May 17, 2000 2

BIOS Considerations for USB 2.0

BIOS Considerations for USB 2.0

Saleem YamaniSaleem Yamani

Phoenix Technologies Ltd.Phoenix Technologies Ltd.

May 17, 2000 3

AgendaAgenda

BIOS CandidatesBIOS Candidates USB BIOS support for Keyboard and MouseUSB BIOS support for Keyboard and Mouse Booting from USBBooting from USB BIOS support for USB 2.0BIOS support for USB 2.0 Q & AQ & A

May 17, 2000 4

BIOS CandidatesBIOS Candidates

USB Keyboard supportUSB Keyboard support– Basic need of all environmentsBasic need of all environments

USB Mouse supportUSB Mouse support– For GUI and DOS game environmentsFor GUI and DOS game environments

USB Floppy, HardDisk, CD ROM supportUSB Floppy, HardDisk, CD ROM support– Potential future candidates - INT13H InterfacePotential future candidates - INT13H Interface

May 17, 2000 5

USB BIOS Requirementsfor Keyboard and MiceUSB BIOS Requirementsfor Keyboard and Mice

Design for Desktops, Portables and Server SystemsDesign for Desktops, Portables and Server Systems Build time support for Multiple Host ControllersBuild time support for Multiple Host Controllers Enumeration should handle all legalEnumeration should handle all legal

Bus topologiesBus topologies USB Devices must coexist with PS/2 DevicesUSB Devices must coexist with PS/2 Devices Must support multiple USB Keyboards &Must support multiple USB Keyboards &

USB MiceUSB Mice

May 17, 2000 6

USB BIOS Requirementsfor Keyboard and MiceUSB BIOS Requirementsfor Keyboard and Mice

Each USB Keyboard has its own Typematic RateEach USB Keyboard has its own Typematic Rate Hot Attach/Detach must be supportedHot Attach/Detach must be supported Must be able to transition to the USB Aware O/SMust be able to transition to the USB Aware O/S USB support performance must be usableUSB support performance must be usable

– Must not notice the difference between PS/2 & USBMust not notice the difference between PS/2 & USB USB must not degrade System performanceUSB must not degrade System performance

– When USB Devices are idleWhen USB Devices are idle– When “PS/2 Devices only” mode is selectedWhen “PS/2 Devices only” mode is selected

May 17, 2000 7

Device Emulation OverviewDevice Emulation Overview

Both the PS/2 Mouse & PS/2 Keyboard are Both the PS/2 Mouse & PS/2 Keyboard are emulated along with the Keyboard Controlleremulated along with the Keyboard Controller

An SMI is generated on accesses to the KBCAn SMI is generated on accesses to the KBC An SMI is generated by the Host ControllerAn SMI is generated by the Host Controller

on a “Transfer Completion” eventon a “Transfer Completion” event USB Data is converted & sent to the SystemUSB Data is converted & sent to the System

– UHCI: Echoed through the Keyboard ControllerUHCI: Echoed through the Keyboard Controller– OHCI: Placed in the Legacy Registers.OHCI: Placed in the Legacy Registers.

May 17, 2000 8

Device Emulation OverviewDevice Emulation Overview

Block diagrams of UHCI & OHCI SMI TrappingBlock diagrams of UHCI & OHCI SMI Trapping– UHCI: KBC Status and IRQ’s come from the KBCUHCI: KBC Status and IRQ’s come from the KBC– OHCI: KBC Status and IRQ’s come from the Host OHCI: KBC Status and IRQ’s come from the Host

Controller’s Legacy hardwareController’s Legacy hardware

wr60wr64rd60rd64

IRQ’s

SMISMITrapTrap

KbcKbc

Universal HCI

SMISMITrapTrap KbcKbcLatchLatch

Open HCI

wr60wr64rd60rd64

IRQ’s

May 17, 2000 9

USB BIOS & O/S SupportUSB BIOS & O/S Support

BIOS InitializationBIOS Initialization

USB InitializationUSB Initialization

BIOS SurrendersBIOS Surrendersto the O/Sto the O/S

BIOS LegacyBIOS LegacySupport StaysSupport Stays

IntactIntact

USB AwareUSB AwareOperating SystemOperating System

Non-USB AwareNon-USB AwareOperating SystemOperating SystemNon-USB AwareNon-USB Aware

Operating SystemOperating System

BIOS TransitionBIOS Transition

BIOS

OSOS

May 17, 2000 10

SMI PerformanceSMI Performance

10 SMI’s per Keystroke (5 Make + 5 Break)10 SMI’s per Keystroke (5 Make + 5 Break)– USB Device Transfer Completion (hcTransfer)USB Device Transfer Completion (hcTransfer)– INT09h’s Disable of the Keyboard Interface (ADh)INT09h’s Disable of the Keyboard Interface (ADh)– INT09h’s Read of Port 60hINT09h’s Read of Port 60h– INT09h’s Re-Enable of the Keyboard Interface (AEh)INT09h’s Re-Enable of the Keyboard Interface (AEh)– Persistence Callback (UHCI only)Persistence Callback (UHCI only)

