xref: /openbmc/linux/drivers/gpu/drm/tegra/firewall.c (revision f3956ebb)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2010-2020 NVIDIA Corporation */
3 
4 #include "drm.h"
5 #include "submit.h"
6 #include "uapi.h"
7 
8 struct tegra_drm_firewall {
9 	struct tegra_drm_submit_data *submit;
10 	struct tegra_drm_client *client;
11 	u32 *data;
12 	u32 pos;
13 	u32 end;
14 	u32 class;
15 };
16 
17 static int fw_next(struct tegra_drm_firewall *fw, u32 *word)
18 {
19 	if (fw->pos == fw->end)
20 		return -EINVAL;
21 
22 	*word = fw->data[fw->pos++];
23 
24 	return 0;
25 }
26 
27 static bool fw_check_addr_valid(struct tegra_drm_firewall *fw, u32 offset)
28 {
29 	u32 i;
30 
31 	for (i = 0; i < fw->submit->num_used_mappings; i++) {
32 		struct tegra_drm_mapping *m = fw->submit->used_mappings[i].mapping;
33 
34 		if (offset >= m->iova && offset <= m->iova_end)
35 			return true;
36 	}
37 
38 	return false;
39 }
40 
41 static int fw_check_reg(struct tegra_drm_firewall *fw, u32 offset)
42 {
43 	bool is_addr;
44 	u32 word;
45 	int err;
46 
47 	err = fw_next(fw, &word);
48 	if (err)
49 		return err;
50 
51 	if (!fw->client->ops->is_addr_reg)
52 		return 0;
53 
54 	is_addr = fw->client->ops->is_addr_reg(fw->client->base.dev, fw->class,
55 					       offset);
56 
57 	if (!is_addr)
58 		return 0;
59 
60 	if (!fw_check_addr_valid(fw, word))
61 		return -EINVAL;
62 
63 	return 0;
64 }
65 
66 static int fw_check_regs_seq(struct tegra_drm_firewall *fw, u32 offset,
67 			     u32 count, bool incr)
68 {
69 	u32 i;
70 
71 	for (i = 0; i < count; i++) {
72 		if (fw_check_reg(fw, offset))
73 			return -EINVAL;
74 
75 		if (incr)
76 			offset++;
77 	}
78 
79 	return 0;
80 }
81 
82 static int fw_check_regs_mask(struct tegra_drm_firewall *fw, u32 offset,
83 			      u16 mask)
84 {
85 	unsigned long bmask = mask;
86 	unsigned int bit;
87 
88 	for_each_set_bit(bit, &bmask, 16) {
89 		if (fw_check_reg(fw, offset+bit))
90 			return -EINVAL;
91 	}
92 
93 	return 0;
94 }
95 
96 static int fw_check_regs_imm(struct tegra_drm_firewall *fw, u32 offset)
97 {
98 	bool is_addr;
99 
100 	is_addr = fw->client->ops->is_addr_reg(fw->client->base.dev, fw->class,
101 					       offset);
102 	if (is_addr)
103 		return -EINVAL;
104 
105 	return 0;
106 }
107 
108 static int fw_check_class(struct tegra_drm_firewall *fw, u32 class)
109 {
110 	if (!fw->client->ops->is_valid_class) {
111 		if (class == fw->client->base.class)
112 			return 0;
113 		else
114 			return -EINVAL;
115 	}
116 
117 	if (!fw->client->ops->is_valid_class(class))
118 		return -EINVAL;
119 
120 	return 0;
121 }
122 
123 enum {
124 	HOST1X_OPCODE_SETCLASS  = 0x00,
125 	HOST1X_OPCODE_INCR      = 0x01,
126 	HOST1X_OPCODE_NONINCR   = 0x02,
127 	HOST1X_OPCODE_MASK      = 0x03,
128 	HOST1X_OPCODE_IMM       = 0x04,
129 	HOST1X_OPCODE_RESTART   = 0x05,
130 	HOST1X_OPCODE_GATHER    = 0x06,
131 	HOST1X_OPCODE_SETSTRMID = 0x07,
132 	HOST1X_OPCODE_SETAPPID  = 0x08,
133 	HOST1X_OPCODE_SETPYLD   = 0x09,
134 	HOST1X_OPCODE_INCR_W    = 0x0a,
135 	HOST1X_OPCODE_NONINCR_W = 0x0b,
136 	HOST1X_OPCODE_GATHER_W  = 0x0c,
137 	HOST1X_OPCODE_RESTART_W = 0x0d,
138 	HOST1X_OPCODE_EXTEND    = 0x0e,
139 };
140 
141 int tegra_drm_fw_validate(struct tegra_drm_client *client, u32 *data, u32 start,
142 			  u32 words, struct tegra_drm_submit_data *submit,
143 			  u32 *job_class)
144 {
