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P5040/P5020 Reference Design Board User Guide, Rev. 0
Freescale Semiconductor
53
Programming Model
7.1.6
Clock Enable Register (PX_SERCLK)
This section outlines the clock enable register.
Figure 27. Clock Enable Register (PX_SERCLK)
Table 31. PX_RST Field Descriptions
Bits
1
Name
Description
0
ALL
2
Resets the entire system.
• 0 - Initiates a full system reset.
• 1 - Normal operation
1–3
—
Reserved
4
SXSLOT
Resets any board connected via the SGMII/XAUI riser card slot.
• 0 - SXSLOT_RST_B is asserted.
• 1 - SXSLOT_RST_B is deasserted.
5
PHY
Resets 10/100/1G Ethernet PHY.
• 0 - PHY_RST_B is asserted.
• 1 - PHY_RST_B is deasserted.
6
—
Reserved
7
GEN
Resets miscellaneous board features; see schematics and/or documentation.
• 0 - GEN_RST_B is asserted.
• 1 - GEN_RST_B is deasserted.
1
PX_RST register bits cannot reset independently.
2
PX_RST[ALL] only resets during a full system reset. Bits [1-7] must be cleared with software.
0
1
2
3
4
5
6
7
R
SERCLK_EN
SDREFCLK1_
EN
SDREFCLK2_
EN
SDREFCLK3_
EN
USBCLK_EN
SDREFCLK4_
EN
—
—
W
Reset
1
1
1
1
1
---
1
1
The Default depends on chip: For P5040 =’1’, otherwise ‘0’;
0
0
Offset
0x05
Table 32. PX_SERCLK Field Descriptions
Bits
Name
Description
0
SDREFCLK1_QA_EN
Enables/disables the SerDes Reference Clock to Bank 1 and Slot 1
• 0 - disabled
• 1 - enabled
1
SDREFCLK1_QB_EN
Enables/disables the SerDes Reference Clock to Aurora port and Slot 2
• 0 - disabled
• 1 - enabled
2
SDREFCLK2_QC_EN
Enables/disables the SerDes Reference Clock to Bank2 and XAUI PHY
• 0 - disabled
• 1 - enabled