BT(4)

📦 version 12.2, in debian bookworm, debian trixie, ubuntu jammy, ubuntu noble, ubuntu questing, ubuntu resolute, ubuntu stonking

👑 BT(4) — Buslogic/Mylex MultiMaster SCSI host adapter driver 💅

okay so this is a page from the Kernel Interfaces Manual, section 4, and it's all about the bt driver. bestie, we're gonna get you fluent in MultiMaster lore. let's go ✨

🌸 NAME 🌸

bt — the Buslogic/Mylex MultiMaster SCSI host adapter driver. that's the whole vibe. it drives your SCSI host adapter, it's giving main character energy, periodt.

🎀 SYNOPSIS 🎀

so if you wanna compile this driver into the kernel, you literally place these lines in your kernel configuration file:

device isa
device scbus
device bt

and then in /boot/device.hints you drop these:

hint.bt.0.at="isa"
hint.bt.0.port="0x330"

that's it. that's the recipe. 🫶

💀 DEPRECATION NOTICE 💀

NOT me delivering bad news but… this driver is scheduled for removal prior to the release of FreeBSD 13.0. so like, enjoy it while it lasts. it's giving limited edition. 😭

✨ DESCRIPTION ✨

so here's the tea: this driver provides access to the SCSI bus connected to a Buslogic/Mylex MultiMaster or compatible controller. and the family tree is extensive, okay? look at her go 🌈

MultiMaster "W" Series Host Adapters:

Adapter      Bus     Commands     Description
BT-948       PCI     192          Ultra SCSI-3
BT-958       PCI     192          Wide Ultra SCSI-3
BT-958D      PCI     192          Wide Differential Ultra SCSI-3

MultiMaster "C" Series Host Adapters:

Adapter      Bus     Commands     Description
BT-946C      PCI     100          Fast SCSI-2
BT-956C      PCI     100          Wide Fast SCSI-2
BT-956CD     PCI     100          Wide Differential Fast SCSI-2
BT-445C      VLB     100          Fast SCSI-2
BT-545C      ISA     50           Fast SCSI-2
BT-540CF     ISA     50           Fast SCSI-2

MultiMaster "S" Series Host Adapters:

Adapter      Bus     Commands     Description
BT-445S      VLB     30           Fast SCSI-2
BT-545S      ISA     30           Fast SCSI-2
BT-542D      ISA     30           Differential Fast SCSI-2
BT-542B      ISA     30           SCSI-2 (542B revision H)

MultiMaster "A" Series Host Adapters:

Adapter      Bus     Commands     Description
BT-542B      ISA     30           SCSI-2 (542B revisions A - G)

now, tagged queueing is supported on:

  • 'W' series adapters
  • 'C' series adapters with firmware of rev 4.42 and higher
  • 'S' series adapters with firmware of rev 3.35 and higher
⚠️ heads up bestie, this part is important: boards with certain firmware revisions may lock up under heavy load to certain devices, especially if tagged queueing is used. if you encounter a problem with your adapter, contact Mylex technical support and make sure you have the latest firmware for your controller. no cap, do not skip this step. 🙈

🦋 HARDWARE 🦋

the bt driver supports the following BusLogic MultiMaster "W", "C", "S", and "A" series and compatible SCSI host adapters:

  • BusLogic BT-445C
  • BusLogic BT-445S
  • BusLogic BT-540CF
  • BusLogic BT-542B
  • BusLogic BT-542B
  • BusLogic BT-542D
  • BusLogic BT-545C
  • BusLogic BT-545S
  • BusLogic/BusTek BT-640
  • BusLogic BT-946C
  • BusLogic BT-948
  • BusLogic BT-956C
  • BusLogic BT-956CD
  • BusLogic BT-958
  • BusLogic BT-958D
  • Storage Dimensions SDC3211B / SDC3211F

(yes, BT-542B is listed twice. that's not me being messy, that's literally what the page says. iconic behaviour honestly. 💅)

🔥 SEE ALSO 🔥

go read those next, iykyk 👑

🌈 HISTORY 🌈

the bt driver first appeared in the 386BSD patch kit. a true vintage queen. a legend from day one. ⭐

🫶 AUTHORS 🫶

  • Julian Elischer wrote a driver for the Multimaster cards that appeared in the 386BSD patch kit.
  • The driver was rewritten by Justin T. Gibbs to take advantage of new board features and work with the CAM SCSI framework in FreeBSD 3.0.

and a huge special thanks to Leonard N. Zubkoff for writing such a complete and well documented Mylex/BusLogic MultiMaster driver for Linux. fr fr, support in this driver for the wide range of MultiMaster controllers and firmware revisions — with their otherwise undocumented quirks — would not have been possible without his efforts. absolute legend. 🎀

and that's the whole page, bestie 💖 this one came out of the Debian crew, dated August 18, 2020, and it lives at BT(4). slay, you're now certified in MultiMaster. 🦋✨

📦 where this page comes from