145 	struct tegra_drm_firewall fw = {
146 		.submit = submit,
147 		.client = client,
148 		.data = data,
149 		.pos = start,
150 		.end = start+words,
151 		.class = *job_class,
152 	};
153 	bool payload_valid = false;
154 	u32 payload;
155 	int err;
156 
157 	while (fw.pos != fw.end) {
158 		u32 word, opcode, offset, count, mask, class;
159 
160 		err = fw_next(&fw, &word);
161 		if (err)
162 			return err;
163 
164 		opcode = (word & 0xf0000000) >> 28;
165 
166 		switch (opcode) {
167 		case HOST1X_OPCODE_SETCLASS:
168 			offset = word >> 16 & 0xfff;
169 			mask = word & 0x3f;
170 			class = (word >> 6) & 0x3ff;
171 			err = fw_check_class(&fw, class);
172 			fw.class = class;
173 			*job_class = class;
174 			if (!err)
175 				err = fw_check_regs_mask(&fw, offset, mask);
176 			if (err)
177 				dev_warn(client->base.dev,
178 					 "illegal SETCLASS(offset=0x%x, mask=0x%x, class=0x%x) at word %u",
179 					 offset, mask, class, fw.pos-1);
180 			break;
181 		case HOST1X_OPCODE_INCR:
182 			offset = (word >> 16) & 0xfff;
183 			count = word & 0xffff;
184 			err = fw_check_regs_seq(&fw, offset, count, true);
185 			if (err)
186 				dev_warn(client->base.dev,
187 					 "illegal INCR(offset=0x%x, count=%u) in class 0x%x at word %u",
188 					 offset, count, fw.class, fw.pos-1);
189 			break;
190 		case HOST1X_OPCODE_NONINCR:
191 			offset = (word >> 16) & 0xfff;
192 			count = word & 0xffff;
193 			err = fw_check_regs_seq(&fw, offset, count, false);
194 			if (err)
195 				dev_warn(client->base.dev,
196 					 "illegal NONINCR(offset=0x%x, count=%u) in class 0x%x at word %u",
197 					 offset, count, fw.class, fw.pos-1);
198 			break;
199 		case HOST1X_OPCODE_MASK:
200 			offset = (word >> 16) & 0xfff;
201 			mask = word & 0xffff;
202 			err = fw_check_regs_mask(&fw, offset, mask);
203 			if (err)
204 				dev_warn(client->base.dev,
205 					 "illegal MASK(offset=0x%x, mask=0x%x) in class 0x%x at word %u",
206 					 offset, mask, fw.class, fw.pos-1);
207 			break;
208 		case HOST1X_OPCODE_IMM:
209 			/* IMM cannot reasonably be used to write a pointer */
210 			offset = (word >> 16) & 0xfff;
211 			err = fw_check_regs_imm(&fw, offset);
212 			if (err)
213 				dev_warn(client->base.dev,
214 					 "illegal IMM(offset=0x%x) in class 0x%x at word %u",
215 					 offset, fw.class, fw.pos-1);
216 			break;
217 		case HOST1X_OPCODE_SETPYLD:
218 			payload = word & 0xffff;
219 			payload_valid = true;
220 			break;
221 		case HOST1X_OPCODE_INCR_W:
222 			if (!payload_valid)
223 				return -EINVAL;
224 
225 			offset = word & 0x3fffff;
226 			err = fw_check_regs_seq(&fw, offset, payload, true);
227 			if (err)
228 				dev_warn(client->base.dev,
229 					 "illegal INCR_W(offset=0x%x) in class 0x%x at word %u",
230 					 offset, fw.class, fw.pos-1);
231 			break;
232 		case HOST1X_OPCODE_NONINCR_W:
233 			if (!payload_valid)
234 				return -EINVAL;
235 
236 			offset = word & 0x3fffff;
237 			err = fw_check_regs_seq(&fw, offset, payload, false);
238 			if (err)
239 				dev_warn(client->base.dev,
240 					 "illegal NONINCR(offset=0x%x) in class 0x%x at word %u",
241 					 offset, fw.class, fw.pos-1);
242 			break;
243 		default:
244 			dev_warn(client->base.dev, "illegal opcode at word %u",
245 				 fw.pos-1);
246 			return -EINVAL;
247 		}
248 
249 		if (err)
250 			return err;
251 	}
252 
253 	return 0;
254 }
255