AMDISPLAY(4) | Device Drivers Manual (armv7) | AMDISPLAY(4)

# NAME

`amdisplay`, `nxphdmi` — Texas Instruments AM335x LCD display driver

# SYNOPSIS

`amdisplay* at simplebus0` |

`nxphdmi* at iic*` |

`wsdisplay* at amdisplay*` |

# DESCRIPTION

The `amdisplay` driver supports the LCD controller integrated in Texas Instruments' line of AM335x SoCs. The LCDC reads a framebuffer from memory via DMA and scans it out at the proper frequency to suit a display (along with the necessary hsync/vsync/etc. signals) to a PHY transmitter. The BeagleBone Black uses NXP/Freescale's TDA19988 HDMI transmitter, which is additionally supported by the `nxphdmi` driver.

# SEE ALSO

intro(4), wsdisplay(4), wsfb(4)

# HISTORY

The `amdisplay` driver first appeared in OpenBSD 6.2.

# AUTHORS

The `amdisplay` driver was written by Ian Sutton <ians@openbsd.org>. The `nxphdmi` driver was written by Oleksandr Tymoshenko <gonzo@freebsd.org> and later ported to OpenBSD.

# CAVEATS

On the BeagleBone Black, the LCDC and onboard eMMC NAND chip share the same set of pads such that only one can be wired and used at a time. To boot from or use the onboard storage, disable `amdisplay` via config(8) in the kernel.

A display must be attached at boot time, otherwise `amdisplay` will fail to configure.

Hotplugging is not supported.

Only 16-bit color depth is supported due to a silicon bug.

May 29, 2019 | Debian