Iplloader

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The PRE-IPL, called "Lib-PSP iplloader" internally by sony, is the first code to run in PSP MIPS32 main CPU. Its role is to load the Initial Program Loader. PRE-IPL is where the routines to boot into service mode are and loads & decrypts the encrypted IPL from the nand/MS).

Location

On retail PSP units PRE-IPL is read from the Tachyon (Allegrex MIPS R4000 based SOC) boot rom. On DTP-T1000 it is loaded externally.

The PSP main CPU is a custom-made Sony CPU with a MIPS32 core and has an embedded mask rom device (like most embedded systems do) which is exactly 4KB in size. This device holds the PRE-IPL. This PRE-IPL mask rom device is mapped to physical address 0x1FC00000 (this is the address of reset exception vector on MIPS CPUs), and this is where the CPU starts executing from coldboot.

Structure

The PRE-IPL is made up of 2 parts, the "loader", and the "payload".

TODO

PRE-IPL Versions

A few example of PRE-IPL payload sizes and hashes are:

SDK Version Date (DD-MM-YYYY) Payload Size Hash
Tachyon 0x00140000-0x00300000 20-04-2004 (build date in ROM) 0xAF8 SHA-256: 48F4F11C383621C8569EC07273AE0AF6AD79681CF5B77263A69CF908EEFE4A53 (ROM)
0.4.0 23-07-2004 (or older/last modified date for kbooti.bin) n/a SHA-256: 18B5BF7AEFE956D99B397AAAAC94DC965ADFDBC2BE0532096BBC1F8F8C5B7C34 (Full Binary)
0.6.0 08-09-2004 (or older/last modified date for kbooti.bin) n/a SHA-256: 5CDEDDEBE11807DDAEB17BAC03945A0B828E8057C9587652CA207E3BB959AC96 (Full Binary)
0.7.0 18-09-2004 (build date in the payload) 0x894 SHA-256: 351ECD64C945489999D477ECAFBFBB8FE769C2484636D2F7323557F7EEFD54A2 (payload only)
SHA-256: 388FA1DB87973A2A37D576AAAB785D840CA4D883AB5111781DA2D0AF59CFE667 (Full decrypted binary)
0.9.0 15-10-2004 (build date in the payload) 0x894 SHA-256: 4F794E4FF32D5267AEAEDBA362D005EF0B7E93E29CF7C8209E0D9DBB0144F4DB (payload only)
SHA-256: E415198C16E29D96C9232FF78272EE639D0630A56E370ED18A33D358FEF7CA95 (Full decrypted binary)
Tachyon 0x00400000-0x00500000 04-01-2005 (build date in ROM) 0xB30 SHA-256: 41B2578F84BDE33E09356F0170FF99E2417EA7B1D02BD9163A41AE61FE74C3A5 (ROM)
2.6.0 22-10-2005 (build date in the payload) 0xBF4 SHA-256: 8821D96F5FB35C55DF649A97F5703F8A705362C2F54665B5EE4221E686B5578A (payload only)
SHA-256: 0A83CB36F1FE7C2A9A53BD46E6FFD915D4D1BB97EED3D1EF336960DB752C3446 (Full decrypted binary)
2.7.1 14-02-2006 (build date in the payload) 0xBF4 SHA-256: F9160C03EC6174F54F1C1EB645CFBBDB65B3DA47DA1A5478BE30E5EB2B0852B4 (payload only)
SHA-256: 7DDFF7093906C10BA11D7402E9939763173F1ADEA59A38B4006484FD18EA21EA (Full decrypted binary)
3.5.0 12-02-2007 (build date in the payload) 0xC74 SHA-256: AAF6F3CF0D7E028F43BE6FB788018F7A6F49B140A2591937B5C3A8373D2186A5 (payload including xor key)
SHA-256: 5066E257EC43DA37788535C331E5A01955F5F498B103C340903409649BCB5046 (full binary)
0.931-0.995 (inside PSVita Compatibility Secure Module) 11-17-2010 (last modified date for 0.940I compat_sm.self) 0x2C0 SHA-256: 6D75EC720739C53228B1CA1AFF6CE073AE542BBB38FCC9B8710EC5EB3889B942 (Full Binary)
0.996.070-0.996.090 (inside PSVita Compatibility Secure Module) 07-22-2011 (last modified date for compat_sm.self) 0xD34 SHA-256: E09B36DE655A441D2C94D39EF7BBC505EAB1722E9380EBE73E9E6A7DC88D9731 (Full Binary)
1.000.041-1.06 (inside PSVita Compatibility Secure Module) 08-30-2011 (last modified date for compat_sm.self) 0xDB4 SHA-256: C2AE6939BC4B06CB4A81415E27EB1E7129C561B9C16C3AAFF6FDEBBAB48EBD09 (Full Binary)
1.50-1.81 (inside PSVita Compatibility Secure Module) 12-14-2011 (last modified date for compat_sm.self) 0xE34 SHA-256: 522851781DD82F89D69EBFE0F25C3E7CFE5899A53E850F2F979AD1B0E53376F9 (Full Binary)
2.00-2.05 (inside PSVita Compatibility Secure Module) 11-16-2012 (last modified date for compat_sm.self) 0xE34 SHA-256: A9A097ED8925B83A210202AA4C943011C05FE48028BA6E05E85E1494143B0100 (Full Binary)
2.06-2.12 (inside PSVita Compatibility Secure Module) 02-22-2013 (last modified date for compat_sm.self) 0xE34 SHA-256: 25E22C1D988609AA948F103E1312297F9533CA689B3C1BDC2CECBBC43997D566 (Full Binary)
2.50-3.01 (inside PSVita Compatibility Secure Module) 06-27-2013 (last modified date for compat_sm.self) 0xE34 SHA-256: 187DD28ADAD4167F3849392D570CA5A56DEEC608156D0EC6F2453958B1DB9672 (Full Binary)
3.10-3.20 (inside PSVita Compatibility Secure Module) 12-05-2013 (last modified date for compat_sm.self) 0xE34 SHA-256: EF7D498295E416CCBD79FED78656E683DA1DCBC7B88C521DF0A1E00F5EC450FE (Full Binary)
3.30-3.35 (inside PSVita Compatibility Secure Module) 09-25-2014 (last modified date for compat_sm.self) 0xE34 SHA-256: 7DF591C05BF66292B6868CE4331A1DC11B7A0E421D082971E9CA65C7236B6843 (Full Binary)
3.36-3.50 (inside PSVita Compatibility Secure Module) 01-09-2015 (last modified date for compat_sm.self) 0xE34 SHA-256: 7E66976C311F5D3797A30B09DC608A0FA2E67EAA060097423CFD2E5FC89A57D9 (Full Binary)
3.51-3.55 (inside PSVita Compatibility Secure Module) 05-12-2015 (last modified date for compat_sm.self) 0xE34 SHA-256: 6E869E08CCE41E0AA0D386DE8936F81F66CABB20B964C3EF2159548852F39F30 (Full Binary)
3.57-3.63 (inside PSVita Compatibility Secure Module) 11-25-2015 (last modified date for compat_sm.self) 0xE34 SHA-256: 047366634210449C62FD813B3BFDA6267A1FA8683BA17901A214FC32E473A35F (Full Binary)
3.65-3.70 ?3.73? (inside PSVita Compatibility Secure Module) 03-17-2017 (last modified date for compat_sm.self) 0xE34 SHA-256: B5EF4FB2C84D629B2BDC9A70A4B8E5A7EC31CD9EA330E309361C80A9A96B65C5 (Full Binary)

