SPRUGR9H November   2010  – April 2015 66AK2E05 , 66AK2H06 , 66AK2H12 , 66AK2H14 , 66AK2L06 , AM5K2E02 , AM5K2E04 , SM320C6678-HIREL , TMS320C6652 , TMS320C6654 , TMS320C6655 , TMS320C6657 , TMS320C6670 , TMS320C6671 , TMS320C6672 , TMS320C6674 , TMS320C6678

 

  1.   Preface
    1.     About This Manual
    2.     Trademarks
    3.     Notational Conventions
    4.     Related Documentation from Texas Instruments
  2. 1Introduction
    1. 1.1  Terminology Used in This Document
    2. 1.2  KeyStone I Features
    3. 1.3  KeyStone I Functional Block Diagram
    4. 1.4  KeyStone II Changes to QMSS
    5. 1.5  KeyStone II QMSS Modes of Use
      1. 1.5.1 Shared Mode
      2. 1.5.2 Split Mode
    6. 1.6  Overview
    7. 1.7  Queue Manager
    8. 1.8  Packet DMA (PKTDMA)
    9. 1.9  Navigator Cloud
    10. 1.10 Virtualization
    11. 1.11 ARM-DSP Shared Use
    12. 1.12 PDSP Firmware
  3. 2Operational Concepts
    1. 2.1 Packets
    2. 2.2 Queues
      1. 2.2.1 Packet Queuing
      2. 2.2.2 Packet De-queuing
      3. 2.2.3 Queue Proxy
    3. 2.3 Queue Types
      1. 2.3.1 Transmit Queues
      2. 2.3.2 Transmit Completion Queues
      3. 2.3.3 Receive Queues
      4. 2.3.4 Free Descriptor Queues (FDQ)
        1. 2.3.4.1 Host Packet Free Descriptors
        2. 2.3.4.2 Monolithic Free Descriptors
      5. 2.3.5 Queue Pend Queues
    4. 2.4 Descriptors
      1. 2.4.1 Host Packet
      2. 2.4.2 Host Buffer
      3. 2.4.3 Monolithic Packet
    5. 2.5 Packet DMA
      1. 2.5.1 Channels
      2. 2.5.2 RX Flows
    6. 2.6 Packet Transmission Overview
    7. 2.7 Packet Reception Overview
    8. 2.8 ARM Endianess
  4. 3Descriptor Layouts
    1. 3.1 Host Packet Descriptor
    2. 3.2 Host Buffer Descriptor
    3. 3.3 Monolithic Descriptor
  5. 4Registers
    1. 4.1 Queue Manager
      1. 4.1.1 Queue Configuration Region
        1. 4.1.1.1 Revision Register (0x00000000)
        2. 4.1.1.2 Queue Diversion Register (0x00000008)
        3. 4.1.1.3 Linking RAM Region 0 Base Address Register (0x0000000C)
        4. 4.1.1.4 Linking RAM Region 0 Size Register (0x00000010)
        5. 4.1.1.5 Linking RAM Region 1 Base Address Register (0x00000014)
        6. 4.1.1.6 Free Descriptor/Buffer Starvation Count Register N (0x00000020 + N×4)
      2. 4.1.2 Queue Status RAM
      3. 4.1.3 Descriptor Memory Setup Region
        1. 4.1.3.1 Memory Region R Base Address Register (0x00000000 + 16×R)
        2. 4.1.3.2 Memory Region R Start Index Register (0x00000004 + 16×R)
        3. 4.1.3.3 Memory Region R Descriptor Setup Register (0x00000008 + 16×R)
      4. 4.1.4 Queue Management/Queue Proxy Regions
        1. 4.1.4.1 Queue N Register A (0x00000000 + 16×N)
        2. 4.1.4.2 Queue N Register B (0x00000004 + 16×N)
        3. 4.1.4.3 Queue N Register C (0x00000008 + 16×N)
        4. 4.1.4.4 Queue N Register D (0x0000000C + 16×N)
      5. 4.1.5 Queue Peek Region
        1. 4.1.5.1 Queue N Status and Configuration Register A (0x00000000 + 16×N)
        2. 4.1.5.2 Queue N Status and Configuration Register B (0x00000004 + 16×N)
        3. 4.1.5.3 Queue N Status and Configuration Register C (0x00000008 + 16×N)
        4. 4.1.5.4 Queue N Status and Configuration Register D (0x0000000C + 16×N)
    2. 4.2 Packet DMA
      1. 4.2.1 Global Control Registers Region
        1. 4.2.1.1 Revision Register (0x00)
        2. 4.2.1.2 Performance Control Register (0x04)
        3. 4.2.1.3 Emulation Control Register (0x08)
        4. 4.2.1.4 Priority Control Register (0x0C)
        5. 4.2.1.5 QMn Base Address Register (0x10, 0x14, 0x18, 0x1c)
      2. 4.2.2 TX DMA Channel Configuration Region
        1. 4.2.2.1 TX Channel N Global Configuration Register A (0x000 + 32×N)
        2. 4.2.2.2 TX Channel N Global Configuration Register B (0x004 + 32×N)
      3. 4.2.3 RX DMA Channel Configuration Region
