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wdenk27b207f2003-07-24 23:38:38 +00001#include <exports.h>
2
wdenk93f6a672004-07-01 20:28:03 +00003#ifndef GCC_VERSION
4#define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__)
5#endif /* GCC_VERSION */
6
Graeme Russfea25722011-04-13 19:43:28 +10007#if defined(CONFIG_X86)
wdenk27b207f2003-07-24 23:38:38 +00008/*
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 */
15static void **jt;
wdenk77846742003-07-26 08:08:08 +000016gd_t *global_data;
wdenk27b207f2003-07-24 23:38:38 +000017
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/*
Wolfgang Denke7670f62008-02-14 22:43:22 +010028 * r2 holds the pointer to the global_data, r11 is a call-clobbered
wdenk27b207f2003-07-24 23:38:38 +000029 * register
30 */
31#define EXPORT_FUNC(x) \
32 asm volatile ( \
33" .globl " #x "\n" \
34#x ":\n" \
Wolfgang Denke7670f62008-02-14 22:43:22 +010035" lwz %%r11, %0(%%r2)\n" \
wdenk27b207f2003-07-24 23:38:38 +000036" 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");
wdenk5c952cf2004-10-10 21:27:30 +000068#elif defined(CONFIG_NIOS2)
69/*
Thomas Chou0df01fd2010-05-21 11:08:03 +080070 * gp holds the pointer to the global_data, r8 is call-clobbered
wdenk5c952cf2004-10-10 21:27:30 +000071 */
72#define EXPORT_FUNC(x) \
73 asm volatile ( \
74" .globl " #x "\n" \
75#x ":\n" \
76" movhi r8, %%hi(%0)\n" \
77" ori r8, r0, %%lo(%0)\n" \
Thomas Chou0df01fd2010-05-21 11:08:03 +080078" add r8, r8, gp\n" \
wdenk5c952cf2004-10-10 21:27:30 +000079" ldw r8, 0(r8)\n" \
80" ldw r8, %1(r8)\n" \
81" jmp r8\n" \
Thomas Chou0df01fd2010-05-21 11:08:03 +080082 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "gp");
wdenkbf9e3b32004-02-12 00:47:09 +000083#elif defined(CONFIG_M68K)
84/*
85 * d7 holds the pointer to the global_data, a0 is a call-clobbered
86 * register
87 */
88#define EXPORT_FUNC(x) \
89 asm volatile ( \
90" .globl " #x "\n" \
91#x ":\n" \
92" move.l %%d7, %%a0\n" \
93" adda.l %0, %%a0\n" \
94" move.l (%%a0), %%a0\n" \
95" adda.l %1, %%a0\n" \
96" move.l (%%a0), %%a0\n" \
97" jmp (%%a0)\n" \
98 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "a0");
wdenk857cad32004-07-10 23:48:41 +000099#elif defined(CONFIG_MICROBLAZE)
wdenk507bbe32004-04-18 21:13:41 +0000100/*
101 * r31 holds the pointer to the global_data. r5 is a call-clobbered.
102 */
103#define EXPORT_FUNC(x) \
104 asm volatile ( \
105" .globl " #x "\n" \
106#x ":\n" \
107" lwi r5, r31, %0\n" \
108" lwi r5, r5, %1\n" \
109" bra r5\n" \
110 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r5");
Wolfgang Denk0afe5192006-03-12 02:10:00 +0100111#elif defined(CONFIG_BLACKFIN)
112/*
Robin Getzc4db3352009-08-17 15:23:02 +0000113 * P3 holds the pointer to the global_data, P0 is a call-clobbered
Wolfgang Denk0afe5192006-03-12 02:10:00 +0100114 * register
115 */
116#define EXPORT_FUNC(x) \
Wolfgang Denk8e7b7032006-03-12 02:55:22 +0100117 asm volatile ( \
Wolfgang Denk61fb15c52007-12-27 01:52:50 +0100118" .globl _" #x "\n_" \
Wolfgang Denk0afe5192006-03-12 02:10:00 +0100119#x ":\n" \
Robin Getzc4db3352009-08-17 15:23:02 +0000120" P0 = [P3 + %0]\n" \
Wolfgang Denk0afe5192006-03-12 02:10:00 +0100121" P0 = [P0 + %1]\n" \
122" JUMP (P0)\n" \
123 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "P0");
Wolfgang Denk7b64fef2006-10-24 14:21:16 +0200124#elif defined(CONFIG_AVR32)
125/*
126 * r6 holds the pointer to the global_data. r8 is call clobbered.
