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1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2016 NXP Semiconductor, Inc.
4  */
5 
6 #include <common.h>
7 #include <cpu_func.h>
8 #include <errno.h>
9 #include <linux/kernel.h>
10 #include <asm/io.h>
11 #include <asm/system.h>
12 #include <asm/types.h>
13 #include <asm/macro.h>
14 #include <asm/armv8/sec_firmware.h>
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 extern void c_runtime_cpu_setup(void);
18 
19 #define SEC_FIRMWARE_LOADED	0x1
20 #define SEC_FIRMWARE_RUNNING	0x2
21 #define SEC_FIRMWARE_ADDR_MASK	(~0x3)
22 /*
23  * Secure firmware load addr
24  * Flags used: 0x1 secure firmware has been loaded to secure memory
25  *             0x2 secure firmware is running
26  */
27 phys_addr_t sec_firmware_addr;
28 
29 #ifndef SEC_FIRMWARE_FIT_IMAGE
30 #define SEC_FIRMWARE_FIT_IMAGE		"firmware"
31 #endif
32 #ifndef SEC_FIRMWARE_FIT_CNF_NAME
33 #define SEC_FIRMWARE_FIT_CNF_NAME	"config-1"
34 #endif
35 #ifndef SEC_FIRMWARE_TARGET_EL
36 #define SEC_FIRMWARE_TARGET_EL		2
37 #endif
38 
sec_firmware_get_data(const void * sec_firmware_img,const void ** data,size_t * size)39 static int sec_firmware_get_data(const void *sec_firmware_img,
40 				const void **data, size_t *size)
41 {
42 	int conf_node_off, fw_node_off;
43 	char *conf_node_name = NULL;
44 	char *desc;
45 	int ret;
46 
47 	conf_node_name = SEC_FIRMWARE_FIT_CNF_NAME;
48 
49 	conf_node_off = fit_conf_get_node(sec_firmware_img, conf_node_name);
50 	if (conf_node_off < 0) {
51 		printf("SEC Firmware: %s: no such config\n", conf_node_name);
52 		return -ENOENT;
53 	}
54 
55 	fw_node_off = fit_conf_get_prop_node(sec_firmware_img, conf_node_off,
56 			SEC_FIRMWARE_FIT_IMAGE);
57 	if (fw_node_off < 0) {
58 		printf("SEC Firmware: No '%s' in config\n",
59 		       SEC_FIRMWARE_FIT_IMAGE);
60 		return -ENOLINK;
61 	}
62 
63 	/* Verify secure firmware image */
64 	if (!(fit_image_verify(sec_firmware_img, fw_node_off))) {
65 		printf("SEC Firmware: Bad firmware image (bad CRC)\n");
66 		return -EINVAL;
67 	}
68 
69 	if (fit_image_get_data(sec_firmware_img, fw_node_off, data, size)) {
70 		printf("SEC Firmware: Can't get %s subimage data/size",
71 		       SEC_FIRMWARE_FIT_IMAGE);
72 		return -ENOENT;
73 	}
74 
75 	ret = fit_get_desc(sec_firmware_img, fw_node_off, &desc);
76 	if (ret)
77 		printf("SEC Firmware: Can't get description\n");
78 	else
79 		printf("%s\n", desc);
80 
81 	return ret;
82 }
83 
84 /*
85  * SEC Firmware FIT image parser checks if the image is in FIT
86  * format, verifies integrity of the image and calculates raw
87  * image address and size values.
88  *
89  * Returns 0 on success and a negative errno on error task fail.
