Ernie

Ernie is the codename for the Syscon chip. The Syscon is for exemple responsible for handling button input (including power button), reading/writing to non-volatile storage (NVS) for storing system flags (mostly encrypted and signed). For example IDU flag is stored in NVS. Syscon is also responsible for maintaining the physical address to the resume buffer during Suspend. Communication between Kermit and Syscon is mainly through SPI (see SceSyscon) but there are also some GPIO pins connecting the two. The chip model is NEC/Renesas  and is likely custom designed for Sony.

See also: Ernie Secure

= Boot Process =

The following is logged from boot. The timestamp is in seconds (the starting time is irrelevant). The arrow at the start indicates direction: '>' means Kermit to Syscon (MOSI) and '<' means Syscon to Kermit (MISO). Then there is a 2 byte command id or response code, followed by a flag byte (response only), the payload, a checksum byte, and an (response only) unknown byte. Please note that the packets are listed in transfer order but this may not represent the logical order of the packets. It is currently unknown what the logical order should be, but one can guess that a response is "close to" a request.

First some version information seems to be sent from Syscon to Kermit. This is same for cold boot and resume boot. The last response indicates the type of boot where 0xFF80 is resume and 0xFF14 is regular boot.

< [2.048118000000000] 0x0004, flags=00, payload=[0D 06 00 01 | ....], chk=0xE1, unk=0x00 > [2.048118000000000] 0x0001, payload=[ | ], chk=0xFD < [2.048659583333333] 0x0004, flags=00, payload=[00 60 40 00 | .`@.], chk=0x55, unk=0x00 > [2.048659583333333] 0x0005, payload=[ | ], chk=0xF9 < [2.049330083333333] 0x0004, flags=00, payload=[32 30 31 32 31 31 30 38 31 37 30 34 | 201211081704], chk=0x92, unk=0x00 > [2.049330083333333] 0x0002, payload=[ | ], chk=0xFC < [2.054004333333333] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x30 > [2.054004333333333] 0x0080, payload=[12 00 | ..], chk=0x6A < [2.058172916666666] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x30 > [2.058172916666666] 0x0000, payload=[ | ], chk=0xFE < [2.062716333333333] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x30 > [2.062716333333333] 0x0080, payload=[12 00 | ..], chk=0x6A < [2.111457750000000] 0x0004, flags=00, payload=[14 FF | ..], chk=0xE4, unk=0x32

Next some encrypted session is established. A 8 byte nonce is sent from Syscon (it appears random for each boot, cold or warm). Encrypted data from this point on always differs each boot.

> [2.111457750000000] 0x0010, payload=[ | ], chk=0xEE < [2.133389000000000] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0xFF > [2.133389000000000] 0x00A0, payload=[30 00 00 0B 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | 0.......................................], chk=0xFB < [2.150567250000000] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0xFF > [2.150567250000000] 0x0000, payload=[ | ], chk=0xFE < [2.155149500000000] 0x0024, flags=00, payload=[30 01 00 0B 00 00 00 00 A4 B0 EF 23 D6 9A 3A 06 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | 0..........#..:.........................], chk=0x5F, unk=0x00 > [2.155149500000000] 0x00A0, payload=[30 00 00 0B 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | 0.......................................], chk=0xFB < [2.163572000000000] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x01 > [2.163572000000000] 0x00A0, payload=[30 02 00 0B 01 00 00 00 6C 7F E0 79 AA 03 4B B0 96 B7 42 F0 BC F8 62 7A 35 27 53 68 3D 0D ED A7 13 F2 32 77 46 2D 54 F8 | 0.......l..y..K...B...bz5'Sh=.....2wF-T.], chk=0x9B < [2.189271166666667] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x01 > [2.189271166666667] 0x0000, payload=[ | ], chk=0xFE < [2.193866583333334] 0x0024, flags=00, payload=[30 03 00 0B 00 00 00 00 7A 44 6E C8 F5 FA 35 CB 9B E9 E6 A0 B6 5C 85 1D FB A8 89 5C 9C 04 0B 29 34 59 55 EB 1D 98 AB 83 | 0.......zDn...5......\.....\...)4YU.....], chk=0xC6, unk=0x00 > [2.193866583333334] 0x00A0, payload=[30 02 00 0B 01 00 00 00 6C 7F E0 79 AA 03 4B B0 96 B7 42 F0 BC F8 62 7A 35 27 53 68 3D 0D ED A7 13 F2 32 77 46 2D 54 F8 | 0.......l..y..K...B...bz5'Sh=.....2wF-T.], chk=0x9B

Some more data is exchanged. Up until this point all the plaintext payloads appear to be the same from coldboot and warmboot.

