• Suzuki K Poulose's avatar
    coresight: Add support for CLAIM tag protocol · 2478a6ae
    Suzuki K Poulose authored
    Coresight architecture defines CLAIM tags for a device to negotiate
    control of the components (external agent vs self-hosted). Each device
    has a pair of registers (CLAIMSET & CLAIMCLR) for managing the CLAIM
    tags. However, the protocol for the CLAIM tags is IMPLEMENTATION DEFINED.
    PSCI has recommendations for the use of the CLAIM tags to negotiate
    controls for external agent vs self-hosted use. This patch implements
    the recommended protocol by PSCI.
    
    The claim/disclaim operations are performed from the device specific
    drivers. The disadvantage is that the calls are sprinkled in each driver,
    but this makes the operation much simpler.
    
    Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
    Signed-off-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
    Signed-off-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    2478a6ae