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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 | #include <exports.h> #ifndef GCC_VERSION #define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__) #endif /* GCC_VERSION */ #if defined(CONFIG_I386) /* * x86 does not have a dedicated register to store the pointer to * the global_data. Thus the jump table address is stored in a * global variable, but such approach does not allow for execution * from flash memory. The global_data address is passed as argv[-1] * to the application program. */ static void **jt; gd_t *global_data; #define EXPORT_FUNC(x) \ asm volatile ( \ " .globl " #x "\n" \ #x ":\n" \ " movl %0, %%eax\n" \ " movl jt, %%ecx\n" \ " jmp *(%%ecx, %%eax)\n" \ : : "i"(XF_ ## x * sizeof(void *)) : "eax", "ecx"); #elif defined(CONFIG_PPC) /* * r2 holds the pointer to the global_data, r11 is a call-clobbered * register */ #define EXPORT_FUNC(x) \ asm volatile ( \ " .globl " #x "\n" \ #x ":\n" \ " lwz %%r11, %0(%%r2)\n" \ " lwz %%r11, %1(%%r11)\n" \ " mtctr %%r11\n" \ " bctr\n" \ : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r11"); #elif defined(CONFIG_ARM) /* * r8 holds the pointer to the global_data, ip is a call-clobbered * register */ #define EXPORT_FUNC(x) \ asm volatile ( \ " .globl " #x "\n" \ #x ":\n" \ " ldr ip, [r8, %0]\n" \ " ldr pc, [ip, %1]\n" \ : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "ip"); #elif defined(CONFIG_MIPS) /* * k0 ($26) holds the pointer to the global_data; t9 ($25) is a call- * clobbered register that is also used to set gp ($26). Note that the * jr instruction also executes the instruction immediately following * it; however, GCC/mips generates an additional `nop' after each asm * statement */ #define EXPORT_FUNC(x) \ asm volatile ( \ " .globl " #x "\n" \ #x ":\n" \ " lw $25, %0($26)\n" \ " lw $25, %1($25)\n" \ " jr $25\n" \ : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "t9"); #elif defined(CONFIG_NIOS) /* * %g7 holds the pointer to the global_data. %g0 is call clobbered. */ #define EXPORT_FUNC(x) \ asm volatile ( \ " .globl " #x "\n" \ #x ":\n" \ " pfx %%hi(%0)\n" \ " movi %%g0, %%lo(%0)\n" \ " add %%g0, %%g7\n" \ " ld %%g0, [%%g0]\n" \ " pfx %1\n" \ " ld %%g0, [%%g0]\n" \ " jmp %%g0\n" \ " nop \n" \ : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x) : "r0"); #elif defined(CONFIG_NIOS2) /* * r15 holds the pointer to the global_data, r8 is call-clobbered */ #define EXPORT_FUNC(x) \ asm volatile ( \ " .globl " #x "\n" \ #x ":\n" \ " movhi r8, %%hi(%0)\n" \ " ori r8, r0, %%lo(%0)\n" \ " add r8, r8, r15\n" \ " ldw r8, 0(r8)\n" \ " ldw r8, %1(r8)\n" \ " jmp r8\n" \ : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r15"); #elif defined(CONFIG_M68K) /* * d7 holds the pointer to the global_data, a0 is a call-clobbered * register */ #define EXPORT_FUNC(x) \ asm volatile ( \ " .globl " #x "\n" \ #x ":\n" \ " move.l %%d7, %%a0\n" \ " adda.l %0, %%a0\n" \ " move.l (%%a0), %%a0\n" \ " adda.l %1, %%a0\n" \ " move.l (%%a0), %%a0\n" \ " jmp (%%a0)\n" \ : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "a0"); #elif defined(CONFIG_MICROBLAZE) /* * r31 holds the pointer to the global_data. r5 is a call-clobbered. */ #define EXPORT_FUNC(x) \ asm volatile ( \ " .globl " #x "\n" \ #x ":\n" \ " lwi r5, r31, %0\n" \ " lwi r5, r5, %1\n" \ " bra r5\n" \ : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r5"); #elif defined(CONFIG_BLACKFIN) /* * P5 holds the pointer to the global_data, P0 is a call-clobbered * register */ #define EXPORT_FUNC(x) \ asm volatile ( \ " .globl _" #x "\n_" \ #x ":\n" \ " P0 = [P5 + %0]\n" \ " P0 = [P0 + %1]\n" \ " JUMP (P0)\n" \ : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "P0"); #elif defined(CONFIG_AVR32) /* * r6 holds the pointer to the global_data. r8 is call clobbered. */ #define EXPORT_FUNC(x) \ asm volatile( \ " .globl\t" #x "\n" \ #x ":\n" \ " ld.w r8, r6[%0]\n" \ " ld.w pc, r8[%1]\n" \ : \ : "i"(offsetof(gd_t, jt)), "i"(XF_ ##x) \ : "r8"); #elif defined(CONFIG_SH) /* * r13 holds the pointer to the global_data. r1 is a call clobbered. */ #define EXPORT_FUNC(x) \ asm volatile ( \ " .align 2\n" \ " .globl " #x "\n" \ #x ":\n" \ " mov r13, r1\n" \ " add %0, r1\n" \ " add %1, r1\n" \ " jmp @r1\n" \ " nop\n" \ " nop\n" \ : : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "r1"); #else #error stubs definition missing for this architecture #endif /* This function is necessary to prevent the compiler from * generating prologue/epilogue, preparing stack frame etc. * The stub functions are special, they do not use the stack * frame passed to them, but pass it intact to the actual * implementation. On the other hand, asm() statements with * arguments can be used only inside the functions (gcc limitation) */ #if GCC_VERSION < 3004 static #endif /* GCC_VERSION */ void __attribute__((unused)) dummy(void) { #include <_exports.h> } extern unsigned long __bss_start, _end; void app_startup(char **argv) { unsigned char * cp = (unsigned char *) &__bss_start; /* Zero out BSS */ while (cp < (unsigned char *)&_end) { *cp++ = 0; } #if defined(CONFIG_I386) /* x86 does not have a dedicated register for passing global_data */ global_data = (gd_t *)argv[-1]; jt = global_data->jt; #endif } #undef EXPORT_FUNC |