[PATCH 2/2] powerpc/perf: Add generic compat mode pmu driver

[Michael Ellerman]

On Thu, 2019-04-04 at 11:54:50 UTC, Madhavan Srinivasan wrote:
> Most of the power processor generation performance monitoring
> unit (PMU) driver code is bundled in the kernel and one of those
> is enabled/registered based on the oprofile_cpu_type check at
> the boot.
> 
> But things get little tricky incase of "compat" mode boot.
> IBM POWER System Server based processors has a compactibility
> mode feature, which simpily put is, Nth generation processor
> (lets say POWER8) will act and appear in a mode consistent
> with an earlier generation (N-1) processor (that is POWER7).
> And in this "compat" mode boot, kernel modify the
> "oprofile_cpu_type" to be Nth generation (POWER8). If Nth
> generation pmu driver is bundled (POWER8), it gets registered.
> 
> Key dependency here is to have distro support for latest
> processor performance monitoring support. Patch here adds
> a generic "compat-mode" performance monitoring driver to
> be register in absence of powernv platform specific pmu driver.
> 
> Driver supports only "cycles" and "instruction" events.
> "0x0001e" used as event code for "cycles" and "0x00002"
> used as event code for "instruction" events. New file
> called "generic-compat-pmu.c" is created to contain the driver
> specific code. And base raw event code format modeled
> on PPMU_ARCH_207S.
> 
> Signed-off-by: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/be80e758d0c2ec87eceac7676f08c761

cheers