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 <fdt_support.h>
10 #include <image.h>
11 #include <log.h>
12 #include <asm/cache.h>
13 #include <asm/global_data.h>
14 #include <asm/ptrace.h>
15 #include <linux/kernel.h>
16 #include <asm/io.h>
17 #include <asm/system.h>
18 #include <asm/types.h>
19 #include <asm/macro.h>
20 #include <asm/armv8/sec_firmware.h>
21 
22 DECLARE_GLOBAL_DATA_PTR;
23 extern void c_runtime_cpu_setup(void);
24 
25 #define SEC_FIRMWARE_LOADED	0x1
26 #define SEC_FIRMWARE_RUNNING	0x2
27 #define SEC_FIRMWARE_ADDR_MASK	(~0x3)
28 /*
29  * Secure firmware load addr
30  * Flags used: 0x1 secure firmware has been loaded to secure memory
31  *             0x2 secure firmware is running
32  */
33 phys_addr_t sec_firmware_addr;
34 
35 #ifndef SEC_FIRMWARE_FIT_IMAGE
36 #define SEC_FIRMWARE_FIT_IMAGE		"firmware"
37 #endif
38 #ifndef SEC_FIRMWARE_FIT_CNF_NAME
39 #define SEC_FIRMWARE_FIT_CNF_NAME	"config-1"
40 #endif
41 #ifndef SEC_FIRMWARE_TARGET_EL
42 #define SEC_FIRMWARE_TARGET_EL		2
43 #endif
44 
sec_firmware_get_data(const void * sec_firmware_img,const void ** data,size_t * size)45 static int sec_firmware_get_data(const void *sec_firmware_img,
46 				const void **data, size_t *size)
47 {
48 	int conf_node_off, fw_node_off;
49 	char *conf_node_name = NULL;
50 	char *desc;
51 	int ret;
52 
53 	conf_node_name = SEC_FIRMWARE_FIT_CNF_NAME;
54 
55 	conf_node_off = fit_conf_get_node(sec_firmware_img, conf_node_name);
56 	if (conf_node_off < 0) {
57 		printf("SEC Firmware: %s: no such config\n", conf_node_name);
58 		return -ENOENT;
59 	}
60 
61 	fw_node_off = fit_conf_get_prop_node(sec_firmware_img, conf_node_off,
62 			SEC_FIRMWARE_FIT_IMAGE);
63 	if (fw_node_off < 0) {
64 		printf("SEC Firmware: No '%s' in config\n",
65 		       SEC_FIRMWARE_FIT_IMAGE);
66 		return -ENOLINK;
67 	}
68 
69 	/* Verify secure firmware image */
70 	if (!(fit_image_verify(sec_firmware_img, fw_node_off))) {
71 		printf("SEC Firmware: Bad firmware image (bad CRC)\n");
72 		return -EINVAL;
73 	}
74 
75 	if (fit_image_get_data(sec_firmware_img, fw_node_off, data, size)) {
76 		printf("SEC Firmware: Can't get %s subimage data/size",
77 		       SEC_FIRMWARE_FIT_IMAGE);
78 		return -ENOENT;
79 	}
80 
81 	ret = fit_get_desc(sec_firmware_img, fw_node_off, &desc);
82 	if (ret)
83 		printf("SEC Firmware: Can't get description\n");
84 	else
85 		printf("%s\n", desc);
86 
87 	return ret;
88 }
89 
90 /*
91  * SEC Firmware FIT image parser checks if the image is in FIT
92  * format, verifies integrity of the image and calculates raw
93  * image address and size values.
94  *
95  * Returns 0 on success and a negative errno on error task fail.
