opensbi.git/lib/utils/serial, branch master

lib: utils/serial: Add support for Altera JTAG UART

2026-02-20T11:20:35Z

Altera provides a JTAG UART core that provides virtual UART over JTAG and can coexist with their virtual JTAG. [1] This core has already been supported by Linux and the programming interface has always been stable. Add support for it to OpenSBI to ease JTAG prototype bringing up. The driver follows the device tree binding in mainline Linux. [2] [1] https://docs.altera.com/r/docs/683130/25.3/embedded-peripherals-ip-user-guide/jtag-uart-core [2] https://github.com/torvalds/linux/blob/v6.19-rc1/Documentation/devicetree/bindings/serial/altr%2Cjuart-1.0.yaml Signed-off-by: Icenowy Zheng Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20260104065506.70182-1-zhengxingda@iscas.ac.cn Signed-off-by: Anup Patel

lib: utils/serial: Support multiple UART8250 devices

2025-12-21T15:32:44Z

Previously we assume only 1 UART8250 instance can be used. Now we support multiple instances by introducing counterpart functions to putc/getc/init which take an extra *dev parameter, and name them as uart8250_device_xyz() The original functions without the *dev parameter will operate on the default instance exactly the same as before, so no changes on the caller is required. Note: uart8250_device_init only does device initialization without the console registration logic. Signed-off-by: Bo Gan Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20251218104243.562667-7-ganboing@gmail.com Signed-off-by: Anup Patel

lib: utils/serial: typo Recieve

2025-11-10T08:13:27Z

%s/Recieve/Receive/ Signed-off-by: Heinrich Schuchardt Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20251105011648.9413-1-heinrich.schuchardt@canonical.com Signed-off-by: Anup Patel

lib: serial: sifive-uart: add shared memory region for SiFive UART

2025-10-06T05:43:20Z

Add shared memory region so the driver has permission to access it in OpenSBI. Signed-off-by: Yu-Chien Peter Lin Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20250814111012.20151-1-peter.lin@sifive.com Signed-off-by: Anup Patel

lib: utils/serial: Clear LSR status and check RBR status

2025-07-20T15:07:18Z

On some platforms, read RBR when it is empty may result in an error. Signed-off-by: Yi Pei Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/CAFPVDjQZ1gpf8-u--RBbAL1Y0FfDN2vZ3g=wBw+Bp-8ppuz3HA@mail.gmail.com Signed-off-by: Anup Patel

lib: utils/serial: Add PXA UARTs support

2025-03-27T14:50:05Z

The PXA variant of the uart8250 adds the UART Unit Enable bit (UUE) that needs to be set to enable the XScale PXA UART. And it is required for some RISC-V SoCs like the Spacemit K1 that implement the PXA UART. This introduces the "intel,xscale-uart" compatible to handle setting the UUE bit. Signed-off-by: Junhui Liu Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20250327-pxa-uart-support-v2-1-c4400c1fcd0b@pigmoral.tech Signed-off-by: Anup Patel

lib: sbi: Avoid GOT indirection for global symbol references

2025-03-24T11:30:59Z

OpenSBI is compiled with -fPIE, which generally implies dynamic linking. This causes the compiler to generate GOT references for global symbols in order to support runtime symbol interposition. However, OpenSBI does not actually perform dynamic linking, so the GOT indirection just adds unnecessary overhead. The GOT references can be avoided by declaring global symbols with hidden visibility, thus making them local to this dynamic object and non-interposable. GCC/Clang's -fvisibility parameter is insufficient for this purpose when referencing objects from other translation units; either __attribute__((visibility(...)) or the pragma is required. Use the pragma since it is easier to apply to every symbol. Additionally clean up the one GOT reference from inline assembly. With this change, a firmware linked with LLD does not contain either a GOT or a PLT, and a firmware linked with BFD ld contains only a GOT with a single (unreferenced, legacy) _GLOBAL_OFFSET_TABLE_ entry. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

lib: utils/serial: Use fdt_driver for initialization

2024-11-28T12:22:58Z

The serial driver subsystem does not need any extra data, so it can use `struct fdt_driver` directly. The generic fdt_serial_init() first attempts to match the chosen stdout device, and upon failure matches the first available serial device in the DT. It is a fatal error if no such device is found. This matches the behavior of fdt_driver_init_one(). Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

treewide: Make carray arrays const and NULL-terminated

2024-11-28T11:39:17Z

This allows the compiler to generate significantly better code, because it does not have to maintain either the loop counter or loop limit. Plus there are half as many symbols to relocate. This also simplifies passing carray arrays to helper functions. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

lib: utils/serial: Pass the FDT to fdt_serial_init()

2024-08-24T07:33:01Z

Indicate that this function does not modify the FDT blob, and deduplicate the call to fdt_get_address(). Signed-off-by: Samuel Holland Reviewed-by: Andrew Jones Reviewed-by: Anup Patel