Behaviour

PRE-IPL Boot Sequence

Part1 PRE-IPL (the loader)

Because the PRE-IPL is stored in non-volatile read-only memory it cannot use variables, so the Part1 PRE-IPL code (the loader) copies the Part2 PRE-IPL (the payload) to the CPU's scratchpad RAM (the only RAM available at this time, along with another 4KB block of RAM and the 2MB EDRAM - normal DDR SDRAM hasnt been initialised yet). The scratchpad RAM is mapped to physical address 0x00010000, and after Part1 has finished copying Part2 to it, it jumps to this new address.

Part2 PRE-IPL (the payload)

Now the CPU is executing from the scratchpad RAM (the PRE-IPL payload). The PRE-IPL payload inits the nand hardware and reads the IPL nand-block-table (a table with the physical block numbers of the encrypted IPL's location on the nand). The table is located at the 4th physical block of the nand (offset 0x10000), and is repeated for the next 7 blocks. This is so that if a bad block occurs in any of these blocks, the table can still be read. Though if all 8 blocks become bad blocks, its a non-recoverable brick as the PRE-IPL can no longer locate the IPL's location (the only solution to this problem is to either boot from MS instead, or use a custom IPL to patch the PRE-IPL to remap the table - both of which would still require Pandora).

The entire raw IPL is stored on the nand encrypted. The PRE-IPL payload uses a 4KB RAM (this RAM is mapped to physical address 0x1FD00000, but will later be remapped to 0x1FC00000 to be used for the ME CPU reset exception vector) as a temporary location to load & decrypt each encrypted IPL block. Because this RAM is only 4KB in size, the encrypted IPL is organised as 4KB blocks on the nand. As the PRE-IPL decrypts each of the 4KB IPL blocks, it loads the decrypted blocks to the IPL entry address 0x040F0000 (this address is located in the 2MB EDRAM which is normally used as VRAM, normal DDR RAM still has not been initialised yet). When the PRE-IPL has finished decrypting and loading all the encrypted IPL blocks, it jumps to the IPL entry address.

Memory mapping

The PRE-IPL is mapped to 0xBFC00000 which is the reset vector of PSP's MIPS R4000 CPU.

0.7.0 PRE-IPL and onward are composed of two parts: a loader from 0xBFC00000 to 0xBFC0027F and a payload from 0xBFC00280 and ending at the size specified at 0xBFC000034 (little endian 0x2 bytes).

PSVita's PRE-IPL from version 0.996 and onward's payload starts at 0xbfc00180, rather than 0xbfc00280 on previous and PSP hardware versions.

Devkit behaviour

bloadp

bloadp is used to send kbooti binaries (encrypted PRE-IPL data from 0x0 to 0x1000 and IPL blocks at 0x1000) to the DTP-T1000.

bloadp will (through tachsm) initialize the 0x1D600000 memory (from /dev/mem or 0x00000000 from /dev/tachsm0 ; /dev/tachsm1 is mapped from 0x1D400000 to 0x1D5FFFFF) on the Communication Processor side (0x200000 in size, 0x100000 on the tachsm0 device) which is the DTP-T1000 PSP Shared memory, on the psp/tachyon side it is mapped to 0xBFE00000, it will then write the kbooti binary at 0x1D600000, however on SDK 0.5.0 and below dstdb (which bloadp was originally a part of), it was possible to specify the address to which kbooti would be loaded (default address to be specified was 0xbfc00000, the allowed range was 0xbfc00000-0xbfc10000), this in effect would write kbooti to 0x1D600000/0xBFE00000 + the address specific in the range -0xbfc00000, so for instance if 0xbfc02000 was specified, this would write kbooti to 0xBFE02000, keep in mind that the actual 0xBFC00000 memory mirrors itself every 0x1000 segments.

