TSEC (Tegra Security Co-processor) is a dedicated unit powered by a NVIDIA Falcon microprocessor with crypto extensions.

Driver

A host driver for communicating with the TSEC is mapped to physical address 0x54500000 with a total size of 0x40000 bytes and exposes several registers.

Registers

Registers from 0x54500000 to 0x54501000 are used to configure the host interface (HOST1X).

Registers from 0x54501000 to 0x54502000 are a MMIO window for communicating with the Falcon microprocessor. From this range, the subset of registers from 0x54501400 to 0x54501FE8 are specific to the TSEC and are subdivided into:

  • 0x54501400 to 0x54501500: SCP (Secure Crypto Processor?).
  • 0x54501500 to 0x54501600: TRNG (True Random Number Generator).
  • 0x54501600 to 0x54501700: TFBIF (Tegra Framebuffer Interface).
  • 0x54501700 to 0x54501800: DMA.
  • 0x54501800 to 0x54501900: TEGRA (miscellaneous interfaces).
Name Address Width
TSEC_THI_INCR_SYNCPT 0x54500000 0x04
TSEC_THI_INCR_SYNCPT_ERR 0x54500008 0x04
TSEC_THI_CTXSW_INCR_SYNCPT 0x5450000C 0x04
TSEC_THI_CTXSW 0x54500020 0x04
TSEC_THI_CONT_SYNCPT_EOF 0x54500028 0x04
TSEC_THI_METHOD0 0x54500040 0x04
TSEC_THI_METHOD1 0x54500044 0x04
TSEC_THI_INT_STATUS 0x54500078 0x04
TSEC_THI_INT_MASK 0x5450007C 0x04
TSEC_THI_SLCG_STATUS 0x54500084 0x04
TSEC_THI_SLCG_OVERRIDE_HIGH_A 0x54500088 0x04
TSEC_THI_SLCG_OVERRIDE_LOW_A 0x5450008C 0x04
TSEC_THI_CLK_OVERRIDE 0x54500E00 0x04
FALCON_IRQSSET 0x54501000 0x04
FALCON_IRQSCLR 0x54501004 0x04
FALCON_IRQSTAT 0x54501008 0x04
FALCON_IRQMODE 0x5450100C 0x04
FALCON_IRQMSET 0x54501010 0x04
FALCON_IRQMCLR 0x54501014 0x04
FALCON_IRQMASK 0x54501018 0x04
FALCON_IRQDEST 0x5450101C 0x04
FALCON_GPTMR_PERIOD 0x54501020 0x04
FALCON_GPTMR_TIME 0x54501024 0x04
FALCON_GPTMR_ENABLE 0x54501028 0x04
FALCON_TIME_LOW 0x5450102C 0x04
FALCON_TIME_HIGH 0x54501030 0x04
FALCON_WDTMR_TIME 0x54501034 0x04
FALCON_WDTMR_ENABLE 0x54501038 0x04
FALCON_SCRATCH0 0x54501040 0x04
FALCON_SCRATCH1 0x54501044 0x04
FALCON_ITFEN 0x54501048 0x04
FALCON_IDLESTATE 0x5450104C 0x04
FALCON_CURCTX 0x54501050 0x04
FALCON_NXTCTX 0x54501054 0x04
FALCON_CMDCTX 0x54501058 0x04
FALCON_STATUS_MASK 0x5450105C 0x04
FALCON_VM_SUPERVISOR 0x54501060 0x04
FALCON_MTHD_DATA 0x54501064 0x04
FALCON_MTHD_CMD 0x54501068 0x04
FALCON_MTHD_DATA_WR 0x5450106C 0x04
FALCON_MTHD_OCCUPIED 0x54501070 0x04
FALCON_MTHD_ACK 0x54501074 0x04
FALCON_MTHD_LIMIT 0x54501078 0x04
FALCON_SUBENGINE_RESET 0x5450107C 0x04
FALCON_SCRATCH2 0x54501080 0x04
FALCON_SCRATCH3 0x54501084 0x04
FALCON_PM_TRIGGER 0x54501088 0x04
FALCON_PM_MODE 0x5450108C 0x04
FALCON_DEBUG1 0x54501090 0x04
FALCON_DEBUGINFO 0x54501094 0x04
FALCON_BREAKPOINT0 0x54501098 0x04
FALCON_BREAKPOINT1 0x5450109C 0x04
FALCON_CGCTL 0x545010A0 0x04
FALCON_ENGCTL 0x545010A4 0x04
FALCON_PM_SEL 0x545010A8 0x04
FALCON_HOST_IO_INDEX 0x545010AC 0x04
FALCON_EXCI 0x545010D0 0x04
FALCON_CPUCTL 0x54501100 0x04
FALCON_BOOTVEC 0x54501104 0x04
