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      1 // SPDX-License-Identifier: GPL-2.0+
      2 /*
      3  * (C) Copyright 2007 Semihalf
      4  *
      5  * Written by: Rafal Jaworowski <raj (at) semihalf.com>
      6  */
      7 
      8 #include <config.h>
      9 #include <command.h>
     10 #include <common.h>
     11 #include <malloc.h>
     12 #include <environment.h>
     13 #include <linux/types.h>
     14 #include <api_public.h>
     15 
     16 #include "api_private.h"
     17 
     18 #define DEBUG
     19 #undef DEBUG
     20 
     21 /*****************************************************************************
     22  *
     23  * This is the API core.
     24  *
     25  * API_ functions are part of U-Boot code and constitute the lowest level
     26  * calls:
     27  *
     28  *  - they know what values they need as arguments
     29  *  - their direct return value pertains to the API_ "shell" itself (0 on
     30  *    success, some error code otherwise)
     31  *  - if the call returns a value it is buried within arguments
     32  *
     33  ****************************************************************************/
     34 
     35 #ifdef DEBUG
     36 #define debugf(fmt, args...) do { printf("%s(): ", __func__); printf(fmt, ##args); } while (0)
     37 #else
     38 #define debugf(fmt, args...)
     39 #endif
     40 
     41 typedef	int (*cfp_t)(va_list argp);
     42 
     43 static int calls_no;
     44 
     45 /*
     46  * pseudo signature:
     47  *
     48  * int API_getc(int *c)
     49  */
     50 static int API_getc(va_list ap)
     51 {
     52 	int *c;
     53 
     54 	if ((c = (int *)va_arg(ap, uintptr_t)) == NULL)
     55 		return API_EINVAL;
     56 
     57 	*c = getc();
     58 	return 0;
     59 }
     60 
     61 /*
     62  * pseudo signature:
     63  *
     64  * int API_tstc(int *c)
     65  */
     66 static int API_tstc(va_list ap)
     67 {
     68 	int *t;
     69 
     70 	if ((t = (int *)va_arg(ap, uintptr_t)) == NULL)
     71 		return API_EINVAL;
     72 
     73 	*t = tstc();
     74 	return 0;
     75 }
     76 
     77 /*
     78  * pseudo signature:
     79  *
     80  * int API_putc(char *ch)
     81  */
     82 static int API_putc(va_list ap)
     83 {
     84 	char *c;
     85 
     86 	if ((c = (char *)va_arg(ap, uintptr_t)) == NULL)
     87 		return API_EINVAL;
     88 
     89 	putc(*c);
     90 	return 0;
     91 }
     92 
     93 /*
     94  * pseudo signature:
     95  *
     96  * int API_puts(char **s)
     97  */
     98 static int API_puts(va_list ap)
     99 {
    100 	char *s;
    101 
    102 	if ((s = (char *)va_arg(ap, uintptr_t)) == NULL)
    103 		return API_EINVAL;
    104 
    105 	puts(s);
    106 	return 0;
    107 }
    108 
    109 /*
    110  * pseudo signature:
    111  *
    112  * int API_reset(void)
    113  */
    114 static int API_reset(va_list ap)
    115 {
    116 	do_reset(NULL, 0, 0, NULL);
    117 
    118 	/* NOT REACHED */
    119 	return 0;
    120 }
    121 
    122 /*
    123  * pseudo signature:
    124  *
    125  * int API_get_sys_info(struct sys_info *si)
    126  *
    127  * fill out the sys_info struct containing selected parameters about the
    128  * machine
    129  */
    130 static int API_get_sys_info(va_list ap)
    131 {
    132 	struct sys_info *si;
    133 
    134 	si = (struct sys_info *)va_arg(ap, uintptr_t);
    135 	if (si == NULL)
    136 		return API_ENOMEM;
    137 
    138 	return (platform_sys_info(si)) ? 0 : API_ENODEV;
    139 }
    140 
    141 /*
    142  * pseudo signature:
    143  *
    144  * int API_udelay(unsigned long *udelay)
    145  */
    146 static int API_udelay(va_list ap)
    147 {
    148 	unsigned long *d;
    149 
    150 	if ((d = (unsigned long *)va_arg(ap, unsigned long)) == NULL)
    151 		return API_EINVAL;
    152 
    153 	udelay(*d);
    154 	return 0;
    155 }
    156 
    157 /*
    158  * pseudo signature:
    159  *
    160  * int API_get_timer(unsigned long *current, unsigned long *base)
    161  */
    162 static int API_get_timer(va_list ap)
