7.4. Pause/PFC Flow Control Registers
Addr | Bit | Name | Description | Reset | Access |
---|---|---|---|---|---|
0x600 | 31:0 | TX Flow Control Revision ID | Specifies the revision ID, "25GEFCTx CSR". |
0x0916_2016 |
RO |
0x601 | 31:0 | TX Flow Control Scratch Pad | Scratch register for testing. | 0 | RW |
0x602 | 31:0 | TX Flow Control IP Core Variant 0 | Specifies first 4 characters of IP core variation identifier ASCII string, "25GE ". |
0x3235_4745 |
RO |
0x603 | 31:0 | TX Flow Control IP Core Variant 1 | Next 4 characters of IP core variation identifier ASCII string, "FCTx". | 0x4643_5478 | RO |
0x604 | 31:0 | TX Flow Control IP Core Variant 2 | Final 4 characters of IP core variation identifier ASCII string, "0CSR". The "0" is unprintable. |
0x0043_5352 | RO |
0x605 | (FCQN-1):0 |
TX Flow Control Enable |
Enables the IP core to generate XON and XOFF Pause/PFC flow control frames to the remote partner. The following encodings are defined:
You can change this field dynamically. |
1'b1 in each bit that corresponds to a queue |
RW |
31:FCQN |
Reserved | Reserved | 0 | RO | |
0x606 | (FCQN-1):0 |
TX Flow Control CSR XON/XOFF Request 1 One bit per queue |
XON/XOF flow control frame request bit 0. Interpretation depends on whether the IP core is in 1-bit FC request mode or in 2-bit FC request mode. This register affects a flow control queue only if the corresponding bit of the TX Flow Control Enable register has the value of 1. In 2-bit mode, in addition, this register is active for a specific flow control queue only if the corresponding bit in the TX 2-bit Flow Control Request Mode register field (bits [(FCQN-1):0] of the register at offset 0x641) specifies that the flow control logic accepts input from this register. The following encodings are defined for 1-bit mode. The IP core reads the 1-bit mode value in TX Flow Control CSR XON/XOFF Request 0.
The following encodings are defined for 2-bit mode. The IP core reads the 2-bit mode value in {TX Flow Control CSR XON/XOFF Request 1, TX Flow Control CSR XON/XOFF Request 1}.
You can modify the value of this field dynamically. |
0 | RW |
15:FCQN |
Reserved | Reserved | 0 | RO | |
(FCQN+15):16 |
TX Flow Control CSR XON/XOFF Request 1 1-bit per queue |
In conjunction with Flow Control XON/XOFF Request 0 specifies a 2-bit request for XON/XOFF flow control frame transmission. This bit is the upper bit of the 2-bit control field. You can change the value of this field dynamically. |
0 | RW | |
31:(FCQN+16) |
Reserved | Reserved | 0 | RO | |
0x607 | 31:0 | Reserved | Reserved | N/A | RO |
0x608 | 31:0 | Reserved | Reserved | N/A | RO |
0x609 | 31:0 | Reserved | Reserved | N/A | RO |
0x60A | 0 | TX Pause Enable 1-bit |
Determines whether receiving a valid Pause frame stops TX user data transmission. 1'b0: Transmission is not stopped 1'b1: Transmission stops You cannot change the value of this field dynamically. |
0 | RW |
31:1 | Reserved | Reserved | 0 | RO | |
0x60B | 31:0 | Reserved | Reserved | N/A | RO |
0x60C | 31:0 | Reserved | Reserved | N/A | RO |
0x60D | 31:0 | TX Flow Control Destination Address Lower | Specifies the 48-bit Destination Address of the flow control frame. Contains the 32 LSB of the address field. You cannot modify the value of this field dynamically. |
0xC2000001 | RW |
0x60E | 15:0 | TX Flow Control Destination Address Upper | Specifies the 48-bit Destination Address of flow control frame. Contains the 16 MSB of the address field. You cannot modify the value of this field dynamically. |
0x0180 | RW |
31:16 | Reserved | Reserved | 0 | RO | |
0x60F | 31:0 | TX Flow Control Source Address Lower | Specifies the 48-bit Source Address of flow control frame. Contains the 32 LSB of the address field. |