FALCON_HWCFG 0x54501108 0x04
FALCON_DMACTL 0x5450110C 0x04
FALCON_DMATRF_EXTBASE 0x54501110 0x04
FALCON_DMATRF_VOFF 0x54501114 0x04
FALCON_DMATRFCMD 0x54501118 0x04
FALCON_DMATRF_POFF 0x5450111C 0x04
FALCON_DMATRFSTAT 0x54501120 0x04
FALCON_CRYPTTRFSTAT 0x54501124 0x04
FALCON_CPUSTAT 0x54501128 0x04
FALCON_HWCFG2 0x5450112C 0x04
FALCON_CPUCTL_ALIAS 0x54501130 0x04
FALCON_TLB_CMD 0x54501140 0x04
FALCON_TLB_CMD_RES 0x54501144 0x04
FALCON_BRANCH_HISTORY_CTRL 0x54501148 0x04
FALCON_BRANCH_HISTORY_PC 0x5450114C 0x04
FALCON_IMFILLRNG0 0x54501150 0x04
FALCON_IMFILLRNG1 0x54501154 0x04
FALCON_IMFILLCTL 0x54501158 0x04
FALCON_EXTERRWIN 0x54501160 0x04
FALCON_EXTERRCFG 0x54501164 0x04
FALCON_EXTERRADDR 0x54501168 0x04
FALCON_EXTERRSTAT 0x5450116C 0x04
FALCON_CG2 0x5450117C 0x04
FALCON_CODE_INDEX 0x54501180 0x04
FALCON_CODE 0x54501184 0x04
FALCON_CODE_VIRT_ADDR 0x54501188 0x04
FALCON_DATA_INDEX0 0x545011C0 0x04
FALCON_DATA0 0x545011C4 0x04
FALCON_DATA_INDEX1 0x545011C8 0x04
FALCON_DATA1 0x545011CC 0x04
FALCON_DATA_INDEX2 0x545011D0 0x04
FALCON_DATA2 0x545011D4 0x04
FALCON_DATA_INDEX3 0x545011D8 0x04
FALCON_DATA3 0x545011DC 0x04
FALCON_DATA_INDEX4 0x545011E0 0x04
FALCON_DATA4 0x545011E4 0x04
FALCON_DATA_INDEX5 0x545011E8 0x04
FALCON_DATA5 0x545011EC 0x04
FALCON_DATA_INDEX6 0x545011F0 0x04
FALCON_DATA6 0x545011F4 0x04
FALCON_DATA_INDEX7 0x545011F8 0x04
FALCON_DATA7 0x545011FC 0x04
FALCON_ICD_CMD 0x54501200 0x04
FALCON_ICD_ADDR 0x54501204 0x04
FALCON_ICD_WDATA 0x54501208 0x04
FALCON_ICD_RDATA 0x5450120C 0x04
FALCON_SCTL 0x54501240 0x04
TSEC_SCP_CTL_ACCESS 0x54501400 0x04
TSEC_SCP_CTL_TRNG 0x54501404 0x04
TSEC_SCP_CTL_STAT 0x54501408 0x04
TSEC_SCP_CTL_MODE 0x5450140C 0x04
TSEC_SCP_UNK0 0x54501410 0x04
TSEC_SCP_CTL_PKEY 0x54501418 0x04
TSEC_SCP_SEQ0_STAT 0x54501420 0x04
TSEC_SCP_SEQ_STAT 0x54501428 0x04
TSEC_SCP_INSN_STAT 0x54501430 0x04
TSEC_SCP_UNK2 0x54501454 0x04
TSEC_SCP_AES_STAT 0x54501458 0x04
TSEC_SCP_UNK3 0x54501470 0x04
TSEC_SCP_IRQSTAT 0x54501480 0x04
TSEC_SCP_IRQMASK 0x54501484 0x04
TSEC_SCP_UNK4 0x54501490 0x04
TSEC_SCP_ERR 0x54501498 0x04
TSEC_TRNG_CLKDIV 0x54501500 0x04
TSEC_TRNG_UNK0 0x54501504 0x04
TSEC_TRNG_UNK1 0x5450150C 0x04
TSEC_TRNG_UNK2 0x54501510 0x04
TSEC_TRNG_UNK3 0x54501514 0x04
TSEC_TRNG_UNK4 0x54501518 0x04
TSEC_TRNG_UNK5 0x5450151C 0x04
TSEC_TRNG_UNK6 0x54501528 0x04
TSEC_TRNG_UNK7 0x5450152C 0x04
TSEC_TFBIF_UNK0 0x54501600 0x04
TSEC_TFBIF_MCCIF_FIFOCTRL 0x54501604 0x04
TSEC_TFBIF_UNK1 0x54501608 0x04
TSEC_TFBIF_UNK2 0x5450160C 0x04
TSEC_TFBIF_UNK3 0x54501630 0x04
TSEC_TFBIF_MCCIF_FIFOCTRL1 0x54501634 0x04
TSEC_TFBIF_UNK4 0x54501640 0x04
TSEC_TFBIF_UNK5 0x54501644 0x04
TSEC_TFBIF_UNK6 0x54501648 0x04
TSEC_DMA_CMD 0x54501700 0x04
TSEC_DMA_ADDR 0x54501704 0x04
TSEC_DMA_VAL 0x54501708 0x04
TSEC_DMA_UNK 0x5450170C 0x04
TSEC_TEGRA_FALCON_IP_VER 0x54501800 0x04
TSEC_TEGRA_UNK0 0x54501824 0x04
TSEC_TEGRA_UNK1 0x54501828 0x04
TSEC_TEGRA_UNK2 0x5450182C 0x04
TSEC_TEGRA_CTL 0x54501838 0x04

