Zynq UltraScale+ Devices Register Reference > Module Summary > PCIE_ATTRIB Module > ATTR_27 (PCIE_ATTRIB) Register

ATTR_27 (PCIE_ATTRIB) Register

ATTR_27 (PCIE_ATTRIB) Register Description

Register NameATTR_27
Relative Address0x000000006C
Absolute Address 0x00FD48006C (PCIE_ATTRIB)
Width32
TyperwNormal read/write
Reset Value0x00002138
DescriptionATTR_27

This register should only be written to during reset of the PCIe block

ATTR_27 (PCIE_ATTRIB) Register Bit-Field Summary

Field NameBitsTypeReset ValueDescription
attr_dev_cap_role_based_error13rwNormal read/write0x1Indicates that compliant error reporting is supported
attr_dev_cap_phantom_functions_support12:11rwNormal read/write0x0Phantom Function Support. Indicates number of Function Number that are reallocated to be Tag bits.
attr_dev_cap_max_payload_supported10:8rwNormal read/write0x1Specifies maximum payload supported.
Valid settings are: 0- 128 bytes, 1- 256 bytes, 2- 512 bytes, 3- 1024 bytes.
Transferred to the Device Capabilities register.
The values: 4-2048 bytes, 5- 4096 bytes are not supported
attr_dev_cap_function_level_reset_capable 7rwNormal read/write0x0Function Level Reset Capability. Indicates support for option FLR is allowed. Only applies to endpoints.
Reserved 6rwNormal read/write0x0reserved.
attr_dev_cap_endpoint_l1_latency 5:3rwNormal read/write0x7Endpoint L1 Acceptable Latency.
Records the latency that the endpoint can withstand on transitions from L1 state to L0 (if L1 state supported).
Valid settings are:
0h less than 1us, 1h 1 to 2us, 2h 2 to 4us, 3h 4 to 8us, 4h 8 to 16us, 5h 16 to 32us, 6h 32 to 64us, 7h more than 64us.
For Endpoints only.
Must be 0h for other devices.
attr_dev_cap_endpoint_l0s_latency 2:0rwNormal read/write0x0Endpoint L0s Acceptable Latency.
Records the latency the endpoint can withstand on transitions from L0s state to L0.
Valid settings are:
0h less than 64ns, 1h 64 to 128ns, 2h 128 to 256ns, 3h 256 to 512ns, 4h 512ns to 1us, 5h 1 to 2us, 6h 2 to 4 us, 7h more than 4us.
For Endpoints only.
Must be 0h for other devices.