1 #include <common.h> 2 #include <exports.h> 3 4 #ifndef GCC_VERSION 5 #define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__) 6 #endif /* GCC_VERSION */ 7 8 #if defined(CONFIG_X86) 9 /* 10 * x86 does not have a dedicated register to store the pointer to 11 * the global_data. Thus the jump table address is stored in a 12 * global variable, but such approach does not allow for execution 13 * from flash memory. The global_data address is passed as argv[-1] 14 * to the application program. 15 */ 16 static void **jt; 17 gd_t *global_data; 18 19 #define EXPORT_FUNC(x) \ 20 asm volatile ( \ 21 " .globl " #x "\n" \ 22 #x ":\n" \ 23 " movl %0, %%eax\n" \ 24 " movl jt, %%ecx\n" \ 25 " jmp *(%%ecx, %%eax)\n" \ 26 : : "i"(XF_ ## x * sizeof(void *)) : "eax", "ecx"); 27 #elif defined(CONFIG_PPC) 28 /* 29 * r2 holds the pointer to the global_data, r11 is a call-clobbered 30 * register 31 */ 32 #define EXPORT_FUNC(x) \ 33 asm volatile ( \ 34 " .globl " #x "\n" \ 35 #x ":\n" \ 36 " lwz %%r11, %0(%%r2)\n" \ 37 " lwz %%r11, %1(%%r11)\n" \ 38 " mtctr %%r11\n" \ 39 " bctr\n" \ 40 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r11"); 41 #elif defined(CONFIG_ARM) 42 /* 43 * r8 holds the pointer to the global_data, ip is a call-clobbered 44 * register 45 */ 46 #define EXPORT_FUNC(x) \ 47 asm volatile ( \ 48 " .globl " #x "\n" \ 49 #x ":\n" \ 50 " ldr ip, [r8, %0]\n" \ 51 " ldr pc, [ip, %1]\n" \ 52 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "ip"); 53 #elif defined(CONFIG_MIPS) 54 /* 55 * k0 ($26) holds the pointer to the global_data; t9 ($25) is a call- 56 * clobbered register that is also used to set gp ($26). Note that the 57 * jr instruction also executes the instruction immediately following 58 * it; however, GCC/mips generates an additional `nop' after each asm 59 * statement 60 */ 61 #define EXPORT_FUNC(x) \ 62 asm volatile ( \ 63 " .globl " #x "\n" \ 64 #x ":\n" \ 65 " lw $25, %0($26)\n" \ 66 " lw $25, %1($25)\n" \ 67 " jr $25\n" \ 68 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "t9"); 69 #elif defined(CONFIG_NIOS2) 70 /* 71 * gp holds the pointer to the global_data, r8 is call-clobbered 72 */ 73 #define EXPORT_FUNC(x) \ 74 asm volatile ( \ 75 " .globl " #x "\n" \ 76 #x ":\n" \ 77 " movhi r8, %%hi(%0)\n" \ 78 " ori r8, r0, %%lo(%0)\n" \ 79 " add r8, r8, gp\n" \ 80 " ldw r8, 0(r8)\n" \ 81 " ldw r8, %1(r8)\n" \ 82 " jmp r8\n" \ 83 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "gp"); 84 #elif defined(CONFIG_M68K) 85 /* 86 * d7 holds the pointer to the global_data, a0 is a call-clobbered 87 * register 88 */ 89 #define EXPORT_FUNC(x) \ 90 asm volatile ( \ 91 " .globl " #x "\n" \ 92 #x ":\n" \ 93 " move.l %%d7, %%a0\n" \ 94 " adda.l %0, %%a0\n" \ 95 " move.l (%%a0), %%a0\n" \ 96 " adda.l %1, %%a0\n" \ 97 " move.l (%%a0), %%a0\n" \ 98 " jmp (%%a0)\n" \ 99 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "a0"); 100 #elif defined(CONFIG_MICROBLAZE) 101 /* 102 * r31 holds the pointer to the global_data. r5 is a call-clobbered. 