Add 'MAX_MMAP_REGIONS' and 'ADDR_SPACE_SIZE' to the Porting Guide

This patch adds a brief description of 'MAX_MMAP_REGIONS' and
'ADDR_SPACE_SIZE' to the Porting Guide. These fields must be defined
by the platform in order to use the translation table library.

Change-Id: Ida366458fe2bc01979091a014dc38da0fae5991e
This commit is contained in:
Juan Castillo 2016-01-07 11:29:15 +00:00
parent 5773b5322d
commit 359b60d91c
1 changed files with 16 additions and 0 deletions

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@ -413,6 +413,22 @@ constant must also be defined:
used, choose the smallest value needed to map the required virtual addresses
for each BL stage.
* **#define : MAX_MMAP_REGIONS**
Defines the maximum number of regions that are allocated by the translation
table library code. A region consists of physical base address, virtual base
address, size and attributes (Device/Memory, RO/RW, Secure/Non-Secure), as
defined in the `mmap_region_t` structure. The platform defines the regions
that should be mapped. Then, the translation table library will create the
corresponding tables and descriptors at runtime. To minimize the amount of
runtime memory used, choose the smallest value needed to register the
required regions for each BL stage.
* **#define : ADDR_SPACE_SIZE**
Defines the total size of the address space in bytes. For example, for a 32
bit address space, this value should be `(1ull << 32)`.
If the platform port uses the IO storage framework, the following constants
must also be defined: