EMPB(4) (amiga)

EMPB(4) | Device Drivers Manual (amiga) | EMPB(4)

# NAME

`empb` — ELBOX Mediator 1200 PCI bridge driver

# SYNOPSIS

`empb0 at zbus0`
`emmem0 at zbus0`
`empm0 at zbus0`
`pci* at empb0`
`options PCI_NETBSD_CONFIGURE`

# DESCRIPTION

The `empb` driver provides support for the PCI bus present on Mediator 1200 bridge for Amiga 1200.

# HARDWARE

The `empb` driver supports the following hardware:

ELBOX Mediator PCI 1200
ELBOX Mediator PCI 1200 LT2
ELBOX Mediator PCI 1200 LT4
ELBOX Mediator PCI 1200 SX
ELBOX Mediator PCI 1200 TX

# DIAGNOSTICS

empb: linear space mapping might not work
  The PCI card driver is trying map memory space with the `BUS_SPACE_MAP_LINEAR` flag. Due to the windowed design of Mediator, it is expected to fail miserably if normal memory space access methods (e.g., pointer dereference) are used instead of bus_space(9) methods.
empb%d: couldn't find memory space, check your WINDOW jumper
  PCI memory space access is disabled on a hardware level. The `empb` driver will work anyway, but only PCI I/O space will be accessible. To enable memory space set the WINDOW jumper to 4MB or 8MB.

# SEE ALSO

amiga/em4k(4), amiga/mppb(4), amiga/p5pb(4), pci(4)

# HISTORY

The `empb` device first appeared in NetBSD 7.0.

# AUTHORS

The `empb` driver was written by Radoslaw Kujawa <radoslaw.kujawa@gmail.com>. It was developed using information obtained through reverse engineering by Frank Wille and Radoslaw Kujawa. The authors have no access to official documentation (which is only available under NDA).

# CAVEATS

Mediator ZIV might work but is untested.

# BUGS

DMA to host memory is not supported. This is a hardware limitation. It is possible to implement DMA through bounce buffers in graphics card memory, but this needs further research.

February 17, 2017 | NetBSD 11.0