12.1. TF-A Memory Layout Tool
TF-A’s memory layout tool is a Python script for analyzing the virtual memory layout of TF-A builds.
12.1.1. Prerequisites
Python (3.8 or later)
Poetry Python package manager
12.1.2. Getting Started
Install Poetry
curl -sSL https://install.python-poetry.org | python3 -
Install the required packages
poetry install --with memory
Verify that the tool runs in the installed virtual environment
poetry run memory --help
12.1.3. Symbol Virtual Map
The tool can be used to generate a visualisation of the symbol table. By default, it prints the symbols representing the start and end address of the main memory regions in an ELF file (i.e. text, bss, rodata) but can be modified to print any set of symbols.
$ poetry run memory -s
build-path: build/fvp/release
Virtual Address Map:
+------------__BL1_RAM_END__------------+---------------------------------------+
+---------__COHERENT_RAM_END__----------+ |
+--------__COHERENT_RAM_START__---------+ |
0x0403b000 +----------__XLAT_TABLE_END__-----------+ |
0x04036000 +---------__XLAT_TABLE_START__----------+ |
+--------__BASE_XLAT_TABLE_END__--------+ |
0x04035600 +--------------__BSS_END__--------------+ |
+-------__BASE_XLAT_TABLE_START__-------+ |
+-----__PMF_PERCPU_TIMESTAMP_END__------+ |
+---------__PMF_TIMESTAMP_END__---------+ |
0x04035400 +--------__PMF_TIMESTAMP_START__--------+ |
+-------------__BSS_START__-------------+ |
0x04034a00 +------------__STACKS_END__-------------+ |
0x04034500 +-----------__STACKS_START__------------+ |
0x040344c5 +-----------__DATA_RAM_END__------------+ |
+-----------__BL1_RAM_START__-----------+ |
0x04034000 +----------__DATA_RAM_START__-----------+ |
| +---------__COHERENT_RAM_END__----------+
| +--------__COHERENT_RAM_START__---------+
0x0402e000 | +----------__XLAT_TABLE_END__-----------+
0x04029000 | +---------__XLAT_TABLE_START__----------+
| +--------__BASE_XLAT_TABLE_END__--------+
0x04028800 | +--------------__BSS_END__--------------+
| +-------__BASE_XLAT_TABLE_START__-------+
| +-----__PMF_PERCPU_TIMESTAMP_END__------+
| +---------__PMF_TIMESTAMP_END__---------+
0x04028580 | +--------__PMF_TIMESTAMP_START__--------+
0x04028000 | +-------------__BSS_START__-------------+
0x04027e40 | +------------__STACKS_END__-------------+
0x04027840 | +-----------__STACKS_START__------------+
0x04027000 | +------------__RODATA_END__-------------+
| +------------__CPU_OPS_END__------------+
| +-----------__CPU_OPS_START__-----------+
| +--------__FCONF_POPULATOR_END__--------+
| +--------------__GOT_END__--------------+
| +-------------__GOT_START__-------------+
| +---------__PMF_SVC_DESCS_END__---------+
0x04026c10 | +--------__PMF_SVC_DESCS_START__--------+
0x04026bf8 | +-------__FCONF_POPULATOR_START__-------+
| +-----------__RODATA_START__------------+
0x04026000 | +-------------__TEXT_END__--------------+
0x04021000 | +------------__TEXT_START__-------------+
0x000062b5 +------------__BL1_ROM_END__------------+ |
0x00005df0 +----------__DATA_ROM_START__-----------+ |
+------------__CPU_OPS_END__------------+ |
+--------------__GOT_END__--------------+ |
+-------------__GOT_START__-------------+ |
0x00005de8 +------------__RODATA_END__-------------+ |
+-----------__CPU_OPS_START__-----------+ |
+--------__FCONF_POPULATOR_END__--------+ |
+---------__PMF_SVC_DESCS_END__---------+ |
0x00005c98 +--------__PMF_SVC_DESCS_START__--------+ |
0x00005c80 +-------__FCONF_POPULATOR_START__-------+ |
+-----------__RODATA_START__------------+ |
0x00005000 +-------------__TEXT_END__--------------+ |
0x00000000 +------------__TEXT_START__-------------+---------------------------------------+
Addresses are displayed in hexadecimal by default but can be printed in decimal
instead with the -d option.
Because of the length of many of the symbols, the tool defaults to a text width
of 120 chars. This can be increased if needed with the -w option.
