1 /*
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright © 2019 Keith Packard
5 * Copyright © 2024 Stephen Street
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 *
14 * 2. Redistributions in binary form must reproduce the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer in the documentation and/or other materials provided
17 * with the distribution.
18 *
19 * 3. Neither the name of the copyright holder nor the names of its
20 * contributors may be used to endorse or promote products derived
21 * from this software without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
26 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
27 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
28 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
29 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
30 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
32 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
34 * OF THE POSSIBILITY OF SUCH DAMAGE.
35 */
36
37 #include <picotls.h>
38 #include <string.h>
39 #include <stdint.h>
40 #include "arm_tls.h"
41
42 /* This needs to be global so that __aeabi_read_tp can
43 * refer to it in an asm statement
44 */
45 #ifndef ARM_TLS_CP15
46 extern void *__tls[];
47 #endif
48
49 /* The size of the thread control block.
50 * TLS relocations are generated relative to
51 * a location this far *before* the first thread
52 * variable (!)
53 * NB: The actual size before tp also includes padding
54 * to align up to the alignment of .tdata/.tbss.
55 */
56 #define TCB_SIZE 8
57 extern char __arm32_tls_tcb_offset;
58 #define TP_OFFSET ((size_t)&__arm32_tls_tcb_offset)
59
60 void
_set_tls(void * tls)61 _set_tls(void *tls)
62 {
63 tls = (uint8_t *) tls - TP_OFFSET;
64 #ifdef ARM_TLS_CP15
65 __asm__("mcr p15, 0, %0, cr13, cr0, 3" : : "r" (tls));
66 #else
67 #ifdef ARM_RP2040
68 uint32_t cpuid = *(uint32_t *)0xd0000000;
69 __tls[cpuid] = tls;
70 #else
71 __tls[0] = tls;
72 #endif
73 #endif
74 }
75