If bloadp is never invoked, 0x1D700000 to 0x1D7FFFFF is uninitialized memory. It is cleared out as soon as bloadp is invoked.

Prototype 0.4.0-0.6.0 (23-07-2004 or older)

Prototype PRE-IPL will read the IPL blocks in place from 0xBFE01000 and decrypts them to 0x88400000 before jumping there. IPL blocks have no metadata in prototype IPLs. Instead PRE-IPL uses 0x88400000 as a hardcoded entry point (see code samples below). In fact the IPL payload/part3, nested inside current IPL revisions and loaded by main.bin are using the prototype format, so the prototype PRE-IPL loads the IPL part 3/payload directly.

It is also worthy of note that prototype PRE-IPL for DEM-1000 (for 0.4.0 and 0.6.0 firmwares) does not make use of paddr 0xa0010000 as their payload location. The PRE-IPL payload is instead executed in place at 0xBFC00000. As such the PRE-IPL data is not wiped and can be dumped in its entirety using a custom IPL (please note that the IPL format is different than later revision IPLs: prototype IPLs are loaded in a single raw KIRK commmand 1 block).

// 0.4 PRE-IPL
    }
    // 0xbfc00138
    function_bfc00178(100);
    uint32_t v9 = function_bfc00550(0x8400000, 0x1fe01000); // 0xbfc0014c
    // branch -> 0xbfc00154
    while (v9 < 0) {
        // 0xbfc00154
        // continue -> 0xbfc00154
    }
    // 0xbfc00158
    return unknown_88400000(-0x78000000, v8);
}
// 0.6 PRE-IPL
    // 0xbfc00168
    function_bfc001b0(100);
    uint32_t v13 = function_bfc006b0(0x8400000, 0x1fe01000); // 0xbfc0017c
    // branch -> 0xbfc00184
    while (v13 < 0) {
        // 0xbfc00184
        // continue -> 0xbfc00184
    }
    // 0xbfc00188
    return unknown_88400000(-0x78000000, v9, v10, v1);
}

0.7.0-2.50 (18-09-2004)

The 0.7.0+ PRE-IPL will copy its PRE-IPL payload (stored at 0xBFC000280) to 0x80010000 (physical address 0xa0010000) and jump there. Because on DTP-T1000 0xBFC00000 is writable during PRE-IPL execution and because 0xBFD00000 is an invalid range on DTP-T1000, the payload will use the 0xBFC00000 memory (which originally contains the whole PRE-IPL loader+payload) as work ram. It will however not wipe itself so you can dump the important part (the payload) from 0xa0010000 (assuming you gain execution at IPL time).

IPL blocks are then loaded from 0xBFE01000 by PRE-IPL and copied to 0xBFC00000 where they are decrypted in place and copied to the location of load address specified in the metadata.

2.60+ (22-10-2005)

Because a hash of the data stored between 0xbfc00040 and 0xbfc002c0 is used in an additional step by 2.60+ IPLs to decrypt main.bin, from 2.60 and onward the payload will overwrite 0xbfc00000 with an identical copy of first 0x2C0 bytes of the original psp-1000(01g) PRE-IPL rom data (stored at 0xBFC00BB0 in the 2.60 and 2.71 kbooti, 0x80010930 in the payload) and wipe everything after 0xbfc002C0 with 00 before jumping to the IPL entrypoint, if bootstrapping the 1.50 firmware using the 2.60/2.71 PRE-IPL part, data from the retail rom addresses 0xBFC00200 to 0xBFC002C0 is retrievable, please note that this would not have been enough to generate the hash required to decrypt 2.60+ main.bin in any case and dumping using a custom IPL would be required to retrieve enough of the data even on a DTP-T1000.

2.6.0 kbooti also appears to fix one of the PRE-IPL flaws that allowed to load the Pandora time attacked block. It likely either checks for the entrypoint not to be in the 0xb* range or prevents the use of IPL blocks with 0x0 set as a load address (or both), it does not however check for the data size of the block.

The code that copies 0x2C0 bytes from 0x80010930 to 0xbfc0 verbatim from the 2.6.0 PRE-IPL payload.

0x800100c4:   19 00 20 13   	beq 0x8001012c <entry_point+0x12c>, $zero, 0x8001012c <entry_point+0x12c>
0x800100c8:   00 00 00 00   	sll $zero, $zero, 0x0
0x800100cc:   8f 40 00 0c   	jal 0x8001023c <function_8001023c>
0x800100d0:   00 00 00 00   	sll $zero, $zero, 0x0
0x800100d4:   81 40 00 0c   	jal 0x80010204 <function_80010204>
0x800100d8:   00 00 00 00   	sll $zero, $zero, 0x0
0x800100dc:   c0 bf 04 3c   	lui $a0, 0xbfc0
0x800100e0:   21 28 00 00   	addu $a1, $zero, $zero
0x800100e4:   00 10 06 24   	addiu $a2, $zero, 0x1000
0x800100e8:   5a 41 00 0c   	jal 0x80010568 <function_80010568>
0x800100ec:   00 00 00 00   	sll $zero, $zero, 0x0
0x800100f0:   c0 bf 04 3c   	lui $a0, 0xbfc0 #0xbfc000000
0x800100f4:   01 80 05 3c   	lui $a1, 0x8001
0x800100f8:   30 09 a5 24   	addiu $a1, $a1, 0x930 #0x80010930
0x800100fc:   00 00 06 3c   	lui $a2, 0x0
0x80010100:   c0 02 c6 24   	addiu $a2, $a2, 0x2c0 #size of the data (0x2C0)
0x80010104:   50 41 00 0c   	jal 0x80010540 <function_80010540>

Please note that neither the 0xbfc00000 (on DTP-T1000) nor 0xa0010000 memory locations survive reboots.

