On Fri, Mar 26, 2010 at 11:43 AM, Mitch Bradley <w...@firmworks.com> wrote: > Catalin Marinas wrote: >> On Thu, 2010-03-25 at 21:04 +0000, Russell King - ARM Linux wrote: >>> On Wed, Mar 24, 2010 at 09:11:56AM -0600, Grant Likely wrote: >>>> *IRQs disabled >>>> *MMU off >>>> *Instruction cache either on or off >>>> *Data cache turned off >>> >>> Would recommend saying "Data cache(s) turned off" so that L2 cache is >>> included. >> >> There are platforms where the L2 cache is turned on by the boot monitor >> (secure monitor) and Linux has no control over it (I think OMAP). > > What is the reason for turning off the data caches? Leaving all caches > turned on and coherent with one another has always worked well for me at the > interface from firmware to a booted program.
Data cache off is specified in Documentation/arm/Booting in the Linux source tree and I used that document as a starting point to get discussion going. I don't have a technical argument either way. Russell, what is the reason for having the data cache off? g. _______________________________________________ devicetree-discuss mailing list devicetree-discuss@lists.ozlabs.org https://lists.ozlabs.org/listinfo/devicetree-discuss