    163 {
    164 	unsigned long *base, *cur;
    165 
    166 	cur = (unsigned long *)va_arg(ap, unsigned long);
    167 	if (cur == NULL)
    168 		return API_EINVAL;
    169 
    170 	base = (unsigned long *)va_arg(ap, unsigned long);
    171 	if (base == NULL)
    172 		return API_EINVAL;
    173 
    174 	*cur = get_timer(*base);
    175 	return 0;
    176 }
    177 
    178 
    179 /*****************************************************************************
    180  *
    181  * pseudo signature:
    182  *
    183  * int API_dev_enum(struct device_info *)
    184  *
    185  *
    186  * cookies uniqely identify the previously enumerated device instance and
    187  * provide a hint for what to inspect in current enum iteration:
    188  *
    189  *   - net: &eth_device struct address from list pointed to by eth_devices
    190  *
    191  *   - storage: struct blk_desc struct address from &ide_dev_desc[n],
    192  *     &scsi_dev_desc[n] and similar tables
    193  *
    194  ****************************************************************************/
    195 
    196 static int API_dev_enum(va_list ap)
    197 {
    198 	struct device_info *di;
    199 
    200 	/* arg is ptr to the device_info struct we are going to fill out */
    201 	di = (struct device_info *)va_arg(ap, uintptr_t);
    202 	if (di == NULL)
    203 		return API_EINVAL;
    204 
    205 	if (di->cookie == NULL) {
    206 		/* start over - clean up enumeration */
    207 		dev_enum_reset();	/* XXX shouldn't the name contain 'stor'? */
    208 		debugf("RESTART ENUM\n");
    209 
    210 		/* net device enumeration first */
    211 		if (dev_enum_net(di))
    212 			return 0;
    213 	}
    214 
    215 	/*
    216 	 * The hidden assumption is there can only be one active network
    217 	 * device and it is identified upon enumeration (re)start, so there's
    218 	 * no point in trying to find network devices in other cases than the
    219 	 * (re)start and hence the 'next' device can only be storage
    220 	 */
    221 	if (!dev_enum_storage(di))
    222 		/* make sure we mark there are no more devices */
    223 		di->cookie = NULL;
    224 
    225 	return 0;
    226 }
    227 
    228 
    229 static int API_dev_open(va_list ap)
    230 {
    231 	struct device_info *di;
    232 	int err = 0;
    233 
    234 	/* arg is ptr to the device_info struct */
    235 	di = (struct device_info *)va_arg(ap, uintptr_t);
    236 	if (di == NULL)
    237 		return API_EINVAL;
    238 
    239 	/* Allow only one consumer of the device at a time */
    240 	if (di->state == DEV_STA_OPEN)
    241 		return API_EBUSY;
    242 
    243 	if (di->cookie == NULL)
    244 		return API_ENODEV;
    245 
    246 	if (di->type & DEV_TYP_STOR)
    247 		err = dev_open_stor(di->cookie);
    248 
    249 	else if (di->type & DEV_TYP_NET)
    250 		err = dev_open_net(di->cookie);
    251 	else
    252 		err = API_ENODEV;
    253 
    254 	if (!err)
    255 		di->state = DEV_STA_OPEN;
    256 
    257 	return err;
    258 }
    259 
    260 
    261 static int API_dev_close(va_list ap)
    262 {
    263 	struct device_info *di;
    264 	int err = 0;
    265 
    266 	/* arg is ptr to the device_info struct */
    267 	di = (struct device_info *)va_arg(ap, uintptr_t);
    268 	if (di == NULL)
    269 		return API_EINVAL;
    270 
    271 	if (di->state == DEV_STA_CLOSED)
    272 		return 0;
    273 
    274 	if (di->cookie == NULL)
    275 		return API_ENODEV;
    276 
    277 	if (di->type & DEV_TYP_STOR)
    278 		err = dev_close_stor(di->cookie);
    279 
    280 	else if (di->type & DEV_TYP_NET)
    281 		err = dev_close_net(di->cookie);
    282 	else
    283 		/*
    284 		 * In case of unknown device we cannot change its state, so
    285 		 * only return error code
    286 		 */
    287 		err = API_ENODEV;
    288 
    289 	if (!err)
    290 		di->state = DEV_STA_CLOSED;
    291 
    292 	return err;
    293 }
    294 
    295 
    296 /*
    297  * Notice: this is for sending network packets only, as U-Boot does not
    298  * support writing to storage at the moment (12.2007)