3.50 (12-02-2007)

PRE-IPL adds a step using a 0x40 bytes xor key to decrypt the CMAC hash and data keys from the IPL block headers. As a result you cannot decrypt using KIRK command 1 the IPL blocks meant for the new PRE-IPL.

The xor key is overwritten early using a memset to 0 whenever the special JIG emulation mode is used (so the IPL block is xored by 0), this makes it impossible to obtain without glitching, knowing the kbooti CBC encryption key, knowing the xor key beforehand or using an IPL Loader exploit.

   if ( MEMORY[0xBFEFFFFC] < 0 )
   sub_800105F0(&unk_8001088C, 0, 64);

The seed for the IPL decryption (as it is used since 2.6.0) has changed to become a pseudo random 0x2C0 sized blob that is copied back from 0x800109B0 to 0xBFC00000 before jumping to the IPL entry point. SHA-256: 1E6FC02124901F6F5A3F1BB02F065064C63E423D759A131BA1086EA8FC2D90AA

JIG Memory Stick Test Mode

Starting from kbooti 0.7.0, a special JIG test mode exists, it will read an IPL block at 0x2000 on the Memory Stick instead of address 0xBFE01000 if the specific condition is met:

   if ( MEMORY[0xBFEFFFFC] < 0 ) use MS

Writing 0xFFFFFFFF at 0xBFEFFFFC does indeed enable the pseudo service mode and reads the block from the Memory stick, this mode is used by Sony Engineers to debug JIG Memory sticks by writing a kbooti using bloadp and then using reset parameters to set the flag at0xBFEFFFFC using the sbootp param/arg from the reset command of either dstdb or bsreset (dspreset) such as follows: /usr/local/sony/bin/bootdispi/dspreset 80000000 (FFFEFFFF for example sets all boot flags to 0xFF), to set the DTP-T1000 into JIG emulation mode.

Because flags are incremental only the only way to clear the JIG flag using official SDK tools is to run the bloadp command again as this clears the whole tachsm0 memory including the flags.

Kbooti remains loaded in memory until the main unit is turned off or bloadp has ran again, allowing then to power cycle through different memory stick.

In kbooti revision 3.5.0 this mode skips the XOR step (overwrites the xor key with 00s in the scratchpad) on the kirk header, allowing to use a regular IPL block to achieve code execution and dump the payload (without the xor key).

Retail behaviour

pseucode from Tachyon 0x00140000-0x00300000 PRE-IPL payload:

int iplBlockNumber = 0;
u32 checksum = 0;

// load/decrypt all encrypted ipl blocks
while(1)
{
// copy an encrypted ipl block to 0xBFD00000-0xBFD01000 (4KB embedded cpu ram)
if (LoadIplBlock(iplBlockNum ber, block) < 0)
while(1);

// decrypt the ipl block in place (uh oh...)
if (DecryptIplBlock(block, block))
while(1);

// first block will have zero as its checksum since there is no previous block (another uh oh...)
if (block->checksum != checksum)
while(1);

// load the 'data' section of the ipl block to the specified address (0x040Fxxxx range)
if (block->loadaddr)
checksum = memcpy(block->loadaddr, block->data, block->blocksize);

// reached the end of the ipl, jump to the entry address (0x040F0000)
if (block->entry)
{
// clear caches
Dcache();
Icache();

// jump to ipl - do not return
block->entry();
}

iplBlockNumber++;
}

Tachyon revisions 0x00140000 to 0x00300000 PRE-IPL pseudo code:

PSP Disassembler Ver.0.20 Copyright(c)2005,2006 BOOSTER
incl. elf-lib 0.1r2 copyright (c) 2005 djhuevo

:file name '0x80010000.bin',size = 4096
Load 3684 NID's name

:Disasm

;copied by pre-ipl bootcode, from 0xbfc00280-0xbfc00d78
;here code is 0x80010000 to 0x80010af8

;
;$bfd00000-$bfd00fff : sector read buffer
;

;-------------------------------------------------------
;recovery mode selector

;be240004 GPIO READ REG.
;		bit4 : device select ,0=NAND Flash,  1= rec-dev
;
;-------------------------------------------------------

;-------------------------------------------------------
;recovery boot device (rec-dev) HW assign
;
;bd200030	command register
				00009007 : read request (write size = 8)
				00002200 : read sector buffer (read size=200)
				00008004 : ? status (write size = 8 , read size=8)
				00004000 : ? status (read size=8)
				00007001 : ? (data size=8?)

