diff options
Diffstat (limited to 'arch/powerpc/include/asm/code-patching.h')
| -rw-r--r-- | arch/powerpc/include/asm/code-patching.h | 51 |
1 files changed, 47 insertions, 4 deletions
diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h index 97e02f985df8..840a5509b3f1 100644 --- a/arch/powerpc/include/asm/code-patching.h +++ b/arch/powerpc/include/asm/code-patching.h @@ -42,18 +42,61 @@ void __patch_exception(int exc, unsigned long addr); } while (0) #endif +#define OP_RT_RA_MASK 0xffff0000UL +#define LIS_R2 0x3c020000UL +#define ADDIS_R2_R12 0x3c4c0000UL +#define ADDI_R2_R2 0x38420000UL + static inline unsigned long ppc_function_entry(void *func) { -#ifdef CONFIG_PPC64 +#if defined(CONFIG_PPC64) +#if defined(_CALL_ELF) && _CALL_ELF == 2 + u32 *insn = func; + + /* + * A PPC64 ABIv2 function may have a local and a global entry + * point. We need to use the local entry point when patching + * functions, so identify and step over the global entry point + * sequence. + * + * The global entry point sequence is always of the form: + * + * addis r2,r12,XXXX + * addi r2,r2,XXXX + * + * A linker optimisation may convert the addis to lis: + * + * lis r2,XXXX + * addi r2,r2,XXXX + */ + if ((((*insn & OP_RT_RA_MASK) == ADDIS_R2_R12) || + ((*insn & OP_RT_RA_MASK) == LIS_R2)) && + ((*(insn+1) & OP_RT_RA_MASK) == ADDI_R2_R2)) + return (unsigned long)(insn + 2); + else + return (unsigned long)func; +#else /* - * On PPC64 the function pointer actually points to the function's - * descriptor. The first entry in the descriptor is the address - * of the function text. + * On PPC64 ABIv1 the function pointer actually points to the + * function's descriptor. The first entry in the descriptor is the + * address of the function text. */ return ((func_descr_t *)func)->entry; +#endif #else return (unsigned long)func; #endif } +static inline unsigned long ppc_global_function_entry(void *func) +{ +#if defined(CONFIG_PPC64) && defined(_CALL_ELF) && _CALL_ELF == 2 + /* PPC64 ABIv2 the global entry point is at the address */ + return (unsigned long)func; +#else + /* All other cases there is no change vs ppc_function_entry() */ + return ppc_function_entry(func); +#endif +} + #endif /* _ASM_POWERPC_CODE_PATCHING_H */ |