+ linux-arm, Russell and Catalin On Mon, Jan 16, 2012 at 11:03 AM, Joe Woodward <jw@xxxxxxxxxxxxxx> wrote: > The latest uBoot release (2011.12) disables the L2/outer cache during boot on OMAP boards. > > uBoot commit: "armv7: disable L2 cache in cleanup_before_linux()" on 6th Dec 2011 by Aneesh V adds the following to > uBootSources/arch/arm/cpu/armv7/cpu.c:cleanup_before_linux(): > ... > v7_out_cache_disable(); > > The commit message implies this change was to make booting reliable on OMAP4 by disabling L2 cache before jumping to Linux. Sadly > this commit also affects OMAP3-based boards... > > Since switching to uBoot 2011.12 I'm seeing about half the performance on my GUSMTIX Overo (OMAP3530). > > In the kernel sources there seem to be OMAP4 specific functions for re-enabling the L2 cache (omap4-common.c:omap_l2_cache_init()), > but none for OMAP3. > > So my question is... do we expect that Linux should be re-enabling the L2/outer cache during boot after uBoot has disabled it on OMAP3? > Yes. Kernel already does enabled L2 on A8 CPU's but OMAP3 needs a secure call and then the patching becomes that much difficult. We need some kind of generic hook in proc*_setup() function where in such secure bits can be turned ON. Regards Santosh -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
