• Madhavan Srinivasan's avatar
    powerpc/perf: Add generic compat mode pmu driver · be80e758
    Madhavan Srinivasan authored
    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: default avatarMadhavan Srinivasan <maddy@linux.vnet.ibm.com>
    [mpe: Use SPDX tag for license]
    Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
    be80e758
internal.h 378 Bytes