0xCBFC5ADD | RW |
0x610 | 15:0 | TX Flow Control Source Address Upper | Specifies the 48-bit Source Address of flow control frame. Contains the 16 MSB of the address field. You cannot modify the value of this field dynamically. |
0xE100 | RW |
31:16 | Reserved | Reserved | 0 | RO | |
0x620, 0x621, …, 0x620+(FCQN-1 ) |
15:0 | TX Flow Control Quanta 16-bit per queue |
Specifies the pause quanta of Pause/PFC flow control frames to be sent to remote partner. You cannot modify the value of this field dynamically. |
0xFFFF | RW |
31:16 | Reserved | Reserved | 0 | RO | |
0x628, 0x629, …, 0x628+(FCQN-1 ) | 15:0 | TX Flow Control Signal XOFF Request Hold Quanta 16-bit per queue |
Specifies the separation between 2 consecutive XOFF flow control frames. You cannot modify the value of this field dynamically. |
0xFFFF | RW |
31:16 | Reserved | Reserved | 0 | RO | |
0x640 | 0 | TX Flow Control Select 1-bit |
Specifies whether the TX hardware generates Pause or PFC frames. Affects only PFC Queue 0. Usage example: You can synthesize a single PFC queue and use it for both Pause and PFC purpose. 1'b0: Pause 1'b1: PFC You cannot modify the value of this field dynamically. |
1 | RW |
31:1 | Reserved. | Reserved. | 0 | RO | |
0x641 | (FCQN-1):0 | TX 2-bit Flow Control Request Mode 1-bit per queue |
Determines whether the TX Flow Control CSR XON/XOFF Request register or the pause_insert_tx0 and pause_insert_tx1 signals control XON/XOFF mode in 2-bit control mode. 1'b0: The pause_insert_tx0 and pause_insert_tx1 signals control requests 1'b1: The TX Flow Control CSR XON/XOFF Request register fields control requests You cannot modify the value of this field dynamically. |
0 | RW |
16 | TX Flow Control Request Mode 1 bit for all queues |
Determines whether the IP core is in TX flow control 1-bit mode or 2-bit mode. 1'b0: Use 1-bit mode to make TX flow control requests 1'b1: Use 2-bit mode to make TX flow control requests |
0 | RW | |
31:17 | Reserved | Reserved | 0 | RO |
Addr | Bit | Name | Description | Reset | Access |
---|---|---|---|---|---|
0x700 | 31:0 | RX Flow Control Revision ID | Provides the flow control revision, "25GEFCRx CSR". |
0x0916_2016 | RO |
0x701 | 31:0 | RX Flow Control Scratch Pad | Provides a register for debug. | 0 | RW |
0x702 | 31:0 | RX Flow Control IP Core Variant 0 | First 4 characters of IP core variation identifier ASCII string, "25GE". |
0x3235_4745 |
RO |
0x703 | 31:0 | RX Flow Control IP Core Variant 1 | Next 4 characters of IP core variation identifier ASCII string, "FCRx". | 0x4643_5278 | RO |
0x704 | 31:0 | RX Flow Control IP Core Variant 2 | Final 4 characters of IP core variation identifier ASCII string, "0CSR". The "0" is unprintable. | 0x0043_5352 | RO |
0x705 | (FCQN-1):0] | RX PFC Enable 1 bit per queue |
Determines whether receiving a valid PFC frame causes the PFC duration user interface to indicate a valid pause quanta duration to the user logic. 1'b0: Disable 1'b1: Enable You cannot modify the value of this field dynamically. |
1'b1 in each bit that corresponds to a queue | RW |
31:FCQN 8 | Reserved | Reserved | 0 | RO | |
0x706 | 31:0 | Reserved | Reserved | N/A | RO |
0x707 | 31:0 | RX Flow Control Destination Address Lower | Specifies the 48-bit Destination Address of the flow control frame. Contains the 32 LSB of the address field. You cannot modify the value of this field dynamically. |
0xC2000001 | RW |
0x708 | 15:0 | RX Flow Control Destination Address Upper | Specifies the 48-bit Destination Address of flow control frame. Contains the 16 MSB of the address field. You cannot modify the value of this field dynamically. |
0x0180 | RW |
31:16 | Reserved | Reserved | 0 | RO |