90  */
sec_firmware_parse_image(const void * sec_firmware_img,const void ** raw_image_addr,size_t * raw_image_size)91 static int sec_firmware_parse_image(const void *sec_firmware_img,
92 					const void **raw_image_addr,
93 					size_t *raw_image_size)
94 {
95 	int ret;
96 
97 	ret = sec_firmware_get_data(sec_firmware_img, raw_image_addr,
98 					raw_image_size);
99 	if (ret)
100 		return ret;
101 
102 	debug("SEC Firmware: raw_image_addr = 0x%p, raw_image_size = 0x%lx\n",
103 	      *raw_image_addr, *raw_image_size);
104 
105 	return 0;
106 }
107 
108 /*
109  * SEC Firmware FIT image parser to check if any loadable is
110  * present. If present, verify integrity of the loadable and
111  * copy loadable to address provided in (loadable_h, loadable_l).
112  *
113  * Returns 0 on success and a negative errno on error task fail.
114  */
sec_firmware_check_copy_loadable(const void * sec_firmware_img,u32 * loadable_l,u32 * loadable_h)115 static int sec_firmware_check_copy_loadable(const void *sec_firmware_img,
116 					    u32 *loadable_l, u32 *loadable_h)
117 {
118 	phys_addr_t sec_firmware_loadable_addr = 0;
119 	int conf_node_off, ld_node_off, images;
120 	char *conf_node_name = NULL;
121 	const void *data;
122 	size_t size;
123 	ulong load;
124 	const char *name, *str, *type;
125 	int len;
126 
127 	conf_node_name = SEC_FIRMWARE_FIT_CNF_NAME;
128 
129 	conf_node_off = fit_conf_get_node(sec_firmware_img, conf_node_name);
130 	if (conf_node_off < 0) {
131 		printf("SEC Firmware: %s: no such config\n", conf_node_name);
132 		return -ENOENT;
133 	}
134 
135 	/* find the node holding the images information */
136 	images = fdt_path_offset(sec_firmware_img, FIT_IMAGES_PATH);
137 	if (images < 0) {
138 		printf("%s: Cannot find /images node: %d\n", __func__, images);
139 		return -1;
140 	}
141 
142 	type = FIT_LOADABLE_PROP;
143 
144 	name = fdt_getprop(sec_firmware_img, conf_node_off, type, &len);
145 	if (!name) {
146 		/* Loadables not present */
147 		return 0;
148 	}
149 
150 	printf("SEC Firmware: '%s' present in config\n", type);
151 
152 	for (str = name; str && ((str - name) < len);
153 	     str = strchr(str, '\0') + 1) {
154 		printf("%s: '%s'\n", type, str);
155 		ld_node_off = fdt_subnode_offset(sec_firmware_img, images, str);
156 		if (ld_node_off < 0) {
157 			printf("cannot find image node '%s': %d\n", str,
158 			       ld_node_off);
159 			return -EINVAL;
160 		}
161 
162 		/* Verify secure firmware image */
163 		if (!(fit_image_verify(sec_firmware_img, ld_node_off))) {
164 			printf("SEC Loadable: Bad loadable image (bad CRC)\n");
165 			return -EINVAL;
166 		}
167 
168 		if (fit_image_get_data(sec_firmware_img, ld_node_off,
169 				       &data, &size)) {
170 			printf("SEC Loadable: Can't get subimage data/size");
171 			return -ENOENT;
172 		}
173 
174 		/* Get load address, treated as load offset to secure memory */
175 		if (fit_image_get_load(sec_firmware_img, ld_node_off, &load)) {
176 			printf("SEC Loadable: Can't get subimage load");
177 			return -ENOENT;
178 		}
179 
180 		/* Compute load address for loadable in secure memory */
181 		sec_firmware_loadable_addr = (sec_firmware_addr -
182 						gd->arch.tlb_size) + load;
