xref: /openbmc/u-boot/examples/api/glue.c (revision 87a62bce) 
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2007-2008 Semihalf, Rafal Jaworowski <raj@semihalf.com>
4  */
5 
6 #include <common.h>
7 #include <linux/types.h>
8 #include <api_public.h>
9 
10 #include "glue.h"
11 
12 static int valid_sig(struct api_signature *sig)
13 {
14 	uint32_t checksum;
15 	struct api_signature s;
16 
17 	if (sig == NULL)
18 		return 0;
19 	/*
20 	 * Clear the checksum field (in the local copy) so as to calculate the
21 	 * CRC with the same initial contents as at the time when the sig was
22 	 * produced
23 	 */
24 	s = *sig;
25 	s.checksum = 0;
26 
27 	checksum = crc32(0, (unsigned char *)&s, sizeof(struct api_signature));
28 
29 	if (checksum != sig->checksum)
30 		return 0;
31 
32 	return 1;
33 }
34 
35 /*
36  * Searches for the U-Boot API signature
37  *
38  * returns 1/0 depending on found/not found result
39  */
40 int api_search_sig(struct api_signature **sig)
41 {
42 	unsigned char *sp;
43 	uint32_t search_start = 0;
44 	uint32_t search_end = 0;
45 
46 	if (sig == NULL)
47 		return 0;
48 
49 	if (search_hint == 0)
50 		search_hint = 255 * 1024 * 1024;
51 
52 	search_start = search_hint & ~0x000fffff;
53 	search_end = search_start + API_SEARCH_LEN - API_SIG_MAGLEN;
54 
55 	sp = (unsigned char *)search_start;
56 	while ((sp + API_SIG_MAGLEN) < (unsigned char *)search_end) {
57 		if (!memcmp(sp, API_SIG_MAGIC, API_SIG_MAGLEN)) {
58 			*sig = (struct api_signature *)sp;
59 			if (valid_sig(*sig))
60 				return 1;
61 		}
62 		sp += API_SIG_MAGLEN;
63 	}
64 
65 	*sig = NULL;
66 	return 0;
67 }
68 
69 /****************************************
70  *
71  * console
72  *
73  ****************************************/
74 
75 int ub_getc(void)
76 {
77 	int c;
78 
79 	if (!syscall(API_GETC, NULL, &c))
80 		return -1;
81 
82 	return c;
83 }
84 
85 int ub_tstc(void)
86 {
87 	int t;
88 
89 	if (!syscall(API_TSTC, NULL, &t))
90 		return -1;
91 
92 	return t;
93 }
94 
95 void ub_putc(char c)
96 {
97 	syscall(API_PUTC, NULL, &c);
98 }
99 
100 void ub_puts(const char *s)
101 {
102 	syscall(API_PUTS, NULL, s);
103 }
104 
105 /****************************************
106  *
107  * system
108  *
109  ****************************************/
110 
111 void ub_reset(void)
112 {
113 	syscall(API_RESET, NULL);
114 }
115 
116 static struct mem_region mr[UB_MAX_MR];
117 static struct sys_info si;
118 
119 struct sys_info * ub_get_sys_info(void)
120 {
121 	int err = 0;
122 
123 	memset(&si, 0, sizeof(struct sys_info));
124 	si.mr = mr;
125 	si.mr_no = UB_MAX_MR;
126 	memset(&mr, 0, sizeof(mr));
127 
128 	if (!syscall(API_GET_SYS_INFO, &err, &si))
129 		return NULL;
130 
131 	return ((err) ? NULL : &si);
132 }
133 
134 /****************************************
135  *
136  * timing
137  *
138  ****************************************/
139 
140 void ub_udelay(unsigned long usec)
141 {
142 	syscall(API_UDELAY, NULL, &usec);
143 }
144 
145 unsigned long ub_get_timer(unsigned long base)
146 {
147 	unsigned long cur;
148 
149 	if (!syscall(API_GET_TIMER, NULL, &cur, &base))
150 		return 0;
151 
152 	return cur;
153 }
154 
155 
156 /****************************************************************************
157  *
158  * devices
159  *
160  * Devices are identified by handles: numbers 0, 1, 2, ..., UB_MAX_DEV-1
161  *
162  ***************************************************************************/
163 
164 static struct device_info devices[UB_MAX_DEV];
165 
166 struct device_info * ub_dev_get(int i)
167 {
168 	return ((i < 0 || i >= UB_MAX_DEV) ? NULL : &devices[i]);
169 }
170 
171 /*
172  * Enumerates the devices: fills out device_info elements in the devices[]
173  * array.