< [2.202246333333334] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x03 > [2.202246333333334] 0x088E, payload=[01 22 | ."], chk=0x43 < [2.206411750000000] 0x0004, flags=00, payload=[ | ], chk=0xF9, unk=0x03 > [2.206411750000000] 0x0000, payload=[ | ], chk=0xFE < [2.217062666666667] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x03 > [2.217062666666667] 0x0000, payload=[ | ], chk=0xFE < [2.221620916666667] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x03 > [2.221620916666667] 0x088E, payload=[01 22 | ."], chk=0x43 < [2.229805500000000] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x03 > [2.229805500000000] 0x1082, payload=[80 04 08 | ...], chk=0xDD < [2.233887583333333] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x03 > [2.233887583333333] 0x0000, payload=[ | ], chk=0xFE < [2.238363416666667] 0x0024, flags=00, payload=[FF FF FF FF 01 FF FF FF | ........], chk=0xD7, unk=0x44 > [2.238363416666667] 0x1082, payload=[80 04 08 | ...], chk=0xDD < [2.246473916666667] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0xFF

Now, there appears to be a branch. The next sequence only shows up for cold boots.

> [2.246473916666667] 0x1082, payload=[A0 04 01 | ...], chk=0xC4 < [2.250555000000000] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0xFF > [2.250555000000000] 0x0000, payload=[ | ], chk=0xFE < [2.255030833333334] 0x0024, flags=00, payload=[FF | .], chk=0xD9, unk=0x00 > [2.255030833333334] 0x1082, payload=[A0 04 01 | ...], chk=0xC4 < [2.259176583333333] 0x0004, flags=00, payload=[01 01 13 00 | ....], chk=0xE0, unk=0xFF > [2.259176583333333] 0x1100, payload=[ | ], chk=0xED < [2.263720583333333] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x01 > [2.263720583333333] 0x00D0, payload=[30 00 00 0F 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | 0.......................................], chk=0xC7 < [2.267827000000000] 0x0004, flags=00, payload=[ | ], chk=0xF9, unk=0x01 > [2.267827000000000] 0x0000, payload=[ | ], chk=0xFE < [2.278339666666667] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x01 > [2.278339666666667] 0x0000, payload=[ | ], chk=0xFE < [2.282830833333333] 0x0024, flags=00, payload=[30 01 00 0F 00 00 00 00 E1 CA 65 96 BB 7E 81 7A 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | 0.........e..~.z........................], chk=0x97, unk=0x00 > [2.282830833333333] 0x00D0, payload=[30 00 00 0F 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | 0.......................................], chk=0xC7 < [2.291023500000000] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x01 > [2.291023500000000] 0x00D0, payload=[30 02 00 0F 01 00 00 00 4E D7 C0 7C D5 E8 BB D7 3E 9E 43 7B B2 E3 4D 81 23 C8 C4 BF B8 4D 9B 25 0A 3D C7 45 E6 0D 23 43 | 0.......N..|....>.C{..M.#....M.%.=.E..#C], chk=0x38 < [2.295129250000000] 0x0004, flags=00, payload=[ | ], chk=0xF9, unk=0x01 > [2.295129250000000] 0x0000, payload=[ | ], chk=0xFE < [2.305641750000000] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x01 > [2.305641750000000] 0x0000, payload=[ | ], chk=0xFE < [2.310132916666667] 0x0024, flags=00, payload=[30 03 00 0F 00 00 00 00 5B 3E 5C 5F 11 F9 E4 6A 85 0D 1E 06 9E F9 33 25 9B 95 55 21 39 48 FC 55 C7 BF A7 E4 32 AD FC 65 | 0.......[>\_...j......3%..U!9H.U....2..e], chk=0x55, unk=0x00 > [2.310132916666667] 0x00D0, payload=[30 02 00 0F 01 00 00 00 4E D7 C0 7C D5 E8 BB D7 3E 9E 43 7B B2 E3 4D 81 23 C8 C4 BF B8 4D 9B 25 0A 3D C7 45 E6 0D 23 43 | 0.......N..|....>.C{..M.#....M.%.=.E..#C], chk=0x38 < [2.318358166666667] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x03 > [2.318358166666667] 0x00D0, payload=[30 04 00 0F 00 00 00 00 52 8D 6D BC 90 C9 00 EE FA CA 47 63 10 D1 4A E5 5A FD BB 91 3A 6C DA EF 64 CA 71 01 4A A9 D5 31 | 0.......R.m.......Gc..J.Z...:l..d.q.J..1], chk=0x4B < [2.322464250000000] 0x0004, flags=00, payload=[ | ], chk=0xF9, unk=0x03 > [2.322464250000000] 0x0000, payload=[ | ], chk=0xFE < [2.332976833333333] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x03 > [2.332976833333333] 0x0000, payload=[ | ], chk=0xFE < [2.337468000000000] 0x0024, flags=00, payload=[30 05 00 0F 00 00 00 00 52 8D 6D BC 90 C9 00 EE FA CA 47 63 10 D1 4A E5 5A FD BB 91 3A 6C DA EF 64 CA 71 01 4A A9 D5 31 | 0.......R.m.......Gc..J.Z...:l..d.q.J..1], chk=0xF5, unk=0x00 > [2.337468000000000] 0x00D0, payload=[30 04 00 0F 00 00 00 00 52 8D 6D BC 90 C9 00 EE FA CA 47 63 10 D1 4A E5 5A FD BB 91 3A 6C DA EF 64 CA 71 01 4A A9 D5 31 | 0.......R.m.......Gc..J.Z...:l..d.q.J..1], chk=0x4B < [2.345696333333333] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x05