        1. 4.2.3.1 RX Channel N Global Configuration Register A (0x000 + 32×N)
      4. 4.2.4 RX DMA Flow Configuration Region
        1. 4.2.4.1 RX Flow N Configuration Register A (0x000 + 32×N)
        2. 4.2.4.2 RX Flow N Configuration Register B (0x004 + 32×N)
        3. 4.2.4.3 RX Flow N Configuration Register C (0x008 + 32×N)
        4. 4.2.4.4 RX Flow N Configuration Register D (0x00C + 32×N)
        5. 4.2.4.5 RX Flow N Configuration Register E (0x010 + 32×N)
        6. 4.2.4.6 RX Flow N Configuration Register F (0x014 + 32×N)
        7. 4.2.4.7 RX Flow N Configuration Register G (0x018 + 32×N)
        8. 4.2.4.8 RX Flow N Configuration Register H (0x01C + 32×N)
      5. 4.2.5 TX Scheduler Configuration Region
        1. 4.2.5.1 TX Channel N Scheduler Configuration Register (0x000 + 4×N)
    3. 4.3 QMSS PDSPs
      1. 4.3.1 Descriptor Accumulation Firmware
        1. 4.3.1.1 Command Buffer Interface
        2. 4.3.1.2 Global Timer Command Interface
        3. 4.3.1.3 Reclamation Queue Command Interface
        4. 4.3.1.4 Queue Diversion Command Interface
      2. 4.3.2 Quality of Service Firmware
        1. 4.3.2.1 QoS Algorithms
          1. 4.3.2.1.1 Modified Token Bucket Algorithm
        2. 4.3.2.2 Command Buffer Interface
        3. 4.3.2.3 QoS Firmware Commands
        4. 4.3.2.4 QoS Queue Record
        5. 4.3.2.5 QoS Cluster Record
        6. 4.3.2.6 RR-Mode QoS Cluster Record
        7. 4.3.2.7 SRIO Queue Monitoring
          1. 4.3.2.7.1 QoS SRIO Queue Monitoring Record
      3. 4.3.3 Open Event Machine Firmware
      4. 4.3.4 Interrupt Operation
        1. 4.3.4.1 Interrupt Handshaking
        2. 4.3.4.2 Interrupt Processing
        3. 4.3.4.3 Interrupt Generation
        4. 4.3.4.4 Stall Avoidance
      5. 4.3.5 QMSS PDSP Registers
        1. 4.3.5.1 Control Register (0x00000000)
        2. 4.3.5.2 Status Register (0x00000004)
        3. 4.3.5.3 Cycle Count Register (0x0000000C)
        4. 4.3.5.4 Stall Count Register (0x00000010)
    4. 4.4 QMSS Interrupt Distributor
      1. 4.4.1 INTD Register Region
        1. 4.4.1.1  Revision Register (0x00000000)
        2. 4.4.1.2  End Of Interrupt (EOI) Register (0x00000010)
        3. 4.4.1.3  Status Register 0 (0x00000200)
        4. 4.4.1.4  Status Register 1 (0x00000204)
        5. 4.4.1.5  Status Register 2 (0x00000208)
        6. 4.4.1.6  Status Register 3 (0x0000020c)
        7. 4.4.1.7  Status Register 4 (0x00000210)
        8. 4.4.1.8  Status Clear Register 0 (0x00000280)
        9. 4.4.1.9  Status Clear Register 1 (0x00000284)
        10. 4.4.1.10 Status Clear Register 4 (0x00000290)
        11. 4.4.1.11 Interrupt N Count Register (0x00000300 + 4xN)
  6. 5Mapping Information
    1. 5.1 Queue Maps
    2. 5.2 Interrupt Maps
      1. 5.2.1 KeyStone I TCI661x, C6670, C665x devices
      2. 5.2.2 KeyStone I TCI660x, C667x devices
      3. 5.2.3 KeyStone II devices
    3. 5.3 Memory Maps
      1. 5.3.1 QMSS Register Memory Map
      2. 5.3.2 KeyStone I PKTDMA Register Memory Map
      3. 5.3.3 KeyStone II PKTDMA Register Memory Map
    4. 5.4 Packet DMA Channel Map
  7. 6Programming Information
    1. 6.1 Programming Considerations
      1. 6.1.1 System Planning
      2. 6.1.2 Notification of Completed Work
    2. 6.2 Example Code
      1. 6.2.1 QMSS Initialization
      2. 6.2.2 PKTDMA Initialization
      3. 6.2.3 Normal Infrastructure DMA with Accumulation
      4. 6.2.4 Bypass Infrastructure notification with Accumulation
      5. 6.2.5 Channel Teardown
    3. 6.3 Programming Overrides
    4. 6.4 Programming Errors
    5. 6.5 Questions and Answers
  8. AExample Code Utility Functions
  9. BExample Code Types
  10. CExample Code Addresses
    1. C.1 KeyStone I Addresses:
    2. C.2 KeyStone II Addresses:
  11.   Revision History

