linux-toradex.git/arch/parisc/lib/delay.c, branch v3.17 Linux kernel for Apalis and Colibri modules parisc: make udelay() SMP-safe 2013-11-07T21:28:26+00:00 Helge Deller deller@gmx.de 2013-10-23T21:29:16+00:00 f6d12eefcda2e4135aa529ab8b5bf2766b4a78dd Each CPU has it's own Control Register 16 (CR16) which is used as time source for the udelay() function. But since the CR16 registers across different CPUs are not synced, we need to recalculate the loop count if we get switched away to ensure that we really delay as much time as requested. Signed-off-by: Helge Deller <deller@gmx.de> 
Each CPU has it's own Control Register 16 (CR16) which is used as time source
for the udelay() function. But since the CR16 registers across different CPUs
are not synced, we need to recalculate the loop count if we get switched away
to ensure that we really delay as much time as requested.

Signed-off-by: Helge Deller <deller@gmx.de>