    299  *
    300  * pseudo signature:
    301  *
    302  * int API_dev_write(
    303  *	struct device_info *di,
    304  *	void *buf,
    305  *	int *len
    306  * )
    307  *
    308  * buf:	ptr to buffer from where to get the data to send
    309  *
    310  * len: length of packet to be sent (in bytes)
    311  *
    312  */
    313 static int API_dev_write(va_list ap)
    314 {
    315 	struct device_info *di;
    316 	void *buf;
    317 	int *len;
    318 	int err = 0;
    319 
    320 	/* 1. arg is ptr to the device_info struct */
    321 	di = (struct device_info *)va_arg(ap, uintptr_t);
    322 	if (di == NULL)
    323 		return API_EINVAL;
    324 
    325 	/* XXX should we check if device is open? i.e. the ->state ? */
    326 
    327 	if (di->cookie == NULL)
    328 		return API_ENODEV;
    329 
    330 	/* 2. arg is ptr to buffer from where to get data to write */
    331 	buf = (void *)va_arg(ap, uintptr_t);
    332 	if (buf == NULL)
    333 		return API_EINVAL;
    334 
    335 	/* 3. arg is length of buffer */
    336 	len = (int *)va_arg(ap, uintptr_t);
    337 	if (len == NULL)
    338 		return API_EINVAL;
    339 	if (*len <= 0)
    340 		return API_EINVAL;
    341 
    342 	if (di->type & DEV_TYP_STOR)
    343 		/*
    344 		 * write to storage is currently not supported by U-Boot:
    345 		 * no storage device implements block_write() method
    346 		 */
    347 		return API_ENODEV;
    348 
    349 	else if (di->type & DEV_TYP_NET)
    350 		err = dev_write_net(di->cookie, buf, *len);
    351 	else
    352 		err = API_ENODEV;
    353 
    354 	return err;
    355 }
    356 
    357 
    358 /*
    359  * pseudo signature:
    360  *
    361  * int API_dev_read(
    362  *	struct device_info *di,
    363  *	void *buf,
    364  *	size_t *len,
    365  *	unsigned long *start
    366  *	size_t *act_len
    367  * )
    368  *
    369  * buf:	ptr to buffer where to put the read data
    370  *
    371  * len: ptr to length to be read
    372  *      - network: len of packet to read (in bytes)
    373  *      - storage: # of blocks to read (can vary in size depending on define)
    374  *
    375  * start: ptr to start block (only used for storage devices, ignored for
    376  *        network)
    377  *
    378  * act_len: ptr to where to put the len actually read
    379  */
    380 static int API_dev_read(va_list ap)
    381 {
    382 	struct device_info *di;
    383 	void *buf;
    384 	lbasize_t *len_stor, *act_len_stor;
    385 	lbastart_t *start;
    386 	int *len_net, *act_len_net;
    387 
    388 	/* 1. arg is ptr to the device_info struct */
    389 	di = (struct device_info *)va_arg(ap, uintptr_t);
    390 	if (di == NULL)
    391 		return API_EINVAL;
    392 
    393 	/* XXX should we check if device is open? i.e. the ->state ? */
    394 
    395 	if (di->cookie == NULL)
    396 		return API_ENODEV;
    397 
    398 	/* 2. arg is ptr to buffer from where to put the read data */
    399 	buf = (void *)va_arg(ap, uintptr_t);
    400 	if (buf == NULL)
    401 		return API_EINVAL;
    402 
    403 	if (di->type & DEV_TYP_STOR) {
    404 		/* 3. arg - ptr to var with # of blocks to read */
    405 		len_stor = (lbasize_t *)va_arg(ap, uintptr_t);
    406 		if (!len_stor)
    407 			return API_EINVAL;
    408 		if (*len_stor <= 0)
    409 			return API_EINVAL;
    410 
    411 		/* 4. arg - ptr to var with start block */
    412 		start = (lbastart_t *)va_arg(ap, uintptr_t);
    413 
    414 		/* 5. arg - ptr to var where to put the len actually read */
    415 		act_len_stor = (lbasize_t *)va_arg(ap, uintptr_t);
    416 		if (!act_len_stor)
    417 			return API_EINVAL;
    418 
    419 		*act_len_stor = dev_read_stor(di->cookie, buf, *len_stor, *start);
    420 
    421 	} else if (di->type & DEV_TYP_NET) {
    422 
    423 		/* 3. arg points to the var with length of packet to read */
    424 		len_net = (int *)va_arg(ap, uintptr_t);
    425 		if (!len_net)
    426 			return API_EINVAL;
    427 		if (*len_net <= 0)
    428 			return API_EINVAL;
    429 
