ARM: 8833/1: Ensure that NEON code always compiles with Clang

[mirror_ubuntu-bionic-kernel.git] / Documentation / arm / kernel_mode_neon.txt

diff --git a/Documentation/arm/kernel_mode_neon.txt b/Documentation/arm/kernel_mode_neon.txt
index 525452726d31e94c43d7c8c7c05c4431b006912a..b9e060c5b61e08c1491c710adc560530b8bae03e 100644 (file)
--- a/Documentation/arm/kernel_mode_neon.txt
+++ b/Documentation/arm/kernel_mode_neon.txt
@@ -6,7 +6,7 @@ TL;DR summary
 * Use only NEON instructions, or VFP instructions that don't rely on support
   code
 * Isolate your NEON code in a separate compilation unit, and compile it with
-  '-mfpu=neon -mfloat-abi=softfp'
+  '-march=armv7-a -mfpu=neon -mfloat-abi=softfp'
 * Put kernel_neon_begin() and kernel_neon_end() calls around the calls into your
   NEON code
 * Don't sleep in your NEON code, and be aware that it will be executed with
@@ -87,7 +87,7 @@ instructions appearing in unexpected places if no special care is taken.
 Therefore, the recommended and only supported way of using NEON/VFP in the
 kernel is by adhering to the following rules:
 * isolate the NEON code in a separate compilation unit and compile it with
-  '-mfpu=neon -mfloat-abi=softfp';
+  '-march=armv7-a -mfpu=neon -mfloat-abi=softfp';
 * issue the calls to kernel_neon_begin(), kernel_neon_end() as well as the calls
   into the unit containing the NEON code from a compilation unit which is *not*
   built with the GCC flag '-mfpu=neon' set.