= GIET_VM / MWR Driver =

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The [source:soft/giet_vm/giet_drivers/mwr_driver.c mwr_driver.c] and [source:soft/giet_vm/giet_drivers/mwr_driver.h mwr_driver.h] files define the MWR driver.

The vci_mwmr_dma component is a multi-channels hardware component that can be used to connect an hardware coprocesseur to a VCI interconnect.
This component provides the coprocessor one or several TO_COPROC or FROM_COPROC FIFO type communication channels, without address.
Each T0_COPROC/FROM coproc port contains an hardware FIFO interface (data, r_wok, w_rok signals), plus three signals (REQ, ACK, BURSTS) allowing the coprocessor
to request an integer number of data burst. Each burst contains a fixed number of 32 bits words. Each channel implements two running modes:
 * in '''MWMR''' mode the channel FSM transfer an infinite" stream of data to or from a MWMR software FIFO, implementing the 7 steps MWMR protocol.
 * in '''DMA''' mode the channel FSM transfer a fixed size chunk of data to or from a memory buffer, with a completion signaling interrupt.

It is an ''internal'' peripheral, even if it is not replicated in all clusters. 

WARNING : The MWR driver is not available yet.