diff options
Diffstat (limited to 'include/asm-arm/elf.h')
-rw-r--r-- | include/asm-arm/elf.h | 48 |
1 files changed, 16 insertions, 32 deletions
diff --git a/include/asm-arm/elf.h b/include/asm-arm/elf.h index f3929307a56b..642382d2c9f0 100644 --- a/include/asm-arm/elf.h +++ b/include/asm-arm/elf.h @@ -114,40 +114,24 @@ extern char elf_platform[]; have no such handler. */ #define ELF_PLAT_INIT(_r, load_addr) (_r)->ARM_r0 = 0 -#ifndef CONFIG_IWMMXT - -/* Old NetWinder binaries were compiled in such a way that the iBCS - heuristic always trips on them. Until these binaries become uncommon - enough not to care, don't trust the `ibcs' flag here. In any case - there is no other ELF system currently supported by iBCS. - @@ Could print a warning message to encourage users to upgrade. */ -#define SET_PERSONALITY(ex,ibcs2) \ - set_personality(((ex).e_flags & EF_ARM_APCS26 ? PER_LINUX : PER_LINUX_32BIT)) - -#else - /* - * All iWMMXt capable CPUs don't support 26-bit mode. Yet they can run - * legacy binaries which used to contain FPA11 floating point instructions - * that have always been emulated by the kernel. PFA11 and iWMMXt overlap - * on coprocessor 1 space though. We therefore must decide if given task - * is allowed to use CP 0 and 1 for iWMMXt, or if they should be blocked - * at all times for the prefetch exception handler to catch FPA11 opcodes - * and emulate them. The best indication to discriminate those two cases - * is the SOFT_FLOAT flag in the ELF header. + * Since the FPA coprocessor uses CP1 and CP2, and iWMMXt uses CP0 + * and CP1, we only enable access to the iWMMXt coprocessor if the + * binary is EABI or softfloat (and thus, guaranteed not to use + * FPA instructions.) */ - -#define SET_PERSONALITY(ex,ibcs2) \ -do { \ - set_personality(PER_LINUX_32BIT); \ - if (((ex).e_flags & EF_ARM_EABI_MASK) || \ - ((ex).e_flags & EF_ARM_SOFT_FLOAT)) \ - set_thread_flag(TIF_USING_IWMMXT); \ - else \ - clear_thread_flag(TIF_USING_IWMMXT); \ -} while (0) - -#endif +#define SET_PERSONALITY(ex, ibcs2) \ + do { \ + if ((ex).e_flags & EF_ARM_APCS26) { \ + set_personality(PER_LINUX); \ + } else { \ + set_personality(PER_LINUX_32BIT); \ + if (elf_hwcap & HWCAP_IWMMXT && (ex).e_flags & (EF_ARM_EABI_MASK | EF_ARM_SOFT_FLOAT)) \ + set_thread_flag(TIF_USING_IWMMXT); \ + else \ + clear_thread_flag(TIF_USING_IWMMXT); \ + } \ + } while (0) #endif |