User manual
Table Of Contents
- Intel® IXP2800 Network Processor
- Copyright
- Contents
- Introduction 1
- Technical Description 2
- 2.1 Overview
- 2.2 Intel XScale® Core Microarchitecture
- 2.3 Microengines
- 2.4 DRAM
- 2.5 SRAM
- 2.6 Scratchpad Memory
- 2.7 Media and Switch Fabric Interface
- 2.8 Hash Unit
- 2.9 PCI Controller
- 2.10 Control and Status Register Access Proxy
- 2.11 Intel XScale® Core Peripherals
- 2.12 I/O Latency
- 2.13 Performance Monitor
- Intel XScale® Core 3
- 3.1 Introduction
- 3.2 Features
- 3.3 Memory Management
- 3.4 Instruction Cache
- 3.5 Branch Target Buffer (BTB)
- 3.6 Data Cache
- 3.6.1 Overviews
- 3.6.2 Data Cache and Mini-Data Cache Operation
- 3.6.3 Data Cache and Mini-Data Cache Control
- 3.6.4 Reconfiguring the Data Cache as Data RAM
- 3.6.5 Write Buffer/Fill Buffer Operation and Control
- 3.7 Configuration
- 3.8 Performance Monitoring
- 3.9 Performance Considerations
- 3.9.1 Interrupt Latency
- 3.9.2 Branch Prediction
- 3.9.3 Addressing Modes
- 3.9.4 Instruction Latencies
- 3.9.4.1 Performance Terms
- 3.9.4.2 Branch Instruction Timings
- 3.9.4.3 Data Processing Instruction Timings
- 3.9.4.4 Multiply Instruction Timings
- 3.9.4.5 Saturated Arithmetic Instructions
- 3.9.4.6 Status Register Access Instructions
- 3.9.4.7 Load/Store Instructions
- 3.9.4.8 Semaphore Instructions
- 3.9.4.9 Coprocessor Instructions
- 3.9.4.10 Miscellaneous Instruction Timing
- 3.9.4.11 Thumb Instructions
- 3.10 Test Features
- 3.11 Intel XScale® Core Gasket Unit
- 3.12 Intel XScale® Core Peripheral Interface
- 3.12.1 XPI Overview
- 3.12.2 UART Overview
- 3.12.3 UART Operation
- 3.12.4 Baud Rate Generator
- 3.12.5 General Purpose I/O (GPIO)
- 3.12.6 Timers
- 3.12.7 Slowport Unit
- Microengines 4
- DRAM 5
- SRAM Interface 6
- SHaC - Unit Expansion 7
- Media and Switch Fabric Interface 8
- 8.1 Overview
- 8.2 Receive
- 8.3 Transmit
- 8.4 RBUF and TBUF Summary
- 8.5 CSIX Flow Control Interface
- 8.6 Deskew and Training
- 8.7 CSIX Startup Sequence
- 8.8 Interface to Command and Push and Pull Buses
- 8.9 Receiver and Transmitter Interoperation with Framers and Switch Fabrics
- 8.9.1 Receiver and Transmitter Configurations
- 8.9.2 System Configurations
- 8.9.2.1 Framer, Single Network Processor Ingress and Egress, and Fabric Interface Chip
- 8.9.2.2 Framer, Dual Network Processor Ingress, Single Network Processor Egress, and Fabric Interface Chip
- 8.9.2.3 Framer, Single Network Processor Ingress and Egress, and CSIX-L1 Chips for Translation and Fabric Interface
- 8.9.2.4 CPU Complex, Network Processor, and Fabric Interface Chip
- 8.9.2.5 Framer, Single Network Processor, Co-Processor, and Fabric Interface Chip
- 8.9.3 SPI-4.2 Support
- 8.9.4 CSIX-L1 Protocol Support
- 8.9.5 Dual Protocol (SPI and CSIX-L1) Support
- 8.9.6 Transmit State Machine
- 8.9.7 Dynamic De-Skew
- 8.9.8 Summary of Receiver and Transmitter Signals
- PCI Unit 9
- 9.1 Overview
- 9.2 PCI Pin Protocol Interface Block
- 9.2.1 PCI Commands
- 9.2.2 IXP2800 Network Processor Initialization
- 9.2.3 PCI Type 0 Configuration Cycles
- 9.2.4 PCI 64-Bit Bus Extension
- 9.2.5 PCI Target Cycles
- 9.2.6 PCI Initiator Transactions
- 9.2.7 PCI Fast Back-to-Back Cycles
- 9.2.8 PCI Retry
- 9.2.9 PCI Disconnect
- 9.2.10 PCI Built-In System Test
- 9.2.11 PCI Central Functions
- 9.3 Slave Interface Block
- 9.4 Master Interface Block
- 9.5 PCI Unit Error Behavior
- 9.5.1 PCI Target Error Behavior
