(uintptr_t base)
{
	return mmio_read_32(base + GATE_KEEPER_OFF);
}

static inline void _tzc400_write_gate_keeper(uintptr_t base, unsigned int val)
{
	mmio_write_32(base + GATE_KEEPER_OFF, val);
}

/*
 * Get the open status information for all filter units.
 */
#define get_gate_keeper_os(base)	((_tzc400_read_gate_keeper(base) >>	\
					GATE_KEEPER_OS_SHIFT) &		\
					GATE_KEEPER_OS_MASK)


/* Define common core functions used across different TZC peripherals. */
DEFINE_TZC_COMMON_WRITE_ACTION(400, 400)
DEFINE_TZC_COMMON_WRITE_REGION_BASE(400, 400)
DEFINE_TZC_COMMON_WRITE_REGION_TOP(400, 400)
DEFINE_TZC_COMMON_WRITE_REGION_ATTRIBUTES(400, 400)
DEFINE_TZC_COMMON_WRITE_REGION_ID_ACCESS(400, 400)
DEFINE_TZC_COMMON_CONFIGURE_REGION0(400)
DEFINE_TZC_COMMON_CONFIGURE_REGION(400)

static unsigned int _tzc400_get_gate_keeper(uintptr_t base,
				unsigned int filter)
{
	unsigned int open_status;

	open_status = get_gate_keeper_os(base);

	return (open_status >> filter) & GATE_KEEPER_FILTER_MASK;
}

/* This function is not MP safe. */
static void _tzc400_set_gate_keeper(uintptr_t base,
				unsigned int filter,
				int val)
{
	unsigned int open_status;

	/* Upper half is current state. Lower half is requested state. */
	open_status = get_gate_keeper_os(base);

	if (val)
		open_status |=  (1 << filter);
	else
		open_status &= ~(1 << filter);

	_tzc400_write_gate_keeper(base, (open_status & GATE_KEEPER_OR_MASK) <<
			      GATE_KEEPER_OR_SHIFT);

	/* Wait here until we see the change reflected in the TZC status. */
	while ((get_gate_keeper_os(base)) != open_status)
		;
}

void tzc400_set_action(tzc_action_t action)
{
	assert(tzc400.base);
	assert(action <= TZC_ACTION_ERR_INT);

	/*
	 * - Currently no handler is provided to trap an error via interrupt
	 *   or exception.
	 * - The interrupt action has not been tested.
	 */
	_tzc400_write_action(tzc400.base, action);
}

void tzc400_init(uintptr_t base)
{
#if DEBUG
	unsigned int tzc400_id;
#endif
	unsigned int tzc400_build;

	assert(base);
	tzc400.base = base;

#if DEBUG
	tzc400_id = _tzc_read_peripheral_id(base);
	if (tzc400_id != TZC_400_PERIPHERAL_ID) {
		ERROR("TZC-400 : Wrong device ID (0x%x).\n", tzc400_id);
		panic();
	}
#endif

	/* Save values we will use later. */
	tzc400_build = _tzc400_read_build_config(tzc400.base);
	tzc400.num_filters = ((tzc400_build >> BUILD_CONFIG_NF_SHIFT) &
			   BUILD_CONFIG_NF_MASK) + 1;
	tzc400.addr_width  = ((tzc400_build >> BUILD_CONFIG_AW_SHIFT) &
			   BUILD_CONFIG_AW_MASK) + 1;
	tzc400.num_regions = ((tzc400_build >> BUILD_CONFIG_NR_SHIFT) &
			   BUILD_CONFIG_NR_MASK) + 1;
}

/*
 * `tzc400_configure_region0` is used to program region 0 into the TrustZone
 * controller. Region 0 covers the whole address space that is not mapped
 * to any other region, and is enabled on all filters; this cannot be
 * changed. This function only changes the access permissions.
 */
void tzc400_configure_region0(tzc_region_attributes_t sec_attr,
			   unsigned int ns_device_access)
{
	assert(tzc400.base);
	assert(sec_attr <= TZC_REGION_S_RDWR);

	_tzc400_configure_region0(tzc400.base, sec_attr, ns_device_access);
}

/*
 * `tzc400_configure_region` is used to program regions into the TrustZone
 * controller. A region can be associated with more than one filter. The
 * associated filters are passed in as a bitmap (bit0 = filter0).
 * NOTE:
 * Region 0 is special; it is preferable to use tzc400_configure_region0
 * for this region (see comment for that function).
 */
void tzc400_configure_region(unsigned int filters,
			  int region,
			  unsigned long long region_base,
			  unsigned long long region_top,
			  tzc_region_attributes_t sec_attr,
			  unsigned int nsaid_permissions)
{
	assert(tzc400.base);

	/* Do range checks on filters and regions. */
	assert(((filters >> tzc400.num_filters) == 0) &&
	       (region >= 0) && (region < tzc400.num_regions));

	/*
	 * Do address range check based on TZC configuration. A 64bit address is
	 * the max and expected case.
	 */
	assert(((region_top <= _tzc_get_max_top_addr(tzc400.addr_width)) &&
		(region_base < region_top)));

	/* region_base and (region_top + 1) must be 4KB aligned */
	assert(((region_base | (region_top + 1)) & (4096 - 1)) == 0);

	assert(sec_attr <= TZC_REGION_S_RDWR);

	_tzc400_configure_region(tzc400.base, filters, region, region_base,
						region_top,
						sec_attr, nsaid_permissions);
}

void tzc400_enable_filters(void)
{
	unsigned int state;
	unsigned int filter;

	assert(tzc400.base);

	for (filter = 0; filter < tzc400.num_filters; filter++) {
		state = _tzc400_get_gate_keeper(tzc400.base, filter);
		if (state) {
			/* The TZC filter is already configured. Changing the
			 * programmer's view in an active system can cause
			 * unpredictable behavior therefore panic for now rather
			 * than try to determine whether this is safe in this
			 * instance. See:
			 * http://infocenter.arm.com/help/index.jsp?\
			 * topic=/com.arm.doc.ddi0504c/CJHHECBF.html */
			ERROR("TZC-400 : Filter %d Gatekeeper already"
				" enabled.\n", filter);
			panic();
		}
		_tzc400_set_gate_keeper(tzc400.base, filter, 1);
	}
}

void tzc400_disable_filters(void)
{
	unsigned int filter;

	assert(tzc400.base);

	/*
	 * We don't do the same state check as above as the Gatekeepers are
	 * disabled after reset.
	 */
	for (filter = 0; filter < tzc400.num_filters; filter++)
		_tzc400_set_gate_keeper(tzc400.base, filter, 0);
}