MEMORY MANAGEMENT FOR HIGH SPEED MEDIA ACCESS CONTROL

• US 20070230493A1
• Filed: 03/30/2007
• Published: 10/04/2007
• Est. Priority Date: 03/31/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Dravida, Subrahmanyam, Narayan, Sriram
• Granted Patent: US 8,139,593 B2
• Time in Patent Office: Days
• US Class Current: 370/412
• CPC Class Codes: H04L 47/621 Individual queue per connection or flow, e.g. per VC
• CPC Class Codes: H04L 49/901 using storage descriptor, e.g. read or write pointers
• CPC Class Codes: H04L 49/9015 for supporting a linked list
• CPC Class Codes: H04L 49/9021 Plurality of buffers per packet
• CPC Class Codes: H04L 49/9073 Early interruption upon arrival of a fraction of a packet
• CPC Class Codes: H04W 36/02 Buffering or recovering information during reselection ; Modification of the traffic flow during hand-off
• CPC Class Codes: H04W 76/20 Manipulation of established connections
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Aspects disclosed herein address the need in the art for memory management for high speed media access control. A packet buffer may store packets with a first data structure, comprising the packet length, sequence number, and a pointer to a second data structure. Packet data may be stored in a linked list of one or more second data structures. Transmit and receive queues may be formed using linked lists or arrays of the first data structures. Memory locations for storing first and second data structures may be kept in lists indicating free locations for the respective data structure types. A flexible memory architecture is disclosed in which two configurations may be selected. In a first configuration, a first memory comprises per-flow parameters for multiple flows, and a second memory comprises a packet buffer. In a second configuration, the first memory comprises per-flow pointers to per-flow parameters in the second memory. The packet buffer resides in a third memory. Various other aspects are also presented.

Claims

1. A method comprising:

storing in a first data structure in a packet buffer the length of a first packet, the sequence number of the packet, and a second packet buffer location of a second data structure in the packet buffer; and

storing data from the first packet in the second data structure identified by the stored second packet buffer location.

2. The method of claim 1, further comprising:

storing in a third data structure in the packet buffer the length of a second packet, the sequence number of the second packet, and a fourth packet buffer location of a fourth data structure in the packet buffer;

storing data from the second packet in the fourth data structure identified by the stored fourth packet buffer location; and

storing the location of the third data structure in the first data structure.

3. The method of claim 1, further comprising forming a packet queue by storing a linked list of a plurality of first data structures, each first data structure associated with one of a plurality of packets.

4. The method of claim 1, further comprising forming an array of first data structures, each first data structure associated with one of a plurality of packets.

5. The method of claim 1, further comprising forming a free first data structure pointer list, the free first data structure pointer list comprising one or more first data structure pointers for associating with a first data structure.

6. The method of claim 5, further comprising:

retrieving a first data structure pointer from the free first data structure pointer list;

removing the retrieved first data structure pointer from the free first data structure pointer list; and

storing the first data structure in the packet buffer at a location identified by the retrieved first data structure pointer.

7. The method of claim 5, further comprising adding a previously removed first data structure pointer to the free first data structure pointer list to remove the first data structure from the packet buffer.

8. The method of claim 1, further comprising forming a free second data structure pointer list, the free second data structure pointer list comprising one or more pointers for associating with a second data structure.

9. The method of claim 8, further comprising:

retrieving a second data structure pointer from the free second data structure pointer list;

removing the retrieved second data structure pointer from the free second data structure pointer list; and

storing the retrieved second data structure pointer in the second packet buffer location of the first data structure.

10. The method of claim 9, further comprising storing the second data structure in the packet buffer at a location identified by the retrieved second data structure pointer.

11. The method of claim 8, further comprising adding a previously removed second data structure pointer to the free second data structure pointer list to remove the second data structure from the packet buffer.

12. The method of claim 11, wherein the second packet buffer location of the second data structure in the packet buffer is stored in a second data structure pointer field of the first data structure, and further comprising retrieving a second data structure from the packet buffer, the second data structure identified by the second data structure pointer field of the first data structure.

13. An apparatus comprising:

means for storing in a first data structure in a packet buffer the length of a first packet, the sequence number of the packet, and a second packet buffer location of a second data structure in the packet buffer; and

means for storing data from the first packet in the second data structure identified by the stored second packet buffer location.

14. The apparatus of claim 13, further comprising:

means for storing in a third data structure in the packet buffer the length of a second packet, the sequence number of the second packet, and a fourth packet buffer location of a fourth data structure in the packet buffer;

means for storing data from the second packet in the fourth data structure identified by the stored fourth packet buffer location; and

means for storing the location of the third data structure in the first data structure.

