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

3.1 Host Packet Descriptor

Host packet descriptors are designed to be used when the application requires support for true, unlimited fragment count scatter / gather-type operations. The host packet descriptor contains the following information:

  • Indicator that identifies the descriptor as a host packet descriptor
  • Source and destination tags
  • Packet type
  • Packet length
  • Protocol-specific region size
  • Protocol-specific control / status bits
  • Pointer to the first valid byte in the SOP data buffer
  • Length of the SOP data buffer
  • Pointer to the next buffer descriptor in the packet
  • Software-specific information

Host packet descriptors always contain 32 bytes of required information and may also contain optional software-specific information and protocol-specific information. How much optional information (and therefore the allocated size of the descriptors) is required is application-dependent. The descriptor layout is shown in Table 3-1.

Table 3-1 Host Packet Descriptor Layout

Packet info (12 bytes)
Buffer info (8 bytes)
Linking info (4 bytes)
Original buffer info
(8 bytes)
Extended packet info block (optional)
Includes timestamp and software data (16 bytes)
Protocol-specific data (optional)
(0 to M bytes where M is a multiple of 4)
Other SW data (optional and user defined)
Packet info
(12 bytes)
Buffer info (8 bytes)
Linking info
(4 bytes)
Original buffer info
(8 bytes)
Extended packet info block (optional)
Includes timestamp and software data (16 bytes)
Protocol-specific data (optional)
(0 to M bytes where M is a multiple of 4)
Other SW data (optional and user defined)

Host packet descriptors may be linked with zero or more additional host buffer descriptors in a singly-linked-list fashion to form packets. Each host packet consists of a single host packet descriptor followed by a chain of zero or more host buffer descriptors linked together using the next descriptor pointer fields in the descriptors. The last descriptor in a host packet has a 0 next descriptor pointer.

The other SW data portion of the descriptor exists after all of the defined words and is reserved for use by the host software to store completely private data. This region is not used in any way by the DMA or queue manager modules in a Multicore Navigator system and these modules will not modify any bytes within this region.

The contents of the host packet descriptor words are detailed in the following tables:

Table 3-2 Host Packet Descriptor Packet Information Word 0 (PD Word 0)

Bits Name Description RX Overwrite
31-30 Packet Id Host packet descriptor type identifier. Value is always 0 (0x0) for Host Packet descriptors. Yes
29-25 Packet Type This field indicates the type of this packet and is encoded as follows:

0-31 = To Be Assigned

 Yes
24-23 Reserved Unused Yes
22 Protocol Specific Region Location This field indicates the location of the protocol-specific words:
  • 0 = PS words are located in the descriptor
  • 1 = PS words are located in the SOP Buffer immediately prior to the data.
 Yes
21-0 Packet Length The length of the packet data in bytes. If the packet length is less than the sum of the buffer lengths, then the packet data will be truncated. A packet length greater than the sum of the buffers is an error. The valid range for the packet length is 0 to 4M-1 bytes. If the packet length is set to 0, the port will not actually transmit any information. Instead, the port will perform buffer / descriptor reclamation as instructed in the return information in word 2. Yes

Table 3-3 Host Packet Descriptor Packet Information Word 1 (PD Word 1)

Bits Name Description RX Overwrite
31-24 Source Tag - Hi This field is application-specific. During packet reception, the DMA controller in the port will overwrite this field as specified in the RX_SRC_TAG_HI_SEL field in the flow configuration table entry. Configurable
23-16 Source Tag - Lo This field is application-specific. During packet reception, the DMA controller in the port will overwrite this field as specified in the RX_SRC_TAG_LO_SEL field in the flow configuration table entry. For TX, this value supplies the RX flow index to the Streaming I/F for infrastructure use. Configurable
15-8 Dest Tag – Hi This field is application specific. During packet reception, the DMA controller in the port will overwrite this field as specified in the RX_DEST_TAG_HI_SEL field in the flow configuration table entry. Configurable
7-0 Dest Tag - Lo This field is application specific. During packet reception, the DMA controller in the port will overwrite this field as specified in the RX_DEST_TAG_LO_SEL field in the flow configuration table entry. Configurable

Table 3-4 Host Packet Descriptor Packet Information Word 2 (PD Word 2)

