[PATCH v8 2/2] arm-soc: Add support for arm-based tango4 platforms

Marc Gonzalez marc_gonzalez at sigmadesigns.com
Tue Nov 3 00:34:49 PST 2015

Santosh Shilimkar wrote:

> Mark Rutland wrote:
>> We didn't. Having a look just now, the earliest example appears to be
>> in OMAP4 L2 support patches back in 2009 [1]. I was not able to find a
>> rationale.
>> Given that the MMU is on (and speculative accesses are permitted) I
>> can't see what the DSB achieves -- it can't quiesce the memory system.
>> Santosh, any idea?
> IIRC, it was requirement from the OMAP ROM code to have a dsb before
> we call the SMC routine. I can't recollect more than that now.

In that case, shouldn't dsb have been added to the ROM code,
on the "other side" of the smc, so as to not depend on Linux
code "getting it right"?


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