Device hot plug system
A device hot-plug system includes a chassis. A connector is included in the chassis. A reset pin is included on the connector. A hot-plug device is configured, in response to being hot-plugged to the connector, to enter a device reset state. While in the device reset state, the hot-plug device monitors a reference clock and determines that the reference clock has been stable for a predetermined time period. In response to determining that the reference clock has been stable for a predetermined time period, the hot-plug device exits the device reset state and provides a de-assertion signal on the reset pin.
1. A device hot-plug system, comprising:
a chassis;
a connector included in the chassis;
a reset pin included on the connector; and
a hot-plug device that is configured, in response to being hot-plugged to the connector, to:
enter a device reset state;
monitor, while in the device reset state, a reference clock;
determine, while in the device reset state, that the reference clock has been stable for a predetermined time period;
exit, in response to determining that the reference clock has been stable for the predetermined time period, the device reset state; and
provide, in response to exiting the device reset state, a de-assertion signal on the reset pin.
2. The system of claim 1 , further comprising:
a plurality of communication pins included on the connector, wherein the hot-plug device is configured, in response to being hot-plugged to the connector, to:
determine, while in the device reset state, that each of the plurality of communication pins have been engaged; and
exit, in response to determining that each of the plurality of communication pins have been engaged and that the reference clock has been stable for the predetermined time period, the device reset state.
3. The system of claim 1 , wherein the reference clock is housed in the chassis and coupled to at least one reference clock pin that is included on the connector, and wherein the hot-plug device is configured to determine that the reference clock has been stable for the predetermined time period via the at least one reference clock pin.
4. The system of claim 1 , wherein the reference clock is included in the hot-plug device, and wherein the hot-plug device is configured to determine that the reference clock has been stable for the predetermined time period by monitoring the reference clock included in the hot-plug device.
5. The system of claim 1 , further comprising:
at least one register that is included in the hot-plug device, wherein the predetermined time period is designated by the at least one register.
6. The system of claim 1 , wherein the connector is a Peripheral Component Interconnect express (PCIe) Non-Volatile Memory (NVMe) device connector, and wherein the hot-plug device is an NVMe device.
7. An Information Handling System (IHS), comprising:
a processing system; and
a memory system that is coupled to the processing system and that includes instructions that, when executed by the processing system, cause the processing system to provide a hot-plug engine that is configured, in response to a hot-plug event with a connector, to:
enter a reset state;
monitor, while in the reset state, a reference clock;
determine, while in the reset state, that the reference clock has been stable for a predetermined time period;
exit, in response to determining that the reference clock has been stable for the predetermined time period, the reset state; and
provide, in response to exiting the reset state, a de-assertion signal on a reset pin included on the connector.
8. The IHS of claim 7 , wherein the hot-plug engine is configured, in response to the hot-plug event with the connector, to:
determine, while in the reset state, that each of a plurality of communication pins on the connector have been engaged; and
exit, in response to determining that each of the plurality of communication pins have been engaged and that the reference clock has been stable for the predetermined time period, the reset state.
9. The IHS of claim 7 , wherein the reference clock is coupled to at least one reference clock pin that is included on the connector, and wherein the hot-plug engine is configured to determine that the reference clock has been stable for the predetermined time period via the at least one reference clock pin.
10. The IHS of claim 7 , wherein the reference clock that is directly connected to the processing system, wherein the hot-plug engine is configured to determine that the reference clock has been stable for the predetermined time period by monitoring the reference clock directly connected to the processing system.
11. The IHS of claim 7 , further comprising:
at least one register that is coupled to the processing system, wherein the predetermined time period is designated by the at least one register.
12. The IHS of claim 7 , wherein the connector is a Peripheral Component Interconnect express (PCIe) Non-Volatile Memory (NVMe) device connector.
13. The IHS of claim 7 , further comprising:
a chassis housing the processing system and the memory system; and
a securing latch that is included on the chassis and that is configured to activate a securing subsystem that causes sequential engagement of pins on the connector.
14. A method for hot-plugging a device, comprising:
entering, by a hot-plug device in response to being hot-plugged to a connector, a device reset state;
monitoring, by the hot-plug device while in the device reset state, a reference clock;
determining, by the hot-plug device while in the device reset state, that the reference clock has been stable for a predetermined time period;
exiting, by the hot-plug device in response to determining that the reference clock has been stable for the predetermined time period, the reset state; and
providing, by the hot-plug device in response to exiting the reset state, a de-assertion signal on a reset pin included on the connector.
15. The method of claim 14 , further comprising:
determining, by the hot-plug device while in the device reset state, that each of a plurality of communication pins on the connector have been engaged; and
exiting, by the hot-plug device in response to determining that each of the plurality of communication pins have been engaged and that the reference clock has been stable for the predetermined time period, the device reset state.
16. The method of claim 14 , wherein the reference clock is coupled to at least one reference clock pin that is included on the connector, and wherein the hot-plug device is configured to determine that the reference clock has been stable for the predetermined time period via the at least one reference clock pin.
17. The method of claim 14 , wherein the reference clock is included in the hot-plug device, and wherein the hot-plug device is configured to determine that the reference clock has been stable for the predetermined time period by monitoring the reference clock included in the hot-plug device.
18. The method of claim 14 , wherein the predetermined time period is designated by at least one register that is included in the hot-plug device.
19. The method of claim 14 , wherein the connector is a Peripheral Component Interconnect express (PCIe) Non-Volatile Memory (NVMe) device connector, and wherein the hot-plug device is an NVMe device.
20. The method of claim 14 , further comprising:
a securing latch that is included on the hot-plug device and that is configured to activate a securing subsystem that causes sequential engagement of pins on the connector.