183 
184 		/* Copy loadable to secure memory and flush dcache */
185 		debug("%s copied to address 0x%p\n",
186 		      FIT_LOADABLE_PROP, (void *)sec_firmware_loadable_addr);
187 		memcpy((void *)sec_firmware_loadable_addr, data, size);
188 		flush_dcache_range(sec_firmware_loadable_addr,
189 				   sec_firmware_loadable_addr + size);
190 
191 		/* Populate loadable address only for Trusted OS */
192 		if (!strcmp(str, "trustedOS@1")) {
193 			/*
194 			 * Populate address ptrs for loadable image with
195 			 * loadbale addr
196 			 */
197 			out_le32(loadable_l, (sec_firmware_loadable_addr &
198 					      WORD_MASK));
199 			out_le32(loadable_h, (sec_firmware_loadable_addr >>
200 					      WORD_SHIFT));
201 		}
202 	}
203 
204 	return 0;
205 }
206 
sec_firmware_copy_image(const char * title,u64 image_addr,u32 image_size,u64 sec_firmware)207 static int sec_firmware_copy_image(const char *title,
208 			 u64 image_addr, u32 image_size, u64 sec_firmware)
209 {
210 	debug("%s copied to address 0x%p\n", title, (void *)sec_firmware);
211 	memcpy((void *)sec_firmware, (void *)image_addr, image_size);
212 	flush_dcache_range(sec_firmware, sec_firmware + image_size);
213 
214 	return 0;
215 }
216 
217 /*
218  * This function will parse the SEC Firmware image, and then load it
219  * to secure memory. Also load any loadable if present along with SEC
220  * Firmware image.
221  */
sec_firmware_load_image(const void * sec_firmware_img,u32 * loadable_l,u32 * loadable_h)222 static int sec_firmware_load_image(const void *sec_firmware_img,
223 				   u32 *loadable_l, u32 *loadable_h)
224 {
225 	const void *raw_image_addr;
226 	size_t raw_image_size = 0;
227 	int ret;
228 
229 	/*
230 	 * The Excetpion Level must be EL3 to load and initialize
231 	 * the SEC Firmware.
232 	 */
233 	if (current_el() != 3) {
234 		ret = -EACCES;
235 		goto out;
236 	}
237 
238 #ifdef CONFIG_SYS_MEM_RESERVE_SECURE
239 	/*
240 	 * The SEC Firmware must be stored in secure memory.
241 	 * Append SEC Firmware to secure mmu table.
242 	 */
243 	if (!(gd->arch.secure_ram & MEM_RESERVE_SECURE_MAINTAINED)) {
244 		ret = -ENXIO;
245 		goto out;
246 	}
247 
248 	sec_firmware_addr = (gd->arch.secure_ram & MEM_RESERVE_SECURE_ADDR_MASK) +
249 			gd->arch.tlb_size;
250 #else
251 #error "The CONFIG_SYS_MEM_RESERVE_SECURE must be defined when enabled SEC Firmware support"
252 #endif
253 
254 	/* Align SEC Firmware base address to 4K */
255 	sec_firmware_addr = (sec_firmware_addr + 0xfff) & ~0xfff;
256 	debug("SEC Firmware: Load address: 0x%llx\n",
257 	      sec_firmware_addr & SEC_FIRMWARE_ADDR_MASK);
258 
259 	ret = sec_firmware_parse_image(sec_firmware_img, &raw_image_addr,
260 			&raw_image_size);
261 	if (ret)
262 		goto out;
263 
264 	/* TODO:
265 	 * Check if the end addr of SEC Firmware has been extend the secure
266 	 * memory.
267 	 */
268 
269 	/* Copy the secure firmware to secure memory */
270 	ret = sec_firmware_copy_image("SEC Firmware", (u64)raw_image_addr,
271 			raw_image_size, sec_firmware_addr &
272 			SEC_FIRMWARE_ADDR_MASK);
273 	if (ret)
274 		goto out;
275 
276 	/*
277 	 * Check if any loadable are present along with firmware image, if
278 	 * present load them.
