Address Range Decomposition

Patent metadata

Field	Value
Publication number	US-2015161068-A1
Application number	US-201314097924-A
Country	US
Kind code	A1
Filing date	Dec 5, 2013
Priority date	Dec 5, 2013
Publication date	Jun 11, 2015
Grant date	—

Abstract

Smart bridge and use. The smart bridge includes a functional unit, memory, and a switch for routing data between a host and multiple devices using a routing table. The bridge stores a forwarding address range (FAR) as a bridge representation of hardware memory resources required by the devices. The FAR is an integer multiple of a first specified minimum size and is aligned with the first specified minimum size. The bridge representation is converted to an endpoint representation that includes multiple virtual memory resources based on a starting address of the FAR. Each virtual memory resource has a respective sub-address range with a size that is a power of 2 multiple of a second specified minimum size, which is less than the first specified minimum size, and is aligned accordingly. The endpoint representation is usable by the switch or the host to allocate the virtual memory resources to the devices.

First claim

We claim:

1 . A smart bridge, configured to be interposed between a bus host device and a plurality of devices that require respective amounts of memory resources of the bus host device, wherein the smart bridge comprises:
a functional unit; memory, coupled to the functional unit; and at least one switch, coupled to the functional unit, wherein the at least one switch is configured to route data between the bus host device and the plurality of devices using a routing table; wherein the memory stores program instructions executable by the functional unit to:
store a forwarding address range comprising a bridge representation of a plurality of hardware memory resources required by a plurality of devices, wherein the forwarding address range is an integer multiple of a first specified minimum size and is aligned with the first specified minimum size; and
convert the bridge representation of the plurality of hardware memory resources to an endpoint representation comprising a plurality of virtual memory resources based on a starting address of the forwarding address range, wherein each virtual memory resource comprises a respective sub-address range with a size that is a power of 2 multiple of a second specified minimum size and is aligned with its size, wherein the second specified minimum size is less than the first specified minimum size; and
wherein the endpoint representation is usable by the at least one switch or the bus host device to allocate the virtual memory resources to the plurality of devices.

2 . The smart bridge of claim 1 , wherein the bridge representation and the forwarding address range are binary numbers, and wherein to convert the bridge representation of the plurality of hardware memory resources to the endpoint representation, the program instructions are executable to:
while there are virtual memory resources to allocate:
determine if a current base address of the forwarding address range is aligned;
allocate a next virtual memory resource to the forwarding address range at the current base address, where the size of the sub-address range of the virtual memory resource is based on the least significant 1 bit of the current base address, in response to determining that the starting address of the forwarding address range is not aligned; and
allocate the next virtual memory resource to the forwarding address range at the current base address, where the size of the sub-address range of the virtual memory resource is based on the most significant 1 bit of the current forwarding address size, in response to determining that the starting address of the forwarding address range is aligned.

3 . The smart bridge of claim 1 , wherein the starting address is aligned, wherein the bridge representation is a binary number, wherein the number of virtual memory resources is equal to the number of “1” bits in the bridge representation, and wherein to convert the bridge representation of the plurality of hardware memory resources to the endpoint representation, the program instructions are executable to:
for each “1” bit in the bridge representation, create a respective virtual memory resource whose size is equal to the value of the “1” bit's position; and
order the virtual memory resources based on the starting address of the forwarding address range, including assigning respective address sub-ranges to the respective virtual memory resources such that each sub-address range is aligned according to its size;
wherein the virtual memory resource sub-ranges are contiguous and compose the forwarding address range.

4 . The smart bridge of claim 3 , wherein said assigning respective address sub-ranges to the respective virtual memory resources comprises:
allocating the virtual memory resources to the forwarding address range beginning with the starting address, wherein the virtual memory resources are allocated from smallest up until an ending address of a virtual memory resource sub-range is aligned in accordance with the largest remaining virtual memory resource to be allocated; and allocating the remaining virtual memory resources from largest down.

5 . The smart bridge of claim 1 , wherein the program instructions are further executable to configure the routing table in accordance with the endpoint representation.

6 . The smart bridge of claim 1 , wherein the program instructions are further executable to implement a proxy device based on the endpoint representation, and wherein the bridge presents itself to the bus host device as the proxy device requesting the plurality of memory resources.

7 . The smart bridge of claim 1 , wherein the forwarding address range is received from a downstream bridge.

8 . The smart bridge of claim 1 , wherein the forwarding address range comprises:
the starting address; and size of the forwarding address range.

9 . The smart bridge of claim 1 , wherein the forwarding address range comprises:
the starting address; and an ending address.

10 . The smart bridge of claim 1 , wherein the smart bridge is configured to operate in accordance with a protocol, the protocol comprising one or more of:
Peripheral Component Interconnect Express (PCIe); or PXI Express (PXIe).

11 . A method, comprising:
storing, by a bridge, a forwarding address range comprising a bridge representation of a plurality of hardware memory resources required by a plurality of devices, wherein the forwarding address range is an integer multiple of a first specified minimum size and is aligned with the first specified minimum size; and converting, by the bridge, the bridge representation of the plurality of hardware memory resources to an endpoint representation comprising a plurality of virtual memory resources based on a starting address of the forwarding address range, wherein each virtual memory resource comprises a respective sub-address range with a size that is a power of 2 multiple of a second specified minimum size and is aligned with its size; wherein the endpoint representation is usable by the bridge or a bus host device to allocate the virtual memory resources to the plurality of devices.

12 . The method of claim 11 , wherein the bridge representation and the forwarding address range are binary numbers, and wherein said converting the bridge representation of the plurality of hardware memory resources to the endpoint representation comprises:
while there are virtual memory resources to allocate:
determining if a current base address of the forwarding address range is aligned;
allocating a next virtual memory resource to the forwarding address range at the current base address, where the size of the sub-address range of the virtual memory resource is based on the least significant 1 bit of the current base address, in response to determining that the starting address of the forwarding address range is not aligned; and
allocating the next virtual memory resource to the forwarding address range at the current base address, where the size of the sub-address range of the virtual memory resource is based on the most significant 1 bit of the current forwarding address size, in response to determining that the starting address of the forwarding address range is aligned.

13 . The method of claim 11 , wherein the starting address is aligned, wherein the bridge representation is a binary number, wherein the number of virtual memory resources is equal to the number of “1” bits in the bridge representation, and wherein said converting the bridge representation of the plurality of hardware memory resources to the endpoint representation comprises:
for each “1” bit in the bridge representation, creat

Assignees

• Nat Instr Corp

Inventors

• Jones Craig S

Classifications

• H04L45/02

  Topology update or discovery · CPC title

• G06F12/00

  Accessing, addressing or allocating within memory systems or architectures (digital input from, or digital output to record carriers, e.g. to disk storage units, G06F3/06) · CPC title

• H04L49/35 Primary

  Switches specially adapted for specific applications · CPC title

• G06F13/4022 Primary

  using switching circuits, e.g. switching matrix, connection or expansion network (G06F13/4009 takes precedence) · CPC title

• G06F13/404

  with address mapping · CPC title