xref: /aosp_15_r20/external/mesa3d/src/mapi/glapi/glapi_entrypoint.c (revision 6104692788411f58d303aa86923a9ff6ecaded22)
1 /*
2  * Mesa 3-D graphics library
3  *
4  * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included
14  * in all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  */
24 
25 /**
26  * \file glapi_entrypoint.c
27  *
28  * Arch-specific code for manipulating GL API entrypoints (dispatch stubs).
29  */
30 
31 
32 #include <string.h>
33 
34 #include "c11/threads.h"
35 #include "glapi/glapi_priv.h"
36 
37 
38 #ifdef USE_X86_ASM
39 
40 extern       GLubyte gl_dispatch_functions_start[];
41 extern       GLubyte gl_dispatch_functions_end[];
42 
43 #endif /* USE_X86_ASM */
44 
45 
46 #if defined(DISPATCH_FUNCTION_SIZE)
47 
48 _glapi_proc
get_entrypoint_address(unsigned int functionOffset)49 get_entrypoint_address(unsigned int functionOffset)
50 {
51    return (_glapi_proc) (gl_dispatch_functions_start
52                          + (DISPATCH_FUNCTION_SIZE * functionOffset));
53 }
54 
55 #endif
56 
57 
58 #if defined(USE_X86_ASM)
59 
60 /**
61  * Perform platform-specific GL API entry-point fixups.
62  */
63 static void
init_glapi_relocs(void)64 init_glapi_relocs( void )
65 {
66 #if !defined(GLX_X86_READONLY_TEXT)
67     extern unsigned long _x86_get_dispatch(void);
68     char run_time_patch[] = {
69        0x65, 0xa1, 0, 0, 0, 0 /* movl %gs:0,%eax */
70     };
71     GLuint *offset = (GLuint *) &run_time_patch[2]; /* 32-bits for x86/32 */
72     const GLubyte * const get_disp = (const GLubyte *) run_time_patch;
73     GLubyte * curr_func = (GLubyte *) gl_dispatch_functions_start;
74 
75     *offset = _x86_get_dispatch();
76     while ( curr_func != (GLubyte *) gl_dispatch_functions_end ) {
77 	(void) memcpy( curr_func, get_disp, sizeof(run_time_patch));
78 	curr_func += DISPATCH_FUNCTION_SIZE;
79     }
80 #endif
81 }
82 
83 #elif defined(USE_SPARC_ASM)
84 
85 extern void __glapi_sparc_icache_flush(unsigned int *);
86 
87 static void
init_glapi_relocs(void)88 init_glapi_relocs( void )
89 {
90     static const unsigned int template[] = {
91 	0x05000000, /* sethi %hi(_glapi_tls_Dispatch), %g2 */
92 	0x8730e00a, /* srl %g3, 10, %g3 */
93 	0x8410a000, /* or %g2, %lo(_glapi_tls_Dispatch), %g2 */
94 #ifdef __arch64__
95 	0xc259c002, /* ldx [%g7 + %g2], %g1 */
96 	0xc2584003, /* ldx [%g1 + %g3], %g1 */
97 #else
98 	0xc201c002, /* ld [%g7 + %g2], %g1 */
99 	0xc2004003, /* ld [%g1 + %g3], %g1 */
100 #endif
101 	0x81c04000, /* jmp %g1 */
102 	0x01000000, /* nop  */
103     };
104     extern unsigned int __glapi_sparc_tls_stub;
105     extern unsigned long __glapi_sparc_get_dispatch(void);
106     unsigned int *code = &__glapi_sparc_tls_stub;
107     unsigned long dispatch = __glapi_sparc_get_dispatch();
108 
109     code[0] = template[0] | (dispatch >> 10);
110     code[1] = template[1];
111     __glapi_sparc_icache_flush(&code[0]);
112     code[2] = template[2] | (dispatch & 0x3ff);
113     code[3] = template[3];
114     __glapi_sparc_icache_flush(&code[2]);
115     code[4] = template[4];
116     code[5] = template[5];
117     __glapi_sparc_icache_flush(&code[4]);
118     code[6] = template[6];
119     __glapi_sparc_icache_flush(&code[6]);
120 }
121 
122 
123 #else /* USE_*_ASM */
124 
125 static void
init_glapi_relocs(void)126 init_glapi_relocs( void )
127 {
128 }
129 
130 #endif /* USE_*_ASM */
131 
132 
133 void
init_glapi_relocs_once(void)134 init_glapi_relocs_once( void )
135 {
136    static once_flag flag = ONCE_FLAG_INIT;
137    call_once(&flag, init_glapi_relocs);
138 }
139