Then another set of shared sequence. Some differences in the warmboot responses though. On line 18, FF BF FF 74 becomes FF FF FF 74. On line 12, the 00 00 00 00 becomes the physical address of the resume context buffer. Example: F0 1E 1F 41

> [2.345696333333333] 0x00D2, payload=[20 7A 3E 7B 31 DE FC 3A 11 5F 64 E7 AB A4 EC 17 | .z>{1..:._d.....], chk=0x77 < [2.349790333333333] 0x0004, flags=00, payload=[ | ], chk=0xF9, unk=0x05 > [2.349790333333333] 0x0000, payload=[ | ], chk=0xFE < [2.360448916666666] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x05 > [2.360448916666666] 0x0000, payload=[ | ], chk=0xFE < [2.364930250000000] 0x0024, flags=00, payload=[9D 0B BC 4D BA 66 40 2C 63 BE F3 79 D0 31 26 1E 47 3A 64 DE 68 2F AE E2 8A B6 F0 27 37 46 89 16 0E 71 04 FA BF C9 4A A1 DF 4B EF D3 3D 0D 39 CD | ...M.f@,c..y.1&.G:d.h/.....'7F...q....J..K..=.9.], chk=0x11, unk=0x00 > [2.364930250000000] 0x00D2, payload=[20 7A 3E 7B 31 DE FC 3A 11 5F 64 E7 AB A4 EC 17 | .z>{1..:._d.....], chk=0x77 < [2.373236666666667] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x0B > [2.373236666666667] 0x0090, payload=[0C 00 04 | ...], chk=0x5B < [2.377318583333333] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x0B > [2.377318583333333] 0x0000, payload=[ | ], chk=0xFE < [2.381794416666667] 0x0024, flags=00, payload=[00 00 00 00 | ....], chk=0xD5, unk=0x66 > [2.381794416666667] 0x0090, payload=[0C 00 04 | ...], chk=0x5B < [2.385879750000000] 0x0004, flags=00, payload=[40 00 | @.], chk=0xB7, unk=0x00 > [2.385879750000000] 0x0800, payload=[ | ], chk=0xF6 < [2.386382583333333] 0x0004, flags=00, payload=[FF BF FF 74 | ...t], chk=0xC4, unk=0x66 > [2.386382583333333] 0x0100, payload=[ | ], chk=0xFD < [2.386871833333333] 0x0004, flags=00, payload=[10 00 00 00 | ....], chk=0xE5, unk=0x66 > [2.386871833333333] 0x0003, payload=[ | ], chk=0xFB < [2.387380083333333] 0x0000, flags=3F, payload=[ | ], chk=0xBE, unk=0x00 > [2.387380083333333] 0x0006, payload=[ | ], chk=0xF8 < [2.481997666666667] 0x0000, flags=80, payload=[ | ], chk=0x7D, unk=0x00 > [2.481986333333333] 0x00D2, payload=[30 14 F4 B8 84 89 81 AB 3D 07 66 DE AE B6 D3 24 | 0.......=.f....$], chk=0x10 < [2.514678500000000] 0x0020, flags=00, payload=[ | ], chk=0xDD, unk=0x00 > [2.514678500000000] 0x0000, payload=[ | ], chk=0xFE < [2.519163916666667] 0x0020, flags=00, payload=[1A 1F BC 74 AA 16 59 D6 5C E7 FF 5B E0 85 B2 C8 39 2D D6 95 98 2F B7 4B 71 64 34 D7 8D 2C 94 A1 91 CB 73 D7 8D E1 D0 07 E6 1E 0F DA E7 51 BC 69 | ...t..Y.\..[....9-.../.Kqd4..,....s..........Q.i], chk=0x3C, unk=0x00 > [2.519163916666667] 0x00D2, payload=[30 14 F4 B8 84 89 81 AB 3D 07 66 DE AE B6 D3 24 | 0.......=.f....$], chk=0x10 < [2.527551416666667] 0x0000, flags=80, payload=[ | ], chk=0x7D, unk=0x1F > [2.527540083333333] 0x088E, payload=[02 29 | .)], chk=0x3B < [2.531619416666667] 0x0000, flags=00, payload=[ | ], chk=0xFD, unk=0x1F > [2.531619416666667] 0x0000, payload=[ | ], chk=0xFE < [2.542392416666666] 0x0020, flags=00, payload=[ | ], chk=0xDD, unk=0x1F > [2.542392416666666] 0x0000, payload=[ | ], chk=0xFE < [2.546867583333333] 0x0020, flags=00, payload=[ | ], chk=0xDD, unk=0x1F > [2.546867583333333] 0x088E, payload=[02 29 | .)], chk=0x3B

