diff options
Diffstat (limited to 'target/linux/adm8668/image/lzma-loader/src/stubs.c')
| -rw-r--r-- | target/linux/adm8668/image/lzma-loader/src/stubs.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/target/linux/adm8668/image/lzma-loader/src/stubs.c b/target/linux/adm8668/image/lzma-loader/src/stubs.c new file mode 100644 index 000000000..468e5a1fd --- /dev/null +++ b/target/linux/adm8668/image/lzma-loader/src/stubs.c @@ -0,0 +1,52 @@ +#include <exports.h> + +#ifndef GCC_VERSION +#define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__) +#endif /* GCC_VERSION */ + +/* + * 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"); + +/* 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> +} + +#if 0 +extern unsigned long __bss_start, _end; + +void app_startup(char **argv) +{ + unsigned long * cp = &__bss_start; + + /* Zero out BSS */ + while (cp < &_end) { + *cp++ = 0; + } +} +#endif + +#undef EXPORT_FUNC |