Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

samv7: support RX/TX DMA for UART peripherals #15716

Merged
merged 2 commits into from
Jan 30, 2025
Merged

samv7: support RX/TX DMA for UART peripherals #15716

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
8e58b0f
samv7/serial: allow TX/RX DMA for UART drivers
michallenc Jan 28, 2025
db38122
boards/samv7/common: add support for UART RX DMA polling
michallenc Jan 29, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
10 changes: 6 additions & 4 deletions Documentation/platforms/arm/samv7/index.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -284,10 +284,12 @@ The peripheral implements four timer counter modules, each supporting three inde
Universal Synchronous Asynchronous Receiver Transceiver (USART)
---------------------------------------------------------------

The MCU supports both UART and USART controllers. USART peripheral can be used with TX and RX DMA support.
For RX DMA it is required to configure idle bus timeout value in ``CONFIG_SAMV7_SERIAL_DMA_TIMEOUT``.
This option ensures data are read from the DMA buffer even if it is not full yet. DMA support is
implemented only for USART peripheral and not for UART.
The MCU supports both UART and USART controllers. These peripheral can be used with TX and RX DMA support.
For RX DMA on USART, it is possible to configure idle bus timeout value in ``CONFIG_SAMV7_SERIAL_DMA_TIMEOUT``.
This option ensures data are read from the DMA buffer even if it is not full yet. UART peripherals do not have
this timeout support, therefore function :c:func:`sam_serial_dma_poll` should be called periodically to
flush the DMA buffers. Boards can use common :c:func:`board_uart_rxdma_poll_init` function to initialize
a timer triggering the poll.

There are several modes in which USART peripheral can operate (ISO7816, IrDA, RS485, SPI, LIN and LON).
Currently RS485 and SPI master are supported by NuttX.
Expand Down
Loading
Loading