Then, the two boot paths diverge completely (also note the time jump). It is suspected that at this point the kernel is started up on coldboot, and the kernel resumes for warmboot. For cold boot only, we see the beginning init sequence again, which is likely done in SceSyscon.

< [3.322105750000000] 0x0000, flags=00, payload=[0D 06 00 01 | ....], chk=0xE5, unk=0x16 > [3.322105750000000] 0x0001, payload=[ | ], chk=0xFD < [3.326563916666667] 0x0000, flags=00, payload=[32 30 31 32 31 31 30 38 31 37 30 34 | 201211081704], chk=0x96, unk=0x85 > [3.326552583333333] 0x0002, payload=[ | ], chk=0xFC < [3.331090666666667] 0x0000, flags=80, payload=[ | ], chk=0x7D, unk=0x30 > [3.331079333333333] 0x0080, payload=[12 00 | ..], chk=0x6A < [3.331576333333333] 0x0020, flags=00, payload=[ | ], chk=0xDD, unk=0x30 > [3.331576333333333] 0x0080, payload=[12 00 | ..], chk=0x6A < [3.332068833333333] 0x0000, flags=00, payload=[10 00 00 00 | ....], chk=0xE9, unk=0x31 > [3.332068833333333] 0x0004, payload=[ | ], chk=0xFA < [3.332541666666667] 0x0000, flags=00, payload=[00 FF 04 00 | ....], chk=0xF6, unk=0x31 > [3.332541666666667] 0x0103, payload=[ | ], chk=0xFA < [3.336980333333333] 0x0000, flags=00, payload=[10 00 00 00 | ....], chk=0xE9, unk=0x31 > [3.336980333333333] 0x0003, payload=[ | ], chk=0xFB ...

= Packet checksum = The checksum byte of the packet is calculated as the binary negation of the sum of all the bytes of the packet (including the 2 bytes of the command id and the byte for the length). The checksum calculation can be implemented as follows:

= Commands =

Commands are listed in the order seen in cold boot. The numbers in the captured packets indicate the assumed order with some unused packets filtered out (they appear to be resent). The ordering and grouping are assumed and may contain errors.

CMD 0x0001 - GetBaryonVersion
Gets version of the current installed Ernie firmware. Can also be seen in the packet header in Syscon Update. Also sent at kernel boot.

SEND 1   > [2.881037083333333] 0x0001, payload=[ | ], chk=0xFD RESP 1   < [2.881037083333333] 0x0004, flags=00, payload=[0D 06 00 01 | ....], chk=0xE1, unk=0x71 SEND 23  > [4.167151583333333] 0x0001, payload=[ | ], chk=0xFD RESP 23  < [4.167151583333333] 0x0000, flags=00, payload=[0D 06 00 01 | ....], chk=0xE5, unk=0x32

CMD 0x0005 - GetHardwareInfo
See KBL Param.

SEND 2   > [2.881578833333333] 0x0005, payload=[ | ], chk=0xF9 RESP 2   < [2.881578833333333] 0x0004, flags=00, payload=[00 60 40 00 | .`@.], chk=0x55, unk=0x71

CMD 0x0002 - GetBaryonTimestamp
Gets syscon firmware timestamp. Also sent at kernel boot.