15. The apparatus of claim 13, further comprising means for forming a packet queue by storing a linked list of a plurality of first data structures, each first data structure associated with one of a plurality of packets.

16. The apparatus of claim 13, further comprising means for forming an array of first data structures, each first data structure associated with one of a plurality of packets.

17. An apparatus comprising:

a first memory,

configured in a first mode to store one or more parameters for each of a plurality of communication flows and

configured in a second mode to store a pointer for each of the plurality of communication flows, each pointer indicating a location associated with the respective communication flow;

a second memory,

configured in the first mode to store packets for each of the plurality of communication flows and

configured in the second mode to store a plurality of sets of one or more parameters for each of the plurality of communication flows, each set of one or more parameters stored in the location indicated by the pointer associated with the respective communication flow;

a memory interface operable with a third memory,

configured in the second mode to be operative to store packets for each of the plurality of communication flows; and

a processor selecting a selected mode as the first mode or the second mode, configuring the first memory according to the selected mode, configuring the second memory according to the selected mode, and configuring the memory interface according to the selected mode.

18. The apparatus of claim 17, wherein the second memory, when configured in the first mode, comprises a packet buffer, the packet buffer comprising:

a first data structure associated with a packet; and

a second data structure comprising data from the associated packet; and

wherein the first data structure comprises;

a length field indicating the length of the associated packet;

a sequence number field indicating the sequence number of the associated packet; and

a second data structure pointer field indicating the location in the packet buffer of the second data structure.

19. The apparatus of claim 18, further wherein the memory interface, when configured in the second mode, is operable to store packets in a packet buffer in the third memory, the memory interface for storing:

a first data structure associated with a packet; and

a second data structure comprising data from the associated packet; and

wherein the first data structure comprises;

a length field indicating the length of the associated packet;

a sequence number field indicating the sequence number of the associated packet; and

a second data structure pointer field indicating the location in the packet buffer of the second data structure.

20. A wireless communication device comprising:

a first integrated circuit, comprising;

a first memory,

configured in a first mode to store one or more parameters for each of a plurality of communication flows and

configured in a second mode to store a pointer for each of the plurality of communication flows, each pointer indicating a location associated with the respective communication flow;

a second memory,

configured in the first mode to store packets for each of the plurality of communication flows and

configured in the second mode to store a plurality of sets of one or more parameters for each of the plurality of communication flows, each set of one or more parameters stored in the location indicated by the pointer associated with the respective communication flow;

a memory interface operable with a third memory,

configured in the second mode to be operative to store packets for each of the plurality of communication flows; and

a processor selecting a selected mode as the first mode or the second mode, configuring the first memory according to the selected mode, configuring the second memory according to the selected mode, and configuring the memory interface according to the selected mode; and

a second integrated circuit comprising a third memory storing packets for each of the plurality of communication flows, coupled with the memory interface of the first integrated circuit.

21. A wireless communication device comprising:

a first memory storing one or more parameters for each of a plurality of communication flows; and

a second memory storing packets for each of the plurality of communication flows, comprising;

a first data structure associated with a packet; and

a second data structure comprising data from the associated packet; and

wherein the first data structure comprises;

a length field indicating the length of the associated packet;

a sequence number field indicating the sequence number of the associated packet; and

a second data structure pointer field indicating the location in the second memory of the second data structure.

22. The wireless communication device of claim 21, wherein the first data structure further comprises a next first data pointer field indicating the location in the second memory of a second first data structure.

23. The wireless communication device of claim 22, further comprising a packet queue of a plurality of packets, the queue formed by a linked list of a plurality of first data structures, each first data structure associated with one of the plurality of packets, the order of the queue determined by linking each of the plurality of first data structures in the linked list in accordance with the next first data pointer field of each respective first data structure.

24. Computer readable media including instructions thereon, the instructions comprising:

instructions for selecting a first or second mode;

instructions for configuring a first memory in a first mode to store one or more parameters for each of a plurality of communication flows;

instructions for configuring the first memory in a second mode to store a pointer for each of the plurality of communication flows, each pointer indicating a location associated with the respective communication flow;

instructions for configuring a second memory in the first mode to store packets for each of the plurality of communication flows;

instructions for configuring the second memory in the second mode to store a plurality of sets of one or more parameters for each of the plurality of communication flows, each set of one or more parameters stored in the location indicated by the pointer associated with the respective communication flow; and

instructions for configuring a memory interface operable with a third memory in the second mode to be operative to store packets for each of the plurality of communication flows.