103 */ 104 #define EXPORT_FUNC(x) \ 105 asm volatile ( \ 106 " .globl " #x "\n" \ 107 #x ":\n" \ 108 " lwi r5, r31, %0\n" \ 109 " lwi r5, r5, %1\n" \ 110 " bra r5\n" \ 111 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r5"); 112 #elif defined(CONFIG_BLACKFIN) 113 /* 114 * P3 holds the pointer to the global_data, P0 is a call-clobbered 115 * register 116 */ 117 #define EXPORT_FUNC(x) \ 118 asm volatile ( \ 119 " .globl _" #x "\n_" \ 120 #x ":\n" \ 121 " P0 = [P3 + %0]\n" \ 122 " P0 = [P0 + %1]\n" \ 123 " JUMP (P0)\n" \ 124 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "P0"); 125 #elif defined(CONFIG_AVR32) 126 /* 127 * r6 holds the pointer to the global_data. r8 is call clobbered. 128 */ 129 #define EXPORT_FUNC(x) \ 130 asm volatile( \ 131 " .globl\t" #x "\n" \ 132 #x ":\n" \ 133 " ld.w r8, r6[%0]\n" \ 134 " ld.w pc, r8[%1]\n" \ 135 : \ 136 : "i"(offsetof(gd_t, jt)), "i"(XF_ ##x) \ 137 : "r8"); 138 #elif defined(CONFIG_SH) 139 /* 140 * r13 holds the pointer to the global_data. r1 is a call clobbered. 141 */ 142 #define EXPORT_FUNC(x) \ 143 asm volatile ( \ 144 " .align 2\n" \ 145 " .globl " #x "\n" \ 146 #x ":\n" \ 147 " mov r13, r1\n" \ 148 " add %0, r1\n" \ 149 " mov.l @r1, r2\n" \ 150 " add %1, r2\n" \ 151 " mov.l @r2, r1\n" \ 152 " jmp @r1\n" \ 153 " nop\n" \ 154 " nop\n" \ 155 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r1", "r2"); 156 #elif defined(CONFIG_SPARC) 157 /* 158 * g7 holds the pointer to the global_data. g1 is call clobbered. 159 */ 160 #define EXPORT_FUNC(x) \ 161 asm volatile( \ 162 " .globl\t" #x "\n" \ 163 #x ":\n" \ 164 " set %0, %%g1\n" \ 165 " or %%g1, %%g7, %%g1\n" \ 166 " ld [%%g1], %%g1\n" \ 167 " ld [%%g1 + %1], %%g1\n" \ 168 " jmp %%g1\n" \ 169 " nop\n" \ 170 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "g1" ); 171 #elif defined(CONFIG_NDS32) 172 /* 173 * r16 holds the pointer to the global_data. gp is call clobbered. 174 * not support reduced register (16 GPR). 175 */ 176 #define EXPORT_FUNC(x) \ 177 asm volatile ( \ 178 " .globl " #x "\n" \ 179 #x ":\n" \ 180 " lwi $r16, [$gp + (%0)]\n" \ 181 " lwi $r16, [$r16 + (%1)]\n" \ 182 " jr $r16\n" \ 183 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "$r16"); 184 #elif defined(CONFIG_OPENRISC) 185 /* 186 * r10 holds the pointer to the global_data, r13 is a call-clobbered 187 * register 188 */ 189 #define EXPORT_FUNC(x) \ 190 asm volatile ( \ 191 " .globl " #x "\n" \ 192 #x ":\n" \ 193 " l.lwz r13, %0(r10)\n" \ 194 " l.lwz r13, %1(r13)\n" \ 195 " l.jr r13\n" \ 196 " l.nop\n" \ 197 : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r13"); 198 #else 199 /*" addi $sp, $sp, -24\n" \ 200 " br $r16\n" \*/ 201 202 #error stubs definition missing for this architecture 203 #endif 204 205 /* This function is necessary to prevent the compiler from 206 * generating prologue/epilogue, preparing stack frame etc. 207 * The stub functions are special, they do not use the stack 208 * frame passed to them, but pass it intact to the actual 209 * implementation. On the other hand, asm() statements with 210 * arguments can be used only inside the functions (gcc limitation) 211 */ 212 #if GCC_VERSION < 3004 213 static 214 #endif /* GCC_VERSION */ 215 void __attribute__((unused)) dummy(void) 216 { 217 #include <_exports.h> 218 } 219 220 #include <asm/sections.h> 221 222 void app_startup(char * const *argv) 223 { 224 char *cp = __bss_start; 225 226 /* Zero out BSS */ 227 while (cp < _end) 228 *cp++ = 0; 229 230 #if defined(CONFIG_X86) 231 /* x86 does not have a dedicated register for passing global_data */ 232 global_data = (gd_t *)argv[-1]; 233 jt = global_data->jt; 234 #endif 235 } 236 237 #undef EXPORT_FUNC 238