diff options
| author | Sandrine Bailleux <sandrine.bailleux@arm.com> | 2016-01-13 14:57:38 +0000 |
|---|---|---|
| committer | Sandrine Bailleux <sandrine.bailleux@arm.com> | 2016-02-08 09:31:18 +0000 |
| commit | 54035fc4672aab046f3cf5288ce9870613bd713d (patch) | |
| tree | 211e2343035056381eed8764300c9f76170d63dc /Makefile | |
| parent | dbc807179fea7438efa3374584310727ce44bbc9 (diff) | |
Disable non-temporal hint on Cortex-A53/57
The LDNP/STNP instructions as implemented on Cortex-A53 and
Cortex-A57 do not behave in a way most programmers expect, and will
most probably result in a significant speed degradation to any code
that employs them. The ARMv8-A architecture (see Document ARM DDI
0487A.h, section D3.4.3) allows cores to ignore the non-temporal hint
and treat LDNP/STNP as LDP/STP instead.
This patch introduces 2 new build flags:
A53_DISABLE_NON_TEMPORAL_HINT and A57_DISABLE_NON_TEMPORAL_HINT
to enforce this behaviour on Cortex-A53 and Cortex-A57. They are
enabled by default.
The string printed in debug builds when a specific CPU errata
workaround is compiled in but skipped at runtime has been
generalised, so that it can be reused for the non-temporal hint use
case as well.
Change-Id: I3e354f4797fd5d3959872a678e160322b13867a1
Diffstat (limited to 'Makefile')
| -rw-r--r-- | Makefile | 8 |
1 files changed, 4 insertions, 4 deletions
@@ -1,5 +1,5 @@ # -# Copyright (c) 2013-2015, ARM Limited and Contributors. All rights reserved. +# Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: @@ -294,9 +294,9 @@ ifneq (${ENABLE_PLAT_COMPAT}, 0) include plat/compat/plat_compat.mk endif -# Include the CPU specific operations makefile. By default all CPU errata -# workarounds and CPU specific optimisations are disabled. This can be -# overridden by the platform. +# Include the CPU specific operations makefile, which provides default +# values for all CPU errata workarounds and CPU specific optimisations. +# This can be overridden by the platform. include lib/cpus/cpu-ops.mk |