;bd200034	data register (read / write)
;bd200038	status register
;			bit14:read data ready
;			bit13:parameter wirte ready
;			bit12:transmit finish ?
;			bit 9:???? error
;			bit 8:read data error
;
;bd20003c	???
			bit15:reset device ?
;
;-------------------------------------------------------


;---------------------------------------------------------------------------
;entry
;---------------------------------------------------------------------------
L80010000:
;
;reset I/O
	$800106B0(L80010a80)
;
  lui    r8,$bc10                           ;80010010[3C08BC10,'...<']
;
	if(r8[$68]>>16 == 0) $80010034
;
	r9 = r8[$78]
  ori    r9,r9,$0800                        ;80010028[35290800,'..)5']
  b      $80010040                          ;8001002C[10000004,'....']
  sw     r9,$78(r8)                         ;80010030[AD090078,'x...']
;
;80010034
  lw     r9,$7c(r8)                         ;80010034[8D09007C,'|...']
  ori    r9,r9,$0010                        ;80010038[35290010,'..)5']
  sw     r9,$7c(r8)                         ;8001003C[AD09007C,'|...']
  addiu  r4,0,$a                            ;80010040[2404000A,'...$']
  jal    $80010768                          ;80010044[0C0041DA,'.A..']
  sync                                      ;80010048[0000000F,'....']
;80010768
;
;check recovery boot mode switch
;
	r8 = [$be240004] & 0x10 // GPIO bit 4
;
	r9 = $80010194 // NAND read BLOCK entry
	r10= $80010130 // NAND initialize(read FAT) entry
;
	if(r8!=0)// $80010080
	{
		r9 = $80010248 // rec-dev read BLOCK entry
		r10= $80010240 // rec-dev initialize entry
	}
;80010080
	[$80010808] = r9
	[$8001080c] = 0x000000000
;
;call read FAT
;
	(r10)()
;
	r23 = 0  ; check sum of last block
;
;READ BLOCK LOOP
;
L80010098
	r25 = [$80010808] ; read BLOCK entry
	r4  = [$8001080c] ; block num of read
;
;call read body function
;
	r2 = (r25)(r4,$bfd000000);
	if(r2<0) $80010128
;
;decrypt 1000H block
;
	r2 = $80010620($bfd00000,$bfd00000)
	if(r2<0) $80010128
;
;+000c : check sum of last block ?
;
	if( [$bfd0000c] != r23) $80010128
;
;+0000 : distination address
;+0004 : block size
;
	r4 = [$bfd00000] ; +0000 : top pointer
	r6 = [$bfd00004] ; +0004 : size
	if(r4!=0)
	{
;transmit BLOCK body
		r23 = $80010688(r4,r16 + $10 , r6)
	}
;
;+0008 : entry point or continue MARK check
;
	r25 = r16[8]
	if(r25==0) //$80010114
	{
;L80010114:
		[$8001080c]++  ; next block
		goto $80010098
	}
;
;cache ?
	$800102D8()
;
;cache ?
	$800102A0()
;
;goto IPL entry point
;
	  jalr   r25                                ;8001010C[0320F809,'.. .']
;
;80010128
	while(1); // HALT
;
;---------------------------------------------------------------------------
;read IPL FAT
;---------------------------------------------------------------------------
L80010130:
	r16 =r31
;
;80010134
;NAND reset 
	$80010308()
;
;8001013C
	r17  = $80 // top of IPL-FAT sector
;80010140
;read IPL FAT
	r2 = $80010334(r17,8001081c,80010810)
	if(r2<0) $8001018c
;80010164
	r8 = r6[0]
	r9 = r6[4]
	r10= r6[8]
;ECC signature
	if(r9 != $6dc64a38) // $8001018c
	{
		r17 += $20 // next IPL sector
		goto $80010140
	}
; jr     r16                                ;80010184[02000008,'....']
	return

;------------------------------------------------------------------------
;NAND read body
;
;r4 : fat logical ptr (400H bytes lba? )
;
;------------------------------------------------------------------------
L80010194:
	[$80010800] = r31
	[$80010804] = r4
;
	r17 = r5
;get FAT location
	r8 = $8001081c ; FAT table
	r9 = (r4>>2)<<1
	r8 += r9
	r9 = (u16)r8[0]
;
	r8 = (r9<<2) | (r4 & 3)
;
	r16 = r8 << 3 ; * 8
	r18 = 0
;800101CC
	do
	{
;read body one
		r2 = $80010334(r16+r18,r17 + (r18<<9),80010810)
		if(r2<0) $80010230
		r8 = r6[0]
		r9 = r6[4]
		r10= r6[8]
;ECC signature
		if(r9 != $6dc64a38) $80010230
		r18++
	}while(r18<8);
;80010220
	r31 = [$80010800]
	return r0

L80010230:
	r31 = [$80010800]
	return -1

;------------------------------------------------------------------------
;rec-dev initialize
;------------------------------------------------------------------------
L80010240:
	return $800103B4()

;------------------------------------------------------------------------
;rec-dev read 1000H block
;------------------------------------------------------------------------
L80010248:
	[$80010$800] = r31
;
	r16 = r4
	r17 = r5
	r18 = 0
;8001025C
	do{
		r2 = $80010418(r18+0x10+r16<<3 ,r17 + r18<<9)
		if(r2<0) $8001025c
		r18++
	}while(r18<8);
;
	r31 = [$80010$800]
	return r2

;------------------------------------------------------------------------
;cache ?
;------------------------------------------------------------------------
L800102A0:
  mfc0   r8,Config                          ;800102A0[40088000,'...@']
  addiu  r9,0,$1000                         ;800102A4[24091000,'...$']
  dc.l   $7d081240 [invalid]                ;800102A8[7D081240,'@..}']
  sllv   r9,r9,r8                           ;800102AC[01094804,'.H..']
  mtc0   0,TagLo                            ;800102B0[4080E000,'...@']
  mtc0   0,TagHi                            ;800102B4[4080E800,'...@']
  addu   r8,0,0                             ;800102B8[00004021,'!@..']
;
  cache  $01,r8($0)                         ;800102BC[BD010000,'....']
  cache  $03,r8($0)                         ;800102C0[BD030000,'....']
  addiu  r8,r8,$40                          ;800102C4[25080040,'@..%']
  bne    r8,r9,$800102bc                    ;800102C8[1509FFFC,'....']
  nop                                       ;800102CC[00000000,'....']
  jr     r31                                ;800102D0[03E00008,'....']
  nop                                       ;800102D4[00000000,'....']