174  *
175  * returns:		number of devices found
176  */
177 int ub_dev_enum(void)
178 {
179 	struct device_info *di;
180 	int n = 0;
181 
182 	memset(&devices, 0, sizeof(struct device_info) * UB_MAX_DEV);
183 	di = &devices[0];
184 
185 	if (!syscall(API_DEV_ENUM, NULL, di))
186 		return 0;
187 
188 	while (di->cookie != NULL) {
189 
190 		if (++n >= UB_MAX_DEV)
191 			break;
192 
193 		/* take another device_info */
194 		di++;
195 
196 		/* pass on the previous cookie */
197 		di->cookie = devices[n - 1].cookie;
198 
199 		if (!syscall(API_DEV_ENUM, NULL, di))
200 			return 0;
201 	}
202 
203 	return n;
204 }
205 
206 /*
207  * handle:	0-based id of the device
208  *
209  * returns:	0 when OK, err otherwise
210  */
211 int ub_dev_open(int handle)
212 {
213 	struct device_info *di;
214 	int err = 0;
215 
216 	if (handle < 0 || handle >= UB_MAX_DEV)
217 		return API_EINVAL;
218 
219 	di = &devices[handle];
220 
221 	if (!syscall(API_DEV_OPEN, &err, di))
222 		return -1;
223 
224 	return err;
225 }
226 
227 int ub_dev_close(int handle)
228 {
229 	struct device_info *di;
230 
231 	if (handle < 0 || handle >= UB_MAX_DEV)
232 		return API_EINVAL;
233 
234 	di = &devices[handle];
235 	if (!syscall(API_DEV_CLOSE, NULL, di))
236 		return -1;
237 
238 	return 0;
239 }
240 
241 /*
242  *
243  * Validates device for read/write, it has to:
244  *
245  * - have sane handle
246  * - be opened
247  *
248  * returns:	0/1 accordingly
249  */
250 static int dev_valid(int handle)
251 {
252 	if (handle < 0 || handle >= UB_MAX_DEV)
253 		return 0;
254 
255 	if (devices[handle].state != DEV_STA_OPEN)
256 		return 0;
257 
258 	return 1;
259 }
260 
261 static int dev_stor_valid(int handle)
262 {
263 	if (!dev_valid(handle))
264 		return 0;
265 
266 	if (!(devices[handle].type & DEV_TYP_STOR))
267 		return 0;
268 
269 	return 1;
270 }
271 
272 int ub_dev_read(int handle, void *buf, lbasize_t len, lbastart_t start,
273 		lbasize_t *rlen)
274 {
275 	struct device_info *di;
276 	lbasize_t act_len;
277 	int err = 0;
278 
279 	if (!dev_stor_valid(handle))
280 		return API_ENODEV;
281 
282 	di = &devices[handle];
283 	if (!syscall(API_DEV_READ, &err, di, buf, &len, &start, &act_len))
284 		return API_ESYSC;
285 
286 	if (!err && rlen)
287 		*rlen = act_len;
288 
289 	return err;
290 }
291 
292 static int dev_net_valid(int handle)
293 {
294 	if (!dev_valid(handle))
295 		return 0;
296 
297 	if (devices[handle].type != DEV_TYP_NET)
298 		return 0;
299 
300 	return 1;
301 }
302 
303 int ub_dev_recv(int handle, void *buf, int len, int *rlen)
304 {
305 	struct device_info *di;
306 	int err = 0, act_len;
307 
308 	if (!dev_net_valid(handle))
309 		return API_ENODEV;
310 
311 	di = &devices[handle];
312 	if (!syscall(API_DEV_READ, &err, di, buf, &len, &act_len))
313 		return API_ESYSC;
314 
315 	if (!err && rlen)
316 		*rlen = act_len;
317 
318 	 return (err);
319 }
320 
321 int ub_dev_send(int handle, void *buf, int len)
322 {
323 	struct device_info *di;
324 	int err = 0;
325 
326 	if (!dev_net_valid(handle))
327 		return API_ENODEV;
328 
329 	di = &devices[handle];
330 	if (!syscall(API_DEV_WRITE, &err, di, buf, &len))
331 		return API_ESYSC;
332 
333 	return err;
334 }
335 
336 /****************************************
337  *
338  * env vars
339  *
340  ****************************************/
341 
342 char * ub_env_get(const char *name)
343 {
344 	char *value;
345 
346 	if (!syscall(API_ENV_GET, NULL, name, &value))
347 		return NULL;
348 
349 	return value;
350 }
351 
352 void ub_env_set(const char *name, char *value)
353 {
354 	syscall(API_ENV_SET, NULL, name, value);
355 }
356 
357 static char env_name[256];
358 
359 const char * ub_env_enum(const char *last)
360 {
361 	const char *env, *str;
362 	int i;
363 
364 	env = NULL;
365 
366 	/*
367 	 * It's OK to pass only the name piece as last (and not the whole
368 	 * 'name=val' string), since the API_ENUM_ENV call uses envmatch()
369 	 * internally, which handles such case
370 	 */
371 	if (!syscall(API_ENV_ENUM, NULL, last, &env))
372 		return NULL;
373 
374 	if (!env)
375 		/* no more env. variables to enumerate */
376 		return NULL;
377 
378 	/* next enumerated env var */
379 	memset(env_name, 0, 256);
380 	for (i = 0, str = env; *str != '=' && *str != '\0';)
381 		env_name[i++] = *str++;
382 
383 	env_name[i] = '\0';
384 
385 	return env_name;
386 }
387 
388 /****************************************
389  *
390  * display
391  *
392  ****************************************/
393 
394 int ub_display_get_info(int type, struct display_info *di)
395 {
396 	int err = 0;
397 
398 	if (!syscall(API_DISPLAY_GET_INFO, &err, type, di))
399 		return API_ESYSC;
400 
401 	return err;
402 }
403 
404 int ub_display_draw_bitmap(ulong bitmap, int x, int y)
405 {
406 	int err = 0;
407 
408 	if (!syscall(API_DISPLAY_DRAW_BITMAP, &err, bitmap, x, y))
409 		return API_ESYSC;
410 
411 	return err;
412 }
413 
414 void ub_display_clear(void)
415 {
416 	syscall(API_DISPLAY_CLEAR, NULL);
417 }
418 
419 __weak void *memcpy(void *dest, const void *src, size_t size)
420 {
421 	unsigned char *dptr = dest;
422 	const unsigned char *ptr = src;
423 	const unsigned char *end = src + size;
424 
425 	while (ptr < end)
426 		*dptr++ = *ptr++;
427 
428 	return dest;
429 }
430