127 */
128#define EXPORT_FUNC(x) \
129 asm volatile( \
130 " .globl\t" #x "\n" \
131 #x ":\n" \
132 " ld.w r8, r6[%0]\n" \
133 " ld.w pc, r8[%1]\n" \
134 : \
135 : "i"(offsetof(gd_t, jt)), "i"(XF_ ##x) \
136 : "r8");
Nobuhiro Iwamatsu0b135cf2007-05-13 20:58:00 +0900137#elif defined(CONFIG_SH)
138/*
139 * r13 holds the pointer to the global_data. r1 is a call clobbered.
140 */
Wolfgang Denk61fb15c52007-12-27 01:52:50 +0100141#define EXPORT_FUNC(x) \
142 asm volatile ( \
143 " .align 2\n" \
144 " .globl " #x "\n" \
145 #x ":\n" \
146 " mov r13, r1\n" \
147 " add %0, r1\n" \
Nobuhiro Iwamatsucae6f902008-10-09 13:54:33 +0900148 " mov.l @r1, r2\n" \
149 " add %1, r2\n" \
150 " mov.l @r2, r1\n" \
Wolfgang Denk61fb15c52007-12-27 01:52:50 +0100151 " jmp @r1\n" \
152 " nop\n" \
153 " nop\n" \
Nobuhiro Iwamatsucae6f902008-10-09 13:54:33 +0900154 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r1", "r2");
Daniel Hellstromc2f02da2008-03-28 09:47:00 +0100155#elif defined(CONFIG_SPARC)
156/*
157 * g7 holds the pointer to the global_data. g1 is call clobbered.
158 */
159#define EXPORT_FUNC(x) \
160 asm volatile( \
161" .globl\t" #x "\n" \
162#x ":\n" \
163" set %0, %%g1\n" \
164" or %%g1, %%g7, %%g1\n" \
165" ld [%%g1], %%g1\n" \
166" ld [%%g1 + %1], %%g1\n" \
Sergey Mironov2c0c58b2009-09-23 16:47:38 +0400167" jmp %%g1\n" \
Daniel Hellstromc2f02da2008-03-28 09:47:00 +0100168" nop\n" \
Sergey Mironov2c0c58b2009-09-23 16:47:38 +0400169 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "g1" );
Daniel Hellstromc2f02da2008-03-28 09:47:00 +0100170
wdenk27b207f2003-07-24 23:38:38 +0000171#else
172#error stubs definition missing for this architecture
173#endif
174
175/* This function is necessary to prevent the compiler from
176 * generating prologue/epilogue, preparing stack frame etc.
177 * The stub functions are special, they do not use the stack
178 * frame passed to them, but pass it intact to the actual
179 * implementation. On the other hand, asm() statements with
180 * arguments can be used only inside the functions (gcc limitation)
181 */
wdenk93f6a672004-07-01 20:28:03 +0000182#if GCC_VERSION < 3004
183static
184#endif /* GCC_VERSION */
185void __attribute__((unused)) dummy(void)
wdenk27b207f2003-07-24 23:38:38 +0000186{
187#include <_exports.h>
188}
189
Wolfgang Denk7ec830d2011-03-29 14:34:50 +0200190extern unsigned long __bss_start, _end;
wdenkd716b122004-04-12 16:12:49 +0000191
Wolfgang Denk54841ab2010-06-28 22:00:46 +0200192void app_startup(char * const *argv)
wdenk27b207f2003-07-24 23:38:38 +0000193{
Woodruff, Richard118978c2008-02-29 17:34:35 -0600194 unsigned char * cp = (unsigned char *) &__bss_start;
wdenkd716b122004-04-12 16:12:49 +0000195
196 /* Zero out BSS */
Wolfgang Denk7ec830d2011-03-29 14:34:50 +0200197 while (cp < (unsigned char *)&_end) {
wdenkd716b122004-04-12 16:12:49 +0000198 *cp++ = 0;
199 }
200
Graeme Russfea25722011-04-13 19:43:28 +1000201#if defined(CONFIG_X86)
wdenk27b207f2003-07-24 23:38:38 +0000202 /* x86 does not have a dedicated register for passing global_data */
wdenk77846742003-07-26 08:08:08 +0000203 global_data = (gd_t *)argv[-1];
204 jt = global_data->jt;
wdenk27b207f2003-07-24 23:38:38 +0000205#endif
206}
207
208#undef EXPORT_FUNC