TSEC_THI_METHOD0

ID Method
0x200 SET_APPLICATION_ID
0x300 EXECUTE
0x500 HDCP_INIT
0x504 HDCP_CREATE_SESSION
0x508 HDCP_VERIFY_CERT_RX
0x50C HDCP_GENERATE_EKM
0x510 HDCP_REVOCATION_CHECK
0x514 HDCP_VERIFY_HPRIME
0x518 HDCP_ENCRYPT_PAIRING_INFO
0x51C HDCP_DECRYPT_PAIRING_INFO
0x520 HDCP_UPDATE_SESSION
0x524 HDCP_GENERATE_LC_INIT
0x528 HDCP_VERIFY_LPRIME
0x52C HDCP_GENERATE_SKE_INIT
0x530 HDCP_VERIFY_VPRIME
0x534 HDCP_ENCRYPTION_RUN_CTRL
0x538 HDCP_SESSION_CTRL
0x53C HDCP_COMPUTE_SPRIME
0x540 HDCP_GET_CERT_RX
0x544 HDCP_EXCHANGE_INFO
0x548 HDCP_DECRYPT_KM
0x54C HDCP_GET_HPRIME
0x550 HDCP_GENERATE_EKH_KM
0x554 HDCP_VERIFY_RTT_CHALLENGE
0x558 HDCP_GET_LPRIME
0x55C HDCP_DECRYPT_KS
0x560 HDCP_DECRYPT
0x564 HDCP_GET_RRX
0x568 HDCP_DECRYPT_REENCRYPT
0x56C
0x570
0x574
0x578
0x57C
0x700 HDCP_VALIDATE_SRM
0x704 HDCP_VALIDATE_STREAM
0x708 HDCP_TEST_SECURE_STATUS
0x70C HDCP_SET_DCP_KPUB
0x710 HDCP_SET_RX_KPUB
0x714 HDCP_SET_CERT_RX
0x718 HDCP_SET_SCRATCH_BUFFER
0x71C HDCP_SET_SRM
0x720 HDCP_SET_RECEIVER_ID_LIST
0x724 HDCP_SET_SPRIME
0x728 HDCP_SET_ENC_INPUT_BUFFER
0x72C HDCP_SET_ENC_OUTPUT_BUFFER
0x730 HDCP_GET_RTT_CHALLENGE
0x734 HDCP_STREAM_MANAGE
0x738 HDCP_READ_CAPS
0x73C HDCP_ENCRYPT
0x740 [6.0.0+] HDCP_GET_CURRENT_NONCE

Used to encode and send a method's ID over HOST1X to TSEC. This register mirrors the functionality of HOST1X's channel opcode submission.

TSEC_THI_METHOD1

Used to encode and send a method's data over HOST1X to TSEC. This register mirrors the functionality of HOST1X's channel opcode submission.

TSEC_THI_INT_STATUS

Bits Description
0 TSEC_THI_INT_STATUS_FALCON_INT

TSEC_THI_INT_MASK

Bits Description
0 TSEC_THI_INT_MASK_FALCON_INT

FALCON_IRQSSET

Bits Description
0 FALCON_IRQSSET_GPTMR
1 FALCON_IRQSSET_WDTMR
2 FALCON_IRQSSET_MTHD
3 FALCON_IRQSSET_CTXSW
4 FALCON_IRQSSET_HALT
5 FALCON_IRQSSET_EXTERR
6 FALCON_IRQSSET_SWGEN0
7 FALCON_IRQSSET_SWGEN1
8-15 FALCON_IRQSSET_EXT

Used for setting Falcon's IRQs.

FALCON_IRQSCLR

Bits Description
0 FALCON_IRQSCLR_GPTMR
1 FALCON_IRQSCLR_WDTMR
2 FALCON_IRQSCLR_MTHD
3 FALCON_IRQSCLR_CTXSW
4 FALCON_IRQSCLR_HALT
5 FALCON_IRQSCLR_EXTERR
6 FALCON_IRQSCLR_SWGEN0
7 FALCON_IRQSCLR_SWGEN1
8-15 FALCON_IRQSCLR_EXT

Used for clearing Falcon's IRQs.

