Entity: otp_ctrl_kdi

• File: otp_ctrl_kdi.sv

Diagram

Description

Ports

Port name	Direction	Type	Description
clk_i	input
rst_ni	input
kdi_en_i	input		Pulse to enable this module after OTP partitions have been initialized.
escalate_en_i	input		Escalation input. This moves the FSM into a terminal state.
fsm_err_o	output		FSM is in error state
scrmbl_key_seed_valid_i	input		Key seed inputs from OTP
flash_data_key_seed_i	input	[FlashKeySeedWidth-1:0]
flash_addr_key_seed_i	input	[FlashKeySeedWidth-1:0]
sram_data_key_seed_i	input	[SramKeySeedWidth-1:0]
edn_req_o	output		EDN interface for requesting entropy
edn_ack_i	input
edn_data_i	input	[EdnDataWidth-1:0]
flash_otp_key_i	input	flash_otp_key_req_t	Scrambling key requests
flash_otp_key_o	output	flash_otp_key_rsp_t
sram_otp_key_i	input	[NumSramKeyReqSlots-1:0]
sram_otp_key_o	output	[NumSramKeyReqSlots-1:0]
otbn_otp_key_i	input	otbn_otp_key_req_t
otbn_otp_key_o	output	otbn_otp_key_rsp_t
scrmbl_mtx_req_o	output		Scrambling mutex request
scrmbl_mtx_gnt_i	input
scrmbl_cmd_o	output	otp_scrmbl_cmd_e	Scrambling datapath interface
scrmbl_mode_o	output	digest_mode_e
scrmbl_sel_o	output	[ConstSelWidth-1:0]
scrmbl_data_o	output	[ScrmblBlockWidth-1:0]
scrmbl_valid_o	output
scrmbl_ready_i	input
scrmbl_valid_i	input
scrmbl_data_i	input	[ScrmblBlockWidth-1:0]

Signals

Name	Type	Description
req	logic [NumReq-1:0]
gnt	logic [NumReq-1:0]
req_bundles	req_bundle_t
req_valid	logic	This arbitrates among incoming key derivation requests on a round robin basis to prevent deadlock.
req_ready	logic	This arbitrates among incoming key derivation requests on a round robin basis to prevent deadlock.
req_bundle	req_bundle_t
seed_cnt_clr	logic	//////////////////////////// Temporary Regs and Muxes // ////////////////////////////
seed_cnt_en	logic	//////////////////////////// Temporary Regs and Muxes // ////////////////////////////
entropy_cnt_clr	logic	//////////////////////////// Temporary Regs and Muxes // ////////////////////////////
entropy_cnt_en	logic	//////////////////////////// Temporary Regs and Muxes // ////////////////////////////
seed_cnt_d	logic [1:0]
seed_cnt_q	logic [1:0]
entropy_cnt_d	logic [1:0]
entropy_cnt_q	logic [1:0]
seed_valid_reg_en	logic
key_reg_en	logic
nonce_reg_en	logic
seed_valid_d	logic
seed_valid_q	logic
key_out_d	logic [ScrmblKeyWidth/ScrmblBlockWidth-1:0][ScrmblBlockWidth-1:0]
key_out_q	logic [ScrmblKeyWidth/ScrmblBlockWidth-1:0][ScrmblBlockWidth-1:0]
nonce_out_d	logic [NumNonceChunks-1:0][ScrmblBlockWidth-1:0]
nonce_out_q	logic [NumNonceChunks-1:0][ScrmblBlockWidth-1:0]
data_sel	data_sel_e	Select correct 64bit block.
state_d	state_e
state_q	state_e
edn_req_d	logic
edn_req_q	logic
state_raw_q	logic [StateWidth-1:0]	///////////// Registers // ///////////// This primitive is used to place a size-only constraint on the flops in order to prevent FSM state encoding optimizations.

Constants

Name	Type	Value	Description
NumReq	int	3 + NumSramKeyReqSlots	////////////////////// Integration Checks // ////////////////////// 2xFlash, OTBN + SRAM slots
OtbnNonceSel	int	OtbnNonceWidth / ScrmblBlockWidth
FlashNonceSel	int	FlashKeyWidth / ScrmblBlockWidth
SramNonceSel	int	SramNonceWidth / ScrmblBlockWidth
StateWidth	int	10	/////////////// Control FSM // /////////////// Encoding generated with: $ ./sparse-fsm-encode.py -d 5 -m 11 -n 10 \ -s 2544133835 --language=sv Hamming distance histogram: 0: -- 1: -- 2: -- 3: -- 4: -- 5:

Types

Name	Type	Description
req_bundle_t	struct packed { logic ingest_entropy; logic chained_digest; digest_sel_e digest_sel; logic fetch_nonce; logic [1:0] nonce_size; logic seed_valid; logic [3:0][ScrmblBlockWidth-1:0] seed; }	///////////////////////////////// Input Mapping and Arbitration // ///////////////////////////////// The key derivation and token hashing functions are aligned such that 2 x 128bit key seeds / token blocks are processed in two subsequent steps using the digest primitive. This effectively compresses these blocks down into 2 x 64bit blocks, thereby creating one 128bit key or token output. The same FSM is shared among the different flavors of key derivation and token hashing functions, and the following configuration options are available: 1) ingest an additional 128bit entropy block after ingesting a 128bit key seed. 2) keep digest state after producing the first 64bit block instead of reverting to the IV. 3) netlist constant index. 4) fetch additional entropy for the nonce output. 5) whether or not the key seed is valid. if not, it will be defaulted to '0. 6) 256bit key seed / token input. The configuration options are set further below, depending on the request type.
data_sel_e	enum logic { SeedData, EntropyData }
state_e	enum logic [StateWidth-1:0] { ResetSt = 10'b0111100000, IdleSt = 10'b0001111101, DigClrSt = 10'b1101101011, DigLoadSt = 10'b0100011010, FetchEntropySt = 10'b0010001001, DigEntropySt = 10'b0110110111, DigFinSt = 10'b0001000110, DigWaitSt = 10'b1100000101, FetchNonceSt = 10'b1010101110, FinishSt = 10'b1111011100, ErrorSt = 10'b1011010011 }

Processes

• p_outregs: ( )

• p_fsm: ( )

• p_regs: ( @(posedge clk_i or negedge rst_ni) )

Instantiations

• u_state_regs: prim_flop