    430 		/* 4. - ptr to var where to put the len actually read */
    431 		act_len_net = (int *)va_arg(ap, uintptr_t);
    432 		if (!act_len_net)
    433 			return API_EINVAL;
    434 
    435 		*act_len_net = dev_read_net(di->cookie, buf, *len_net);
    436 
    437 	} else
    438 		return API_ENODEV;
    439 
    440 	return 0;
    441 }
    442 
    443 
    444 /*
    445  * pseudo signature:
    446  *
    447  * int API_env_get(const char *name, char **value)
    448  *
    449  * name: ptr to name of env var
    450  */
    451 static int API_env_get(va_list ap)
    452 {
    453 	char *name, **value;
    454 
    455 	if ((name = (char *)va_arg(ap, uintptr_t)) == NULL)
    456 		return API_EINVAL;
    457 	if ((value = (char **)va_arg(ap, uintptr_t)) == NULL)
    458 		return API_EINVAL;
    459 
    460 	*value = env_get(name);
    461 
    462 	return 0;
    463 }
    464 
    465 /*
    466  * pseudo signature:
    467  *
    468  * int API_env_set(const char *name, const char *value)
    469  *
    470  * name: ptr to name of env var
    471  *
    472  * value: ptr to value to be set
    473  */
    474 static int API_env_set(va_list ap)
    475 {
    476 	char *name, *value;
    477 
    478 	if ((name = (char *)va_arg(ap, uintptr_t)) == NULL)
    479 		return API_EINVAL;
    480 	if ((value = (char *)va_arg(ap, uintptr_t)) == NULL)
    481 		return API_EINVAL;
    482 
    483 	env_set(name, value);
    484 
    485 	return 0;
    486 }
    487 
    488 /*
    489  * pseudo signature:
    490  *
    491  * int API_env_enum(const char *last, char **next)
    492  *
    493  * last: ptr to name of env var found in last iteration
    494  */
    495 static int API_env_enum(va_list ap)
    496 {
    497 	int i, buflen;
    498 	char *last, **next, *s;
    499 	ENTRY *match, search;
    500 	static char *var;
    501 
    502 	last = (char *)va_arg(ap, unsigned long);
    503 
    504 	if ((next = (char **)va_arg(ap, uintptr_t)) == NULL)
    505 		return API_EINVAL;
    506 
    507 	if (last == NULL) {
    508 		var = NULL;
    509 		i = 0;
    510 	} else {
    511 		var = strdup(last);
    512 		s = strchr(var, '=');
    513 		if (s != NULL)
    514 			*s = 0;
    515 		search.key = var;
    516 		i = hsearch_r(search, FIND, &match, &env_htab, 0);
    517 		if (i == 0) {
    518 			i = API_EINVAL;
    519 			goto done;
    520 		}
    521 	}
    522 
    523 	/* match the next entry after i */
    524 	i = hmatch_r("", i, &match, &env_htab);
    525 	if (i == 0)
    526 		goto done;
    527 	buflen = strlen(match->key) + strlen(match->data) + 2;
    528 	var = realloc(var, buflen);
    529 	snprintf(var, buflen, "%s=%s", match->key, match->data);
    530 	*next = var;
    531 	return 0;
    532 
    533 done:
    534 	free(var);
    535 	var = NULL;
    536 	*next = NULL;
    537 	return i;
    538 }
    539 
    540 /*
    541  * pseudo signature:
    542  *
    543  * int API_display_get_info(int type, struct display_info *di)
    544  */
    545 static int API_display_get_info(va_list ap)
    546 {
    547 	int type;
    548 	struct display_info *di;
    549 
    550 	type = va_arg(ap, int);
    551 	di = va_arg(ap, struct display_info *);
    552 
    553 	return display_get_info(type, di);
    554 }
    555 
    556 /*
    557  * pseudo signature:
    558  *
    559  * int API_display_draw_bitmap(ulong bitmap, int x, int y)
    560  */
    561 static int API_display_draw_bitmap(va_list ap)
    562 {
    563 	ulong bitmap;
    564 	int x, y;
    565 
    566 	bitmap = va_arg(ap, ulong);
    567 	x = va_arg(ap, int);
    568 	y = va_arg(ap, int);
    569 
    570 	return display_draw_bitmap(bitmap, x, y);
    571 }
    572 
    573 /*
    574  * pseudo signature:
    575  *
    576  * void API_display_clear(void)
    577  */
    578 static int API_display_clear(va_list ap)
    579 {
    580 	display_clear();
    581 	return 0;
    582 }
    583 
    584 static cfp_t calls_table[API_MAXCALL] = { NULL, };
    585 
    586 /*
    587  * The main syscall entry point - this is not reentrant, only one call is
    588  * serviced until finished.