For more detailed help instructions, run:
poetry run memory --help
12.1.4. Memory Footprint
The tool enables users to view static memory consumption. When the options
-f, or --footprint are provided, the script analyses the ELF binaries in
the build path to generate a table (per memory type), showing memory allocation
and usage. This is the default output generated by the tool.
$ poetry run memory -f
build-path: build/fvp/release
+----------------------------------------------------------------------------+
| Memory Usage (bytes) [RAM] |
+-----------+------------+------------+------------+------------+------------+
| Component | Start | Limit | Size | Free | Total |
+-----------+------------+------------+------------+------------+------------+
| BL1 | 4034000 | 4040000 | 7000 | 5000 | c000 |
| BL2 | 4021000 | 4034000 | d000 | 6000 | 13000 |
| BL2U | 4021000 | 4034000 | a000 | 9000 | 13000 |
| BL31 | 4003000 | 4040000 | 1e000 | 1f000 | 3d000 |
+-----------+------------+------------+------------+------------+------------+
+----------------------------------------------------------------------------+
| Memory Usage (bytes) [ROM] |
+-----------+------------+------------+------------+------------+------------+
| Component | Start | Limit | Size | Free | Total |
+-----------+------------+------------+------------+------------+------------+
| BL1 | 0 | 4000000 | 5df0 | 3ffa210 | 4000000 |
+-----------+------------+------------+------------+------------+------------+
The script relies on symbols in the symbol table to determine the start, end, and limit addresses of each bootloader stage.
12.1.5. Memory Tree
A hierarchical view of the memory layout can be produced by passing the option
-t or --tree to the tool. This gives the start, end, and size of each
module, their ELF segments as well as sections.
$ poetry run memory -t
build-path: build/fvp/release
name start end size
bl1 0 400c000 400c000
├── 00 0 5de0 5de0
│ ├── .text 0 5000 5000
│ └── .rodata 5000 5de0 de0
├── 01 4034000 40344c5 4c5
│ └── .data 4034000 40344c5 4c5
├── 02 4034500 4034a00 500
│ └── .stacks 4034500 4034a00 500
├── 04 4034a00 4035600 c00
│ └── .bss 4034a00 4035600 c00
└── 03 4036000 403b000 5000
└── .xlat_table 4036000 403b000 5000
bl2 4021000 4034000 13000
├── 00 4021000 4027000 6000
│ ├── .text 4021000 4026000 5000
│ └── .rodata 4026000 4027000 1000
└── 01 4027000 402e000 7000
├── .data 4027000 4027809 809
├── .stacks 4027840 4027e40 600
├── .bss 4028000 4028800 800
└── .xlat_table 4029000 402e000 5000
bl2u 4021000 4034000 13000
├── 00 4021000 4025000 4000
│ ├── .text 4021000 4024000 3000
│ └── .rodata 4024000 4025000 1000
└── 01 4025000 402b000 6000
├── .data 4025000 4025065 65
├── .stacks 4025080 4025480 400
├── .bss 4025600 4025c00 600
└── .xlat_table 4026000 402b000 5000
bl31 4003000 4040000 3d000
├── 02 ffe00000 ffe03000 3000
│ └── .el3_tzc_dram ffe00000 ffe03000 3000
├── 00 4003000 4010000 d000
│ └── .text 4003000 4010000 d000
└── 01 4010000 4021000 11000
├── .rodata 4010000 4012000 2000
├── .data 4012000 401219d 19d
├── .stacks 40121c0 40161c0 4000
├── .bss 4016200 4018c00 2a00
├── .xlat_table 4019000 4020000 7000
└── .coherent_ram 4020000 4021000 1000
The granularity of this view can be modified with the --depth option. For
instance, if you only require the tree up to the level showing segment data,
you can specify the depth with:
$ poetry run memory -t --depth 2
build-path: build/fvp/release
name start end size
bl1 0 400c000 400c000
├── 00 0 5df0 5df0
├── 01 4034000 40344c5 4c5
├── 02 4034500 4034a00 500
├── 04 4034a00 4035600 c00
└── 03 4036000 403b000 5000
bl2 4021000 4034000 13000
├── 00 4021000 4027000 6000
└── 01 4027000 402e000 7000
bl2u 4021000 4034000 13000
├── 00 4021000 4025000 4000
└── 01 4025000 402b000 6000
bl31 4003000 4040000 3d000
├── 02 ffe00000 ffe03000 3000
├── 00 4003000 4010000 d000
└── 01 4010000 4021000 11000
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