[PATCH rtems-docs] bsps/raspberrypi: Change firmware version, add SPI & I2C support

[Kinsey Moore]

Looks good to me.


Kinsey

On 8/16/2021 05:27, pranav wrote:
> ---
>   user/bsps/arm/raspberrypi.rst | 51 ++++++++++++++++++++++++++++++-----
>   1 file changed, 45 insertions(+), 6 deletions(-)
>
> diff --git a/user/bsps/arm/raspberrypi.rst b/user/bsps/arm/raspberrypi.rst
> index c26f4b5..11dcc30 100644
> --- a/user/bsps/arm/raspberrypi.rst
> +++ b/user/bsps/arm/raspberrypi.rst
> @@ -5,8 +5,9 @@
>   raspberrypi
>   ===========
>   
> -This BSP supports `Raspberry Pi 1` and `Raspberry Pi 2` currently.
> -The support for `Raspberry Pi 3` is work under progress.
> +The 'raspberrypi' BSP supports the single core models (Zero,  Zero W, A+, B+),
> +and the 'raspberrypi2' BSP supports the Raspberry Pi 2, Raspberry Pi 3 A+, and Raspberry Pi 3.
> +The Raspberry Pi 4 is not supported currently.
>   The default bootloader on the Raspberry Pi which is used to boot Raspbian
>   or other OS can be also used to boot RTEMS. U-boot can also be used.
>   
> @@ -19,10 +20,12 @@ The bootloader looks for a kernel image, by default the kernel images must
>   have a name of the form ``kernel*.img`` but this can be changed by adding
>   `kernel=<img_name>` to ``config.txt``.
>   
> -You must provide the required files for the GPU to proceed. These files
> +You must provide the required firmware files on the SD card for the GPU to proceed,
> +and thereby to boot RTEMS.
> +The BSP currently boots up with an older version of the official firmware. These files
>   can be downloaded from
> -`the Raspberry Pi Firmware Repository <https://github.com/raspberrypi/firmware/tree/master/boot>`_.
> -You can remove the ``kernel*.img`` files if you want too, but don't touch
> +`the Raspberry Pi Firmware Repository <https://github.com/raspberrypi/firmware/tree/1.20200601/boot>`_.
> +You can remove the ``kernel*.img`` files if you want to, but don't touch
>   the other files.
>   
>   Copy these files in to a SD card with FAT filesystem.
> @@ -46,10 +49,46 @@ Make sure you have these lines below, in your ``config.txt``.
>   
>   .. code-block:: none
>   
> -     enable_uart=1
> +     dtoverlay=disable-bt
>        kernel_address=0x200000
>        kernel=kernel.img
>   
> +SPI Driver
> +------------
> +
> +SPI drivers are registered by the ``rpi_spi_init(bool bidirectional_mode)`` function.
> +
> +.. code-block:: none
> +
> +     #include <assert.h>
> +     #include <bsp.h>
> +
> +     void spi_init(void)
> +     {
> +       int rv;
> +
> +       rv = rpi_spi_init(false);
> +       assert(rv == 0);
> +     }
> +
> +I2C Driver
> +------------
> +
> +I2C drivers are registered by the ``rpi_setup_i2c_bus()`` function.
> +
> +.. code-block:: none
> +
> +     #include <assert.h>
> +     #include <bsp.h>
> +
> +     void i2c_init(void)
> +     {
> +       int rv;
> +
> +       rv = rpi_setup_i2c_bus();
> +       assert(rv == 0);
> +     }
> +
>   Testing using QEMU
>   ------------------
>