- 9.5.1.1 Target Access Has an Address Parity Error
- 9.5.1.2 Initiator Asserts PCI_PERR_L in Response to One of Our Data Phases
- 9.5.1.3 Discard Timer Expires on a Target Read
- 9.5.1.4 Target Access to the PCI_CSR_BAR Space Has Illegal Byte Enables
- 9.5.1.5 Target Write Access Receives Bad Parity PCI_PAR with the Data
- 9.5.1.6 SRAM Responds with a Memory Error on One or More Data Phases on a Target Read
- 9.5.1.7 DRAM Responds with a Memory Error on One or More Data Phases on a Target Read
- 9.5.2 As a PCI Initiator During a DMA Transfer
- 9.5.2.1 DMA Read from DRAM (Memory-to-PCI Transaction) Gets a Memory Error
- 9.5.2.2 DMA Read from SRAM (Descriptor Read) Gets a Memory Error
- 9.5.2.3 DMA from DRAM Transfer (Write to PCI) Receives PCI_PERR_L on PCI Bus
- 9.5.2.4 DMA To DRAM (Read from PCI) Has Bad Data Parity
- 9.5.2.5 DMA Transfer Experiences a Master Abort (Time-Out) on PCI
- 9.5.2.6 DMA Transfer Receives a Target Abort Response During a Data Phase
- 9.5.2.7 DMA Descriptor Has a 0x0 Word Count (Not an Error)
- 9.5.3 As a PCI Initiator During a Direct Access from the Intel XScale® Core or Microengine
- 9.5.3.1 Master Transfer Experiences a Master Abort (Time-Out) on PCI
- 9.5.3.2 Master Transfer Receives a Target Abort Response During a Data Phase
- 9.5.3.3 Master from the Intel XScale® Core or Microengine Transfer (Write to PCI) Receives PCI_PERR_L on PCI Bus
- 9.5.3.4 Master Read from PCI (Read from PCI) Has Bad Data Parity
- 9.5.3.5 Master Transfer Receives PCI_SERR_L from the PCI Bus
- 9.5.3.6 Intel XScale® Core Microengine Requests Direct Transfer when the PCI Bus is in Reset
- 9.5.1 PCI Target Error Behavior
- 9.6 PCI Data Byte Lane Alignment
- Clocks and Reset 10
- 10.1 Clocks
- 10.2 Synchronization Between Frequency Domains
- 10.3 Reset
- 10.4 Boot Mode
- 10.5 Initialization
- Performance Monitor Unit 11
- 11.1 Introduction
- 11.2 Interface and CSR Description
- 11.3 Performance Measurements
- 11.4 Events Monitored in Hardware
- 11.4.1 Queue Statistics Events
- 11.4.2 Count Events
- 11.4.3 Design Block Select Definitions
- 11.4.4 Null Event
- 11.4.5 Threshold Events
- 11.4.6 External Input Events
- 11.4.6.1 XPI Events Target ID(000001) / Design Block #(0100)
- 11.4.6.2 SHaC Events Target ID(000010) / Design Block #(0101)
- 11.4.6.3 IXP2800 Network Processor MSF Events Target ID(000011) / Design Block #(0110)
- 11.4.6.4 Intel XScale® Core Events Target ID(000100) / Design Block #(0111)
- 11.4.6.5 PCI Events Target ID(000101) / Design Block #(1000)
- 11.4.6.6 ME00 Events Target ID(100000) / Design Block #(1001)
- 11.4.6.7 ME01 Events Target ID(100001) / Design Block #(1001)
- 11.4.6.8 ME02 Events Target ID(100010) / Design Block #(1001)
- 11.4.6.9 ME03 Events Target ID(100011) / Design Block #(1001)
- 11.4.6.10 ME04 Events Target ID(100100) / Design Block #(1001)
- 11.4.6.11 ME05 Events Target ID(100101) / Design Block #(1001)
- 11.4.6.12 ME06 Events Target ID(100110) / Design Block #(1001)
- 11.4.6.13 ME07 Events Target ID(100111) / Design Block #(1001)
- 11.4.6.14 ME10 Events Target ID(110000) / Design Block #(1010)
- 11.4.6.15 ME11 Events Target ID(110001) / Design Block #(1010)
- 11.4.6.16 ME12 Events Target ID(110010) / Design Block #(1010)
- 11.4.6.17 ME13 Events Target ID(110011) / Design Block #(1010)
- 11.4.6.18 ME14 Events Target ID(110100) / Design Block #(1010)
- 11.4.6.19 ME15 Events Target ID(110101) / Design Block #(1010)
