System and method for port migration in a PCIE switch
The present disclosure provides a method and system for dynamically migrating a port in a PCIe switch. The PCIe switch comprises emulated P2P bridges stored in a memory and a processor to load the emulated P2P bridge address range values from the memory to a routing table. The processor can configure the routing table so that the P2P bridges can be remapped to various physical ports of the switch. Therefore, a device connected to a physical port may be migrated from one host to another, via the operations of the processor.
1. A PCIe switch comprising:
a plurality of ports, comprising at least one upstream port and at least one downstream port;
a switch fabric electrically connected to the plurality of ports;
a routing table in communication with the switch fabric;
a memory; and
a processor in communication with the switch fabric, the routing table and the memory for:
creating a first configuration space of a first emulated P2P (PCI to PCI) bridge in the memory, the first emulated P2P bridge being associated with a first logical switch partition;
receiving a request to migrate a selected downstream port to the first logical switch partition, the selected downstream port having a port ID and being associated with a second logical switch partition
retrieving a first address range from the first configuration space in the memory; and
configuring the routing table to associate the port ID of the selected downstream port with the first address range, wherein:
the memory stores a second address range in a second configuration space of a second emulated P2P bridge associated with a second logical switch partition; and
the processor is further configured to unbind the second emulated P2P bridge from the selected downstream port by configuring the routing table to dissociate the port ID of the selected downstream port with the second address range.
2. The PCIe switch of claim 1 , wherein:
the first configuration space is programmed by a first host to comprise a first endpoint device address range; and
the second configuration space is programmed by a second host to comprise a second endpoint device address range.
3. The PCIe switch of claim 2 , wherein configuring the routing table to associate the port ID of the selected downstream port with the first address range comprises creating, in the routing table, an entry associating the first endpoint device address range with the port ID of the selected downstream port.
4. The PCIe switch of claim 3 , wherein the processor is further configured to:
receive an instruction to bind the selected downstream port to the first emulated P2P bridge;
program the memory to indicate in the first configuration space that the first emulated P2P bridge is bound to the selected downstream port;
release a reset state of the selected downstream port; and
send an interrupt signal to the host.
5. The PCIe switch of claim 2 , wherein configuring the routing table to dissociate the port ID of the selected downstream port with the second address range comprises deleting, in the routing table, an entry associating the second endpoint device address range with the port ID of the selected downstream port.
6. The PCIe switch of claim 5 , wherein the processor is further configured to:
receive an instruction to unbind the selected downstream port from the second emulated P2P bridge;
send an interrupt signal to the host;
place the selected downstream port in a reset state; and
program the memory to indicate in the second configuration space that the second emulated P2P bridge has no device attached.
7. A method for migrating a downstream port in a PCIe switch, the method comprising:
creating a first configuration space of a first emulated P2P (PCI to PCI) bridge in a memory, the first emulated P2P bridge being associated with a first logical switch partition;
receiving, at a processor, a request to migrate the downstream port to the first logical switch partition, the downstream port having a port ID and being associated with a second logical switch partition;
retrieving a first address range from the first configuration space in the memory; and configuring a routing table to associate the port ID of the downstream port with the first address range;
storing in memory a second address range in a second configuration space of a second emulated P2P bridge associated with a second logical switch partition; and
unbinding the second emulated P2P bridge from the port by configuring the routing table to dissociate the port ID of the downstream port with the second address range.
8. The method of claim 7 , wherein:
the first configuration space is programmed by a first host to comprise a first endpoint device address range; and
the second configuration space is programmed by a second host to comprise a second endpoint device address range.
9. The method of claim 8 , wherein configuring the routing table to associate the port ID of the downstream port with the first address range comprises creating, in the routing table, an entry associating the first endpoint device address range with the port ID of the downstream port.
10. The method of claim 9 , further comprising:
receiving an instruction to bind the downstream port to the first emulated P2P bridge;
programming the memory to indicate in the first configuration space that the emulated P2P bridge is bound to the downstream port;
releasing a reset state of the downstream port; and
sending an interrupt signal to the host.
11. The method of claim 8 , wherein configuring the routing table to dissociate the port ID of the downstream port with the second address rage comprises deleting, in the routing table, an entry associating the second endpoint device address range with the port ID of the downstream port.
12. The method of claim 11 , further comprising:
receiving an instruction to unbind the downstream port from the second emulated P2P bridge;
sending an interrupt signal to the host;
placing the downstream port in a reset state; and
programming the memory to indicate in the second configuration space that the second emulated P2P bridge has no device attached.