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

4.1.4.4 Queue N Register D (0x0000000C + 16×N)

The Queue N Register D (Figure 4-14) is written to add a packet to the queue and read to pop a packet off a queue. The packet is pushed to or popped from the queue only when the Queue Register D is written.

NOTE

Remember that all accesses to Registers A, B, C and D are considered by the hardware an atomic access. If reading/writing Register C with this register, read the atomicity note in the section for Register C. Reading Registers A and B are best done using the Queue Peek region. Please see the above register descriptions for more information. Pushing to the VBUSM address is faster than the VBUSP address due to the deeper write buffer (and no stalls), but popping is faster via the VBUSP address to due the higher VBUSM SCR latency for pop operations.
Figure 4-14 Queue N Register D (0x0000000C + 16×N)
31 4 3 0
DESC_PTR DESC_SIZE
R/W-0 R/W-0
Legend: R/W = Read/Write; - n = value after reset

Table 4-17 Queue N Register D Field Descriptions

Bit Field Description
31-4 DESC_PTR Descriptor pointer. It will be read as 0 if the queue is empty. It will indicate a 16-byte-aligned address that points to a descriptor when the queue is not empty. Writing a 0 will force queue empty, possibly losing queued descriptors.
3-0 DESC_SIZE Descriptor hint size (PKTDMA pre-fetch size), encoded in 16-byte increments as follows:
  • 0 = 16 bytes
  • 1 = 32 bytes
  • 2 = 48 bytes
  • ...
  • 15 = 256 bytes.

This field should be set to the smallest value that is greater than or equal to the size of the entire control portion of the descriptor. This includes all descriptor information (including the protocol specific bytes) with the exception of the data portion of the monolithic descriptor. If this value is smaller than the control portion size of the descriptor, the PKTDMA will not fetch the remainder and will hang. For AIF Monolithic Mode, this value should always be set to 3. If the queue is empty, this field will return a 0x0 when read.

When the Packet DMA pushes descriptors to TX Return queues, this field will be 0. When it pushes to RX Destination queues, it will be set based on the constructed descriptor.

CAUTION

A race condition may occur whenever a program writes to two differing memory endpoints, meaning that the memory writes are not guaranteed to land in the order written. When the write to push to a PKTDMA Tx queue immediately follows a write to another endpoint (such as a descriptor or payload data), the PKTDMA could start reading the data before it has actually landed. This can be mitigated by adding an MFENCE instruction prior to the push.