• Lorenzo Pieralisi's avatar
    drivers: cci: add missing CCI port availability firmware check · 801f33be
    Lorenzo Pieralisi authored
    The CCI ports programming interface is available to the kernel
    only when booted in secure mode (or when firmware enables
    non-secure access to override CCI ports control). In both cases,
    firmware reports the CCI ports availability through the device
    tree CCI ports nodes, which must be parsed and their status checked
    by the kernel probing path.
    
    This check is currently missing and may cause the kernel to
    erroneously believe it is free to take control of CCI ports
    where in practice CCI ports control is forbidden.
    
    Add the missing CCI port availability check to the CCI driver
    in order to guarantee sane CCI usage.
    
    Cc: Liviu Dudau <liviu.dudau@arm.com>
    Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
    Cc: Marc Zyngier <marc.zyngier@arm.com>
    Acked-by: default avatarNicolas Pitre <nico@linaro.org>
    Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
    Signed-off-by: default avatarSudeep Holla <sudeep.holla@arm.com>
    801f33be
arm-cci.c 63.1 KB