GIET-VM / IOB Driver

The iob_driver.c​ and iob_driver.h​ files define the IOB driver.

This vci_io_bridge component is a bridge allowing software to send configuration requests to external peripherals, and allowing external peripherals with a DMA capability to directly access the internal L3 caches (or external memory) without passing through the internal L2 caches. This vci_io_bridge implement an IOMMU using a dedicated IOMMU page table.

This component should be implemented in the cluster specified by the (X_IO / Y_IO) variables in the hard_config.h file, and the physical base address is (cluster_io << 32) | SEG_IOB_BASE. The SEG_IOB_BASE virtual addresses must be defined in hard_config.h file.

The addressables registers map, and the error codes are defined here​.

void _iob_inval_tlb_entry( unsigned int cluster_xy, unsigned int vaddr )

This function invalidates a TLB entry identified by a virtual address, in the IOMMU.

void _iob_set_iommu_ptpr( unsigned int cluster_xy, unsigned int value )

This function sets a new value in IOB_IOMMU_PTPR register.