Now that we have all the necessary information available we can
build the L1 cache shape info to be passed down to userspace via
the ELF AUX vectors.
Signed-off-by: Benjamin Herrenschmidt <b...@kernel.crashing.org>
---
arch/powerpc/kernel/setup_64.c | 34 ++++++++++++++++++++++++++++++++++
1 file changed, 34 insertions(+)
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index d36b6f4..2079e2e 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -382,6 +382,34 @@ void smp_release_cpus(void)
}
#endif /* CONFIG_SMP || CONFIG_KEXEC */
+static long format_cache_shape(u32 size, u32 sets, u32 lsize)
+{
+ long result = 0;
+ u32 log2size = __ilog2(lsize);
+ u32 ways;
+
+ if (size == 0 || sets == 0)
+ return -1;
+ if (sets == 1)
+ ways = 0;
+ else
+ ways = size / (lsize * sets);
+ if (ways < 0x2ff)
+ result |= ways;
+ else
+ result |= 0x2ff;
+ if (log2size < 0xf)
+ result |= (log2size << 10);
+ else
+ result |= 0x3c00;
+ if (size >= 1024)
+ result |= (size >> 10) << 14;
+ else
+ result |= 0xfffffc000ul;
+
+ return result;
+}
+
/*
* Initialize some remaining members of the ppc64_caches and systemcfg
* structures
@@ -487,6 +515,12 @@ void __init initialize_cache_info(void)
/* For use by binfmt_elf */
dcache_bsize = ppc64_caches.dblock_size;
icache_bsize = ppc64_caches.iblock_size;
+ il1cache_shape = format_cache_shape(ppc64_caches.isize,
+ ppc64_caches.isets,
+ ppc64_caches.iline_size);
+ dl1cache_shape = format_cache_shape(ppc64_caches.dsize,
+ ppc64_caches.dsets,
+ ppc64_caches.dline_size);
DBG(" <- initialize_cache_info()\n");
}
--
2.7.4