On OHCI the Rd P60h & the Persistence are the same SMIOn OHCI the Rd P60h & the Persistence are the same SMI

Arrow Keys w/NumLk 34 SMI’s per KeystrokeArrow Keys w/NumLk 34 SMI’s per Keystroke

May 17, 2000 11

Legacy-Free KeyboardLegacy-Free Keyboard

Keyboard and Mouse still available during POSTKeyboard and Mouse still available during POST INT15H (C2H), INT16H CompatibleINT15H (C2H), INT16H Compatible Legacy-Free Keyboard Feature set sameLegacy-Free Keyboard Feature set same

as currentas current Keyboard Controller hardware issuesKeyboard Controller hardware issues

finally addressedfinally addressed

May 17, 2000 12

Legacy-Free KeyboardLegacy-Free Keyboard

GateA20 Confusion and Problems are eliminatedGateA20 Confusion and Problems are eliminated USB SMI Emulation is no longer requiredUSB SMI Emulation is no longer required

– USB uses a standard IRQ insteadUSB uses a standard IRQ instead IRQ1 and IRQ12 are releasedIRQ1 and IRQ12 are released Keyboard Module simplifiedKeyboard Module simplified

ContinuedContinued

May 17, 2000 13

Current DesktopCurrent DesktopDesktop & Server Block DiagramDesktop & Server Block Diagram

ISA PCI

IRQ1IRQ12

SMI

Desktop

PS/2 KeyboardPS/2 Keyboard USB KeyboardUSB Keyboard

KeyboardKeyboardControllerController

USB HostUSB HostControllerController

USB

May 17, 2000 14

Legacy-Free DesktopLegacy-Free DesktopDesktop & Server Block DiagramDesktop & Server Block Diagram

PCI

EOT(PCI IRQ)

Desktop

USB KeyboardUSB Keyboard

USB HostUSB HostControllerController

USB

May 17, 2000 15

Replacing the FloppyReplacing the Floppy

HostHost Hub

DeviceDevice

DeviceDevice

DeviceDevice

DeviceDevice

DeviceDevice

May 17, 2000 16

Boot From USB?Boot From USB?

Any device which must function before the OSAny device which must function before the OSis launched is a boot deviceis launched is a boot device– Devices required for BIOS utilitiesDevices required for BIOS utilities

Keyboard, MouseKeyboard, Mouse– Initial Program Load (IPL) devicesInitial Program Load (IPL) devices

Floppy, Tape, CD, LS-120, Zip, etc.Floppy, Tape, CD, LS-120, Zip, etc.

May 17, 2000 17

Unique USB ChallengesUnique USB Challenges

Hot-plug BusHot-plug Bus– DOS does not allow hot-pluggingDOS does not allow hot-plugging– BIOS is not structured for hot-pluggingBIOS is not structured for hot-plugging

Master/Slave BusMaster/Slave Bus– CPU intensive, devices do not speak unlessCPU intensive, devices do not speak unless

they are spoken toothey are spoken too– Requires a hand-offRequires a hand-off

May 17, 2000 18

What Constitutes a Mass Storage Device?What Constitutes a Mass Storage Device?

The USB Mass Storage document definesThe USB Mass Storage document definesa SCSI to USB bridgea SCSI to USB bridge– This is not limited to rotating media, it canThis is not limited to rotating media, it can

include any ATAPI or SCSI deviceinclude any ATAPI or SCSI device Any SCSI deviceAny SCSI device Any ATAPI deviceAny ATAPI device Two transport mechanismsTwo transport mechanisms

– Control-Bulk-Interrupt (CBI)Control-Bulk-Interrupt (CBI)– Bulk-Only Transport (BOT)Bulk-Only Transport (BOT)– Can be found at WWW.USB.ORGCan be found at WWW.USB.ORG

May 17, 2000 19

Why Serial NumberWhy Serial Number

Allows for a change in topologyAllows for a change in topology– The user can hot-plug USB devicesThe user can hot-plug USB devices– This causes a bus re-enumerationThis causes a bus re-enumeration– USB physical addresses can changeUSB physical addresses can change– Serial number keeps A: on the expectedSerial number keeps A: on the expected

device during a hot-plugdevice during a hot-plug Allows for interchange of devicesAllows for interchange of devices

– When devices are re-inserted they canWhen devices are re-inserted they canmaintain their original drive lettersmaintain their original drive letters

May 17, 2000 20

Requesting Serial NumberRequesting Serial Number

Serial Number is required for devices that follow Serial Number is required for devices that follow the BOT specificationthe BOT specification

Serial Number is optional for devices that follow Serial Number is optional for devices that follow the CBI specificationthe CBI specification– Mainly USB 1.44MB floppy drivesMainly USB 1.44MB floppy drives

Require Serial Number SupportRequire Serial Number SupportFor Your USB Floppy DriveFor Your USB Floppy Drive

Require Serial Number SupportRequire Serial Number SupportFor Your USB Floppy DriveFor Your USB Floppy Drive

May 17, 2000 21

Appropriate MSD DevicesAppropriate MSD Devices

Devices with minor speed considerationsDevices with minor speed considerations– Large FloppyLarge Floppy– Slow TapeSlow Tape– Any Mass Storage device which is interfacedAny Mass Storage device which is interfaced

via parallel port, todayvia parallel port, today USB 2.0 will bring many new devices to USBUSB 2.0 will bring many new devices to USB

– Hard Drives, CD-ROM drives, etc.Hard Drives, CD-ROM drives, etc.

