Debug Communication Channel (DCC) provides the way how to pass data between target CPU and host via JTAG interface. Every CPU has own interface for communication via dbgdtrtx_el0 and dbgdtrrx_el0 registers. Signed-off-by: Michal Simek <michal.simek@amd.com> Reviewed-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/9d7e85914eb1cdb313b28cb019093a84dd9b4773.1703167505.git.michal.simek@amd.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>