FALCON_IRQSTAT

Bits Description
0 FALCON_IRQSTAT_GPTMR
1 FALCON_IRQSTAT_WDTMR
2 FALCON_IRQSTAT_MTHD
3 FALCON_IRQSTAT_CTXSW
4 FALCON_IRQSTAT_HALT
5 FALCON_IRQSTAT_EXTERR
6 FALCON_IRQSTAT_SWGEN0
7 FALCON_IRQSTAT_SWGEN1
8-15 FALCON_IRQSTAT_EXT

Used for getting the status of Falcon's IRQs.

FALCON_IRQMODE

Bits Description
0 FALCON_IRQMODE_GPTMR
1 FALCON_IRQMODE_WDTMR
2 FALCON_IRQMODE_MTHD
3 FALCON_IRQMODE_CTXSW
4 FALCON_IRQMODE_HALT
5 FALCON_IRQMODE_EXTERR
6 FALCON_IRQMODE_SWGEN0
7 FALCON_IRQMODE_SWGEN1
8-15 FALCON_IRQMODE_EXT

Used for changing the mode Falcon's IRQs. A value of 1 means level triggered while a value of 0 means edge triggered.

FALCON_IRQMSET

Bits Description
0 FALCON_IRQMSET_GPTMR
1 FALCON_IRQMSET_WDTMR
2 FALCON_IRQMSET_MTHD
3 FALCON_IRQMSET_CTXSW
4 FALCON_IRQMSET_HALT
5 FALCON_IRQMSET_EXTERR
6 FALCON_IRQMSET_SWGEN0
7 FALCON_IRQMSET_SWGEN1
8-15 FALCON_IRQMSET_EXT

Used for setting the mask for Falcon's IRQs.

FALCON_IRQMCLR

Bits Description
0 FALCON_IRQMCLR_GPTMR
1 FALCON_IRQMCLR_WDTMR
2 FALCON_IRQMCLR_MTHD
3 FALCON_IRQMCLR_CTXSW
4 FALCON_IRQMCLR_HALT
5 FALCON_IRQMCLR_EXTERR
6 FALCON_IRQMCLR_SWGEN0
7 FALCON_IRQMCLR_SWGEN1
8-15 FALCON_IRQMCLR_EXT

Used for clearing the mask for Falcon's IRQs.

FALCON_IRQMASK

Bits Description
0 FALCON_IRQMASK_GPTMR
1 FALCON_IRQMASK_WDTMR
2 FALCON_IRQMASK_MTHD
3 FALCON_IRQMASK_CTXSW
4 FALCON_IRQMASK_HALT
5 FALCON_IRQMASK_EXTERR
6 FALCON_IRQMASK_SWGEN0
7 FALCON_IRQMASK_SWGEN1
8-15 FALCON_IRQMASK_EXT

Used for getting the value of the mask for Falcon's IRQs.

FALCON_IRQDEST

Bits Description
0 FALCON_IRQDEST_HOST_GPTMR
1 FALCON_IRQDEST_HOST_WDTMR
2 FALCON_IRQDEST_HOST_MTHD
3 FALCON_IRQDEST_HOST_CTXSW
4 FALCON_IRQDEST_HOST_HALT
5 FALCON_IRQDEST_HOST_EXTERR
6 FALCON_IRQDEST_HOST_SWGEN0
7 FALCON_IRQDEST_HOST_SWGEN1
8-15 FALCON_IRQDEST_HOST_EXT
16 FALCON_IRQDEST_TARGET_GPTMR
17 FALCON_IRQDEST_TARGET_WDTMR
18 FALCON_IRQDEST_TARGET_MTHD
19 FALCON_IRQDEST_TARGET_CTXSW
20 FALCON_IRQDEST_TARGET_HALT
21 FALCON_IRQDEST_TARGET_EXTERR
22 FALCON_IRQDEST_TARGET_SWGEN0
23 FALCON_IRQDEST_TARGET_SWGEN1
24-31 FALCON_IRQDEST_TARGET_EXT

Used for routing Falcon's IRQs.

FALCON_SCRATCH0

Scratch register for reading/writing data to Falcon.

FALCON_SCRATCH1

Scratch register for reading/writing data to Falcon.

FALCON_ITFEN

Bits Description
0 FALCON_ITFEN_CTXEN
1 FALCON_ITFEN_MTHDEN

Used for enabling/disabling Falcon interfaces.

FALCON_IDLESTATE

Bits Description
0 FALCON_IDLESTATE_FALCON_BUSY
1-15 FALCON_IDLESTATE_EXT_BUSY

Used for detecting if Falcon is busy or not.

FALCON_DEBUGINFO

Used for UCODE self revocation. This register takes the base address of the GSC carveout shifted right by 8.

[6.0.0+] nvservices sets this to 0x8005FF00 >> 8 (physical DRAM address inside the GPU UCODE carveout) before starting the nvhost_tsec firmware.

FALCON_EXCI

Contains information about raised exceptions.

