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QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
OS Components & Operations
PCI Server User's Guide
API Reference
pci_device_rom_disable(), pci_device_rom_enable()
Enable or disable expansion ROM

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX Tool Suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
- Quickstart Guide
- System Architecture
  The System Architecture guide accompanies the QNX OS and is intended for both application developers and end-users.
- OS Components & Operations
  - Boot Optimization Guide
    The Boot Optimization Guide describes techniques you can use to reduce the time from your board's initial power on until you have a fully functional QNX system running on the board.
  - Building Embedded Systems
    The Building Embedded Systems guide is intended for developers who are developing or building BSPs for QNX OS embedded systems.
  - Customizing a BSP
    While QNX provides Board Support Packages (BSPs) for many common platforms and their individual variants, in some cases, you need a BSP for a board that QNX does not provide. If this is the case, you can modify a QNX BSP or develop your own.
  - Device Publishers Developer's Guide
  - High Availability Framework Developer's Guide
  - High-Performance Networking Stack (io-sock) User's Guide
    This guide contains instructions for implementing and using the QNX OS High-Performance Networking Stack and its manager, io-sock.
  - PCI Server User's Guide
    - PCI Server Overview
      The PCI server manages the hierarchy of PCI devices attached to a system.
    - PCI Hierarchy: Partitioning and Segmentation
      Partitioning and segmentation provide flexibility in using the PCI subsystem, and specifically the pci-server. It provides the ability to achieve:
    - Design Details
    - PCI multiplexer
    - API Reference
      - pci_bdf()
        Get the Bus/Device/Function associated with a device handle
      - pci_bdf_t
        Base type that encodes a Bus/Device/Function
      - pci_chassis_slot_bridge()
        Get the Bus/Device/Function of the bridge that's connected to the specified chassis and slot
      - pci_chassis_slot_device()
        Get the Bus/Device/Function of the device that resides in the specified chassis and slot
      - pci_device_attach()
        Attach a device
      - pci_device_cfg_cap_disable(), pci_device_cfg_cap_enable()
        Enable or disable a capability
      - pci_device_cfg_cap_isenabled()
        Check to see if a capability is enabled or disabled
      - pci_device_cfg_rd*()
        Read from the device-specific PCI configuration space registers
      - pci_device_cfg_wr*()
        Write to the device-specific PCI configuration space registers
      - pci_device_chassis_slot()
        Get the chassis and slot for a device
      - pci_device_detach()
        Detach a device
      - pci_device_find()
        Locate a device that matches the specified criteria
      - pci_device_find_capid()
        Get the index of a capability for a device
      - pci_device_find_capid_next()
        Get the index of the next occurrence of a specific capability of a device
      - pci_device_is_multi_func()
        Determine whether or not a device is a multifunction device
      - pci_device_map_as()
        Get the translation between CPU memory addresses and PCI addresses
      - pci_device_read_*()
        Read information from the common PCI configuration space registers
      - pci_device_read_ba()
        Get the base addresses of a device
      - pci_device_read_cap()
        Load a capability module
      - pci_device_read_capid()
        Get the ID of the nth capability that a device supports
      - pci_device_read_irq()
        Get the IRQs associated with a device
      - pci_device_reset()
        Reset a device
      - pci_device_rom_disable(), pci_device_rom_enable()
        Enable or disable expansion ROM
      - pci_device_write_cmd(), pci_device_write_status()
        Write a value in the device command or status register
      - pci_strerror()
        Get the description of an error code
    - Capability Modules and APIs
      This appendix describes some general-purpose capability modules and their APIs.
  - Performance Tuning User's Guide
  - QNX Filesystem for Safety User's Guide
  - SMMUMAN User's Guide
  - System Analysis Toolkit (SAT) User's Guide
  - Technotes
  - User's Guide
    The QNX OS User's Guide is intended for all users of a QNX OS system, from system administrators to end users.
- Graphics
- Programming
- System Security Guide
  The QNX System Security Guide is intended for both system integrators who are responsible for the security of a QNX OS system and developers who want to create a QNX OS resource manager free from vulnerabilities.
- Utilities & Libraries
- Migrating to QNX OS 8.0
QNX Software in the Cloud
QNX Software in the Cloud enables developers to use the QNX OS in the Amazon cloud environment.
QNX Toolkit for Visual Studio Code
This User's Guide describes the QNX^® Toolkit for Visual Studio Code. The guide introduces you to the QNX Toolkit by explaining the QNX development environment and how to build, run, and debug your QNX^® Operating System (OS) applications and systems.
QNX Hypervisor User's Guide
This User's Guide explains the QNX hypervisor architecture and provides instructions for installing and running a QNX Hypervisor system, changing system components and configuration, and using hypervisor features such as virtual devices (vdevs).
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation, explains how to obtain technical support, and provides some information about licensing.

pci_device_rom_disable(), pci_device_rom_enable()

QNX SDP8.0PCI Server User's GuideAPIConfiguration

Enable or disable expansion ROM

Synopsis:

#include <pci/pci.h>

pci_err_t pci_device_rom_disable( pci_devhdl_t hdl );

pci_err_t pci_device_rom_enable( pci_devhdl_t hdl );

Arguments:

hdl: The handle of the device, obtained by calling pci_device_attach().

Library:

libpci

Use the -l pci option to qcc to link against this library.

Description:

The pci_device_rom_enable() and pci_device_rom_disable() functions enable and disable a device's expansion ROM, respectively. It's your responsibility to enable the Memory Access bit in the command register.

Returns:

PCI_ERR_OK

Success.

PCI_ERR_ENODEV

The device identified by hdl doesn't exist. Note that this error can also be returned if a device that supports live removal is removed after a successful call to pci_device_find().

PCI_ERR_ENOTSUP

One of the following occurred:

The device identified by hdl isn't supported.
There are no expansion ROM entries for the device.

PCI_ERR_EINVAL

The hdl doesn't refer to a valid device that you attached to, or other parameters are otherwise invalid. This error can also be returned from the hardware-dependent module.

PCI_ERR_NOT_OWNER

You aren't the owner of the device; see pci_device_attach().

PCI_ERR_ASPACE_INVALID

The base addresses assigned to the device couldn't be translated into usable values for you. This is generally a hardware-dependent module error.

PCI_ERR_EIO

A device-specific error occurred.

Classification:


Safety:
Cancellation point	No
Signal handler	No
Thread	Yes

Page updated: August 11, 2025