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Diffstat (limited to 'include/lib/utils.h')
| -rw-r--r-- | include/lib/utils.h | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/include/lib/utils.h b/include/lib/utils.h index d46d8461d..f324a9909 100644 --- a/include/lib/utils.h +++ b/include/lib/utils.h @@ -67,6 +67,29 @@ void zero_normalmem(void *mem, u_register_t length); * zeroing. */ void zeromem(void *mem, u_register_t length); + +/* + * Utility function to return the address of a symbol. By default, the + * compiler generates adr/adrp instruction pair to return the reference + * to the symbol and this utility is used to override this compiler + * generated to code to use `ldr` instruction. + * + * This helps when Position Independent Executable needs to reference a symbol + * which is constant and does not depend on the execute address of the binary. + */ +#define DEFINE_LOAD_SYM_ADDR(_name) \ +static inline u_register_t load_addr_## _name(void) \ +{ \ + u_register_t v; \ + /* Create a void reference to silence compiler */ \ + (void) _name; \ + __asm__ volatile ("ldr %0, =" #_name : "=r" (v)); \ + return v; \ +} + +/* Helper to invoke the function defined by DEFINE_LOAD_SYM_ADDR() */ +#define LOAD_ADDR_OF(_name) (typeof(_name) *) load_addr_## _name() + #endif /* !(defined(__LINKER__) || defined(__ASSEMBLY__)) */ #endif /* __UTILS_H__ */ |