FALCON_CPUCTL

Bits Description
0 FALCON_CPUCTL_IINVAL
1 FALCON_CPUCTL_STARTCPU
2 FALCON_CPUCTL_SRESET
3 FALCON_CPUCTL_HRESET
4 FALCON_CPUCTL_HALTED
5 FALCON_CPUCTL_STOPPED
6 FALCON_CPUCTL_SCP_UNK

Used for signaling the Falcon CPU.

FALCON_BOOTVEC

Takes the Falcon's boot vector address.

FALCON_HWCFG

Bits Description
0-8 FALCON_HWCFG_IMEM_SIZE
9-17 FALCON_HWCFG_DMEM_SIZE
18-25 FALCON_HWCFG_MTHD_SIZE
26-31 FALCON_HWCFG_DMATRF_SLOTS

FALCON_DMACTL

Bits Description
0 FALCON_DMACTL_REQUIRE_CTX
1 FALCON_DMACTL_DMEM_SCRUBBING
2 FALCON_DMACTL_IMEM_SCRUBBING
3-6 FALCON_DMACTL_DMAQ_NUM
7 FALCON_DMACTL_SECURE_STAT

Used for configuring the Falcon's DMA engine.

FALCON_DMATRF_EXTBASE

Base of the external memory buffer.

The base of the transfer is calculated by adding #FALCON_DMATRF_POFF to the base.

FALCON_DMATRF_VOFF

For transfers to DMEM: the destination address. For transfers to IMEM: the destination virtual IMEM page.

FALCON_DMATRF_POFF

For transfers to IMEM: the destination physical IMEM page.

FALCON_DMATRFCMD

Bits Description
0 FALCON_DMATRFCMD_FULL
1 FALCON_DMATRFCMD_IDLE
2-3 FALCON_DMATRFCMD_SEC
4 FALCON_DMATRFCMD_IMEM
5 FALCON_DMATRFCMD_WRITE
8-10 FALCON_DMATRFCMD_SIZE
12-14 FALCON_DMATRFCMD_CTXDMA

Used for configuring DMA transfers.

FALCON_DMATRFSTAT

Bits Description
0 FALCON_DMATRFSTAT_PENDING
16-18 FALCON_DMATRFSTAT_NUM_STORES_PENDING
24-26 FALCON_DMATRFSTAT_NUM_LOADS_PENDING

FALCON_CRYPTTRFSTAT

Bits Description
1 FALCON_CRYPTTRFSTAT_PENDING
5 FALCON_CRYPTTRFSTAT_ENABLED
16-18 FALCON_CRYPTTRFSTAT_NUM_STORES_PENDING
24-26 FALCON_CRYPTTRFSTAT_NUM_LOADS_PENDING

FALCON_HWCFG2

Bits Description
0-3 FALCON_HWCFG2_VERSION
4-5 FALCON_HWCFG2_SCP_MODE
6-7 FALCON_HWCFG2_SUBVERSION
8-11 FALCON_HWCFG2_IMEM_PORTS
12-15 FALCON_HWCFG2_DMEM_PORTS
16-19 FALCON_HWCFG2_VM_PAGES_LOG2

FALCON_ICD_CMD

Bits Description
0-3 FALCON_ICD_CMD_OPC
0x0: BREAK
0x1: CONTINUE_FROM_PC
0x2: CONTINUE_FROM_ADDR
0x3: CONTINUE_UNK1_FROM_PC
0x4: CONTINUE_UNK1_FROM_ADDR
0x5: SINGLE_STEP_FROM_PC
0x6: SINGLE_STEP_FROM_ADDR
0x7: SET_BREAK_MASK
0x8: REG_READ
0x9: REG_WRITE
0xA: DATA_READ
0xB: DATA_WRITE
0xC: IO_READ
0xD: IO_WRITE
0xE: STATUS_READ
6-7 FALCON_ICD_CMD_DATA_SIZE
8-12 FALCON_ICD_CMD_IDX
14 FALCON_ICD_CMD_ERROR
15 FALCON_ICD_CMD_DONE
16-31 FALCON_ICD_CMD_BREAK_MASK

FALCON_SCTL

Bits Description
0-1 FALCON_SCTL_SEC_MODE
0: Non-secure
1: Light Secure
2: Heavy Secure

TSEC_SCP_CTL_ACCESS

Bits Description
20 Enable TSEC_SCP_INSN_STAT register

TSEC_SCP_CTL_TRNG

Bits Description
11 Unknown
12 Enable the TRNG

TSEC_SCP_CTL_STAT

Bits Description
20 TSEC_SCP_CTL_STAT_DEBUG_MODE

TSEC_SCP_CTL_MODE

Bits Description
0 Disable reads for the TRNG register block
1 Disable reads for the TFBIF register block
2 Disable reads for the DMA register block
3 Disable reads for the TEGRA register block
4 Disable writes for the TRNG register block
5 Disable writes for the TFBIF register block
6 Disable writes for the DMA register block
7 Disable writes for the TEGRA register block

Controls accesses to the other sub-engines and can only be cleared in Heavy Secure mode.

