Intel® 800 Series Chipset Family Platform Controller Hub (PCH), Volume 2
ID | Date | Version | Classification |
---|---|---|---|
834576 | 10/10/2024 | 001 | Public |
Outbound DoorbellISH To HOST (ISH2HOST_DOORBELL_HOST) – Offset 54
Outbound doorbell register for the ISH to interrupt HOST. Setting bit 31 of this register causes the Host to receive a IRQn interrupt. Data 30:0 is 31bits message payload used for backward compatibility. Software can use either this 31bit message payload or 256bit payload registers. The ISH will set bit 31 of this reg to ring the doorbell after it has completed programming the message to Host. When the Host reads the message code from this register it should write back to this register and clear the BUSY bit.
Bit Range | Default | Access | Field Name and Description |
---|---|---|---|
31 | 0h | RW | ISH2HOST Doorbell Busy (BUSY) When this bit is cleared, the HOST CPU is Ready to accept a new message. |
30:0 | 0h | RW | ISH2HOST Doorbell Payload (PAYLOAD_31BIT) 31bits message payload for backward compatibility. |