| .. _qemu_x86: |
| |
| X86 Emulation (QEMU) |
| #################### |
| |
| Overview |
| ******** |
| |
| The X86 QEMU board configuration is used to emulate the X86 architecture. |
| |
| .. figure:: qemu_x86.png |
| :width: 600px |
| :align: center |
| :alt: Qemu |
| |
| Qemu (Credit: qemu.org) |
| |
| This board configuration provides support for an x86 Minute IA (Lakemont) CPU |
| and the following devices: |
| |
| * HPET |
| * Advanced Programmable Interrupt Controller (APIC) |
| * NS16550 UART |
| |
| |
| Hardware |
| ******** |
| |
| Supported Features |
| ================== |
| |
| This configuration supports the following hardware features: |
| |
| +--------------+------------+-----------------------+ |
| | Interface | Controller | Driver/Component | |
| +==============+============+=======================+ |
| | HPET | on-chip | system clock | |
| +--------------+------------+-----------------------+ |
| | APIC | on-chip | interrupt controller | |
| +--------------+------------+-----------------------+ |
| | NS16550 | on-chip | serial port | |
| | UART | | | |
| +--------------+------------+-----------------------+ |
| |
| Devices |
| ======= |
| |
| HPET System Clock Support |
| ------------------------- |
| |
| The configuration uses an HPET clock frequency of 25 MHz. |
| |
| Serial Port |
| ----------- |
| |
| The board configuration uses a single serial communication channel that |
| uses the NS16550 serial driver operating in polling mode. To override, enable |
| the UART_INTERRUPT_DRIVEN Kconfig option, which allows the system to be |
| interrupt-driven. |
| |
| If SLIP networking is enabled (see below), an additional serial port will be |
| used for it. |
| |
| Known Problems or Limitations |
| ============================= |
| |
| The following platform features are unsupported: |
| |
| * Isolated Memory Regions |
| * Serial port in Direct Memory Access (DMA) mode |
| * Serial Peripheral Interface (SPI) flash |
| * General-Purpose Input/Output (GPIO) |
| * Inter-Integrated Circuit (I2C) |
| * Ethernet |
| * Supervisor Mode Execution Protection (SMEP) |
| |
| Programming and Debugging |
| ************************* |
| |
| Applications for the ``qemu_x86`` board configuration can be built and run in |
| the usual way for emulated boards (see :ref:`build_an_application` and |
| :ref:`application_run` for more details). |
| |
| Flashing |
| ======== |
| |
| While this board is emulated and you can't "flash" it, you can use this |
| configuration to run basic Zephyr applications and kernel tests in the QEMU |
| emulated environment. For example, with the :ref:`synchronization_sample`: |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/synchronization |
| :host-os: unix |
| :board: qemu_x86 |
| :goals: run |
| |
| This will build an image with the synchronization sample app, boot it using |
| QEMU, and display the following console output: |
| |
| .. code-block:: console |
| |
| ***** BOOTING ZEPHYR OS v1.8.99 - BUILD: Jun 27 2017 13:09:26 ***** |
| threadA: Hello World from x86! |
| threadB: Hello World from x86! |
| threadA: Hello World from x86! |
| threadB: Hello World from x86! |
| threadA: Hello World from x86! |
| threadB: Hello World from x86! |
| threadA: Hello World from x86! |
| threadB: Hello World from x86! |
| threadA: Hello World from x86! |
| threadB: Hello World from x86! |
| |
| Debugging |
| ========= |
| |
| Refer to the detailed overview about :ref:`application_debugging`. |
| |
| Networking |
| ========== |
| |
| The board supports SLIP networking over an emulated serial port |
| (``CONFIG_NET_SLIP_TAP=y``). The detailed setup is described in |
| :ref:`networking_with_qemu`. |
| |
| It is also possible to use the QEMU built-in Ethernet adapter to connect |
| to the host system. This is faster than using SLIP and is also the preferred |
| way. See :ref:`networking_with_eth_qemu` for details. |
