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Crossbar Switch (XBS)
Freescale Semiconductor
15-5
NOTE
The possible values for the XBS_PRS
n
fields depend on the number of
masters available on the device. Because the device contains seven masters,
valid values are 000 to 110. Unpredictable results occur when using the
reserved setting 111.
15.4.2
XBS Control Registers (XBS_CRS
n
)
The XBS control registers (XBS_CRS
n
) control several features of each slave port and must be accessed
using 32-bit accesses. After XBS_CRS
n
[RO] is set, the XBS_CRS
n
can only be read; attempts to write to
it have no effect and result in an error response.
Table 15-3. XBS_PRS
n
Field Descriptions
Field
Description
31
Reserved, must be cleared.
30–28
M7
Master 7 (Serial Boot) priority. Sets the arbitration priority for this port on the associated slave port.
000 This master has level 1 (highest) priority when accessing the slave port.
001 This master has level 2 priority when accessing the slave port.
010 This master has level 3 priority when accessing the slave port.
011 This master has level 4 priority when accessing the slave port.
100 This master has level 5 priority when accessing the slave port.
101 This master has level 6 priority when accessing the slave port.
110 This master has level 7 (lowest) priority when accessing the slave port.
Else Reserved
27
Reserved, must be cleared.
26–24
M6
Master 6 (USB OTG) priority. See M7 description.
23
Reserved, must be cleared.
22–20
M5
Master 5 (PCI controller) priority. See M7 description.
19–15
Reserved, must be cleared.
14–12
M3
Master 3 (FEC1) priority. See M7 description.
11
Reserved, must be cleared.
10–8
M2
Master 2 (FEC0) priority. See M7 description.
7
Reserved, must be cleared.
6–4
M1
Master 1 (eDMA) priority. See M7 description.
3
Reserved, must be cleared.
2–0
M0
Master 0 (ColdFire core) priority. See M7 description.
Summary of Contents for MCF54455
Page 33: ...xxviii Freescale Semiconductor ...
Page 67: ...Freescale Semiconductor 1 ...
Page 125: ...Freescale Semiconductor 1 ...
Page 145: ...Enhanced Multiply Accumulate Unit EMAC 5 21 Freescale Semiconductor ...
Page 173: ...Cache 6 28 Freescale Semiconductor ...
Page 179: ...Static RAM SRAM 7 6 Freescale Semiconductor ...
Page 207: ...Power Management 9 16 Freescale Semiconductor ...
Page 323: ...Reset Controller Module 13 8 Freescale Semiconductor ...
Page 389: ...Pin Multiplexing and Control 16 44 Freescale Semiconductor ...
Page 575: ...PCI Bus Controller 22 58 Freescale Semiconductor ...
Page 600: ...Advanced Technology Attachment ATA Freescale Semiconductor 23 25 ...
Page 601: ...Freescale Semiconductor 1 ...
Page 842: ...I2 C Interface Freescale Semiconductor 33 16 ...
Page 843: ...Freescale Semiconductor 1 ...
Page 921: ...Revision History A 6 Freescale Semiconductor ...