May 17, 2000 22

Special Use DevicesSpecial Use Devices

Laptops are driving these devicesLaptops are driving these devices Likely storage devices which canLikely storage devices which can

consume the entire busconsume the entire bus– CDCD– Solid StateSolid State– SCSI to USB bridgeSCSI to USB bridge– TapeTape

USB 2.0 changes these from special use to normal USB 2.0 changes these from special use to normal use devices for laptops, desktops, work stations, use devices for laptops, desktops, work stations, and serversand servers

May 17, 2000 23

USB Boot In ConclusionUSB Boot In Conclusion

Phoenix is currently offering support forPhoenix is currently offering support for– FloppyFloppy– ZipZip

In processIn process– CD-ROMCD-ROM

Devices to follow as neededDevices to follow as needed

May 17, 2000 24

BIOS Support for USB 2.0BIOS Support for USB 2.0

Initial Host Controllers will be hybrid typeInitial Host Controllers will be hybrid type– ““Classic” core handles USB 1.0/1.1 devicesClassic” core handles USB 1.0/1.1 devices– ““High speed” core handles USB 2.0 devicesHigh speed” core handles USB 2.0 devices– Router routes traffic to either “classic” orRouter routes traffic to either “classic” or

“high speed” core“high speed” core Greater system resources to supportGreater system resources to support

– ““Classic” Host controllerClassic” Host controller– ““High speed” Host Controller High speed” Host Controller

May 17, 2000 25

BIOS Support forHybrid ControllerBIOS Support forHybrid Controller

BIOS Can Support HS/FS device at FSBIOS Can Support HS/FS device at FS– Using Classic portionUsing Classic portion– No new code requiredNo new code required– Performance degradedPerformance degraded

BIOS Can Support FS/LS device at FS/LSBIOS Can Support FS/LS device at FS/LS– Using Classic portionUsing Classic portion– No new code requiredNo new code required

May 17, 2000 26

BIOS Support forHS ControllerBIOS Support forHS Controller

New code to support New code to support – HS devicesHS devices– FS/LS devices using split transactionFS/LS devices using split transaction

May 17, 2000 27

USB 2.0USB 2.0Host ChipHost ChipUSB 2.0USB 2.0Host ChipHost Chip

USB 2.0 Host ArchitectureEarly Discrete Host ChipUSB 2.0 Host ArchitectureEarly Discrete Host Chip

RouterRouterRouterRouter

USB 1.1USB 1.1HostHost

USB 1.1USB 1.1HostHost

USB 1.1 USB 1.1 signalssignalsUSB 1.1 USB 1.1 signalssignals

USB 2.0USB 2.0HostHost

USB 2.0USB 2.0HostHost

USB 2.0 USB 2.0 signalssignalsUSB 2.0 USB 2.0 signalssignals

USB 1.1 signals

USB 2.0 signals

May 17, 2000 28

USB 2.0USB 2.0Host ChipHost ChipUSB 2.0USB 2.0Host ChipHost Chip

USB 2.0 Host ArchitectureFinal Host DesignUSB 2.0 Host ArchitectureFinal Host Design

USB 2.0 HubUSB 2.0 HubUSB 2.0 HubUSB 2.0 Hub

USB 1.1 USB 1.1 signalssignals

USB 2.0USB 2.0HostHost

USB 2.0USB 2.0HostHost

USB 2.0 USB 2.0 signalssignals

USB 2.0 USB 2.0 signalssignals

May 17, 2000 29

USB HS/FS/LS CompatibilityUSB HS/FS/LS Compatibility

USB 1.1USB 1.1USB 2.0USB 2.0

\65\6 0m

m

USB 1.1USB 1.1

Hub

USB 2.0USB 2.0

Hub

May 17, 2000 30

USB HS/FS/LS CompatibilityUSB HS/FS/LS Compatibility

USB2.0 DeviceUSB2.0 Device

USB 1.0/1.1 USB 1.0/1.1 DeviceDevice

USB 1.0/1.1 USB 1.0/1.1 HostHost USB2.0 HostUSB2.0 Host

Device connects and Device connects and functions in “classic functions in “classic

mode”mode”

Device connects Device connects and functions in and functions in “classic mode”“classic mode”

Device connects and Device connects and functions in “high functions in “high

speed mode”speed mode”

Device connects in Device connects in “classic mode” and if “classic mode” and if capable, functions in capable, functions in

“classic mode”“classic mode”