279 	 */
280 	ret = sec_firmware_check_copy_loadable(sec_firmware_img, loadable_l,
281 					       loadable_h);
282 	if (ret)
283 		goto out;
284 
285 	sec_firmware_addr |= SEC_FIRMWARE_LOADED;
286 	debug("SEC Firmware: Entry point: 0x%llx\n",
287 	      sec_firmware_addr & SEC_FIRMWARE_ADDR_MASK);
288 
289 	return 0;
290 
291 out:
292 	printf("SEC Firmware: error (%d)\n", ret);
293 	sec_firmware_addr = 0;
294 
295 	return ret;
296 }
297 
sec_firmware_entry(u32 * eret_hold_l,u32 * eret_hold_h)298 static int sec_firmware_entry(u32 *eret_hold_l, u32 *eret_hold_h)
299 {
300 	const void *entry = (void *)(sec_firmware_addr &
301 				SEC_FIRMWARE_ADDR_MASK);
302 
303 	return _sec_firmware_entry(entry, eret_hold_l, eret_hold_h);
304 }
305 
306 /* Check the secure firmware FIT image */
sec_firmware_is_valid(const void * sec_firmware_img)307 __weak bool sec_firmware_is_valid(const void *sec_firmware_img)
308 {
309 	if (fdt_check_header(sec_firmware_img)) {
310 		printf("SEC Firmware: Bad firmware image (not a FIT image)\n");
311 		return false;
312 	}
313 
314 	if (!fit_check_format(sec_firmware_img)) {
315 		printf("SEC Firmware: Bad firmware image (bad FIT header)\n");
316 		return false;
317 	}
318 
319 	return true;
320 }
321 
322 #ifdef CONFIG_SEC_FIRMWARE_ARMV8_PSCI
323 /*
324  * The PSCI_VERSION function is added from PSCI v0.2. When the PSCI
325  * v0.1 received this function, the NOT_SUPPORTED (0xffff_ffff) error
326  * number will be returned according to SMC Calling Conventions. But
327  * when getting the NOT_SUPPORTED error number, we cannot ensure if
328  * the PSCI version is v0.1 or other error occurred. So, PSCI v0.1
329  * won't be supported by this framework.
330  * And if the secure firmware isn't running, return NOT_SUPPORTED.
331  *
332  * The return value on success is PSCI version in format
333  * major[31:16]:minor[15:0].
334  */
sec_firmware_support_psci_version(void)335 unsigned int sec_firmware_support_psci_version(void)
336 {
337 	if (current_el() == SEC_FIRMWARE_TARGET_EL)
338 		return _sec_firmware_support_psci_version();
339 
340 	return PSCI_INVALID_VER;
341 }
342 #endif
343 
344 /*
345  * Check with sec_firmware if it supports random number generation
346  * via HW RNG
347  *
348  * The return value will be true if it is supported
349  */
sec_firmware_support_hwrng(void)350 bool sec_firmware_support_hwrng(void)
351 {
352 #ifdef CONFIG_TFABOOT
353 	/* return true as TFA has one job ring reserved */
354 	return true;
355 #endif
356 	if (sec_firmware_addr & SEC_FIRMWARE_RUNNING) {
357 		return true;
358 	}
359 
360 	return false;
361 }
362 
363 /*
364  * sec_firmware_get_random - Get a random number from SEC Firmware
365  * @rand:		random number buffer to be filled
366  * @bytes:		Number of bytes of random number to be supported
367  * @eret:		-1 in case of error, 0 for success
368  */
sec_firmware_get_random(uint8_t * rand,int bytes)369 int sec_firmware_get_random(uint8_t *rand, int bytes)
370 {
371 	unsigned long long num;
372 	struct pt_regs regs;
373 	int param1;
374 
375 	if (!bytes || bytes > 8) {
376 		printf("Max Random bytes genration supported is 8\n");
377 		return -1;
378 	}
379 #define SIP_RNG_64 0xC200FF11
380 	regs.regs[0] = SIP_RNG_64;