96  */
sec_firmware_parse_image(const void * sec_firmware_img,const void ** raw_image_addr,size_t * raw_image_size)97 static int sec_firmware_parse_image(const void *sec_firmware_img,
98 					const void **raw_image_addr,
99 					size_t *raw_image_size)
100 {
101 	int ret;
102 
103 	ret = sec_firmware_get_data(sec_firmware_img, raw_image_addr,
104 					raw_image_size);
105 	if (ret)
106 		return ret;
107 
108 	debug("SEC Firmware: raw_image_addr = 0x%p, raw_image_size = 0x%lx\n",
109 	      *raw_image_addr, *raw_image_size);
110 
111 	return 0;
112 }
113 
114 /*
115  * SEC Firmware FIT image parser to check if any loadable is
116  * present. If present, verify integrity of the loadable and
117  * copy loadable to address provided in (loadable_h, loadable_l).
118  *
119  * Returns 0 on success and a negative errno on error task fail.
120  */
sec_firmware_check_copy_loadable(const void * sec_firmware_img,u32 * loadable_l,u32 * loadable_h)121 static int sec_firmware_check_copy_loadable(const void *sec_firmware_img,
122 					    u32 *loadable_l, u32 *loadable_h)
123 {
124 	phys_addr_t sec_firmware_loadable_addr = 0;
125 	int conf_node_off, ld_node_off, images;
126 	char *conf_node_name = NULL;
127 	const void *data;
128 	size_t size;
129 	ulong load;
130 	const char *name, *str, *type;
131 	int len;
132 
133 	conf_node_name = SEC_FIRMWARE_FIT_CNF_NAME;
134 
135 	conf_node_off = fit_conf_get_node(sec_firmware_img, conf_node_name);
136 	if (conf_node_off < 0) {
137 		printf("SEC Firmware: %s: no such config\n", conf_node_name);
138 		return -ENOENT;
139 	}
140 
141 	/* find the node holding the images information */
142 	images = fdt_path_offset(sec_firmware_img, FIT_IMAGES_PATH);
143 	if (images < 0) {
144 		printf("%s: Cannot find /images node: %d\n", __func__, images);
145 		return -1;
146 	}
147 
148 	type = FIT_LOADABLE_PROP;
149 
150 	name = fdt_getprop(sec_firmware_img, conf_node_off, type, &len);
151 	if (!name) {
152 		/* Loadables not present */
153 		return 0;
154 	}
155 
156 	printf("SEC Firmware: '%s' present in config\n", type);
157 
158 	for (str = name; str && ((str - name) < len);
159 	     str = strchr(str, '\0') + 1) {
160 		printf("%s: '%s'\n", type, str);
161 		ld_node_off = fdt_subnode_offset(sec_firmware_img, images, str);
162 		if (ld_node_off < 0) {
163 			printf("cannot find image node '%s': %d\n", str,
164 			       ld_node_off);
165 			return -EINVAL;
166 		}
167 
168 		/* Verify secure firmware image */
169 		if (!(fit_image_verify(sec_firmware_img, ld_node_off))) {
170 			printf("SEC Loadable: Bad loadable image (bad CRC)\n");
171 			return -EINVAL;
172 		}
173 
174 		if (fit_image_get_data(sec_firmware_img, ld_node_off,
175 				       &data, &size)) {
176 			printf("SEC Loadable: Can't get subimage data/size");
177 			return -ENOENT;
178 		}
179 
180 		/* Get load address, treated as load offset to secure memory */
181 		if (fit_image_get_load(sec_firmware_img, ld_node_off, &load)) {
182 			printf("SEC Loadable: Can't get subimage load");
183 			return -ENOENT;
184 		}
185 
186 		/* Compute load address for loadable in secure memory */
187 		sec_firmware_loadable_addr = (sec_firmware_addr -
188 						gd->arch.tlb_size) + load;
