General rules for the SoCLib hardware components

A) Naming conventions

namespaces

SystemC being build upon C++, we use the C++ namespace constructs, to create unambiguous names. SoCLib defines the following namespaces:

• soclib
• soclib::common
• soclib::caba *soclib::tlmt

variables

The following conventions have been defined :

• All component port names should be prefixed with p_
• All component register names should be prefixed with r_
• All component member variable names should be prefixed with m_

B) VCI initiators and targets indexation

In a VCI-based architecture, all initiators and targets must be indexed. Initiators and targets have different address spaces.

• The target index is used by interconnect components : those components decode the VCI address MSB bits to get the target index and route the VCI command packets.
• The initiator index is used by the interconnect components to route the VCI response packets : the initiator index is the VCI SRCID value.

Indexes can be :

• a simple scalar index, in case of a flat interconnect.
• a composite index, in case of a clusterised architecture, using a two level hierarchical interconnect. Each component is identified by two scalars: cluster_index, local_index.

The common/int_tab.hfile defines an utility class storing a list of indexes : All indexes must be declared as IntTabs.

C) Endianness

All SoCLib targets components respect the little-endianness convention. In case of write, the bytes transfers are fully controlled by the VCI BE bits :

• If the VCI word is larger than one byte, the LSB bits of the VCI ADDRESS are ignored, and the VCI ADDRESS is only used to address the selected VCI word.
• the selected bytes are specified the VCI BE field, and the BE0 bit is always associated to the Byte 0 of the VCI WDATA field.