SEND 3   > [2.882249083333333] 0x0002, payload=[ | ], chk=0xFC RESP 3   < [2.882249083333333] 0x0004, flags=00, payload=[32 30 31 32 31 31 30 38 31 37 30 34 | 201211081704], chk=0x92, unk=0x00 SEND 24  > [4.171598000000000] 0x0002, payload=[ | ], chk=0xFC RESP 24  < [4.171598000000000] 0x0000, flags=00, payload=[32 30 31 32 31 31 30 38 31 37 30 34 | 201211081704], chk=0x96, unk=0xF7

CMD 0x0080
Unknown. Sends data 0x0012 on FW 3.60. Does not get return data. Also sent at kernel boot.

SEND 4   > [2.895635416666666] 0x0080, payload=[12 00 | ..], chk=0x6A RESP 4   < [2.886923416666667] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x30 RESP 4   < [2.891092083333333] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x30 RESP 4   < [2.895635416666666] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x30 SEND 25  > [4.176620750000000] 0x0080, payload=[12 00 | ..], chk=0x6A RESP 25  < [4.176123750000000] 0x0000, flags=80, payload=[ | ], chk=0x7D, unk=0x30 RESP 25  < [4.176620750000000] 0x0020, flags=00, payload=[ | ], chk=0xDD, unk=0x30

CMD 0x0010 - GetWakeupFactor
See Wakeup factor.

Boot type indicator. 0xFF14 on cold boot. 0xFF80 on resume boot. SEND 5   > [2.950546416666667] 0x0010, payload=[ | ], chk=0xEE RESP 5   < [2.950546416666667] 0x0004, flags=00, payload=[14 FF | ..], chk=0xE4, unk=0x32

CMD 0x00A0
Runs twice. Appears to contain a 8 byte inner header. First packet sends all zeros and gets back a 8 byte random response. This is likely a nonce or challenge. This likely establishes an encrypted session. Encrypted data differs on each boot. There does not appear to be data transferred using the established session.

SEND 6   > [2.994470666666667] 0x00A0, payload=[30 00 00 0B 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | 0.......................................], chk=0xFB RESP 6   < [2.972471333333333] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0xFF RESP 6   < [2.989889500000000] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0xFF RESP 6   < [2.994470666666667] 0x0024, flags=00, payload=[30 01 00 0B 00 00 00 00 CA 71 11 BA 86 87 EF 0D 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | 0........q..............................], chk=0x66, unk=0x00

SEND 7   > [3.033187750000000] 0x00A0, payload=[30 02 00 0B 01 00 00 00 92 45 B4 A5 49 15 CE F2 39 0E 9E 4C BF FA 19 E6 5D CF BA 5A 6E C3 7C ED 2A 6D 4E 79 84 28 1C 2A | 0........E..I...9..L....]..Zn.|.*mNy.(.*], chk=0x97 RESP 7    < [3.002893083333333] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x01 RESP 7    < [3.028592333333334] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x01 RESP 7    < [3.033187750000000] 0x0024, flags=00, payload=[30 03 00 0B 00 00 00 00 12 77 A5 98 67 F7 38 9B B4 54 48 FE 84 82 CF 84 41 42 87 A2 EA D1 CF 9C 5B D1 2A 3F 1E 50 B9 3D | 0........w..g.8..TH.....AB......[.*?.P.=], chk=0x0A, unk=0x00

CMD 0x088E
Unknown. Sends data 0x2201 on FW 3.60 and does not get any response.

SEND 8   > [3.061354583333333] 0x088E, payload=[01 22 | ."], chk=0x43 RESP 8    < [3.041713500000000] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x03 RESP 8    < [3.046148250000000] 0x0004, flags=00, payload=[ | ], chk=0xF9, unk=0x03 RESP 8    < [3.056796250000000] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x03 RESP 8    < [3.061354583333333] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x03

CMD 0x1082 - NVS Read
Get data from NVS. 2-byte offset followed by 1 byte length. For example used to fetch boot-time flags, like Update Mode.

Get Qaf Token area: SEND 9   > [3.078212500000000] 0x1082, payload=[80 04 08 | ...], chk=0xDD RESP 9   < [3.069790250000000] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x03 RESP 9   < [3.073736583333333] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x03 RESP 9   < [3.078212500000000] 0x0024, flags=00, payload=[FF FF FF FF 01 FF FF FF | ........], chk=0xD7, unk=0x77

Get Update Mode: SEND 10  > [3.094879833333333] 0x1082, payload=[A0 04 01 | ...], chk=0xC4 RESP 10  < [3.086322916666667] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0xFF RESP 10  < [3.090404000000000] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0xFF RESP 10  < [3.094879833333333] 0x0024, flags=00, payload=[FF | .], chk=0xD9, unk=0x00

CMD 0x1100 - GetErnieDLVersion
Gets Ernie DownLoader Version i.e. version of Ernie firmware.