189 
190 		/* Copy loadable to secure memory and flush dcache */
191 		debug("%s copied to address 0x%p\n",
192 		      FIT_LOADABLE_PROP, (void *)sec_firmware_loadable_addr);
193 		memcpy((void *)sec_firmware_loadable_addr, data, size);
194 		flush_dcache_range(sec_firmware_loadable_addr,
195 				   sec_firmware_loadable_addr + size);
196 
197 		/* Populate loadable address only for Trusted OS */
198 		if (!strcmp(str, "trustedOS@1")) {
199 			/*
200 			 * Populate address ptrs for loadable image with
201 			 * loadbale addr
202 			 */
203 			out_le32(loadable_l, (sec_firmware_loadable_addr &
204 					      WORD_MASK));
205 			out_le32(loadable_h, (sec_firmware_loadable_addr >>
206 					      WORD_SHIFT));
207 		}
208 	}
209 
210 	return 0;
211 }
212 
sec_firmware_copy_image(const char * title,u64 image_addr,u32 image_size,u64 sec_firmware)213 static int sec_firmware_copy_image(const char *title,
214 			 u64 image_addr, u32 image_size, u64 sec_firmware)
215 {
216 	debug("%s copied to address 0x%p\n", title, (void *)sec_firmware);
217 	memcpy((void *)sec_firmware, (void *)image_addr, image_size);
218 	flush_dcache_range(sec_firmware, sec_firmware + image_size);
219 
220 	return 0;
221 }
222 
223 /*
224  * This function will parse the SEC Firmware image, and then load it
225  * to secure memory. Also load any loadable if present along with SEC
226  * Firmware image.
227  */
sec_firmware_load_image(const void * sec_firmware_img,u32 * loadable_l,u32 * loadable_h)228 static int sec_firmware_load_image(const void *sec_firmware_img,
229 				   u32 *loadable_l, u32 *loadable_h)
230 {
231 	const void *raw_image_addr;
232 	size_t raw_image_size = 0;
233 	int ret;
234 
235 	/*
236 	 * The Excetpion Level must be EL3 to load and initialize
237 	 * the SEC Firmware.
238 	 */
239 	if (current_el() != 3) {
240 		ret = -EACCES;
241 		goto out;
242 	}
243 
244 #ifdef CONFIG_SYS_MEM_RESERVE_SECURE
245 	/*
246 	 * The SEC Firmware must be stored in secure memory.
247 	 * Append SEC Firmware to secure mmu table.
248 	 */
249 	if (!(gd->arch.secure_ram & MEM_RESERVE_SECURE_MAINTAINED)) {
250 		ret = -ENXIO;
251 		goto out;
252 	}
253 
254 	sec_firmware_addr = (gd->arch.secure_ram & MEM_RESERVE_SECURE_ADDR_MASK) +
255 			gd->arch.tlb_size;
256 #else
257 #error "The CONFIG_SYS_MEM_RESERVE_SECURE must be defined when enabled SEC Firmware support"
258 #endif
259 
260 	/* Align SEC Firmware base address to 4K */
261 	sec_firmware_addr = (sec_firmware_addr + 0xfff) & ~0xfff;
262 	debug("SEC Firmware: Load address: 0x%llx\n",
263 	      sec_firmware_addr & SEC_FIRMWARE_ADDR_MASK);
264 
265 	ret = sec_firmware_parse_image(sec_firmware_img, &raw_image_addr,
266 			&raw_image_size);
267 	if (ret)
268 		goto out;
269 
270 	/* TODO:
271 	 * Check if the end addr of SEC Firmware has been extend the secure
272 	 * memory.
273 	 */
274 
275 	/* Copy the secure firmware to secure memory */
276 	ret = sec_firmware_copy_image("SEC Firmware", (u64)raw_image_addr,
277 			raw_image_size, sec_firmware_addr &
278 			SEC_FIRMWARE_ADDR_MASK);
279 	if (ret)
280 		goto out;
281 
282 	/*
283 	 * Check if any loadable are present along with firmware image, if
284 	 * present load them.