381 
382 	if (bytes <= 4)
383 		param1 = 0;
384 	else
385 		param1 = 1;
386 	regs.regs[1] = param1;
387 
388 	smc_call(&regs);
389 
390 	if (regs.regs[0])
391 		return -1;
392 
393 	num = regs.regs[1];
394 	memcpy(rand, &num, bytes);
395 
396 	return 0;
397 }
398 
399 /*
400  * sec_firmware_init - Initialize the SEC Firmware
401  * @sec_firmware_img:	the SEC Firmware image address
402  * @eret_hold_l:	the address to hold exception return address low
403  * @eret_hold_h:	the address to hold exception return address high
404  * @loadable_l:		the address to hold loadable address low
405  * @loadable_h:		the address to hold loadable address high
406  */
sec_firmware_init(const void * sec_firmware_img,u32 * eret_hold_l,u32 * eret_hold_h,u32 * loadable_l,u32 * loadable_h)407 int sec_firmware_init(const void *sec_firmware_img,
408 			u32 *eret_hold_l,
409 			u32 *eret_hold_h,
410 			u32 *loadable_l,
411 			u32 *loadable_h)
412 {
413 	int ret;
414 
415 	if (!sec_firmware_is_valid(sec_firmware_img))
416 		return -EINVAL;
417 
418 	ret = sec_firmware_load_image(sec_firmware_img, loadable_l,
419 				      loadable_h);
420 	if (ret) {
421 		printf("SEC Firmware: Failed to load image\n");
422 		return ret;
423 	} else if (sec_firmware_addr & SEC_FIRMWARE_LOADED) {
424 		ret = sec_firmware_entry(eret_hold_l, eret_hold_h);
425 		if (ret) {
426 			printf("SEC Firmware: Failed to initialize\n");
427 			return ret;
428 		}
429 	}
430 
431 	debug("SEC Firmware: Return from SEC Firmware: current_el = %d\n",
432 	      current_el());
433 
434 	/*
435 	 * The PE will be turned into target EL when returned from
436 	 * SEC Firmware.
437 	 */
438 	if (current_el() != SEC_FIRMWARE_TARGET_EL)
439 		return -EACCES;
440 
441 	sec_firmware_addr |= SEC_FIRMWARE_RUNNING;
442 
443 	/* Set exception table and enable caches if it isn't EL3 */
444 	if (current_el() != 3) {
445 		c_runtime_cpu_setup();
446 		enable_caches();
447 	}
448 
449 	return 0;
450 }
451 
452 /*
453  * fdt_fix_kaslr - Add kalsr-seed node in Device tree
454  * @fdt:		Device tree
455  * @eret:		0 in case of error, 1 for success
456  */
fdt_fixup_kaslr(void * fdt)457 int fdt_fixup_kaslr(void *fdt)
458 {
459 	int nodeoffset;
460 	int err, ret = 0;
461 	u8 rand[8];
462 
463 #if defined(CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT)
464 	/* Check if random seed generation is  supported */
465 	if (sec_firmware_support_hwrng() == false) {
466 		printf("WARNING: SEC firmware not running, no kaslr-seed\n");
467 		return 0;
468 	}
469 
470 	ret = sec_firmware_get_random(rand, 8);
471 	if (ret < 0) {
472 		printf("WARNING: No random number to set kaslr-seed\n");
473 		return 0;
474 	}
475 
476 	err = fdt_check_header(fdt);
477 	if (err < 0) {
478 		printf("fdt_chosen: %s\n", fdt_strerror(err));
479 		return 0;
480 	}
481 
482 	/* find or create "/chosen" node. */
483 	nodeoffset = fdt_find_or_add_subnode(fdt, 0, "chosen");
484 	if (nodeoffset < 0)
485 		return 0;
486 
487 	err = fdt_setprop(fdt, nodeoffset, "kaslr-seed", rand,
488 				  sizeof(rand));
489 	if (err < 0) {
490 		printf("WARNING: can't set kaslr-seed %s.\n",
491 		       fdt_strerror(err));
492 		return 0;
493 	}
494 	ret = 1;
495 #endif
496 
497 	return ret;
498 }
499