AMD SB600 - page 64

AMD SB600 Register Reference Manual Proprietary Page 64

HcRhPortStatus - 32 bits - [MEM_Reg : 50h+4*(1:NDP)]

Field Name Bits Default HCD HC Description

PES 1 0b RW RW

(Read) PortEnableStatus

This bit indicates whether the port is enabled or

disabled. The Root Hub may clear this bit when an

overcurrent condition, disconnect event, switched-off

power, or operational bus error such as babble is

detected. This change also causes

PortEnabledStatusChange to be set. HCD sets this

bit by writing SetPortEnable and clears it by writing

ClearPortEnable. This bit cannot be set when

CurrentConnectStatus is cleared. This bit is also

set, if not already, at the completion of a port reset

when ResetStatusChange is set or port suspend

when SuspendStatusChange is set.

0 = Port is disabled

1 = Port is enabled

(Write) SetPortEnable

The HCD sets PortEnableStatus by writing a ‘1’.

Writing a ‘0’ has no effect. If CurrentConnectStatus

is cleared, this write does not set PortEnableStatus,

but instead sets ConnectStatusChange. This

informs the driver that it attempted to enable a

disconnected port.

PSS 2 0b RW RW

(Read) PortSuspendStatus

This bit indicates the port is suspended or in the

resume sequence. It is set by a SetSuspendState

write and cleared when PortSuspendStatusChange

is set at the end of the resume interval. This bit

cannot be set if CurrentConnectStatus is cleared.

This bit is also cleared when

PortResetStatusChange is set at the end of the port

reset or when the HC is placed in the USBRESUME

state. If an upstream resume is in progress, it should

propagate to the HC.

0 = Port is not suspended

1 = Port is suspended

(Write) SetPortSuspend

The HCD sets the PortSuspendStatus bit by writing

a ‘1’ to this bit. Writing a ‘0’ has no effect. If

CurrentConnectStatus is cleared, this write does

not set PortSuspendStatus; instead it sets

ConnectStatusChange. This informs the driver that

it attempted to suspend a disconnected port.

POCI 3 0b RW RW

(Read) PortOverCurrentIndicator

This bit is only valid when the Root Hub is configured

in such a way that overcurrent conditions are

reported on a per-port basis. If per-port overcurrent

reporting is not supported, this bit is set to 0. If

cleared, all power operations are normal for this port.

If set, an overcurrent condition exists on this port.

This bit always reflects the overcurrent input signal

0 = No overcurrent condition.

1 = Overcurrent condition detected.

(Write) ClearSuspendStatus

The HCD writes a ‘1’ to initiate a resume. Writing a ‘0’

has no effect. A resume is initiated only if

PortSuspendStatus is set.