1 /*
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright © 2019 Keith Packard
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above
14 * copyright notice, this list of conditions and the following
15 * disclaimer in the documentation and/or other materials provided
16 * with the distribution.
17 *
18 * 3. Neither the name of the copyright holder nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
27 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
28 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
29 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
31 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
33 * OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 #include <picotls.h>
37 #include <string.h>
38 #include <stdint.h>
39
40 /*
41 * The TLS block consists of initialized data immediately followed by
42 * zero filled data
43 *
44 * These addresses must be defined by the loader configuration file
45 */
46
47 extern char __tdata_source[]; /* Source of TLS initialization data (in ROM) */
48
49 extern char __tdata_start[]; /* Start of static tdata area */
50 extern char __tdata_end[]; /* End of static tdata area */
51 extern char __tbss_start[]; /* Start of static zero-initialized TLS data */
52 extern char __tbss_end[]; /* End of static zero-initialized TLS data */
53
54 #ifdef __PICOLIBC_CRT_RUNTIME_SIZE
55 #define __tdata_size (__tdata_end - __tdata_start)
56 #define __tbss_size (__tbss_end - __tbss_start)
57 #define __tbss_offset (__tbss_start - __tdata_start)
58 #else
59 extern char __tdata_size[]; /* Size of TLS initized data */
60 extern char __tbss_size[]; /* Size of TLS zero-filled data */
61 extern char __tbss_offset[]; /* Offset from tdata to tbss */
62 #endif
63
64 void
_init_tls(void * __tls)65 _init_tls(void *__tls)
66 {
67 char *tls = __tls;
68
69 /* Copy tls initialized data */
70 memcpy(tls, __tdata_source, (uintptr_t) __tdata_size);
71
72 /* Clear tls zero data */
73 memset(tls + (uintptr_t) __tbss_offset, '\0', (uintptr_t) __tbss_size);
74 }
75
