Nuvoton iBMC boards (``*-bmc``, ``npcm750-evb``, ``quanta-gsj``)
================================================================

The `Nuvoton iBMC`_ chips (NPCM7xx) are a family of ARM-based SoCs that are
designed to be used as Baseboard Management Controllers (BMCs) in various
servers. They all feature one or two ARM Cortex-A9 CPU cores, as well as an
assortment of peripherals targeted for either Enterprise or Data Center /
Hyperscale applications. The former is a superset of the latter, so NPCM750 has
all the peripherals of NPCM730 and more.

.. _Nuvoton iBMC: https://www.nuvoton.com/products/cloud-computing/ibmc/

The NPCM750 SoC has two Cortex-A9 cores and is targeted for the Enterprise
segment. The following machines are based on this chip :

- ``npcm750-evb``       Nuvoton NPCM750 Evaluation board

The NPCM730 SoC has two Cortex-A9 cores and is targeted for Data Center and
Hyperscale applications. The following machines are based on this chip :

- ``quanta-gbs-bmc``    Quanta GBS server BMC
- ``quanta-gsj``        Quanta GSJ server BMC
- ``kudo-bmc``          Fii USA Kudo server BMC

There are also two more SoCs, NPCM710 and NPCM705, which are single-core
variants of NPCM750 and NPCM730, respectively. These are currently not
supported by QEMU.

Supported devices
-----------------

 * SMP (Dual Core Cortex-A9)
 * Cortex-A9MPCore built-in peripherals: SCU, GIC, Global Timer, Private Timer
   and Watchdog.
 * SRAM, ROM and DRAM mappings
 * System Global Control Registers (GCR)
 * Clock and reset controller (CLK)
 * Timer controller (TIM)
 * Serial ports (16550-based)
 * DDR4 memory controller (dummy interface indicating memory training is done)
 * OTP controllers (no protection features)
 * Flash Interface Unit (FIU; no protection features)
 * Random Number Generator (RNG)
 * USB host (USBH)
 * GPIO controller
 * Analog to Digital Converter (ADC)
 * Pulse Width Modulation (PWM)
 * SMBus controller (SMBF)
 * Ethernet controller (EMC)
 * Tachometer

Missing devices
---------------

 * LPC/eSPI host-to-BMC interface, including

   * Keyboard and mouse controller interface (KBCI)
   * Keyboard Controller Style (KCS) channels
   * BIOS POST code FIFO
   * System Wake-up Control (SWC)
   * Shared memory (SHM)
   * eSPI slave interface

 * Ethernet controller (GMAC)
 * USB device (USBD)
 * Peripheral SPI controller (PSPI)
 * SD/MMC host
 * PECI interface
 * PCI and PCIe root complex and bridges
 * VDM and MCTP support
 * Serial I/O expansion
 * LPC/eSPI host
 * Coprocessor
 * Graphics
 * Video capture
 * Encoding compression engine
 * Security features

Boot options
------------

The Nuvoton machines can boot from an OpenBMC firmware image, or directly into
a kernel using the ``-kernel`` option. OpenBMC images for ``quanta-gsj`` and
possibly others can be downloaded from the OpenPOWER jenkins :

   https://openpower.xyz/

The firmware image should be attached as an MTD drive. Example :

.. code-block:: bash

  $ qemu-system-arm -machine quanta-gsj -nographic \
      -drive file=image-bmc,if=mtd,bus=0,unit=0,format=raw

The default root password for test images is usually ``0penBmc``.