285 	 */
286 	ret = sec_firmware_check_copy_loadable(sec_firmware_img, loadable_l,
287 					       loadable_h);
288 	if (ret)
289 		goto out;
290 
291 	sec_firmware_addr |= SEC_FIRMWARE_LOADED;
292 	debug("SEC Firmware: Entry point: 0x%llx\n",
293 	      sec_firmware_addr & SEC_FIRMWARE_ADDR_MASK);
294 
295 	return 0;
296 
297 out:
298 	printf("SEC Firmware: error (%d)\n", ret);
299 	sec_firmware_addr = 0;
300 
301 	return ret;
302 }
303 
sec_firmware_entry(u32 * eret_hold_l,u32 * eret_hold_h)304 static int sec_firmware_entry(u32 *eret_hold_l, u32 *eret_hold_h)
305 {
306 	const void *entry = (void *)(sec_firmware_addr &
307 				SEC_FIRMWARE_ADDR_MASK);
308 
309 	return _sec_firmware_entry(entry, eret_hold_l, eret_hold_h);
310 }
311 
312 /* Check the secure firmware FIT image */
sec_firmware_is_valid(const void * sec_firmware_img)313 __weak bool sec_firmware_is_valid(const void *sec_firmware_img)
314 {
315 	if (fdt_check_header(sec_firmware_img)) {
316 		printf("SEC Firmware: Bad firmware image (not a FIT image)\n");
317 		return false;
318 	}
319 
320 	if (fit_check_format(sec_firmware_img, IMAGE_SIZE_INVAL)) {
321 		printf("SEC Firmware: Bad firmware image (bad FIT header)\n");
322 		return false;
323 	}
324 
325 	return true;
326 }
327 
328 #ifdef CONFIG_SEC_FIRMWARE_ARMV8_PSCI
329 /*
330  * The PSCI_VERSION function is added from PSCI v0.2. When the PSCI
331  * v0.1 received this function, the NOT_SUPPORTED (0xffff_ffff) error
332  * number will be returned according to SMC Calling Conventions. But
333  * when getting the NOT_SUPPORTED error number, we cannot ensure if
334  * the PSCI version is v0.1 or other error occurred. So, PSCI v0.1
335  * won't be supported by this framework.
336  * And if the secure firmware isn't running, return NOT_SUPPORTED.
337  *
338  * The return value on success is PSCI version in format
339  * major[31:16]:minor[15:0].
340  */
sec_firmware_support_psci_version(void)341 unsigned int sec_firmware_support_psci_version(void)
342 {
343 	if (current_el() == SEC_FIRMWARE_TARGET_EL)
344 		return _sec_firmware_support_psci_version();
345 
346 	return PSCI_INVALID_VER;
347 }
348 #endif
349 
350 /*
351  * Check with sec_firmware if it supports random number generation
352  * via HW RNG
353  *
354  * The return value will be true if it is supported
355  */
sec_firmware_support_hwrng(void)356 bool sec_firmware_support_hwrng(void)
357 {
358 #ifdef CONFIG_TFABOOT
359 	/* return true as TFA has one job ring reserved */
360 	return true;
361 #endif
362 	if (sec_firmware_addr & SEC_FIRMWARE_RUNNING) {
363 		return true;
364 	}
365 
366 	return false;
367 }
368 
369 /*
370  * sec_firmware_get_random - Get a random number from SEC Firmware
371  * @rand:		random number buffer to be filled
372  * @bytes:		Number of bytes of random number to be supported
373  * @eret:		-1 in case of error, 0 for success
374  */
sec_firmware_get_random(uint8_t * rand,int bytes)375 int sec_firmware_get_random(uint8_t *rand, int bytes)
376 {
377 	unsigned long long num;
378 	struct pt_regs regs;
379 	int param1;
380 
381 	if (!bytes || bytes > 8) {
382 		printf("Max Random bytes genration supported is 8\n");
383 		return -1;
384 	}
385 #define SIP_RNG_64 0xC200FF11
386 	regs.regs[0] = SIP_RNG_64;
