]> git.sur5r.net Git - u-boot/blob - examples/standalone/stubs.c
Fix bug in jumptable call stubs for SPARC.
[u-boot] / examples / standalone / stubs.c
1 #include <exports.h>
2
3 #ifndef GCC_VERSION
4 #define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__)
5 #endif /* GCC_VERSION */
6
7 #if defined(CONFIG_I386)
8 /*
9  * x86 does not have a dedicated register to store the pointer to
10  * the global_data. Thus the jump table address is stored in a
11  * global variable, but such approach does not allow for execution
12  * from flash memory. The global_data address is passed as argv[-1]
13  * to the application program.
14  */
15 static void **jt;
16 gd_t *global_data;
17
18 #define EXPORT_FUNC(x) \
19         asm volatile (                  \
20 "       .globl " #x "\n"                \
21 #x ":\n"                                \
22 "       movl    %0, %%eax\n"            \
23 "       movl    jt, %%ecx\n"            \
24 "       jmp     *(%%ecx, %%eax)\n"      \
25         : : "i"(XF_ ## x * sizeof(void *)) : "eax", "ecx");
26 #elif defined(CONFIG_PPC)
27 /*
28  * r2 holds the pointer to the global_data, r11 is a call-clobbered
29  * register
30  */
31 #define EXPORT_FUNC(x) \
32         asm volatile (                  \
33 "       .globl " #x "\n"                \
34 #x ":\n"                                \
35 "       lwz     %%r11, %0(%%r2)\n"      \
36 "       lwz     %%r11, %1(%%r11)\n"     \
37 "       mtctr   %%r11\n"                \
38 "       bctr\n"                         \
39         : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r11");
40 #elif defined(CONFIG_ARM)
41 /*
42  * r8 holds the pointer to the global_data, ip is a call-clobbered
43  * register
44  */
45 #define EXPORT_FUNC(x) \
46         asm volatile (                  \
47 "       .globl " #x "\n"                \
48 #x ":\n"                                \
49 "       ldr     ip, [r8, %0]\n"         \
50 "       ldr     pc, [ip, %1]\n"         \
51         : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "ip");
52 #elif defined(CONFIG_MIPS)
53 /*
54  * k0 ($26) holds the pointer to the global_data; t9 ($25) is a call-
55  * clobbered register that is also used to set gp ($26). Note that the
56  * jr instruction also executes the instruction immediately following
57  * it; however, GCC/mips generates an additional `nop' after each asm
58  * statement
59  */
60 #define EXPORT_FUNC(x) \
61         asm volatile (                  \
62 "       .globl " #x "\n"                \
63 #x ":\n"                                \
64 "       lw      $25, %0($26)\n"         \
65 "       lw      $25, %1($25)\n"         \
66 "       jr      $25\n"                  \
67         : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "t9");
68 #elif defined(CONFIG_NIOS)
69 /*
70  * %g7 holds the pointer to the global_data. %g0 is call clobbered.
71  */
72 #define EXPORT_FUNC(x) \
73         asm volatile (                  \
74 "       .globl " #x "\n"                \
75 #x ":\n"                                \
76 "       pfx     %%hi(%0)\n"             \
77 "       movi    %%g0, %%lo(%0)\n"       \
78 "       add     %%g0, %%g7\n"           \
79 "       ld      %%g0, [%%g0]\n"         \
80 "       pfx     %1\n"                   \
81 "       ld      %%g0, [%%g0]\n"         \
82 "       jmp     %%g0\n"                 \
83 "       nop     \n"                     \
84         : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x) : "r0");
85 #elif defined(CONFIG_NIOS2)
86 /*
87  * r15 holds the pointer to the global_data, r8 is call-clobbered
88  */
89 #define EXPORT_FUNC(x) \
90         asm volatile (                  \
91 "       .globl " #x "\n"                \
92 #x ":\n"                                \
93 "       movhi   r8, %%hi(%0)\n"         \
94 "       ori     r8, r0, %%lo(%0)\n"     \
95 "       add     r8, r8, r15\n"          \
96 "       ldw     r8, 0(r8)\n"            \
97 "       ldw     r8, %1(r8)\n"           \
98 "       jmp     r8\n"                   \
99         : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r15");
100 #elif defined(CONFIG_M68K)
101 /*
102  * d7 holds the pointer to the global_data, a0 is a call-clobbered
103  * register
104  */
105 #define EXPORT_FUNC(x) \
106         asm volatile (                  \
107 "       .globl " #x "\n"                \
108 #x ":\n"                                \
109 "       move.l  %%d7, %%a0\n"           \
110 "       adda.l  %0, %%a0\n"             \
111 "       move.l  (%%a0), %%a0\n"         \
112 "       adda.l  %1, %%a0\n"             \
113 "       move.l  (%%a0), %%a0\n"         \
114 "       jmp     (%%a0)\n"                       \
115         : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "a0");
116 #elif defined(CONFIG_MICROBLAZE)
117 /*
118  * r31 holds the pointer to the global_data. r5 is a call-clobbered.