- 11.4.6.20 ME16 Events Target ID(100110) / Design Block #(1010)
- 11.4.6.21 ME17 Events Target ID(110111) / Design Block #(1010)
- 11.4.6.22 SRAM DP1 Events Target ID(001001) / Design Block #(0010)
- 11.4.6.23 SRAM DP0 Events Target ID(001010) / Design Block #(0010)
- 11.4.6.24 SRAM CH3 Events Target ID(001011) / Design Block #(0010)
- 11.4.6.25 SRAM CH2 Events Target ID(001100) / Design Block #(0010)
- 11.4.6.26 SRAM CH1 Events Target ID(001101) / Design Block #(0010)
- 11.4.6.27 SRAM CH0 Events Target ID(001110) / Design Block #(0010)
- 11.4.6.28 DRAM DPLA Events Target ID(010010) / Design Block #(0011)
- 11.4.6.29 DRAM DPSA Events Target ID(010011) / Design Block #(0011)
- 11.4.6.30 IXP2800 Network Processor DRAM CH2 Events Target ID(010100) / Design Block #(0011)
- 11.4.6.31 IXP2800 Network Processor DRAM CH1 Events Target ID(010101) / Design Block #(0011)
- 11.4.6.32 IXP2800 Network Processor DRAM CH0 Events Target ID(010110) / Design Block #(0011)
Hardware Reference Manual 51
Intel
®
IXP2800 Network Processor
Technical Description
2.4.2 Read and Write Access
The minimum DRAM physical access length is 16 bytes. Software (and PCI) can read or write as
little as a single byte, however the time (and bandwidth) taken at the DRAMs is the same as for an
access of 16 bytes. Therefore, the best utilization of DRAM bandwidth will be for accesses that are
multiples of 16 bytes.
If ECC is enabled, writes of less than 8 bytes must do read-modify-writes, which take two 16-byte
time accesses (one for the read and one for the write).
2.5 SRAM
The IXP2800 Network Processor has four independent SRAM controllers, which each support
pipelined QDR synchronous static RAM (SRAM) and/or a coprocessor that adheres to QDR
signaling. Any or all controllers can be left unpopulated if the application does not need to use
them. SRAM are accessible by the Microengines, the Intel XScale
®
core, and the PCI Unit
(external bus masters and DMA).
The memory is logically four bytes (32-bits) wide; physically the data pins are two bytes wide and
are double clocked. Byte parity is supported. Each of the four bytes has a parity bit, which is
written when the byte is written and checked when the data is read. There are byte-enables that
select which bytes to write for writes of less than 32 bits.
Each of the 4 QDR ports are QDR and QDRII compatible. Each port implements the “_K” and
“_C” output clocks and “_CQ” as an input and their inversions. (Note: the “_C” and “_CQ” clocks
are optional). Extensive work has been performed providing impedance controls within the
IXP2800 Network Processor for processor-initiated signals driving to QDR parts. Providing a
clean signaling environment is critical to achieving 200 – 250 MHz QDRII data transfers.
The configuration assumptions for the IXP2800 Network Processor I/O driver/receiver
development includes four QDR loads and the IXP2800 Network Processor. The IXP2800
Network Processor supports bursts of two SRAMs, but does not support bursts of four SRAMs.
The SRAM controller can also be configured to interface to an external coprocessor that adheres to
the QDR electricals and protocol. Each SRAM controller may also interface to an external
coprocessor through its standard QDR interface. This interface enables the cohabitation of both
SRAM devices and coprocessors to operate on the same bus. The coprocessor behaves as a
memory-mapped device on the SRAM bus.