[PATCH v4 1/3] arm64/hwcap: Document allocation of upper bits of AT_HWCAP

[Mark Brown]

The top two bits of AT_HWCAP are reserved for use by glibc and the rest of
the top 32 bits are being kept unallocated for potential use by glibc.
Document this in the header.

Signed-off-by: Mark Brown <broonie at kernel.org>
---
 arch/arm64/include/uapi/asm/hwcap.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h
index 4bb2cc8ac446..cc2ccd0a9edf 100644
--- a/arch/arm64/include/uapi/asm/hwcap.h
+++ b/arch/arm64/include/uapi/asm/hwcap.h
@@ -19,6 +19,9 @@
 
 /*
  * HWCAP flags - for AT_HWCAP
+ *
+ * Bits 60 and 61 are reserved for use by libc.
+ * Bits 32-59 are unallocated for potential use by libc.
  */
 #define HWCAP_FP		(1 << 0)
 #define HWCAP_ASIMD		(1 << 1)
-- 
2.30.2