Mechanism to boot multiple hosts from a shared PCIe device
View Patent ↗A PCIe switch including a memory and a processor. The processor is operable to receive a transaction from an information handling system to an endpoint device, determine that the transaction is a request to receive firmware code from the endpoint device, block the transaction from being issued to the endpoint device, and provide the firmware code to the information handling system from the memory.
1. A Peripheral Component Interconnect Express (PCIe) switch comprising:
a memory to store a first base address in an endpoint device, wherein the first base address points to a first location of firmware code in a physical function of the endpoint device; and
a processor configured to:
receive a first transaction from a first information handling system to the physical function of the endpoint device;
determine that the first information handling system can not access firmware code from the endpoint device, based upon the first transaction being to the physical function;
block the first transaction from being issued to the endpoint device;
provide the firmware code to the first information handling system from the memory in response to the first transaction;
prior to receiving the first transaction, receive a second transaction from a second information handling system to the physical function of the endpoint device;
determine that the second transaction is a second request to receive the firmware code from the endpoint device;
receive a third transaction from the endpoint device, the third transaction including the firmware code; and
store the firmware code in the memory.
2. The PCIe switch of claim 1 , wherein:
in providing the firmware code to the first information handling system, the processor is further configured to:
provide a second base address to the first information handling system, the second base address being to a second location of the firmware code in the memory; and
receive a second transaction from the first information handling system to the second base address; and
providing the firmware code to the first information handling system is in response to the second transaction.
3. The PCIe switch of claim 1 , wherein the first transaction is to a virtual function of the endpoint device.
4. The PCIe switch of claim 1 , wherein the processor is further configured to:
prior to receiving the third transaction, receive a fourth transaction from the endpoint device, the fourth transaction including a base address in the endpoint device, wherein the base address points to a location of the firmware code in the endpoint device; and
store the base address in the memory.
5. The PCIe switch of claim 2 , wherein the second transaction is to the physical function of the endpoint device.
6. The PCIe switch of claim 1 , wherein:
the PCIe switch is a multi-root I/O virtualization switch; and
the endpoint device is a single-root I/O virtualization endpoint device.
7. A method comprising:
receiving, at a Peripheral Component Interconnect-Express (PCIe) switch, a first transaction from a first information handling system to a physical function of an endpoint device;
determining that the first information handling system can not access firmware code from the endpoint device, based upon the first transaction being to the physical function;
blocking the first transaction from being issued to the endpoint device;
providing, in response to the first transaction, the firmware code to the first information handling system from a memory of the PCIe switch;
prior to receiving the first transaction and the second transaction, receiving a third transaction from a second information handling system to the endpoint device;
determining that the third transaction is a second request to receive the firmware code from the endpoint device;
receiving a fourth transaction from the endpoint device, the fourth transaction including the firmware code; and
storing the firmware code in the memory.
8. The method of claim 7 , wherein providing the firmware code includes:
providing a second base address to the first information handling system, wherein the second base address points to a second location of the firmware code in the memory; and
receiving a second transaction from the first information handling system to the second base address.
9. The method of claim 7 , wherein the first transaction is to a virtual function of the endpoint device.
10. The method of claim 7 , further comprising:
prior to receiving the third transaction, receiving a fourth transaction from the endpoint device, the fourth transaction including a base address in the endpoint device, wherein the base address points to a location of the firmware code in the endpoint device; and
storing the base address in the memory.
11. The method of claim 8 , wherein the second transaction is to the physical function of the endpoint device.
12. The method of claim 7 , wherein:
the PCIe switch is a multi-root I/O virtualization switch; and
the endpoint device is a single-root I/O virtualization endpoint device.
13. A non-transitory computer-readable medium including code for performing a method, the method comprising:
receiving, at a Peripheral Component Interconnect-Express (PCIe) switch, a first transaction from a first information handling system to a physical function of an endpoint device;
determining that the first information handling system can not access firmware code from the endpoint device, based upon the first transaction being to the physical function of the endpoint device;
blocking the first transaction from being issued to the endpoint device;
providing, in response to the first transaction, the firmware code to the first information handling system from a memory of the PCIe switch;
prior to receiving the first transaction and the second transaction, receiving a third transaction from a second information handling system to the endpoint device;
determining that the third transaction is a second request to receive the firmware code from the endpoint device;
receiving a fourth transaction from the endpoint device, the fourth transaction including the firmware code; and
storing the firmware code in the memory.
14. The computer-readable medium of claim 13 , wherein in providing the firmware code, the method further comprises:
providing a second base address to the first information handling system, wherein the second base address points to a second location of the firmware code in the memory; and
receiving a second transaction from the first information handling system to the second base address.
15. The computer-readable medium of claim 13 , wherein the first transaction is to a virtual function of the endpoint device.
16. The computer-readable medium of claim 13 , the method further comprising:
prior to receiving the third transaction, receiving a fourth transaction from the endpoint device, the fourth transaction including a base address in the endpoint device, wherein the base address points to a location of the firmware code in the endpoint device; and
storing the base address in the memory.
17. The computer-readable medium of claim 14 , wherein the second transaction is to the physical function of the endpoint device.