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authorLinus Torvalds <torvalds@linux-foundation.org>2013-09-05 18:07:32 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-09-05 18:07:32 -0700
commit2e032852245b3dcfe5461d7353e34eb6da095ccf (patch)
tree69f9fdf03b54d76bb539096e0ec96e91ea8216b1 /arch/arm/include/asm/neon.h
parent356f9e74ffaafd11741589a9aa21d6c9d2721417 (diff)
parent141b97433d77e39ac3ac111a7b3852192035259c (diff)
downloadlinux-2e032852245b3dcfe5461d7353e34eb6da095ccf.tar.bz2
Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM updates from Russell King: "This set includes adding support for Neon acceleration of RAID6 XOR code from Ard Biesheuvel, cache flushing and barrier updates from Will Deacon, and a cleanup to the ARM debug code which reduces the amount of code by about 500 lines. A few other cleanups, such as constifying the machine descriptors which already shouldn't be written to, cleaning up the printing of the L2 cache size" * 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (55 commits) ARM: 7826/1: debug: support debug ll on hisilicon soc ARM: 7830/1: delay: don't bother reporting bogomips in /proc/cpuinfo ARM: 7829/1: Add ".text.unlikely" and ".text.hot" to arm unwind tables ARM: 7828/1: ARMv7-M: implement restart routine common to all v7-M machines ARM: 7827/1: highbank: fix debug uart virtual address for LPAE ARM: 7823/1: errata: workaround Cortex-A15 erratum 773022 ARM: 7806/1: allow DEBUG_UNCOMPRESS for Tegra ARM: 7793/1: debug: use generic option for ep93xx PL10x debug port ARM: debug: move SPEAr debug to generic PL01x code ARM: debug: move davinci debug to generic 8250 code ARM: debug: move keystone debug to generic 8250 code ARM: debug: remove DEBUG_ROCKCHIP_UART ARM: debug: provide generic option choices for 8250 and PL01x ports ARM: debug: move PL01X debug include into arch/arm/include/debug/ ARM: debug: provide PL01x debug uart phys/virt address configuration options ARM: debug: add support for word accesses to debug/8250.S ARM: debug: move 8250 debug include into arch/arm/include/debug/ ARM: debug: provide 8250 debug uart phys/virt address configuration options ARM: debug: provide 8250 debug uart register shift configuration option ARM: debug: provide 8250 debug uart flow control configuration option ...
Diffstat (limited to 'arch/arm/include/asm/neon.h')
-rw-r--r--arch/arm/include/asm/neon.h36
1 files changed, 36 insertions, 0 deletions
diff --git a/arch/arm/include/asm/neon.h b/arch/arm/include/asm/neon.h
new file mode 100644
index 000000000000..8f730fe70093
--- /dev/null
+++ b/arch/arm/include/asm/neon.h
@@ -0,0 +1,36 @@
+/*
+ * linux/arch/arm/include/asm/neon.h
+ *
+ * Copyright (C) 2013 Linaro Ltd <ard.biesheuvel@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <asm/hwcap.h>
+
+#define cpu_has_neon() (!!(elf_hwcap & HWCAP_NEON))
+
+#ifdef __ARM_NEON__
+
+/*
+ * If you are affected by the BUILD_BUG below, it probably means that you are
+ * using NEON code /and/ calling the kernel_neon_begin() function from the same
+ * compilation unit. To prevent issues that may arise from GCC reordering or
+ * generating(1) NEON instructions outside of these begin/end functions, the
+ * only supported way of using NEON code in the kernel is by isolating it in a
+ * separate compilation unit, and calling it from another unit from inside a
+ * kernel_neon_begin/kernel_neon_end pair.
+ *
+ * (1) Current GCC (4.7) might generate NEON instructions at O3 level if
+ * -mpfu=neon is set.
+ */
+
+#define kernel_neon_begin() \
+ BUILD_BUG_ON_MSG(1, "kernel_neon_begin() called from NEON code")
+
+#else
+void kernel_neon_begin(void);
+#endif
+void kernel_neon_end(void);