xref: /openbmc/u-boot/examples/api/glue.c (revision d9b23e26) 
1 /*
2  * (C) Copyright 2007-2008 Semihalf, Rafal Jaworowski <raj@semihalf.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <linux/types.h>
9 #include <api_public.h>
10 
11 #include "glue.h"
12 
13 static int valid_sig(struct api_signature *sig)
14 {
15 	uint32_t checksum;
16 	struct api_signature s;
17 
18 	if (sig == NULL)
19 		return 0;
20 	/*
21 	 * Clear the checksum field (in the local copy) so as to calculate the
22 	 * CRC with the same initial contents as at the time when the sig was
23 	 * produced
24 	 */
25 	s = *sig;
26 	s.checksum = 0;
27 
28 	checksum = crc32(0, (unsigned char *)&s, sizeof(struct api_signature));
29 
30 	if (checksum != sig->checksum)
31 		return 0;
32 
33 	return 1;
34 }
35 
36 /*
37  * Searches for the U-Boot API signature
38  *
39  * returns 1/0 depending on found/not found result
40  */
41 int api_search_sig(struct api_signature **sig)
42 {
43 	unsigned char *sp;
44 	uint32_t search_start = 0;
45 	uint32_t search_end = 0;
46 
47 	if (sig == NULL)
48 		return 0;
49 
50 	if (search_hint == 0)
51 		search_hint = 255 * 1024 * 1024;
52 
53 	search_start = search_hint & ~0x000fffff;
54 	search_end = search_start + API_SEARCH_LEN - API_SIG_MAGLEN;
55 
56 	sp = (unsigned char *)search_start;
57 	while ((sp + API_SIG_MAGLEN) < (unsigned char *)search_end) {
58 		if (!memcmp(sp, API_SIG_MAGIC, API_SIG_MAGLEN)) {
59 			*sig = (struct api_signature *)sp;
60 			if (valid_sig(*sig))
61 				return 1;
62 		}
63 		sp += API_SIG_MAGLEN;
64 	}
65 
66 	*sig = NULL;
67 	return 0;
68 }
69 
70 /****************************************
71  *
72  * console
73  *
74  ****************************************/
75 
76 int ub_getc(void)
77 {
78 	int c;
79 
80 	if (!syscall(API_GETC, NULL, &c))
81 		return -1;
82 
83 	return c;
84 }
85 
86 int ub_tstc(void)
87 {
88 	int t;
89 
90 	if (!syscall(API_TSTC, NULL, &t))
91 		return -1;
92 
93 	return t;
94 }
95 
96 void ub_putc(char c)
97 {
98 	syscall(API_PUTC, NULL, &c);
99 }
100 
101 void ub_puts(const char *s)
102 {
103 	syscall(API_PUTS, NULL, s);
104 }
105 
106 /****************************************
107  *
108  * system
109  *
110  ****************************************/
111 
112 void ub_reset(void)
113 {
114 	syscall(API_RESET, NULL);
115 }
116 
117 static struct mem_region mr[UB_MAX_MR];
118 static struct sys_info si;
119 
120 struct sys_info * ub_get_sys_info(void)
121 {
122 	int err = 0;
123 
124 	memset(&si, 0, sizeof(struct sys_info));
125 	si.mr = mr;
126 	si.mr_no = UB_MAX_MR;
127 	memset(&mr, 0, sizeof(mr));
128 
129 	if (!syscall(API_GET_SYS_INFO, &err, &si))
130 		return NULL;
131 
132 	return ((err) ? NULL : &si);
133 }
134 
135 /****************************************
136  *
137  * timing
138  *
139  ****************************************/
140 
141 void ub_udelay(unsigned long usec)
142 {
143 	syscall(API_UDELAY, NULL, &usec);
144 }
145 
146 unsigned long ub_get_timer(unsigned long base)
147 {
148 	unsigned long cur;
149 
150 	if (!syscall(API_GET_TIMER, NULL, &cur, &base))
151 		return 0;
152 
153 	return cur;
154 }
155 
156 
157 /****************************************************************************
158  *
159  * devices
160  *
161  * Devices are identified by handles: numbers 0, 1, 2, ..., UB_MAX_DEV-1
162  *
163  ***************************************************************************/
164 
165 static struct device_info devices[UB_MAX_DEV];
166 
167 struct device_info * ub_dev_get(int i)
168 {
169 	return ((i < 0 || i >= UB_MAX_DEV) ? NULL : &devices[i]);
170 }
171 
172 /*
173  * Enumerates the devices: fills out device_info elements in the devices[]
174  * array.
