genode/repos/base/src/core/include/io_mem_session_component.h

/*
 * \brief  Core-specific instance of the IO_MEM session interface
 * \author Christian Helmuth
 * \date   2006-09-14
 */

/*
 * Copyright (C) 2006-2017 Genode Labs GmbH
 *
 * This file is part of the Genode OS framework, which is distributed
 * under the terms of the GNU Affero General Public License version 3.
 */

#ifndef _CORE__INCLUDE__IO_MEM_SESSION_COMPONENT_H_
#define _CORE__INCLUDE__IO_MEM_SESSION_COMPONENT_H_

/* Genode includes */
#include <base/allocator.h>
#include <base/rpc_server.h>
#include <io_mem_session/io_mem_session.h>

/* core includes */
#include <dataspace_component.h>

namespace Genode {

	class Io_mem_session_component : public Rpc_object<Io_mem_session>
	{
		private:

			/*
			 * Helper class used to pass the dataspace attributes as
			 * parameters from the _prepare_io_mem function to the
			 * constructor of Dataspace_component.
			 */
			struct Dataspace_attr
			{
				size_t          size            { 0 };
				addr_t          core_local_addr { 0 };
				addr_t          phys_addr       { 0 };
				Cache_attribute cacheable       { UNCACHED };

				/**
				 * Base address of request used for freeing mem-ranges
				 */
				addr_t req_base { 0 };

				/**
				 * Default constructor
				 *
				 * This constructor enables Dataspace_attr objects to be
				 * returned from the '_prepare_io_mem' function.
				 */
				Dataspace_attr() { }

				/**
				 * Constructor
				 *
				 * An invalid dataspace is represented by setting all
				 * arguments to zero.
				 */
				Dataspace_attr(size_t s, addr_t cla, addr_t pa, Cache_attribute c,
				               addr_t req_base)
				:
					size(s), core_local_addr(cla), phys_addr(pa),
					cacheable(c), req_base(req_base) { }
			};

			struct Io_dataspace_component : Dataspace_component
			{
				addr_t req_base;

				/**
				 * Constructor
				 */
				Io_dataspace_component(Dataspace_attr da)
				:
					Dataspace_component(da.size, da.core_local_addr,
					                    da.phys_addr, da.cacheable,
					                    true, 0),
					req_base(da.req_base) { }


				bool valid() { return size() != 0; }
			};

			Range_allocator            &_io_mem_alloc;
			Io_dataspace_component      _ds;
			Rpc_entrypoint             &_ds_ep;
			Io_mem_dataspace_capability _ds_cap    { };
			Cache_attribute             _cacheable { UNCACHED };

			Dataspace_attr _prepare_io_mem(const char *args, Range_allocator &ram_alloc);


			/********************************************
			 ** Platform-implemented support functions **
			 ********************************************/

			/* FIXME Could this be merged with Dataspace::unmap() and friends? */

			/**
			 * Map region locally and return local base address
			 *
			 * Both parameters - base and size - must be page-aligned.
			 */
			addr_t _map_local(addr_t base, size_t size);

			/**
			 * Unmap Core-local mapping of region
			 *
			 * Both parameters - base and size - must be page-aligned.
			 */
			void _unmap_local(addr_t base, size_t size);

		public:

			/**
			 * Constructor
			 *
			 * \param io_mem_alloc  MMIO region allocator
			 * \param ram_alloc     RAM allocator that will be checked for
			 *                      region collisions
			 * \param ds_ep         entry point to manage the dataspace
			 *                      corresponding the io_mem session
			 * \param args          session construction arguments, in
			 *                      particular MMIO region base, size and
			 *                      caching demands
			 */
			Io_mem_session_component(Range_allocator &io_mem_alloc,
			                         Range_allocator &ram_alloc,
			                         Rpc_entrypoint  &ds_ep,
			                         const char      *args);

			/**
			 * Destructor
			 */
			~Io_mem_session_component();


			/******************************
			 ** Io-mem session interface **
			 ******************************/

			Io_mem_dataspace_capability dataspace() override { return _ds_cap; }
	};
}

#endif /* _CORE__INCLUDE__IO_MEM_SESSION_COMPONENT_H_ */