;------------------------------------------------------------------------
;cache ?
;------------------------------------------------------------------------
L800102D8:
  mfc0   r8,Config                          ;800102D8[40088000,'...@']
  addiu  r9,0,$800                          ;800102DC[24090800,'...$']
  dc.l   $7d081180 [invalid]                ;800102E0[7D081180,'...}']
  sllv   r9,r9,r8                           ;800102E4[01094804,'.H..']
  addu   r8,0,0                             ;800102E8[00004021,'!@..']
;
  cache  $14,r8($0)                         ;800102EC[BD140000,'....']
  cache  $14,r8($0)                         ;800102F0[BD140000,'....']
  addiu  r8,r8,$40                          ;800102F4[25080040,'@..%']
  bne    r8,r9,$800102ec                    ;800102F8[1509FFFC,'....']
  nop                                       ;800102FC[00000000,'....']
  jr     r31                                ;80010300[03E00008,'....']
  sync                                      ;80010304[0000000F,'....']

;----------------------------------------------------------------------------
;NAND reset CMD
;----------------------------------------------------------------------------
L80010308:
;nand cmd
	[$bd101008] = 0xff
;nand sts
	while( [$bd101004] & 1 ==0);
;
	[$bd101014] = 0x01
	return

;----------------------------------------------------------------------------
;NAND Read Sector
;
;r4 : sector
;r5 : data buffer
;r6 : Extra buffer
;
;----------------------------------------------------------------------------
L80010334:
;nand sts
	while([$bd101004] & 1 == 0);
;
	[$bd101020] = r4 << 10
	[$bd101024] = $301
;80010354
	while([$bd101024] & 1 == 0);
;80010364
	if([$bd101028] != 0) return -1
;
  lui    r8,$bff0                           ;80010370[3C08BFF0,'...<']
;
	r9  = r8[$900]
	r10 = r8[$904]
	r2  = r8[$908]
;
	r6[0] = r9
	r6[4] = r10
	r6[8] = r2
;
	r9 = r5
	r2 = $200
L80010394:
	do
	{
		r10 = r8[0]
		r2 -= 4
		r8 += 4
		r9[0] = r10
		r9 += 4
	}while(r2);
;800103AC
	return 0

;----------------------------------------------------------------------------
;rec-dev initialize
;----------------------------------------------------------------------------
L800103B4:
	r24 = r31
;
;rec-dev I/O init : device & clock enable ?
	$800106B0(L80010ad4)
;
;reset device ?
;
	[$bd20003c] = $8000
;800103D4
	while( [$bd20003c] & 0x8000);
;
	$80010530()
	$80010508()
;
;800103F4
	do{
		r2 = $800105B8()
		if(r2<0) continue // $800103f4
;
	}while(r2 & $0080 == 0); // $800103f4
;
;  jr     r24                                ;80010410[03000008,'....']
	return 0

;----------------------------------------------------------------------------
;rec-dev read sector one
;
;a1:sector address
;a2:buffer
;
;----------------------------------------------------------------------------
L80010418:
	r14 = r5
;	r24 = r31
;  lui    r25,$bd20
;
;read sector COMMAND ?
	[$bd200030] = $00009007
;
  dc.l   $7c0428e0 [invalid]                ;8001042C[7C0428E0,'.(.|']
;
	r5 >>= 8
	r9 = (r4 >> 24) << 24
;
	r4 = $00010020
	r4 |= r9
;
;write parameter
	r2 = $800104C0(r4,r5)
	if(r2<0) return -1
;busy wait
	$80010608()
;
;$8001045c
	do{
		r2 = $800105B8()
		if(r2<0) return -1
		r2 = r2 & $0020
	}while((r2 & $0020)==0);
;
	if(r2 & $0040) return -1
;
;read buffer COMMAND ?
	[$bd200030] = $00002200
;
;read sector data
	r2 = $800104CC(r14,$200) // r14 == r5
	if(r2<0) return -1
;wait finish
	r2 = $80010508()
	if(r2<0) return -1
;busy wait
	$80010608()
;
	goto $800103f4
;
;800104B8
;  jr     r24                                ;800104B8[03000008,'....']
	return -1

;----------------------------------------------------------------------------
;rec-dev : commmand output ?
;
;a1:1st write data
;a2:2nd write data
;----------------------------------------------------------------------------
L800104C0:
	[$bd200034] = r4
	[$bd200034] = r5
	goto $80010508

;----------------------------------------------------------------------------
;rec-dev read data block
;
;a1:distination pointer
;a2:transmit size
;
;----------------------------------------------------------------------------
L800104CC:
	do{
		do{
			r9 = [$bd200038]
			if(r9 & $0100) return -1;
		}while(r9 & $4000 == 0);
;
		r2 = [$bd200034]
		r5 -= 4
		r4[0] = r2
		r4 += 4
	}while(r5 >=0);
;
	return 0;

;----------------------------------------------------------------------------
;wait for TX finish ?
;----------------------------------------------------------------------------
L80010508:
	do{
		r9 = [$bd200038]
	}while(r9 & $1000 == 0);
;
	if(r9 & $0300) return -1// $80010528
;
	return 0