175  *
176  * returns:		number of devices found
177  */
178 int ub_dev_enum(void)
179 {
180 	struct device_info *di;
181 	int n = 0;
182 
183 	memset(&devices, 0, sizeof(struct device_info) * UB_MAX_DEV);
184 	di = &devices[0];
185 
186 	if (!syscall(API_DEV_ENUM, NULL, di))
187 		return 0;
188 
189 	while (di->cookie != NULL) {
190 
191 		if (++n >= UB_MAX_DEV)
192 			break;
193 
194 		/* take another device_info */
195 		di++;
196 
197 		/* pass on the previous cookie */
198 		di->cookie = devices[n - 1].cookie;
199 
200 		if (!syscall(API_DEV_ENUM, NULL, di))
201 			return 0;
202 	}
203 
204 	return n;
205 }
206 
207 /*
208  * handle:	0-based id of the device
209  *
210  * returns:	0 when OK, err otherwise
211  */
212 int ub_dev_open(int handle)
213 {
214 	struct device_info *di;
215 	int err = 0;
216 
217 	if (handle < 0 || handle >= UB_MAX_DEV)
218 		return API_EINVAL;
219 
220 	di = &devices[handle];
221 
222 	if (!syscall(API_DEV_OPEN, &err, di))
223 		return -1;
224 
225 	return err;
226 }
227 
228 int ub_dev_close(int handle)
229 {
230 	struct device_info *di;
231 
232 	if (handle < 0 || handle >= UB_MAX_DEV)
233 		return API_EINVAL;
234 
235 	di = &devices[handle];
236 	if (!syscall(API_DEV_CLOSE, NULL, di))
237 		return -1;
238 
239 	return 0;
240 }
241 
242 /*
243  *
244  * Validates device for read/write, it has to:
245  *
246  * - have sane handle
247  * - be opened
248  *
249  * returns:	0/1 accordingly
250  */
251 static int dev_valid(int handle)
252 {
253 	if (handle < 0 || handle >= UB_MAX_DEV)
254 		return 0;
255 
256 	if (devices[handle].state != DEV_STA_OPEN)
257 		return 0;
258 
259 	return 1;
260 }
261 
262 static int dev_stor_valid(int handle)
263 {
264 	if (!dev_valid(handle))
265 		return 0;
266 
267 	if (!(devices[handle].type & DEV_TYP_STOR))
268 		return 0;
269 
270 	return 1;
271 }
272 
273 int ub_dev_read(int handle, void *buf, lbasize_t len, lbastart_t start,
274 		lbasize_t *rlen)
275 {
276 	struct device_info *di;
277 	lbasize_t act_len;
278 	int err = 0;
279 
280 	if (!dev_stor_valid(handle))
281 		return API_ENODEV;
282 
283 	di = &devices[handle];
284 	if (!syscall(API_DEV_READ, &err, di, buf, &len, &start, &act_len))
285 		return API_ESYSC;
286 
287 	if (!err && rlen)
288 		*rlen = act_len;
289 
290 	return err;
291 }
292 
293 static int dev_net_valid(int handle)
294 {
295 	if (!dev_valid(handle))
296 		return 0;
297 
298 	if (devices[handle].type != DEV_TYP_NET)
299 		return 0;
300 
301 	return 1;
302 }
303 
304 int ub_dev_recv(int handle, void *buf, int len, int *rlen)
305 {
306 	struct device_info *di;
307 	int err = 0, act_len;
308 
309 	if (!dev_net_valid(handle))
310 		return API_ENODEV;
311 
312 	di = &devices[handle];
313 	if (!syscall(API_DEV_READ, &err, di, buf, &len, &act_len))
314 		return API_ESYSC;
315 
316 	if (!err && rlen)
317 		*rlen = act_len;
318 
319 	 return (err);
320 }
321 
322 int ub_dev_send(int handle, void *buf, int len)
323 {
324 	struct device_info *di;
325 	int err = 0;
326 
327 	if (!dev_net_valid(handle))
328 		return API_ENODEV;
329 
330 	di = &devices[handle];
331 	if (!syscall(API_DEV_WRITE, &err, di, buf, &len))
332 		return API_ESYSC;
333 
334 	return err;
335 }
336 
337 /****************************************
338  *
339  * env vars
340  *
341  ****************************************/
342 
343 char * ub_env_get(const char *name)
344 {
345 	char *value;
346 
347 	if (!syscall(API_ENV_GET, NULL, name, &value))
348 		return NULL;
349 
350 	return value;
351 }
352 
353 void ub_env_set(const char *name, char *value)
354 {
355 	syscall(API_ENV_SET, NULL, name, value);
356 }
357 
358 static char env_name[256];
359 
360 const char * ub_env_enum(const char *last)
361 {
362 	const char *env, *str;
363 	int i;
364 
365 	env = NULL;
366 
367 	/*
368 	 * It's OK to pass only the name piece as last (and not the whole
369 	 * 'name=val' string), since the API_ENUM_ENV call uses envmatch()
370 	 * internally, which handles such case
371 	 */
372 	if (!syscall(API_ENV_ENUM, NULL, last, &env))
373 		return NULL;
374 
375 	if (!env)
376 		/* no more env. variables to enumerate */
377 		return NULL;
378 
379 	/* next enumerated env var */
380 	memset(env_name, 0, 256);
381 	for (i = 0, str = env; *str != '=' && *str != '\0';)
382 		env_name[i++] = *str++;
383 
384 	env_name[i] = '\0';
385 
386 	return env_name;
387 }
388 
389 /****************************************
390  *
391  * display
392  *
393  ****************************************/
394 
395 int ub_display_get_info(int type, struct display_info *di)
396 {
397 	int err = 0;
398 
399 	if (!syscall(API_DISPLAY_GET_INFO, &err, type, di))
400 		return API_ESYSC;
401 
402 	return err;
403 }
404 
405 int ub_display_draw_bitmap(ulong bitmap, int x, int y)
406 {
407 	int err = 0;
408 
409 	if (!syscall(API_DISPLAY_DRAW_BITMAP, &err, bitmap, x, y))
410 		return API_ESYSC;
411 
412 	return err;
413 }
414 
415 void ub_display_clear(void)
416 {
417 	syscall(API_DISPLAY_CLEAR, NULL);
418 }
419