387 
388 	if (bytes <= 4)
389 		param1 = 0;
390 	else
391 		param1 = 1;
392 	regs.regs[1] = param1;
393 
394 	smc_call(&regs);
395 
396 	if (regs.regs[0])
397 		return -1;
398 
399 	num = regs.regs[1];
400 	memcpy(rand, &num, bytes);
401 
402 	return 0;
403 }
404 
405 /*
406  * sec_firmware_init - Initialize the SEC Firmware
407  * @sec_firmware_img:	the SEC Firmware image address
408  * @eret_hold_l:	the address to hold exception return address low
409  * @eret_hold_h:	the address to hold exception return address high
410  * @loadable_l:		the address to hold loadable address low
411  * @loadable_h:		the address to hold loadable address high
412  */
sec_firmware_init(const void * sec_firmware_img,u32 * eret_hold_l,u32 * eret_hold_h,u32 * loadable_l,u32 * loadable_h)413 int sec_firmware_init(const void *sec_firmware_img,
414 			u32 *eret_hold_l,
415 			u32 *eret_hold_h,
416 			u32 *loadable_l,
417 			u32 *loadable_h)
418 {
419 	int ret;
420 
421 	if (!sec_firmware_is_valid(sec_firmware_img))
422 		return -EINVAL;
423 
424 	ret = sec_firmware_load_image(sec_firmware_img, loadable_l,
425 				      loadable_h);
426 	if (ret) {
427 		printf("SEC Firmware: Failed to load image\n");
428 		return ret;
429 	} else if (sec_firmware_addr & SEC_FIRMWARE_LOADED) {
430 		ret = sec_firmware_entry(eret_hold_l, eret_hold_h);
431 		if (ret) {
432 			printf("SEC Firmware: Failed to initialize\n");
433 			return ret;
434 		}
435 	}
436 
437 	debug("SEC Firmware: Return from SEC Firmware: current_el = %d\n",
438 	      current_el());
439 
440 	/*
441 	 * The PE will be turned into target EL when returned from
442 	 * SEC Firmware.
443 	 */
444 	if (current_el() != SEC_FIRMWARE_TARGET_EL)
445 		return -EACCES;
446 
447 	sec_firmware_addr |= SEC_FIRMWARE_RUNNING;
448 
449 	/* Set exception table and enable caches if it isn't EL3 */
450 	if (current_el() != 3) {
451 		c_runtime_cpu_setup();
452 		enable_caches();
453 	}
454 
455 	return 0;
456 }
457 
458 /*
459  * fdt_fix_kaslr - Add kalsr-seed node in Device tree
460  * @fdt:		Device tree
461  * @eret:		0 in case of error, 1 for success
462  */
fdt_fixup_kaslr(void * fdt)463 int fdt_fixup_kaslr(void *fdt)
464 {
465 	int nodeoffset;
466 	int err, ret = 0;
467 	u8 rand[8];
468 
469 #if defined(CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT)
470 	/* Check if random seed generation is  supported */
471 	if (sec_firmware_support_hwrng() == false) {
472 		printf("WARNING: SEC firmware not running, no kaslr-seed\n");
473 		return 0;
474 	}
475 
476 	ret = sec_firmware_get_random(rand, 8);
477 	if (ret < 0) {
478 		printf("WARNING: No random number to set kaslr-seed\n");
479 		return 0;
480 	}
481 
482 	err = fdt_check_header(fdt);
483 	if (err < 0) {
484 		printf("fdt_chosen: %s\n", fdt_strerror(err));
485 		return 0;
486 	}
487 
488 	/* find or create "/chosen" node. */
489 	nodeoffset = fdt_find_or_add_subnode(fdt, 0, "chosen");
490 	if (nodeoffset < 0)
491 		return 0;
492 
493 	err = fdt_setprop(fdt, nodeoffset, "kaslr-seed", rand,
494 				  sizeof(rand));
495 	if (err < 0) {
496 		printf("WARNING: can't set kaslr-seed %s.\n",
497 		       fdt_strerror(err));
498 		return 0;
499 	}
500 	ret = 1;
501 #endif
502 
503 	return ret;
504 }
505