Skip to content

Latest commit

 

History

History
56 lines (43 loc) · 5.65 KB

interfaces.md

File metadata and controls

56 lines (43 loc) · 5.65 KB

Hardware Interfaces

Referring to the Comportable guideline for peripheral device functionality, the module i2c has the following hardware interfaces defined

  • Primary Clock: clk_i
  • Other Clocks: none
  • Bus Device Interfaces (TL-UL): tl
  • Bus Host Interfaces (TL-UL): none

Peripheral Pins for Chip IO

Pin name Direction Description
sda inout Serial input data bit
scl inout Serial input clock bit
Port Name Package::Struct Type Act Width Description
tl tlul_pkg::tl req_rsp rsp 1

Interrupts

Interrupt Name Type Description
fmt_threshold Event host mode interrupt: raised when the FMT FIFO depth is less than the low threshold.
rx_threshold Event host mode interrupt: raised if the RX FIFO is greater than the high threshold.
fmt_overflow Event host mode interrupt: raised if the FMT FIFO has overflowed.
rx_overflow Event host mode interrupt: raised if the RX FIFO has overflowed.
nak Event host mode interrupt: raised if there is no ACK in response to an address or data write
scl_interference Event host mode interrupt: raised if the SCL line drops early (not supported without clock synchronization).
sda_interference Event host mode interrupt: raised if the SDA line goes low when host is trying to assert high
stretch_timeout Event host mode interrupt: raised if target stretches the clock beyond the allowed timeout period
sda_unstable Event host mode interrupt: raised if the target does not assert a constant value of SDA during transmission.
cmd_complete Event host and target mode interrupt. In host mode, raised if the host issues a repeated START or terminates the transaction by issuing STOP. In target mode, raised if the external host issues a STOP or repeated START.
tx_stretch Status target mode interrupt: raised if the target is stretching clocks for a read command. This is a level status interrupt.
tx_overflow Event target mode interrupt: raised if TX FIFO has overflowed.
acq_full Status target mode interrupt: raised if ACQ FIFO becomes full. This is a level status interrupt.
unexp_stop Event target mode interrupt: raised if STOP is received without a preceding NACK during an external host read.
host_timeout Event target mode interrupt: raised if the host stops sending the clock during an ongoing transaction.

Security Alerts

Alert Name Description
fatal_fault This fatal alert is triggered when a fatal TL-UL bus integrity fault is detected.

Security Countermeasures

Countermeasure ID Description
I2C.BUS.INTEGRITY End-to-end bus integrity scheme.