
4/29/2020
Godson 3A2000 / 3B2000 Processor User Manual
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Godson 3A2000 / 3B2000 Processor User Manual Part 1
10.5.29
PHY Configuration Register
Used to configure PHY related physical parameters. When the controller is used as two independent 8bit controllers, the high-order
The PHY and the lower PHY are independently controlled by two controllers; when the controller acts as a 16-bit controller, the upper bits
The configuration parameters of the lower PHY are controlled by the lower controller;
Offset: 0x17C
Reset value: 0x83308000
Name: PHY Configuration Register
Table 10-80 PHY Configuration Register
Bit field
Bit field name
Bit width reset value Visit description
31
Rx_ckpll_term
1
0x1
R / W PLL to RX end on-chip transmission line termination impedance
30
Tx_ckpll_term
1
0x0
R / W PLL to TX terminal on-chip transmission line termination impedance
29
Rx_clk_in_sel_
1
0x0
R / W
Clock PAD Clock selection for data PAD, HT1 mode
Under the formula, it is automatically selected as CLKPAD:
1'b0 external clock source
1'b1 PLL clock
28
Rx_ckdll_sell
1
0x0
R / W
Clock selection for locking DLL:
1'b0 PLL clock
1'b1 external clock source
27:26 Rx_ctle_bitc
2
0x0
R / W PAD EQD high frequency gain
25:24 Rx_ctle_bitr
2
0x3
R / W PAD EQD low frequency gain
23:22 Rx_ctle_bitlim
2
0x0
R / W PAD EQD compensation limit
twenty oneRx_en_ldo
1
0x1
R / W
LDO control
1'b0 LDO disabled
1'b1 LDO enable
20
Rx_en_by
1
0x1
R / W
BandGap control
1'b0 BandGap disabled
1'b1 BandGap enable
19: 17 Reserved
3
0x0
R
Keep
16:12 Tx_preenmp
5
0x08
R / W PAD pre-emphasis control signal
11: 0 Reserved
12
0x0
R
Keep
10.5.30
Link initialization debug register
Used to configure whether to use the CDR provided by the PHY during the link initialization process in HyperTransport 3.0 mode
The lock signal is used as the link CDR completion flag; if the lock signal is ignored, the controller needs to count and wait
By default, the default CDR is completed.
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Godson 3A2000 / 3B2000 Processor User Manual Part 1
Offset: 0x180
Reset value: 0x00000000
Name: Link initialization debug register
Table 10-81 Link Initialization Debug Register
Bit field
Bit field name
Bit width reset value Visit description
15
Cdr_ignore_enable 1
0x0
R / W
Whether to ignore the CRC lock during link initialization and pass the counter
Wait for the count to complete:
1'b0 wait for CDR lock
1'b1 Ignore the CDR lock signal and wait through the counter