S5920Q Applied Micro Circuits Corporation, S5920Q Datasheet - Page 98

• Manufacturer Part Number: S5920Q
• Manufacturer: Applied Micro Circuits Corporation

Specifications of S5920Q

• Operating Temperature (min): 0C
• Operating Temperature Classification: Commercial
• Operating Temperature (max): 70C
• Package Type: PQFP
• Rad Hardened: No
• Lead Free Status / Rohs Status: Not Compliant

S5920 – PCI Product: Initialization
PCI BUS CONFIGURATION CYCLES
Cycles beginning with the assertion IDSEL and
FRAME# along with the two configuration command
states for C/BE[3:0] (configuration read or write)
access the selected device’s configuration space. Dur-
ing the address phase of the configuration cycle just
described, the values of AD0 and AD1 identify if the
Figure 42. PCI AD Bus Definition Type 0 Configuration Access
The configuration registers for the S5920 PCI control-
l e r c an o nl y b e a c c e s s e d u nd e r t he f ol l o w i ng
conditions:
Figure 8 describes the signal timing relationships for
configuration read cycles. Figure 9 describes configu-
ration write cycles.
AMCC Confidential and Proprietary
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transfer was successful or not. If XFER_FAIL is
asserted, this indicates that a transfer to the
nvRAM did not receive an ACKNOWLEDGE. The
read data in RCR(32:16) should not be consid-
ered valid. This flag remains set until the start of
the next read/write operation.
IDSEL high (PCI slot unique signal which iden-
tifies access to configuration registers) along
with FRAME# low.
Address bits A0 and A1 are 0 (Identifies a Type
0 configuration access).
Address bits A8, A9, and A10 are 0 (Function
number field of 0 supported).
Command bits, C/BE[3:0]# must identify a con-
figuration cycle command (101X).
31
RESERVED
00h
11
10
access is a Type 0 configuration cycle or a Type 1 con-
figuration cycle. Type 0 cycles have AD0 and AD1
equal to 0 and are used to access PCI bus agents.
Type 1 configuration cycles are intended only for
bridge devices and have AD0 as a 1 with AD1 as a 0
during the address phase.
The S5920 PCI device is a bus agent (not a bridge)
and responds only to a Type 0 configuration accesses.
Figure 7 depicts the state of the AD bus during the
address phase of a Type 0 configuration access. The
S5920 controller does not support the multiple function
numbers field (AD[10:8]) and only responds to the all-0
function number value.
Figure 43. Type 0 Configuration Read Cycles
FUNCTION
NUMBER
PCI CLK
FRAME#
AD[31:0]
C/BE[3:0]#
IRDY#
TRDY#
IDSEL
DEVSEL#
000
8
7
XXXXXXXX - INTERNAL REGISTER
REGISTER
NUMBER
0
12345
Revision 1.02 – April 12, 2007
ADD
1010
(DEVICE ID, ETC.)
2
ADDRESS
1
0
0
0
BYTE EN
TYPE 0
DATA
Data Book
DS1596
98