The following are the requirements related to SBSA UART [1] emulated and exposed by Xen to Arm64 domains.

1 Probe the UART device tree node from a domain

XenSwdgn~arm64_uart_probe_dt~1

Description: Xen shall generate a device tree node for the SBSA UART (in accordance to Arm SBSA UART device tree binding [2]) in the domain device tree.

Rationale:

Comments: Domains can detect the presence of the SBSA UART device tree node.

Covers:

• XenProd~emulated_uart~1

2 Transmit data in software polling mode

XenSwdgn~arm64_uart_transmit_data_poll_mode~1

Description: Xen shall support transmission of data in polling mode.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

3 Transmit data in interrupt driven mode

XenSwdgn~arm64_uart_transmit_data_interrupt_mode~1

Description: Xen shall support transmission of data in interrupt driven mode.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

4 Receive data in software polling mode

XenSwdgn~arm64_uart_receive_data_polling_mode~1

Description: Xen shall support reception of data in polling mode.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

5 Receive data in interrupt driven mode

XenSwdgn~arm64_uart_receive_data_interrupt_mode~1

Description: Xen shall support reception of data in interrupt driven mode.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

6 Access UART data register

XenSwdgn~arm64_uart_access_data_register~1

Description: Xen shall emulate the UARTDR register.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

7 Access UART receive status register

XenSwdgn~arm64_uart_access_receive_status_register~1

Description: Xen shall emulate the UARTRSR register.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

8 Access UART flag register

XenSwdgn~arm64_uart_access_flag_register~1

Description: Xen shall emulate the UARTFR register.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

9 Access UART mask set/clear register

XenSwdgn~arm64_uart_access_mask_register~1

Description: Xen shall emulate the UARTIMSC register.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

10 Access UART raw interrupt status register

XenSwdgn~arm64_uart_access_raw_interrupt_status_register~1

Description: Xen shall emulate the UARTRIS register.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

11 Access UART masked interrupt status register

XenSwdgn~arm64_uart_access_mask_irq_status_register~1

Description: Xen shall emulate the UARTMIS register.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

12 Access UART interrupt clear register

XenSwdgn~arm64_uart_access_irq_clear_register~1

Description: Xen shall emulate the UARTICR register.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

13 Receive UART TX interrupt

XenSwdgn~arm64_uart_receive_tx_irq~1

Description: Xen shall generate UART interrupt when the UART transmit interrupt condition is met.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

14 Receive UART RX interrupt reception

XenSwdgn~arm64_uart_receive_rx_irq~1

Description: Xen shall generate UART interrupt when the UART receive interrupt condition is met.

Rationale:

Comments:

Covers:

• XenProd~emulated_uart~1

[1] Arm Base System Architecture, chapter B [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/serial/arm_sbsa_uart.txt