3.2 Host Buffer Descriptor

The host buffer descriptor is identical in size and organization to a host packet descriptor but does not include valid information in the packet level fields and does not include a populated region for protocol-specific information. Host buffer descriptors are designed to be linked onto a host packet descriptor or another host buffer descriptor to provide support for unlimited scatter / gather type operations. Host buffer descriptors provide information about a single corresponding data buffer. Every host buffer descriptor stores the following information:

  • Pointer to the first valid byte in the data buffer
  • Length of the data buffer
  • Pointer to the next buffer descriptor in the packet

Host buffer descriptors always contain 32 bytes of required information. Because it is a requirement that it is possible to convert a host descriptor between a buffer descriptor and a packet descriptor (by filling in the appropriate fields), in practice, host buffer descriptors will be allocated using the same sizes as host packet descriptors. The descriptor layout is shown in Table 3-15.

Table 3-15 Host Buffer Descriptor Layout

Reserved
(10 bytes)
Buffer reclamation info
(2 bytes)
Buffer info (8 bytes)
Linking info (4 bytes)
Original buffer info
(8 bytes)
Reserved
(10 bytes)
Buffer reclamation info
(2 bytes)
Buffer info (8 bytes)
Linking info (4 bytes)
Original buffer info
(8 bytes)

A host packet descriptor and zero or more host buffer descriptors may be linked together using the next descriptor pointer fields to form packets. The last descriptor in a packet has a 0 next descriptor pointer. Each host buffer descriptor also points to a single data buffer.

