OX16PCI954_05 Datasheet, PDF (29/73 Pages) Oxford Semiconductor – Integrated Quad UART and PCI interface

OXFORD SEMICONDUCTOR LTD.
disable all masks with the exception of the Ring Indicator,
so only a modem ring can wake up the computer.
When Function0 issues a wake up request, the
PME_Status (PMCSR[15]) will be set. This is a sticky bit
which will be cleared by writing a ‘1’ to it. While PME_En
(PMCSR[8]) in Function0 is set, PME_Status will assert the
PME# pin to inform the device driver that a power
management wake up event has occurred. After a wake up
event is signalled, the device driver is expected to return
the function to the D0 power-state.
6.6.2 Power Management of function 1
The power-down request for the Local Bus (Function1) is
application-dependent. The device driver can use any of
the multi-purpose I/O lines, MIO[12:3] to issue a power-
down request.
Function1 implements the PCI Power Management power-
states D0, D2 and D3. Whenever the device driver
changes the power-state to state D2 or D3, Function1
takes the following actions:-
• The external UART_Clk_Out pin is disabled
regardless of the programmed value in LCC[2].
OX16PCI954
• The Local Bus clock pin, LBCK, is disabled regardless
of the programmed value in LT2[30].
• The PCI interrupt for Function1 is disabled.
• Access to I/O or Memory BARs of Function1 is
disabled.
However, access to the configuration space is still enabled.
The device driver can optionally assert/de-assert any of its
selected (design dependant) MIO pins to switch off VCC,
disable other external clocks, or activate shut-down modes
to any external devices on the Local Bus.
Function1 can issue a wake up request by using the MIO2
pin. When LCC[7] is set, rising or falling edge of MIO2 will
cause Function1 to issue a wake up request by setting
PME_Status = (PMCSR[15]), if it is enabled by PMCSR[8]
of Function1. When LCC[7] is set, the MIO2 pin will remain
in input mode regardless of the value programmed in
MIC[5], However MIC[4] still controls the input sense.
PME_Status is a sticky bit which will be cleared by writing a
‘1’ to it. While PME_En (PMCSR[8]) bit in Function1 is set,
PME_Status will assert the PME# pin to inform the device
driver that a power management wake up event has
occurred. After a wake up event is signalled, the device
driver is expected to return the function to the D0 power-
state. Settings for wake up events are shown in Table 12.
LCC[6:5]
00
01
10
11
01
10
11
GIS[21]
X
0
0
0
1
1
1
Power-down
Filter Time
N/A
4s
129 s
518 s
4s
129 s
515 s
Operation
Function0 power-down interrupt is disabled. MIO1 can assert as
interrupt is GIS[21] is set.
Function0 power-down interrupt is disabled. GIS[5]
reflects the state of the internal power-down mode for
Polling operation. MIO1 interrupt is disabled.
Function0 power-down is enabled. GIS[5] reflects the state
of the internal power-down mode. MIO1 interrupt is
disabled.
Table 11: Function 0 (UARTs) Power down interrupt settings
LCC[7]
0
1
1
1
1
MIC[4]
X
0
0
1
1
MIO2 Rising
X
yes
no
X
X
MIO2 Falling
X
X
X
Yes
No
Function1 PME_Status
Remains unchanged
Gets set
Remains unchanged
Gets set
Remains unchanged
Table 12: Function 1 (Local Bus) Wake-up configuration
DS-0029 Jul 05
External—Free Release
Page 29