;----------------------------------------------------------------------------
;rec-dev read status ?
;----------------------------------------------------------------------------
L80010530:
;  addu   r15,r31,0                          ;80010530[03E07821,'!x..']
;  lui    r25,$bd20                          ;80010534[3C19BD20,' ..<']
;
	[$bd200030] = $00008004
	[$bd200034] = $06100800
	[$bd200034] = 0
	r2 = $80010508()
	if(r2<0) return -1
;
	$800105A4($80010a1c,8);
;
;get status ?
;
	r4 = [$80010a1c]
	r5 = [$80010a20]
;
	if( (r4>>16)&0x15 != 0) return -1
;
	return 0

;----------------------------------------------------------------------------
;rec-dev read status ?
;
;a1:buffer
;a2:size
;
;----------------------------------------------------------------------------
L800105A4:
	[$bd200030] = $00004000
;read sector body
	return $800104cc(r4,r5)

;-----------------------------------------------------------------------------
;rec-dev device ready check?
;-----------------------------------------------------------------------------
L800105B8:
;r25 = $bd200000
	[$bd200030] = $00007001
;wait
	do
	{
		r9 = [$bd200038]
	}while(r9 & $0100);
	if((r9 & $4000)==0) $800105c0
;
	r2 = [$bd200034]
	r0 = [$bd200034] // ?
;800105E0
	do{
		r9 = [$bd200038]
		if(r9 & $0100) //$80010600
		{
L80010600:
			return -1
		}
	}while( (r9 & $1000)==0);
;
	return r2 & 0xff;

;----------------------------------------------------------------------------
;wait for rec-dev busy
;----------------------------------------------------------------------------
L80010608:
	do
	{
		r9 = [$bd200038]
	}while( (r9 & $2000) == 0);
	return

;-----------------------------------------------------------------------------
;decrypt 1000H block
;-----------------------------------------------------------------------------
L80010620:
;  lui    r25,$bde0                          ;80010620[3C19BDE0,'...<']
;
	[$bde00010] = $00000001
;r8 = r4
  dc.l   $7ca8e000 [invalid]                ;8001062C[7CA8E000,'...|']
	[$bde0002c] = r8
;
;r8 = r5
  dc.l   $7c88e000 [invalid]                ;80010634[7C88E000,'...|']
	[$bde00030] = r8
;
	[$bde0000c] = $00000001
;$80010644
	do{
		r8 = [$bde0001c]
	}while(r8 & $0011 == 0)
;
	[$bde00028] = r8
	if(r8&$0010) // $80010664
	{
L80010664:
		[$bde0000c] = $00000002
;$8001066C
		do{
			r8 = [$bde0001c]
		}while(r8 & $0002 == 0)
;
		[$bde00028] = r8
		sync
		return -1
	}
;
	return [$bde00014]

;----------------------------------------------------------------------------
;transmit data with calc check sum
;
;arg1: source
;arg2: distination
;arg1: size
;
;return : 32bit check sum (add)
;
;----------------------------------------------------------------------------
L80010688:
	r2 = 0 ; clear check sum
	do{
		r3 = r5[0]
		r5 += 4
		r6 -= 4
		r4[0] = r3
		r2 += r3 ; check sum
		r4 += 4
	}while(r6>=0);
	return

;---------------------------------------------------------------------------
;script executer
;
;a1:script pointer
;
;2 word command
;
;+00[31:28] : CMD
;+00[27: 0] : OFFSET
;+04[31: 0] : VALUE
;
;CMD : command :
; 0  : store   | [$b0000000 + OFFSET]  = VALUE
; 1  : or      | [$b0000000 + OFFSET] |= VALUE
; 2  : and     | [$b0000000 + OFFSET] &= VALUE
; 3  : wait toL| while( ( [$b0000000 + OFFSET] &= VALUE) != 0)
;(4) : wait toH| while( (~[$b0000000 + OFFSET] &= VALUE) != 0)
; 5  : delay   | for(cnt=VALUE*96;cnt;cnt--)
; F  : end     | return
;
;---------------------------------------------------------------------------
L800106B0:
	r8 = r4
;addu   r25,r31,0
;
;800106b8
	do{
		// read CMD:offset + VALUE
		r4 = r8[0]
		r9 = r4 >> 28
		r4 = ( (r4 << 4)>>4 ) | $b0000000
		r5 = r4[4]
;
		if(r9==0) //$80010724
		{
;80010724
			r4[0]=r5
			goto $8001071c
		}
		if(r9==1)// $8001072c
		{
;8001072C
			r4[0] = r4[0] | r5
			goto $8001071c
		}
		if(r9==2) // $8001073c
		{
			r4[0] = r4[0] & r5
			goto $8001071c
		}
		r1 = 0
		if(r9==3) $8001074c
;
		r1 = $ffffffff ;  nor    r1,0,0
;!!!!! buggy code !!!!!
;  addiu  r10,r10,-$4
;		if(r9==4) $8001074c
		if(r9==7) $8001074c
;!!!!! buggy code !!!!!