TSEC_SCP_CTL_PKEY

Bits Description
0 TSEC_SCP_CTL_PKEY_REQUEST_RELOAD
1 TSEC_SCP_CTL_PKEY_LOADED

TSEC_SCP_SEQ0_STAT

Bits Description
8-11 Size of current cs0begin macro

TSEC_SCP_SEQ_STAT

Bits Description
0 Set if crypto sequence recording (cs0begin/cs1begin) is active
4-7 Number of instructions left for the crypto sequence
12-15 Active crypto key register

Contains information on the last crypto sequence (cs0 or cs1) executed.

TSEC_SCP_INSN_STAT

Bits Description
0-7 Crypto fuc5 destination register or immediate value
8-15 Crypto fuc5 source register or immediate value
20-24 Crypto fuc5 operation
0x0:  none (fuc5 opcode 0x00) 
0x1:  cmov (fuc5 opcode 0x84)
0x2:  cxsin (fuc5 opcode 0x88) or xdst (with cxset)
0x3:  cxsout (fuc5 opcode 0x8C) or xdld (with cxset) 
0x4:  crng (fuc5 opcode 0x90)
0x5:  cs0begin (fuc5 opcode 0x94)
0x6:  cs0exec (fuc5 opcode 0x98)
0x7:  cs1begin (fuc5 opcode 0x9C)
0x8:  cs1exec (fuc5 opcode 0xA0)
0x9:  invalid (fuc5 opcode 0xA4)
0xA:  cchmod (fuc5 opcode 0xA8)
0xB:  cxor (fuc5 opcode 0xAC)
0xC:  cadd (fuc5 opcode 0xB0)
0xD:  cand (fuc5 opcode 0xB4)
0xE:  crev (fuc5 opcode 0xB8)
0xF:  cprecmac (fuc5 opcode 0xBC)
0x10: csecret (fuc5 opcode 0xC0)
0x11: ckeyreg (fuc5 opcode 0xC4)
0x12: ckexp (fuc5 opcode 0xC8)
0x13: ckrexp (fuc5 opcode 0xCC)
0x14: cenc (fuc5 opcode 0xD0)
0x15: cdec (fuc5 opcode 0xD4)
0x16: csigauth (fuc5 opcode 0xD8)
0x17: csigenc (fuc5 opcode 0xDC)
0x18: csigclr (fuc5 opcode 0xE0)
31 Set if running in secure mode (cauth)

Contains information on the last crypto instruction executed.

TSEC_SCP_AES_STAT

Bits Description
0-4 First opcode
5-9 Second opcode
15-16 AES operation
0: Encryption
1: Decryption
2: Key expansion
3: Key reverse expansion

Contains information on the last AES sequence executed.

TSEC_SCP_IRQSTAT

Bits Description
1 TSEC_SCP_IRQSTAT_TRNG
8 TSEC_SCP_IRQSTAT_HALT
12 Unknown
16 TSEC_SCP_IRQSTAT_INSN_ERROR
20 TSEC_SCP_IRQSTAT_SINGLE_STEP
24 Unknown
28 Unknown

Used for getting the status of crypto IRQs.

TSEC_SCP_IRQMASK

Bits Description
1 TSEC_SCP_IRQMASK_TRNG
8 TSEC_SCP_IRQMASK_HALT
12 Unknown
16 TSEC_SCP_IRQMASK_INSN_ERROR
20 TSEC_SCP_IRQMASK_SINGLE_STEP
24 Unknown
28 Unknown

Used for getting the value of the mask for crypto IRQs.

TSEC_SCP_ERR

Bits Description
0 Invalid instruction
4 Empty crypto sequence
8 Crypto sequence is too long
12 Crypto sequence was not finished
16 Invalid cauth signature (during csigenc, csigclr or csigunk)
24 Forbidden instruction

Contains information on crypto errors generated by the TSEC_SCP_IRQSTAT_INSN_ERROR IRQ.

TSEC_TFBIF_MCCIF_FIFOCTRL

Bits Description
0 TSEC_TFBIF_MCCIF_FIFOCTRL_RCLK_OVERRIDE
1 TSEC_TFBIF_MCCIF_FIFOCTRL_WCLK_OVERRIDE
2 TSEC_TFBIF_MCCIF_FIFOCTRL_WRCL_MCLE2X
3 TSEC_TFBIF_MCCIF_FIFOCTRL_RDMC_RDFAST
4 TSEC_TFBIF_MCCIF_FIFOCTRL_WRMC_CLLE2X
5 TSEC_TFBIF_MCCIF_FIFOCTRL_RDCL_RDFAST
6 TSEC_TFBIF_MCCIF_FIFOCTRL_CCLK_OVERRIDE
7 TSEC_TFBIF_MCCIF_FIFOCTRL_RCLK_OVR_MODE
8 TSEC_TFBIF_MCCIF_FIFOCTRL_WCLK_OVR_MODE

TSEC_MCCIF_FIFOCTRL1

Bits Description
0-15 TSEC_TFBIF_MCCIF_FIFOCTRL1_SRD2MC_REORDER_DEPTH_LIMIT
16-31 TSEC_TFBIF_MCCIF_FIFOCTRL1_SWR2MC_REORDER_DEPTH_LIMIT

TSEC_TFBIF_UNK5

Used to control accesses to DRAM.