SEND 11  > [3.099025500000000] 0x1100, payload=[ | ], chk=0xED RESP 11  < [3.099025500000000] 0x0004, flags=00, payload=[01 01 13 00 | ....], chk=0xE0, unk=0xFF

CMD 0x00D0
Some encrypted transfer that looks close to Syscon in format. Different on each boot. SEND 12  > [3.122679833333333] 0x00D0, payload=[30 00 00 0F 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | 0.......................................], chk=0xC7 RESP 12  < [3.103569583333333] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x01 RESP 12  < [3.107676166666667] 0x0004, flags=00, payload=[ | ], chk=0xF9, unk=0x01 RESP 12  < [3.118188666666667] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x01 RESP 12  < [3.122679833333333] 0x0024, flags=00, payload=[30 01 00 0F 00 00 00 00 9F CC 4A 69 73 E9 C0 5A 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 | 0.........Jis..Z........................], chk=0xDD, unk=0x00

SEND 13  > [3.150031916666667] 0x00D0, payload=[30 02 00 0F 01 00 00 00 98 6D 3A 1E C5 B1 E9 AF 54 65 55 91 3B DF 2B A8 0F AD B0 73 A0 A2 0F EE 5D 0A AF 41 A5 6D 32 20 | 0........m:.....TeU.;.+....s....]..A.m2.], chk=0xF4 RESP 13  < [3.130872500000000] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x01 RESP 13  < [3.134978166666667] 0x0004, flags=00, payload=[ | ], chk=0xF9, unk=0x01 RESP 13  < [3.145539833333333] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x01 RESP 13  < [3.150031916666667] 0x0024, flags=00, payload=[30 03 00 0F 00 00 00 00 F5 19 C0 67 09 80 C6 DB 58 8D FB E1 86 22 D1 00 DA BB D2 AF AA 51 F9 57 7C 56 92 0A 94 D6 60 4D | 0..........g....X....".......Q.W|V....`M], chk=0xF0, unk=0x00

SEND 14  > [3.177452416666667] 0x00D0, payload=[30 04 00 0F 00 00 00 00 87 4E 59 41 22 98 F8 62 BD B4 C8 4F 4C 0A 81 90 47 1E 1E 70 D6 51 57 42 E5 EC 07 A2 D4 CF E5 02 | 0........NYA"..b...OL...G..p.QWB........], chk=0x9A RESP 14   < [3.158257166666667] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x03 RESP 14   < [3.162363250000000] 0x0004, flags=00, payload=[ | ], chk=0xF9, unk=0x03 RESP 14   < [3.172875666666667] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x03 RESP 14   < [3.177452416666667] 0x0024, flags=00, payload=[30 05 00 0F 00 00 00 00 87 4E 59 41 22 98 F8 62 BD B4 C8 4F 4C 0A 81 90 47 1E 1E 70 D6 51 57 42 E5 EC 07 A2 D4 CF E5 02 | 0........NYA"..b...OL...G..p.QWB........], chk=0x44, unk=0x00

CMD 0x00D2 - SNVS RW
This command is used twice during boot and also quite often after boot. Data is different on each boot. Encrypted session using key from handshake above. Second transaction seems to be the firmware version data written during the update process. Likely firmware version check is done here. SEND 15  > [3.204733083333333] 0x00D2, payload=[32 78 88 CF 3E 63 56 19 75 3A 0A 2D F3 49 63 E2 | 2x..>cV.u:.-.Ic.], chk=0xA4 RESP 15  < [3.185595250000000] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x05 RESP 15  < [3.189740333333333] 0x0004, flags=00, payload=[ | ], chk=0xF9, unk=0x05 RESP 15  < [3.200251666666666] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x05 RESP 15  < [3.204733083333333] 0x0024, flags=00, payload=[D3 57 9B F2 A2 45 E2 7A 2A FC 84 12 97 8E 23 5F C8 AB FB 58 97 EC DE 20 94 0A 78 28 C6 EE C5 45 18 29 00 F4 56 22 53 AF 24 47 8E FF B1 5C DA 2F | .W...E.z*.....#_...X......x(...E.)..V"S.$G...\./], chk=0x4C, unk=0xFF SEND 21   > [3.359112250000000] 0x00D2, payload=[1C 0B 9E FF FB 68 90 4B FD C2 05 CD D8 67 4D D0 | .....h.K.....gM.], chk=0x2D RESP 21   < [3.321934500000000] 0x0000, flags=80, payload=[ | ], chk=0x7D, unk=0x00 RESP 21   < [3.354626666666667] 0x0020, flags=00, payload=[ | ], chk=0xDD, unk=0x00 RESP 21   < [3.359112250000000] 0x0020, flags=00, payload=[6C B4 26 F3 CD 32 D3 3E 6F 80 F2 0F 68 F7 E2 96 58 DB 2F BB AB A6 98 DD 26 14 DD 61 12 E4 55 BA BB 32 1D 1F 75 D5 D1 4C 7E 4A 19 42 E5 B0 C6 AB | l.&..2.>o...h...X./.....&..a..U..2..u..L~J.B....], chk=0x84, unk=0xFF

CMD 0x0090 - Scratch Pad Read
This command reads data from Ernie Scratch Pad. This is the inverse of command 0x91.

