[PATCH 00/11] Add L2 cache cleaning to generic CPU suspend
santosh.shilimkar at ti.com
Sat Sep 3 12:36:38 EDT 2011
On Thursday 01 September 2011 06:17 PM, Russell King - ARM Linux wrote:
> Some systems (such as OMAP) preserve the L2 cache across a suspend/
> resume cycle. This means they do not perform L2 cache maintanence
> in their suspend finisher function.
> However, the side effect is that the saved CPU state is not readable
> by the resume code because it is sitting in the L2 cache.
> This patch series adds L2 cache cleaning to the generic CPU suspend/
> resume support code, making it possible to use this on systems with
> L2 cache enabled without having to clean/invalidate the entire L2
> We also add a separate page table, allocated at boot time, for the
> resume process to use so we don't have to fiddle about with tweaking
> entries in the current processes page table. Moreover, the current
> processes page table may be in use by another CPU in the system if
> these paths are used from cpuidle or hotplug, so changing the page
> table is technically unsound.
> Overall, this makes it possible for OMAP4 systems to use this code.
> The first four patches in this set are already merged into Linus' tree
> as bug fixes, and are included here for completeness given that the
> kernel.org infrastructure is currently offline.
> This has (so far) only been tested on OMAP4. Further testing on OMAP3
> and Assabet will follow.
Thanks a lot Russell for this series. I have tested the entire series
with OMAP4 S2R and CPUIDLE and it works great.
Tested-by: Santosh Shilimkar <santosh.shilimkar at ti.com>
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