[6.0.0+] The nvhost_tsec firmware sets this register to 0x10 or 0x111110 before reading memory from the GPU UCODE carveout.

TSEC_TFBIF_UNK6

Used to control accesses to DRAM.

[6.0.0+] The nvhost_tsec firmware sets this register to (data_size << 4) before reading memory from the GPU UCODE carveout.

TSEC_DMA_CMD

Bits Description
0 TSEC_DMA_CMD_READ
1 TSEC_DMA_CMD_WRITE
4-7 TSEC_DMA_CMD_UNK
12 TSEC_DMA_CMD_BUSY
13 TSEC_DMA_CMD_ERROR
31 TSEC_DMA_CMD_INIT

A DMA read/write operation requires bits TSEC_DMA_CMD_INIT and TSEC_DMA_CMD_READ/TSEC_DMA_CMD_WRITE to be set in TSEC_DMA_CMD.

During the transfer, the TSEC_DMA_CMD_BUSY bit is set.

Accessing an invalid address causes bit TSEC_DMA_CMD_ERROR to be set.

TSEC_DMA_ADDR

Takes the address for DMA transfers between TSEC and HOST1X (master and clients).

TSEC_DMA_VAL

Takes the value for DMA transfers between TSEC and HOST1X (master and clients).

TSEC_DMA_UNK

Always 0xFFF.

TSEC_TEGRA_CTL

Bits Description
16 TSEC_TEGRA_CTL_TKFI_KFUSE
17 TSEC_TEGRA_CTL_TKFI_RESTART_FSM_KFUSE
24 TSEC_TEGRA_CTL_TMPI_FORCE_IDLE_INPUTS_I2C
25 TSEC_TEGRA_CTL_TMPI_RESTART_FSM_HOST1X
26 TSEC_TEGRA_CTL_TMPI_RESTART_FSM_APB
27 TSEC_TEGRA_CTL_TMPI_DISABLE_OUTPUT_I2C

Authenticated Mode

Entry

From non-secure mode, upon jumping to a page marked as secret, a secret fault occurs. This causes the CPU to verify the region specified in $cauth against the MAC loaded in $c6. If the comparison is successful, the valid bit (bit0) is set on all pages in the $cauth region, and $pc is set to the base of the $cauth region. If the comparsion fails, the CPU is halted.

Exit

The CPU automatically goes back to non-secure mode when returning back into non-secret pages. When this happens, the valid bit (bit0) in the TLB flags is cleared for all secret pages.

Implementation

Under certain circumstances, it is possible to observe csigauth being briefly written to TSEC_SCP_INSN_STAT as "csigauth $c4 $c6" while the opcodes in TSEC_SCP_AES_STAT are set to "cxsin" and "csigauth", respectively.

Via TSEC_SCP_SEQ0_STAT it can be observed that a 3-sized macro sequence is loaded into cs0 during a secure mode transition.

Crypto processing

Part of the information here (which hasn't made it into envytools documentation yet) was shared by mwk from reverse engineering falcon processors over the years.

cauth

$cauth is a special purpose register in the CPU.

Bits Description
0-7 Start of region to authenticate (in 0x100 pages)
8-15 Unused
16 Use secret xfers (?)
17 Region is signed and encrypted and double the size (?)
18
19
20-23 Unused
31-24 Size of region to authenticate (in 0x100 pages)

SCP operations

Opcode Name Operand0 Operand1 Operation Condition
0
1 mov $cX $cY $cX = $cY; ACL(X) = ACL(Y);
2 sin $cX N/A $cX = read_stream(); ACL(X) = ???;
3 sout $cX N/A write_stream($cX);
4 rnd $cX N/A $cX = read_trng(); ACL(X) = ???;
5 s0begin immX N/A record_macro_for_N_instructions(0, immX);
6 s0exec immX N/A execute_macro_N_times(0, immX);
7 s1begin immX N/A record_macro_for_N_instructions(1, immX);
8 s1exec immX N/A execute_macro_N_times(1, immX);
9 ?
0xA chmod $cX immY ACL(X) &= immY;
0xB xor $cX $cY $cX ^= $cY; (ACL(X) & 2) && (ACL(Y) & 2)
0xC add $cX immY $cX += immY; (ACL(X) & 2)
0xD and $cX $cY $cX &= $cY; (ACL(X) & 2) && (ACL(Y) & 2)
0xE rev $cX $cY 1; (ACL(Y) & 2)
0xF gfmul $cX $cY 1; (ACL(Y) & 2)
0x10 secret $cX immY $cX = load_secret(immY); ACL(X) = load_secret_acl(immY);
0x11 keyreg immX active_key_idx = immX;
0x12 kexp $cX $cY $cX = aes_kexp($cY); (ACL(Y) & 2)
0x13 krexp $cX $cY $cX = aes_kexp_reverse($cY); (ACL(Y) & 2)
0x14 enc $cX $cY $cX = aes_enc(active_key_idx, $cY); (ACL(active_key_idx) & 3) && (ACL(Y) & 2)
0x15 dec $cX $cY $cX = aes_dec(active_key_idx, $cY); (ACL(active_key_idx) & 3) && (ACL(Y) & 2)
...