    589  *
    590  * e.g. syscall(1, int *, u_int32_t, u_int32_t, u_int32_t, u_int32_t);
    591  *
    592  * call:	syscall number
    593  *
    594  * retval:	points to the return value placeholder, this is the place the
    595  *		syscall puts its return value, if NULL the caller does not
    596  *		expect a return value
    597  *
    598  * ...		syscall arguments (variable number)
    599  *
    600  * returns:	0 if the call not found, 1 if serviced
    601  */
    602 int syscall(int call, int *retval, ...)
    603 {
    604 	va_list	ap;
    605 	int rv;
    606 
    607 	if (call < 0 || call >= calls_no) {
    608 		debugf("invalid call #%d\n", call);
    609 		return 0;
    610 	}
    611 
    612 	if (calls_table[call] == NULL) {
    613 		debugf("syscall #%d does not have a handler\n", call);
    614 		return 0;
    615 	}
    616 
    617 	va_start(ap, retval);
    618 	rv = calls_table[call](ap);
    619 	if (retval != NULL)
    620 		*retval = rv;
    621 
    622 	return 1;
    623 }
    624 
    625 void api_init(void)
    626 {
    627 	struct api_signature *sig;
    628 
    629 	/* TODO put this into linker set one day... */
    630 	calls_table[API_RSVD] = NULL;
    631 	calls_table[API_GETC] = &API_getc;
    632 	calls_table[API_PUTC] = &API_putc;
    633 	calls_table[API_TSTC] = &API_tstc;
    634 	calls_table[API_PUTS] = &API_puts;
    635 	calls_table[API_RESET] = &API_reset;
    636 	calls_table[API_GET_SYS_INFO] = &API_get_sys_info;
    637 	calls_table[API_UDELAY] = &API_udelay;
    638 	calls_table[API_GET_TIMER] = &API_get_timer;
    639 	calls_table[API_DEV_ENUM] = &API_dev_enum;
    640 	calls_table[API_DEV_OPEN] = &API_dev_open;
    641 	calls_table[API_DEV_CLOSE] = &API_dev_close;
    642 	calls_table[API_DEV_READ] = &API_dev_read;
    643 	calls_table[API_DEV_WRITE] = &API_dev_write;
    644 	calls_table[API_ENV_GET] = &API_env_get;
    645 	calls_table[API_ENV_SET] = &API_env_set;
    646 	calls_table[API_ENV_ENUM] = &API_env_enum;
    647 	calls_table[API_DISPLAY_GET_INFO] = &API_display_get_info;
    648 	calls_table[API_DISPLAY_DRAW_BITMAP] = &API_display_draw_bitmap;
    649 	calls_table[API_DISPLAY_CLEAR] = &API_display_clear;
    650 	calls_no = API_MAXCALL;
    651 
    652 	debugf("API initialized with %d calls\n", calls_no);
    653 
    654 	dev_stor_init();
    655 
    656 	/*
    657 	 * Produce the signature so the API consumers can find it
    658 	 */
    659 	sig = malloc(sizeof(struct api_signature));
    660 	if (sig == NULL) {
    661 		printf("API: could not allocate memory for the signature!\n");
    662 		return;
    663 	}
    664 
    665 	env_set_hex("api_address", (unsigned long)sig);
    666 	debugf("API sig @ 0x%lX\n", (unsigned long)sig);
    667 	memcpy(sig->magic, API_SIG_MAGIC, 8);
    668 	sig->version = API_SIG_VERSION;
    669 	sig->syscall = &syscall;
    670 	sig->checksum = 0;
    671 	sig->checksum = crc32(0, (unsigned char *)sig,
    672 			      sizeof(struct api_signature));
    673 	debugf("syscall entry: 0x%lX\n", (unsigned long)sig->syscall);
    674 }
    675 
    676 void platform_set_mr(struct sys_info *si, unsigned long start, unsigned long size,
    677 			int flags)
    678 {
    679 	int i;
    680 
    681 	if (!si->mr || !size || (flags == 0))
    682 		return;
    683 
    684 	/* find free slot */
    685 	for (i = 0; i < si->mr_no; i++)
    686 		if (si->mr[i].flags == 0) {
    687 			/* insert new mem region */
    688 			si->mr[i].start = start;
    689 			si->mr[i].size = size;
    690 			si->mr[i].flags = flags;
    691 			return;
    692 		}
    693 }
    694