The contents of the host buffer descriptor words are detailed in Table 3-16 through Table 3-23. The host buffer descriptor is designed to be interchangeable with host packet descriptors, with common fields residing in the same locations.

Table 3-16 Host Buffer Descriptor Reserved Word 0 (BD Word 0)

Bits Name Description RX Overwrite
31-0 Reserved Reserved for host packet fields No

Table 3-17 Host Buffer Descriptor Reserved Word 1 (BD Word 1)

Bits Name Description RX Overwrite
31-0 Reserved Reserved for host packet fields No

Table 3-18 Host Buffer Descriptor Buffer Reclamation Info (BD Word 2)

Bits Name Description RX Overwrite
31-15 Reserved Reserved for host packet fields No
14 Return Push Policy This field indicates how a transmit DMA should return the descriptor pointers to the free queues. This field is encoded as follows:
  • 0 = Descriptor must be returned to tail of queue
  • 1 = Descriptor must be returned to head of queue

This bit is used only when the Return Policy bit is set to 1.

 No
13-12 Packet Return Queue Mgr # This field indicates which of the four potential queue managers in the system the descriptor is to be returned to after transmission is complete. This field is not altered by the DMA during transmission or reception and should be initialized by the host. No
11-0 Packet Return Queue # This field indicates the queue number within the selected queue manager that the descriptor is to be returned to after transmission is complete. No

Table 3-19 Host Buffer Descriptor Buffer N Info Word 0 (BD Word 3)

Bits Name Description RX Overwrite
31-22 Reserved Reserved for host packet fields Yes
21-0 Buffer N Length The buffer length field indicates how many valid data bytes are in the buffer. Unused or protocol-specific bytes at the beginning of the buffer are not counted in the buffer length field. This value will be overwritten during reception. Yes

Table 3-20 Host Buffer Descriptor Buffer N Info Word 1 (BD Word 4)

Bits Name Description RX Overwrite
31-0 Buffer N Pointer The buffer pointer is the byte-aligned memory address of the buffer associated with the buffer descriptor. This value will not be overwritten during reception. Yes

Table 3-21 Host Buffer Descriptor Linking Word (BD Word 5)

Bits Name Description RX Overwrite
31-0 Next Descriptor Pointer The 32-bit word aligned memory address of the next buffer descriptor in the packet. This is the mechanism used to reference the next buffer descriptor from the current buffer descriptor. If the value of this pointer is 0, then the current buffer is the last buffer in the packet. This value will be overwritten during reception. Yes

Table 3-22 Host Buffer Descriptor Original Buffer Info Word 0 (BD Word 6)

Bits Name Description RX Overwrite
31-28 Original Buffer 0 Pool Index This field is used to identify which pool the attached buffer was originally allocated from. This is distinct from the descriptor pool/queue index because a single buffer may be referenced by more that one descriptor. This is a software-only field that is not touched by the hardware. No
27-22 Original Buffer 0 Reference Count This field is used to indicate how many references have been made to the attached buffer by different descriptors. Multiple buffer references are commonly used to implement broadcast and multicast packet forwarding when zero packet data copies are desired. This is a software-only field that is not touched by the hardware. No
21-0 Original Buffer 0 Length The buffer length field indicates the original size of the buffer in bytes. Data bytes are in the buffer. This value will not be overwritten during reception. This value is read by the RX DMA to determine the actual buffer size as allocated by the host at initialization. Because the buffer length in word 3 is overwritten by the RX port during reception, this field is necessary to permanently store the buffer size information. No

Table 3-23 Host Buffer Descriptor Original Buffer Info Word 1 (BD Word 7)

Bits Name Description RX Overwrite
31-0 Original Buffer 0 Pointer The buffer pointer is the byte-aligned memory address of the buffer associated with the buffer descriptor. This value will not be overwritten during reception. This value is read by the RX DMA to determine the actual buffer location as allocated by the host at initialization. Because the buffer pointer in word 4 is overwritten by the RX port during reception, this field is necessary to permanently store the buffer pointer information. No