ACL

Bit Meaning
0 Valid key
1 Valid data

Initial values

On SCP boot, the ACL is 0x1F for all $cX.

Loading into $cX using xdst instruction sets ACL($cX) to 0x1F.

Spilling a $cX to DMEM using xdld instruction is allowed if (ACL($cX) & 2).

csigauth

00000000: f5 3c XY d8 csigauth $cY $cX

This instruction takes 2 crypto registers as operands and is automatically executed when jumping to a code region previously uploaded as secret.

csigclr

00000000: f5 3c 00 e0 csigclr

This instruction takes no operands and appears to clear the saved cauth signature used by the csigenc instruction.

cchmod

00000000: f5 3c XY a8 cchmod $cY 0X or 00000000: f5 3c XY a9 cchmod $cY 1X

This instruction takes a crypto register and a 5 bit immediate value. It appears to set the crypto registers' ACL bits as follows:

Bits Description
0 Allow register to be used as key in NS or LS mode
1 Allow register to be used as key in HS mode
2 Set register as readable in NS or LS mode
3 Set register as readable in HS mode
4 Set register as writable in NS or LS mode

crng

00000000: f5 3c 0X 90 crng $cX

This instruction initializes a crypto register with random data.

Executing this instruction only succeeds if the TRNG is enabled for the SCP, which requires taking the following steps:

  • Write 0x7FFF to TSEC_TRNG_CLKDIV.
  • Write 0x3FF0000 to TSEC_TRNG_UNK0.
  • Write 0xFF00 to TSEC_TRNG_UNK7.
  • Write 0x1000 to TSEC_SCP_CTL_TRNG.

Otherwise it hangs forever.

cxset

cxset instruction provides a way to change behavior of a variable amount of successively executed DMA-related instructions.

for example: 000000de: f4 3c 02 cxset 0x2

can be read as: dma_override(type=crypto_reg, count=2)

The argument to cxset specifies the type of behavior change in the top 3 bits, and the number of DMA-related instructions the effect lasts for in the lower 5 bits.

Bits Description
0-4 Number of instructions it is valid for (0x1f is a special value meaning infinitely many instructions -- until overriden by another cxset)
5 Crypto destination/source select (0=crypto register, 1=crypto stream)
6 External memory override (0=Disabled, 1=Enabled)
7 Internal memory select (0=DMEM, 1=IMEM)

DMA-Related Instructions

At least the following instructions may have changed behavior, and count against the cxset "count" argument: xdwait, xdst, xdld.

For example, if override type=0b000, then the "length" argument to xdst is instead treated as the index of the target $cX register.

Secrets

Falcon's Authenticated Mode has access to 64 128-bit keys which are burned at factory. These keys can be loaded by using the $csecret instruction which takes the target crypto register and the key index as arguments.

Index Notes Console-unique
0x00 Used by Keygen, nvhost_tsec, nvhost_nvdec_bl020_prod, nvhost_nvdec020_prod, nvhost_nvdec020_ns and acr_ucode firmwares. No
0x01 Used by nvhost_nvdec_bl020_prod firmware.
0x03 Used by nvhost_tsec, nvhost_nvdec020_prod and nvhost_nvdec020_ns firmwares.
0x04 Used by nvhost_tsec, nvhost_nvdec020_prod and nvhost_nvdec020_ns firmwares.
0x05 Used by nvhost_tsec, nvhost_nvdec_bl020_prod, nvhost_nvdec020_prod, nvhost_nvdec020_ns and acr_ucode firmwares.
0x07 Used by [6.0.0+] nvhost_tsec firmware.
0x09 Used by nvhost_tsec firmware.
0x0B Used by nvhost_tsec, nvhost_nvdec020_prod and nvhost_nvdec020_ns firmwares.
0x0F Used by nvhost_tsec firmware.
0x10 Used by [1.0.0-5.1.0] nvhost_tsec firmware.
0x15 Used by nvhost_nvdec_bl020_prod, [5.0.0+] nvhost_nvdec020_prod, [5.0.0+] nvhost_nvdec020_ns and [6.0.0+] nvhost_tsec firmwares.
0x26 Used by KeygenLdr. No
0x3C Used by nvhost_tsec firmware.
0x3F Used by Keygen, nvhost_tsec, nvhost_nvdec020_prod and nvhost_nvdec020_ns firmwares. Yes