powerpc: Provide a suitable AT_PLATFORM value
The glibc folks want to use AT_PLATFORM to select between possible
alternative versions of shared libraries. This commit makes the kernel
supply an AT_PLATFORM string that indicates what class of processor
we are running on. Processors with the same set of user-level
instructions and roughly the same instruction scheduling characteristics
are given the same AT_PLATFORM value; for example, 821, 823 and 860
are all reported as "ppc823", and 7447, 7447A, 7448, 7450, 7451, 7455
are all called "ppc7450".
The intention is that the AT_PLATFORM values match the values that
gcc accepts for the -mcpu= option. For values which are numeric
(e.g. -mcpu=750), "ppc" has been prepended.
This also adds a PPC_FEATURE_BOOKE bit to the AT_HWCAP value and sets
it for the 440 family and the Freescale 85xx family.
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/include/asm-powerpc/elf.h b/include/asm-powerpc/elf.h
index 45f2af6..94d228f 100644
--- a/include/asm-powerpc/elf.h
+++ b/include/asm-powerpc/elf.h
@@ -221,21 +221,19 @@
instruction set this cpu supports. This could be done in userspace,
but it's not easy, and we've already done it here. */
# define ELF_HWCAP (cur_cpu_spec->cpu_user_features)
+
+/* This yields a string that ld.so will use to load implementation
+ specific libraries for optimization. This is more specific in
+ intent than poking at uname or /proc/cpuinfo. */
+
+#define ELF_PLATFORM (cur_cpu_spec->platform)
+
#ifdef __powerpc64__
# define ELF_PLAT_INIT(_r, load_addr) do { \
_r->gpr[2] = load_addr; \
} while (0)
#endif /* __powerpc64__ */
-/* This yields a string that ld.so will use to load implementation
- specific libraries for optimization. This is more specific in
- intent than poking at uname or /proc/cpuinfo.
-
- For the moment, we have only optimizations for the Intel generations,
- but that could change... */
-
-#define ELF_PLATFORM (NULL)
-
#ifdef __KERNEL__
#ifdef __powerpc64__