linux-toradex.git/arch/arc/kernel/unaligned.c, branch v3.10.32 Linux kernel for Apalis and Colibri modules ARC: Handle zero-overhead-loop in unaligned access handler 2013-10-18T14:45:45+00:00 Mischa Jonker mjonker@synopsys.com 2013-09-26T13:44:56+00:00 5cd12e7776183668bd92a5f5fe102113d3bb599a commit c11eb222fd7d4db91196121dbf854178505d2751 upstream. If a load or store is the last instruction in a zero-overhead-loop, and it's misaligned, the loop would execute only once. This fixes that problem. Signed-off-by: Mischa Jonker <mjonker@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c11eb222fd7d4db91196121dbf854178505d2751 upstream.

If a load or store is the last instruction in a zero-overhead-loop, and
it's misaligned, the loop would execute only once.

This fixes that problem.

Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARC: Unaligned access emulation 2013-02-15T17:46:06+00:00 Vineet Gupta vgupta@synopsys.com 2013-01-23T11:00:36+00:00 2e651ea1596b0ee25af4fcdc4cd13cbb33ffc254 ARC700 doesn't natively support unaligned access, but can be emulated -Unaligned Access Exception -Disassembly at the Fault address to find the exact insn (long/short) Also per Arnd's comment, we runtime control it using 2 sysctl knobs: * SYSCTL_ARCH_UNALIGN_ALLOW: Runtime enable/disble * SYSCTL_ARCH_UNALIGN_NO_WARN: Warn on each emulation attempt Originally contributed by Tim Yao <tim.yao@amlogic.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Tim Yao <tim.yao@amlogic.com> Acked-by: Arnd Bergmann <arnd@arndb.de> 
ARC700 doesn't natively support unaligned access, but can be emulated
-Unaligned Access Exception
-Disassembly at the Fault address to find the exact insn (long/short)

Also per Arnd's comment, we runtime control it using 2 sysctl knobs:
* SYSCTL_ARCH_UNALIGN_ALLOW: Runtime enable/disble
* SYSCTL_ARCH_UNALIGN_NO_WARN: Warn on each emulation attempt

Originally contributed by Tim Yao <tim.yao@amlogic.com>

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Tim Yao <tim.yao@amlogic.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>