PXN20RM Datasheet, PDF (433/1376 Pages) Freescale Semiconductor, Inc – PXN20 Microcontroller

AMBA Crossbar Switch (AXBS)
Address: AXBS_BASE + 0x0010 (XBAR_SGPCR0) AXBS_BASE + 0x0310 (XBAR_SGPCR3)
AXBS_BASE + 0x0110 (XBAR_SGPCR1) AXBS_BASE + 0x0610 (XBAR_SGPCR6)
AXBS_BASE + 0x0210 (XBAR_SGPCR2) AXBS_BASE + 0x0710 (XBAR_SGPCR7) Access: Supervisor read/write
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RO¹
W
Reset 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
R0
0
0
0
0
0
W
ARB
0
0
0
PCTL
PARK
Reset 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1 _{After this bit is set, only a hardware reset clears it.}
Figure 16-3. Slave General-Purpose Control Registers (XBAR_SGPCRn)
Table 16-5. XBAR_SGPCRn Field Descriptions
Field
RO
ARB
PCTL
PARK
Description
Read only. Used to force all of a slave port’s registers to be read-only. After written to 1, it can only be cleared by
hardware reset.
0 All this slave port’s registers can be written.
1 All this slave port’s registers are read-only and cannot be written (attempted writes have no effect and result
in an error response).
Arbitration mode. Used to select the arbitration policy for the slave port. This field is initialized by hardware reset.
00 Fixed priority using MPR
01 Round-robin priority
10 Invalid value
11 Invalid value
Parking control. Used to select the parking algorithm used by the slave port. This field is initialized by hardware
reset.
00 When no master is making a request, the arbiter parks the slave port on the master port defined by the PARK
control field.
01 POL—Park on last. When no master is making a request, the arbiter parks the slave port on the last master
to own the slave port.
10 LPP—Low-power park. When no master is making a request, the arbiter parks the slave port on no master
and drives all slave port outputs to a safe state.
11 Invalid value
Park. Used to determine which master port this slave port parks on when no masters are actively making
requests. PCTL must be set to 00.
000 Park on master port 0
001 Park on master port 1
010 Park on master port 2
011 Park on master port 3
100 Invalid value
101 Invalid value
110 Park on master port 6
111 Park on master port 7
Freescale Semiconductor
PXN20 Microcontroller Reference Manual, Rev. 1
16-7