This is used for example to fetch the saved resume context buffer physical address. Kernel sets this before suspending and this value is passed to the resume function. See Suspend. The format is 2 byte offset and 1 byte length.

SEND 16  > [3.221743166666667] 0x0090, payload=[0C 00 04 | ...], chk=0x5B RESP 16  < [3.213273166666667] 0x0004, flags=80, payload=[ | ], chk=0x79, unk=0x57 RESP 16  < [3.217267333333333] 0x0024, flags=00, payload=[ | ], chk=0xD9, unk=0x57 RESP 16  < [3.221743166666667] 0x0024, flags=00, payload=[F0 0E 1F 41 | ...A], chk=0x77, unk=0x45

CMD 0x0091 - Scratch Pad Write
This command writes data to Ernie Scratch Pad. This is the inverse of command 0x90.

CMD 0x0800 - Get USB Info
See KBL Param.

SEND 17  > [3.225828583333334] 0x0800, payload=[ | ], chk=0xF6 RESP 17  < [3.225828583333334] 0x0004, flags=00, payload=[40 00 | @.], chk=0xB7, unk=0x41

CMD 0x0100 - GetControlsInfo
See Boot Controls Info.

SEND 18  > [3.226331500000000] 0x0100, payload=[ | ], chk=0xFD RESP 18  < [3.226331500000000] 0x0004, flags=00, payload=[FF BF FF 74 | ...t], chk=0xC4, unk=0x45

CMD 0x0003 - GetSleepFactor
See Sleep Factor.

SEND 19  > [3.226820750000000] 0x0003, payload=[ | ], chk=0xFB RESP 19  < [3.226820750000000] 0x0004, flags=00, payload=[10 00 00 00 | ....], chk=0xE5, unk=0x45

CMD 0x0006 - Get Hardware flags
See Hardware flags.

SEND 20  > [3.227328833333333] 0x0006, payload=[ | ], chk=0xF8 RESP 20  < [3.227328833333333] 0x0000, flags=3F, payload=[ | ], chk=0xBE, unk=0x00

CMD 0x088E
Unknown. Appears to be the last command sent before a time-jump (likely indicating completion of early-boot). Might be some status indicator to tell Syscon that we're done. SEND 22  > [3.386554833333333] 0x088E, payload=[02 29 | .)], chk=0x3B RESP 22   < [3.367488416666667] 0x0000, flags=80, payload=[ | ], chk=0x7D, unk=0xB4 RESP 22   < [3.371567833333333] 0x0000, flags=00, payload=[ | ], chk=0xFD, unk=0xB4 RESP 22   < [3.382079833333334] 0x0020, flags=00, payload=[ | ], chk=0xDD, unk=0xB4 RESP 22   < [3.386554833333333] 0x0020, flags=00, payload=[ | ], chk=0xDD, unk=0xB4

CMD 0x0004
Unknown. Likely happens after initial boot. SEND 26  > [4.177113250000000] 0x0004, payload=[ | ], chk=0xFA RESP 26  < [4.177113250000000] 0x0000, flags=00, payload=[10 00 00 00 | ....], chk=0xE9, unk=0x31

CMD 0x0103 - Get Multi Connector Info
Likely happens after initial boot.

SEND 27  > [4.177586083333333] 0x0103, payload=[ | ], chk=0xFA RESP 27  < [4.177586083333333] 0x0000, flags=00, payload=[00 FF 04 00 | ....], chk=0xF6, unk=0x31

= Syscon Scratch Pad =

Types
= NVS =

Ernie Non-volatile storage (NVS) is a persistent storage allocated on Ernie Data Flash that is used by PS Vita OS for data required at boot time. Indeed, reading NVS requires no driver except the driver to communicate with Syscon, whilst reading PS Vita eMMC requires its AES-XTS decryption.

Not every NVS sector is directly readable from Kermit: some sectors are part of SNVS (Secure NVS) which means that they are XTS encrypted and must be accessed through a Secure handshake.

