mirror of
https://github.com/supleed2/EIE4-FYP.git
synced 2024-09-19 21:36:17 +00:00
105 lines
4.1 KiB
Markdown
105 lines
4.1 KiB
Markdown
# Bare Metal Demo App
|
|
|
|
This directory provides a minimal bare metal demo app that demonstrates how to easily create a bare metal C application and load it/run it on the CPU of a SoC.
|
|
|
|
## Build and Load over LiteX-Term
|
|
|
|
To build a LiteX SoC for the Arty board (available in LiteX-Boards) and build the demo app for it, execute the following commands:
|
|
|
|
```bash
|
|
python3 -m litex_boards.targets.digilent_arty --build --load
|
|
litex_bare_metal_demo --build-path=build/digilent_arty
|
|
```
|
|
|
|
Where `--build-path` is the build path to the Arty build directory. The Arty board is used here but almost any another board supported in LiteX-Boards could be used. When no external RAM is provided directly by the board, `--integrated-main-ram-size` argument could be used to add some integrated RAM in the SoC and be able to execute the demo from it. (ex `--integrated-main-ram-size=0x8000` will add 32KB of integrated RAM).
|
|
|
|
Loading the compiled demo app can be done in different ways as explain in LiteX's [wiki](https://github.com/enjoy-digital/litex/wiki/Load-Application-Code-To-CPU)
|
|
|
|
Since our app is small and for simplicity we'll just load it over serial here: `$ litex_term /dev/ttyUSBX --kernel=demo.bin`
|
|
|
|
You should see the minimal demo app running and should be able to interact with it:
|
|
|
|
```shell
|
|
--============== Boot ==================--
|
|
Booting from serial...
|
|
Press Q or ESC to abort boot completely.
|
|
sL5DdSMmkekro
|
|
[LITEX-TERM] Received firmware download request from the device.
|
|
[LITEX-TERM] Uploading demo.bin to 0x40000000 (9264 bytes)...
|
|
[LITEX-TERM] Upload complete (9.8KB/s).
|
|
[LITEX-TERM] Booting the device.
|
|
[LITEX-TERM] Done.
|
|
Executing booted program at 0x40000000
|
|
|
|
--============= Liftoff! ===============--
|
|
|
|
LiteX minimal demo app built Dec 10 2020 17:13:02
|
|
|
|
Available commands:
|
|
help - Show this command
|
|
reboot - Reboot CPU
|
|
led - Led demo
|
|
donut - Spinning Donut demo
|
|
litex-demo-app> led
|
|
Led demo...
|
|
Counter mode...
|
|
Shift mode...
|
|
Dance mode...
|
|
litex-demo-app> donut
|
|
Donut demo...
|
|
|
|
$$$$$@@@@@
|
|
$##########$$$$$$$$
|
|
###*!!!!!!!!!***##$$$$$$
|
|
***!!====;;;;===!!**###$$$$#
|
|
**!===;;;:::::;:===!!**####$##
|
|
!*!!==;;:~-,,.,-~::;;=!!**#######!
|
|
!!!!=;:~-,.......-~::==!!***#####*
|
|
!!!!==;~~-.........,-:;==!!***###**!
|
|
!**!!=;:~-... ..-:;=!!!********!
|
|
;!*#####*!!;. ~:;==!!!******!!=
|
|
:!*###$$$$#*! :;==!!!!!****!!!=;
|
|
~=!*#$$$@@@$$##!!!!!!!!!!!!****!!!!=;
|
|
;=!*#$$$@@@@$$#*******!*!!*!!!!!==;~
|
|
-;!*###$$$$$$$###******!!!!!!!===;~
|
|
-;!!*####$#####******!!!!!!==;;:-
|
|
,:=!!!!**#**#***!!!!!!!====;:~,
|
|
-:==!!!*!!*!!!!!!!===;;;:~-
|
|
.~:;;========;=;;:::~-,
|
|
.--~~::::~:~~--,.
|
|
litex-demo-app>
|
|
```
|
|
|
|
## Replace the LiteX BIOS with the Demo App
|
|
|
|
In some cases, we'll just want to replace the LiteX BIOS with our custom app. This demo can be used as a basis to create a such custom app.
|
|
|
|
The demo will be recompiled to target the ROM of the SoC:
|
|
|
|
```bash
|
|
litex_bare_metal_demo --build-path=build/arty/ --mem=rom
|
|
```
|
|
|
|
The SoC can then be re-compiled to integrate the demo app in the ROM with:
|
|
|
|
```bash
|
|
python3 -m litex_boards.targets.digilent_arty --integrated-rom-init=demo.bin --build --load
|
|
```
|
|
|
|
When loading the bitstream, you should then directly see the demo app executed:
|
|
|
|
```shell
|
|
LiteX minimal demo app built Dec 10 2020 17:13:02
|
|
|
|
Available commands:
|
|
help - Show this command
|
|
reboot - Reboot CPU
|
|
led - Led demo
|
|
donut - Spinning Donut demo
|
|
litex-demo-app>
|
|
```
|
|
|
|
## Going further
|
|
|
|
To create more complex apps, feel free to explore the source code of the BIOS or other open source projects build with LiteX on the [GitHub wiki](https://github.com/enjoy-digital/litex/wiki/Projects).
|