Bits Name Description RX Overwrite
31 Extended Packet Info Block Present This field indicates the presence of the extended packet info block in the descriptor.
  • 0 = EPIB is not present
  • 1 = 16 byte EPIB is present
 Yes
30 Reserved Unused Yes
29-24 Protocol Specific Valid Word Count This field indicates the valid # of 32-bit words in the protocol-specific region. This is encoded in increments of 4 bytes as follows:
  • 0 = 0 bytes
  • 1 = 4 bytes

…

  • 16 = 64 bytes

…

32 = 128 bytes

33-63 = Reserved

 Yes
23-20 Error Flags This field contains error flags that can be assigned based on the packet type Yes
19-16 Protocol Specific Flags This field contains protocol-specific flags / information that can be assigned based on the packet type. Yes
15 Return Policy
  • This field indicates the return policy for this packet.
  • 0 = Entire packet (still linked together) should be returned to queue specified in bits 13-0 below.
  • 1 = Each buffer should be returned to queue specified in bits 13-0 of Word 2 in their respective descriptors. The TX DMA will return each buffer in sequence.
 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. The value 0xFFF is reserved. No

Table 3-5 Host Packet Descriptor Buffer 0 Info Word 0 (PD Word 3)

Bits Name Description RX Overwrite
31-22 Reserved Unused Yes
21-0 Buffer 0 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 3-6 Host Packet Descriptor Buffer 0 Info Word 1 (PD Word 4)

Bits Name Description RX Overwrite
31-0 Buffer 0 Pointer The buffer pointer is the byte-aligned memory address of the buffer associated with the buffer descriptor. This value will be written during reception. If the protocol-specific words are placed at the beginning of the SOP buffer, this pointer will point to the PS words. The offset to the data in that case must be calculated by the consumer using the protocol-specific valid word count from word 2. Usage note: For TX, it is a good practice to initialize this field and the Original Ptr field in word 7 with the actual buffer address, but this is the field that is used. For RX, this field may be left uninitialized, or set to 0. Yes

Table 3-7 Host Packet Descriptor Linking Word (PD 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. If the value of this pointer is 0, then the current buffer is the last buffer in the packet. The host sets the next descriptor pointer. Yes

Table 3-8 Host Packet Descriptor Original Buffer Info Word 0 (PD 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.

Usage Note: It is good practice to always set this field during initialization.

 No

Table 3-9 Host Packet Descriptor Original Buffer Info Word 1 (PD 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.

Usage Note: It is good practice to always set this field during initialization, but is used only in RX.

 No

Table 3-10 Host Packet Descriptor Extended Packet Info Block Word 0 (Optional) (1)

Bits Name Description RX Overwrite
31-0 Timestamp Info This field contains an application-specific timestamp that can be used for traffic shaping in a QoS enabled system. Configurable
(1) This word is present only if the extended packet info block present bit is set in word 2.

Table 3-11 Host Packet Descriptor Extended Packet Info Block Word 1 (Optional) (1)

Bits Name Description RX Overwrite
31-0 Software Info 0 This field stores software-centric information that needs to travel with the packet through the stack. This information will be copied from the source descriptor to the destination descriptor whenever a prefetch operation is performed or when transferring through an infrastructure DMA node. Configurable
(1) This word is present only if the Extended Packet Info Block present bit is set in Word 2.

Table 3-12 Host Packet Descriptor Extended Packet Info Block Word 2 (Optional) (1)

Bits Name Description RX Overwrite
31-0 Software Info 1 This field stores software centric information that needs to travel with the packet through the stack. This information will be copied from the source descriptor to the destination descriptor whenever a prefetch operation is performed or when transferring through an infrastructure DMA node. Configurable
(1) This word is present only if the Extended Packet Info Block present bit is set in Word 2.

Table 3-13 Host Packet Descriptor Extended Packet Info Block Word 3 (Optional) (1)

Bits Name Description RX Overwrite
31-0 Software Info 2 This field stores software centric information that needs to travel with the packet through the stack. This information will be copied from the source descriptor to the destination descriptor whenever a prefetch operation is performed or when transferring through an infrastructure DMA node. Configurable
(1) This word is present only if the Extended Packet Info Block present bit is set in Word 2.

Table 3-14 Host Packet Descriptor Protocol Specific Word N (Optional)

Bits Name Description RX Overwrite
31-0 Protocol Specific Data N This field stores information that varies depending on the block and packet type. Configurable