On FW 3.60, NVS size is 0xB60 bytes:
 * Area from 0 to 0x3FF cannot be read using SceSblSsMgr nor written using SceSblSsMgr. This area is handled by Secure Modules. See Ernie Secure.
 * Area from 0x400 to 0x75F is handled by NS Kernel SceSblSsMgr.
 * Area from 0x760 to 0xB5F are reserved for Test and Tool consoles. However this area seems unused.

Types
= Config Storage =

Config Storage is a similar storage than NVS but is accessed in a different manner. Whilst NVS is read and written by 32-byte sectors and is physically stored with a sort of history, Config Storage is written by sending scripts from Kermit to Syscon, and is not really readable but instead affects KBL Param.

Sample scripts
Below are sample configstorage scripts hardcoded in SceSyscon:

The only actual differences between those scripts are:
 * the ascii string: we do not know how it is generated and what it means
 * the mode value:
 * A8 01 00 00 00 00 = mode clear
 * A8 01 01 00 0D 00 = idu mode set
 * A8 01 03 00 10 00 = show mode set

Types
Config storage scripts have in theory a variable size. It is the concatenation of some blocks where the first byte is the length of the body, followed by the body of variable size. Body structure is always the same: 1 byte representing the flag, followed by data of variable size.

Usage
Theory by CelesteBlue (untested):
 * 0) Begin Transaction


 * 1) Load Script (part 1)
 * A) configstorage data is read from SceSyscon memory
 * B) configstorage data is sent by SceSyscon to Ernie
 * C) Ernie FW checks hash of data and returns xx on success

if success:
 * 2) Load Script (part 2)
 * A) configstorage data is read from SceSyscon memory
 * B) configstorage data is sent by SceSyscon to Ernie using Load
 * C) Ernie FW loads data to memory and executes it


 * 6) Commit Transaction
 * 7) End Transaction

= Pinout =



A candidate package for this chip is Renesas' P121F1-50-BAL-1. It has the same size and number of pins.

SPI
Main communication with Kermit.

Other
= Versions =

Hardware Versions
There are three hardware versions of Ernie:
 * NEC 78K0R/Kx3-L: present on early PS Vita prototypes (never seen)
 * NEC 78K0R/Kx3: present on Fat PS Vita and PS TV models, including some prototypes such as DEM-3000L
 * Renesas RL78/G13: present on Slim PS Vita models

NEC 78K0R/Kx3-L
Never seen yet but exists according to Ernie update packages.

NEC 78K0R/Kx3
NEC D79F0109 (78K0R/KH3, 121 pin)

Device Name : D79F0109

Other Device Name : SK0RT02N200GV120 (on DEM-3000L and PCH-1000)

Label: Model <- always D79F0109 Revision <- on DEM-3000H: ES1.0, blank on others Build <- XXYYZZWWW <- XX: year, YY: week, ZZ: 2 letters (unknown usage), WWW: serial number Manufacturing country <- always "MALAYSIA"

Renesas RL78/G13
Renesas R5F1ZCRK (RL78/G13, 121 pin)

R5F1ZCRKABG#U0 R5   Renesas MCU F     Flash 1     RL78 Z     Customer specific C     Product group R     121-pin K     384KB A     Consumer grade BG   VFBGA 0.4mm
 * 1) U0 Tray*2

Device Name : R5F1ZCRK Device Code : 10 00 06 Firmware Version : V3.03 Code Flash 1 (Address : 0x00000000, Size : 384 K,  Erase Size : 1 K) Data Flash 1 (Address : 0x000F1000,  Size : 8 K,  Erase Size : 1 K)

Label: (C) XXXX <- Year Revision <- A0xxx SCEI Build <- XXYYZZWWW <- XX: year, YY: week, ZZ: 2 letters (unknown usage), WWW: serial number Unknown data

Block sizes
Ernie flash memory is erasable in blocks. Size of one block in bytes depends on the hardware version:
 * NEC 78K0R/Kx3-L: 0x800
 * NEC 78K0R/Kx3: 0x400
 * Renesas RL78/G13: 0x400

See also.

Software Versions
See also.

Ernie firmware can be partly updated and downgraded with software updates embedded in PUP.

Ernie firmware is dependant of the hardware version and detects it based on Hardware Info.

Examples
With DevKit connected,  queries return the following results:

DEM-3000H running FW 0.990: -> converted to hexadecimal: 0x00090501 -> 0.9.5.1

PDEL-1001 running FW 1.692:

PDEL-1001 running FW 3.600-3.680:

Downgrade
Syscon is downgradable on DEM/PDEL/PTEL/QAF units. It might also be downgraded on retail when using a downgrade enabler like modoru.

= Firmware =

See Ernie Firmware