Arrange to use an item from SMEM memory for IPA.  SMEM item number
497 is designated to be used by the IPA.  Specify the item ID and
size of the region in platform configuration data.  Allocate and get
a pointer to this region from ipa_mem_init().  The memory must be
mapped for access through an SMMU.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Define a region of IMEM memory available for use by IPA in the
platform configuration data.  Initialize it from ipa_mem_init().
The memory must be mapped for access through an SMMU.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch includes three source files that represent some basic "main
program" code for the IPA driver.  They are:
  - "ipa.h" defines the top-level IPA structure which represents an IPA
     device throughout the code.
  - "ipa_main.c" contains the platform driver probe function, along with
    some general code used during initialization.
  - "ipa_reg.h" defines the offsets of the 32-bit registers used for the
    IPA device, along with masks that define the position and width of
    fields within these registers.
  - "version.h" defines some symbolic IPA version numbers.

Each file includes some documentation that provides a little more
overview of how the code is organized and used.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>