Intel® Core™ Ultra Series 3 Processors I/O Registers
| ID | Date | Version | Classification |
|---|---|---|---|
| 872352 | 04/14/2026 | 001 | Public |
Device Control 1 (GIO_DEV) – Offset 48
Device Control register (Offset 0x48 )
| Bit Range | Default | Access | Field Name and Description |
|---|---|---|---|
| 31:22 | 0h | RO | Reserved |
| 21 | 0h | RO | TRANS PEND (TRANS_PEND) indicates that a device has Non-Posted Requests which have not been completed |
| 20 | 1h | RO | Auxiliary P Detect (AUX_P_DET) device that requires AUX power reports this bit (asynch signal) |
| 19 | 0h | RW/1C | UNSOP Request Detect (UNSOP_REQ_DET) indicates that the device received Unsupported Request |
| 18 | 0h | RW/1C | FAT Error Detect (FAT_ERR_DET) indicates status of fatal errors detected |
| 17 | 0h | RW/1C | NFAT ER Detect (NFAT_ER_DET) indicates status of non-fatal errors detected |
| 16 | 0h | RW/1C | COR Error Detect (COR_ERR_DET) indicates status of correctable errors detected |
| 15 | 0h | RO | INIT FNC LV RS (INIT_FNC_LV_RS) Initiate Function Level Reset - A write of 1b initiates Function (init FLR) this bit is RW after gf_cfg_dev_cap_flr_sup is set from OTP |
| 14:12 | 0h | RO | Maximum RDRQ SIZE (MAX_RDRQ_SIZE) sets the maximum Read Request size |
| 11 | 1h | RW | Enable NO SNOOP (EN_NO_SNOOP) Enable No Snoop (if set device is permitted to set No Snoop bit) |
| 10 | 1h | RW | Auxiliary PM Enable (AUX_PM_EN) Auxiliary (AUX) Power PM Enable. sticky value. |
| 9 | 0h | RO | Reserved |
| 8 | 0h | RW | External TAG Enable (EXT_TAG_EN) Extend tag field en RW. new in 2023 |
| 7:5 | 0h | RW | Maximum PAY SIZE (MAX_PAY_SIZE) sets maximum TLP payload size for the device functions |
| 4 | 1h | RW | Enable REL ORD (EN_REL_ORD) when set device permitted to set the Relaxed Ordering bit |
| 3 | 0h | RW | UNSOP Request REP (UNSOP_REQ_REP) enables reporting of Unsupported Request when set |
| 2 | 0h | RW | FAT Error REP (FAT_ERR_REP) controls reporting of fatal errors |
| 1 | 0h | RW | NFAT ER REP (NFAT_ER_REP) controls reporting of non-fatal errors |
| 0 | 0h | RW | COR Error REP (COR_ERR_REP) controls reporting of correctable errors |