Coresight bus and drivers from CodeAurora

[Paul Walmsley]

cc Alex Shishkin

Hi

On Mon, 10 Dec 2012, Will Deacon wrote:

> On Mon, Dec 10, 2012 at 12:40:20PM +0000, Linus Walleij wrote:
> > recently my colleague Magnus (@ST-Ericsson) found this bus and
> > implementations for the ARM Coresight and drivers for the ARM Coresight
> > blocks ETB, ETM, Funnel, Replicator, STM, TMC and TPIU. The
> > code is here:
> > https://www.codeaurora.org/gitweb/quic/le/?p=kernel/msm.git;a=tree;f=drivers/coresight;h=f0221ea9a55c1e8bcd63f36ec28abb6d5406e63d;hb=refs/heads/msm-3.4
> > 
> > What is your intention with this? Do you have any intention to mainline?

Just as an aside, there's also already some support for ETM and ETB in 
mainline in arch/arm/kernel/etm.c.

...

We've used self-hosted tracing in the past for post-mortem kernel 
debugging.  The ARM logs traces to the ETB; the kernel crashes; then upon 
the next reboot, the trace is read from the ETB.


- Paul