OpenCloudOS-Kernel/arch/arm/vfp
Ard Biesheuvel 73c132c15d ARM: add support for kernel mode NEON
In order to safely support the use of NEON instructions in
kernel mode, some precautions need to be taken:
- the userland context that may be present in the registers (even
  if the NEON/VFP is currently disabled) must be stored under the
  correct task (which may not be 'current' in the UP case),
- to avoid having to keep track of additional vfpstates for the
  kernel side, disallow the use of NEON in interrupt context
  and run with preemption disabled,
- after use, re-enable preemption and re-enable the lazy restore
  machinery by disabling the NEON/VFP unit.

This patch adds the functions kernel_neon_begin() and
kernel_neon_end() which take care of the above. It also adds
the Kconfig symbol KERNEL_MODE_NEON to enable it.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
2013-07-08 22:08:51 +01:00
..
Makefile ARM: vfp: use -mfloat-abi=soft to build vfp 2011-10-01 21:08:55 +02:00
entry.S ARM: 7729/1: vfp: ensure VFP_arch is non-zero when VFP is not supported 2013-05-22 22:01:37 +01:00
vfp.h [ARM] 5387/1: Add ptrace VFP support on ARM 2009-02-12 10:59:43 +00:00
vfpdouble.c [ARM] vfp: fix fuitod/fsitod instructions 2008-01-10 17:07:08 +00:00
vfphw.S ARM: be strict about FP exceptions in kernel mode 2013-07-08 22:07:38 +01:00
vfpinstr.h [ARM] 4583/1: ARMv7: Add VFPv3 support 2008-01-26 14:41:28 +00:00
vfpmodule.c ARM: add support for kernel mode NEON 2013-07-08 22:08:51 +01:00
vfpsingle.c [ARM] Remove unnecessary asm/ptrace.h from VFP support code 2007-04-22 10:56:40 +01:00