Fabio Ricciato, Paolo Pellegrino, Maura Turolla, Paolo Gallo Telecom Italia Lab
Franco Fummi Massimo Poncino Università di Verona - Dipartimento di I...
Mission – being a worldwide excellence center for research and realization of innovative ICT products and systems that can be integrated on silicon, merging system and technology know how and creating business opportunities for Telecom Italia • UMTS Terminals and Base Station • ADSL modem e Home Gateway • Network Processor • Intellectual Property libraries(VIPLibrary®) • Virtual Platforms for system simulations and field trails • IC Cards (SIM e Smart cards) • Optical and electro-optical products (i.e. digital wrappers) European SystemC Users Group Meeting
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Networked Embedded Systems • Embedded Systems with communication capabilities – Environmental Monitoring – Mobile Wireless devices – Network Access Point – Domotic application
• Embedded Systems with on chip network – Complex Protocol on SoC bus
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Network simulation capability
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System Level Modeling
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Simulation cores synchronization System Level Modeling
New user objects New objects do not change the behaviour of existing objects •
ports to read data sent by NS2 agents, they are derived by template class sc_in
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agents do not call standard sendv method to send data, but call a kernel function that send data to SystemC
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agents use the standard recv method to receive data from SystemC
– ns_in
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ports to write data to NS2 agents (derived by sc_out) – ns_out
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methods that execute if new data are sent by NS2 agents to SystemC ports.
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– ns_proc
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Communication at the kernel level only 6
Data Exchange Packet Size Packet Type Data time Data Size
Data
Receiver
... Next Event Time
Process Queue Wrapper
NS2 Kernel
Data Queue Manager
Data Queue Manager
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....
Message
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SystemC Kernel
Process Queue Wrapper
Time synchronization • Two communicating processes
write T0
Start phase
through sockets, shared memory, messages... •
read
Symmetric synchronization algorithm
Yes
• The event queues are kept
schedule event
separated
write T kernel1 next event
• Each kernel communicates its next scheduled event All rights reserved
Tkernel2
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T kernel1 < kernel2 T No
write T kernel1
Performance • Messages among kernels are as few as possible • Two types of message: ‘time message’ and ‘data message’. Data message can carries a large amount of data for different receivers to reduce number of messages • Each kernel can inject events into the other’s event queue only if some data have to move across the simulators – When one kernel is running its next event time is lower than the other’s one – Data arriving from the other kernel have been generated earlier than the All rights reserved
next event time of the current kernel
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Intrusion into simulation kernel (SC) •
sc_simcontext – created a new function sc_ns_start that starts the cosimulation – created new methods to run all the processes sensitive to data from NS2 – created methods to register NS2 ports and NS2 processes
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sc_module – defined all the macros for the user to use all the new objects (ns_in, ns_out ns_proc)
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sc_process, sc_process_int – created the class ns_proc for the management of NS2 processes
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ns_port
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– created the new class ns_in to read data sent by NS2 – created the new class ns_out to send data to NS2
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Intrusion into simulation kernel (NS2) •
Scheduler.{c,h} – Modified method Scheduler::run to implement the synchronization algorithm – added method to register objects that need to exchange data with SystemC
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New Agent – socketUDP
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Generic functions for entry point at different protocols levels – socketLink – socketApp
– …
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No performance degradation European SystemC Users Group Meeting