119  */
120 #define EXPORT_FUNC(x)                          \
121         asm volatile (                          \
122 "       .globl " #x "\n"                        \
123 #x ":\n"                                        \
124 "       lwi     r5, r31, %0\n"                  \
125 "       lwi     r5, r5, %1\n"                   \
126 "       bra     r5\n"                           \
127         : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r5");
128 #elif defined(CONFIG_BLACKFIN)
129 /*
130  * P3 holds the pointer to the global_data, P0 is a call-clobbered
131  * register
132  */
133 #define EXPORT_FUNC(x)                  \
134         asm volatile (                  \
135 "       .globl _" #x "\n_"              \
136 #x ":\n"                                \
137 "       P0 = [P3 + %0]\n"               \
138 "       P0 = [P0 + %1]\n"               \
139 "       JUMP (P0)\n"                    \
140         : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "P0");
141 #elif defined(CONFIG_AVR32)
142 /*
143  * r6 holds the pointer to the global_data. r8 is call clobbered.
144  */
145 #define EXPORT_FUNC(x)                                  \
146         asm volatile(                                   \
147                 "       .globl\t" #x "\n"               \
148                 #x ":\n"                                \
149                 "       ld.w    r8, r6[%0]\n"           \
150                 "       ld.w    pc, r8[%1]\n"           \
151                 :                                       \
152                 : "i"(offsetof(gd_t, jt)), "i"(XF_ ##x) \
153                 : "r8");
154 #elif defined(CONFIG_SH)
155 /*
156  * r13 holds the pointer to the global_data. r1 is a call clobbered.
157  */
158 #define EXPORT_FUNC(x)                                  \
159         asm volatile (                                  \
160                 "       .align  2\n"                    \
161                 "       .globl " #x "\n"                \
162                 #x ":\n"                                \
163                 "       mov     r13, r1\n"              \
164                 "       add     %0, r1\n"               \
165                 "       mov.l @r1, r2\n"        \
166                 "       add     %1, r2\n"               \
167                 "       mov.l @r2, r1\n"        \
168                 "       jmp     @r1\n"                  \
169                 "       nop\n"                          \
170                 "       nop\n"                          \
171                 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r1", "r2");
172 #elif defined(CONFIG_SPARC)
173 /*
174  * g7 holds the pointer to the global_data. g1 is call clobbered.
175  */
176 #define EXPORT_FUNC(x)                                  \
177         asm volatile(                                   \
178 "       .globl\t" #x "\n"                               \
179 #x ":\n"                                                \
180 "       set %0, %%g1\n"                                 \
181 "       or %%g1, %%g7, %%g1\n"                          \
182 "       ld [%%g1], %%g1\n"                              \
183 "       ld [%%g1 + %1], %%g1\n"                         \
184 "       jmp %%g1\n"                                     \
185 "       nop\n"                                          \
186         : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "g1" );
187
188 #else
189 #error stubs definition missing for this architecture
190 #endif
191
192 /* This function is necessary to prevent the compiler from
193  * generating prologue/epilogue, preparing stack frame etc.
194  * The stub functions are special, they do not use the stack
195  * frame passed to them, but pass it intact to the actual
196  * implementation. On the other hand, asm() statements with
197  * arguments can be used only inside the functions (gcc limitation)
198  */
199 #if GCC_VERSION < 3004
200 static
201 #endif /* GCC_VERSION */
202 void __attribute__((unused)) dummy(void)
203 {
204 #include <_exports.h>
205 }
206
207 extern unsigned long __bss_start, _end;
208
209 void app_startup(char **argv)
210 {
211         unsigned char * cp = (unsigned char *) &__bss_start;
212
213         /* Zero out BSS */
214         while (cp < (unsigned char *)&_end) {
215                 *cp++ = 0;
216         }
217
218 #if defined(CONFIG_I386)
219         /* x86 does not have a dedicated register for passing global_data */
220         global_data = (gd_t *)argv[-1];
221         jt = global_data->jt;
222 #endif
223 }
224
225 #undef EXPORT_FUNC