NVIDIA/lstp-config

NVIDIA/lstp-config

Description: LSTP device configuration tool

Language: C

License: Apache-2.0

Stars: 0

Forks: 0

Open issues: 0

Created: 2026-07-14T00:51:28Z

Pushed: 2026-08-12T22:47:20Z

Default branch: main

Fork: no

Archived: no

README:

lstp_config_tool

Userspace LSTP configuration tool: READ_CONFIG / WRITE_CONFIG over libusb, with YAML read and write via libyaml. See [LSTP Specification 1.0.pdf](LSTP%20Specification%201.0.pdf) for more details on LSTP.

The tool only touches sysfs to temporarily unbind the normal lstp driver so libusb can claim the interface, then restores lstp on exit if it was bound at start.

Licensed under the Apache License 2.0 — see [LICENSE](LICENSE).

Build

make produces up to two deployable outputs when the required compilers are installed; missing cross-compilers are skipped (not an error).

| Binary | Architecture | Typical target | |--------|--------------|----------------| | build/lstp_config_tool_x86 | x86_64 | Intel/AMD laptop, dev VM | | build/lstp_config_tool_ARM | armhf (ARMv7 hard-float) | OpenBMC AST2600 / ARM BMCs |

The ARM binary is built for armv7-a (AST2600). On 64-bit ARM hosts (e.g. RPi 3+, some OpenBMC images), it runs via kernel 32-bit compat when enabled.

Install cross-compilers once, then build from x86_64, aarch64, or armv7l:

sudo apt install gcc-arm-linux-gnueabihf gcc-x86-64-linux-gnu
make clean-all
make
file build/lstp_config_tool_x86 build/lstp_config_tool_ARM
ldd build/lstp_config_tool_ARM # not a dynamic executable

On x86_64, native gcc builds build/lstp_config_tool_x86; armhf is cross-compiled when gcc-arm-linux-gnueabihf is installed.

On aarch64, armhf and x86 are cross-compiled when their packages are installed.

On armv7l (32-bit ARM), native gcc builds build/lstp_config_tool_ARM; x86 is cross-compiled when gcc-x86-64-linux-gnu is installed.

make # x86 + arm when compilers are installed
make x86 # x86_64 only
make arm # build/lstp_config_tool_ARM only

Run

--usb-path and either --read or --write are required (sysfs interface id). Root (sudo) is required for driver unbind and USB access.

Read

Read all channels from the device and write YAML:

sudo ./build/lstp_config_tool_ARM -u 1-1.1:1.2 -r

If FILE is omitted, the output filename is derived from the management channel name before the first _:

sudo ./build/lstp_config_tool_ARM -u 1-1.1:1.2 -r out.yaml

Read path:

1. READ_CONFIG on channel 0 (management), then channels 1..num_channels 2. READ_CONFIG_MODE on channel 0 (included in YAML as lock_state) 3. Write YAML (schema_version: 1)

Write

Load a YAML file and WRITE_CONFIG to the device. When lock_state is nonvolatile or locked, the tool prompts for confirmation before touching the device (skipped with -y). Non-volatile writes may consume OTP space on devices without flash firmware; locked mode permanently fuses the config and cannot be undone.

sudo ./build/lstp_config_tool_ARM -u 1-1.1:1.2 -w write.yaml

-r / --read and -w / --write are mutually exclusive.

Options

| Option | Description | |--------|-------------| | -u, --usb-path PATH | Required sysfs interface id (e.g. 1-1.1:1.2) | | -r, --read [FILE] | Read config from device and write YAML (default FILE: .yaml) | | -w, --write FILE | Load YAML and WRITE_CONFIG to device | | -y, --yes | With --write: skip confirmation for lock_state nonvolatile or locked | | -d, --debug | Verbose USB/protocol logging | | -h, --help | Usage |

YAML

• Root: schema_version: 1, channels: map keyed by channel id
• Channel 0: type: management, lock_state: nonvolatile\|locked\|volatile, plus config.lstp_version and config.num_channels
• Data channels: type-specific config (GPIO, I2C, UART, SPI, etc.)
• READ_CONFIG output is normalized to the current schema. Newer firmware may return bytes beyond the current known config layout; the tool drops those bytes, prints a warning, and does not preserve them in YAML. Any other unexpected read size fails the read.
• WRITE_CONFIG sends only fields this tool understands. Valid current YAML may still fail on a target board if the config state is locked/fused or firmware rejects an unsupported option, nonexistent offset, or size policy.
• Write validation is strict: every schema field must be present with a valid value; channel count must match num_channels
• Optional YAML document markers (--- at the top, ... at the end) are ignored by the parser; only schema_version and channels content matter. Files under sample_config/ may include them for readability.

Write-time value checks (selected)

| Channel | Field | Allowed values | |---------|-------|----------------| | SPI | num_devices | 1–2 | | SPI | clock_speed_hz | non-zero | | SPI | output_drive_strength_ma, slew_rate, input_debounce_us, glitch_filter_width_ns | 0–65535 | | I2C | speed | 100k, 400k, 1m, or 3p4m | | I2C | output_drive_strength_ma, slew_rate, input_debounce_us, glitch_filter_width_ns | 0–65535 | | I2C | bus_low_timeout_ms, bus_arbitration_retries | 0–255 | | UART | baud_rate | non-zero | | UART | data_bits | 5–8 | | UART | stop_bits | 1 or 2 | | UART | parity | none, odd, even, mark, or space | | UART | flow_control | none, xon_xoff, rts_cts, or dtr_dsr | | UART | output_drive_strength_ma, slew_rate, input_debounce_us, glitch_filter_width_ns | 0–65535 | | GPIO | ngpio | 1–255 per block | | GPIO pin | name | non-empty | | GPIO pin | default_output | low, high, or z | | GPIO pin | numeric fields | within wire limits (uint16 where applicable) |

Invalid wire blobs are also rejected immediately before WRITE_CONFIG.

Example files in the repo:

| File | Description | |------|-------------| | sample_config/lstp_config.yaml | YAML schema stub (top-level shape) | | sample_config/sample_config_schema.yaml | Per-channel config field reference (all types) | | sample_config/sample_all_channels.yaml | Reference: management + SPI + GPIO + I2C + UART + IPMI + MMIO | | sample_config/sample_0_channels.yaml | No I/O channels (management only) | | sample_config/sample_gpio14.yaml | Default: 1 GPIO channel (14 pins) | | sample_config/sample_gpio12_uart.yaml | 1 GPIO channel (12 pins) + 1 UART channel | | sample_config/sample_gpio12_i2c.yaml |...