;		if(r9==5) //$80010714
		{
L80010714:
			$80010768(r5);
			goto L8001071C
		}
;default:
;  jr     r25                                ;8001070C[03200008,'.. .']
		return;
;
;case end
L8001071C:
		// next script point
		r8 += 8
	}while(1);
;
;4,7
L8001074C:
	{
		do{
			r9 =  (r4[0] ^ r1) & r5
		}while(r9!=0);
		goto $8001071c
	}

;--------------------------------------------------------------------------
;delay
;--------------------------------------------------------------------------
L80010768:
	r1 = ((r4 << 1) + r4)<<5 // * 96
	while(r1) r1--;
	return

;--------------------------------------------------------------------------
;--------------------------------------------------------------------------
L80010784:
  nop                                       ;80010784[00000000,'....']
  nop                                       ;80010788[00000000,'....']
  nop                                       ;8001078C[00000000,'....']
  nop                                       ;80010790[00000000,'....']
  nop                                       ;80010794[00000000,'....']
  nop                                       ;80010798[00000000,'....']
  nop                                       ;8001079C[00000000,'....']
  nop                                       ;800107A0[00000000,'....']
  nop                                       ;800107A4[00000000,'....']
  nop                                       ;800107A8[00000000,'....']
  nop                                       ;800107AC[00000000,'....']
  nop                                       ;800107B0[00000000,'....']
  nop                                       ;800107B4[00000000,'....']
  nop                                       ;800107B8[00000000,'....']
  nop                                       ;800107BC[00000000,'....']
  nop                                       ;800107C0[00000000,'....']
  nop                                       ;800107C4[00000000,'....']
  nop                                       ;800107C8[00000000,'....']
  nop                                       ;800107CC[00000000,'....']
  nop                                       ;800107D0[00000000,'....']
  nop                                       ;800107D4[00000000,'....']
  nop                                       ;800107D8[00000000,'....']
  nop                                       ;800107DC[00000000,'....']
  nop                                       ;800107E0[00000000,'....']
  nop                                       ;800107E4[00000000,'....']
  nop                                       ;800107E8[00000000,'....']
  nop                                       ;800107EC[00000000,'....']
  nop                                       ;800107F0[00000000,'....']
  nop                                       ;800107F4[00000000,'....']
  nop                                       ;800107F8[00000000,'....']
  nop                                       ;800107FC[00000000,'....']

;-----------------------------------------------------------------------------
;
;r31 save buffer
;
L80010800:
	dl 800100B0

;
;r4 save buffer
;
L80010804:
	dl 0000002E
;
;read sector function entry
;
L80010808:
	dl L80010194
;
;read block number
;
L8001080C:
	dl L0000002E
;
;NAND Extra buffer
;
L80010810:
	dl	FFFFFFFF
	dl	6DC64A38
	dl	FFFFFD89

;
;NAND Data buffer (IPL FAT)
;
L8001081c
  mfhi   0                                  ;8001081C[00110010,'....']
  mflo   0                                  ;80010820[00130012,'....']
  dsllv  0,r21,0                            ;80010824[00150014,'....']
  dsrlv  0,r23,0                            ;80010828[00170016,'....']
  mult   0,r25                              ;8001082C[00190018,'....']
  div    0,r27                              ;80010830[001B001A,'....']
  nop                                       ;80010834[00000000,'....']
  nop                                       ;80010838[00000000,'....']
  nop                                       ;8001083C[00000000,'....']
  nop                                       ;80010840[00000000,'....']
  nop                                       ;80010844[00000000,'....']
  nop                                       ;80010848[00000000,'....']
  nop                                       ;8001084C[00000000,'....']
  nop                                       ;80010850[00000000,'....']
  nop                                       ;80010854[00000000,'....']
  nop                                       ;80010858[00000000,'....']
  nop                                       ;8001085C[00000000,'....']
  nop                                       ;80010860[00000000,'....']
  nop                                       ;80010864[00000000,'....']
  nop                                       ;80010868[00000000,'....']
  nop                                       ;8001086C[00000000,'....']
  nop                                       ;80010870[00000000,'....']
  nop                                       ;80010874[00000000,'....']
  nop                                       ;80010878[00000000,'....']
  nop                                       ;8001087C[00000000,'....']
  nop                                       ;80010880[00000000,'....']
  nop                                       ;80010884[00000000,'....']
  nop                                       ;80010888[00000000,'....']
  nop                                       ;8001088C[00000000,'....']
  nop                                       ;80010890[00000000,'....']
  nop                                       ;80010894[00000000,'....']
  nop                                       ;80010898[00000000,'....']
  nop                                       ;8001089C[00000000,'....']
  nop                                       ;800108A0[00000000,'....']
  nop                                       ;800108A4[00000000,'....']
  nop                                       ;800108A8[00000000,'....']
  nop                                       ;800108AC[00000000,'....']
  nop                                       ;800108B0[00000000,'....']
  nop                                       ;800108B4[00000000,'....']
  nop                                       ;800108B8[00000000,'....']
  nop                                       ;800108BC[00000000,'....']
  nop                                       ;800108C0[00000000,'....']
  nop                                       ;800108C4[00000000,'....']
  nop                                       ;800108C8[00000000,'....']
  nop                                       ;800108CC[00000000,'....']
  nop                                       ;800108D0[00000000,'....']
  nop                                       ;800108D4[00000000,'....']
  nop                                       ;800108D8[00000000,'....']
  nop                                       ;800108DC[00000000,'....']
  nop                                       ;800108E0[00000000,'....']
  nop                                       ;800108E4[00000000,'....']
  nop                                       ;800108E8[00000000,'....']
  nop                                       ;800108EC[00000000,'....']
  nop                                       ;800108F0[00000000,'....']
  nop                                       ;800108F4[00000000,'....']
  nop                                       ;800108F8[00000000,'....']
  nop                                       ;800108FC[00000000,'....']
  nop                                       ;80010900[00000000,'....']
  nop                                       ;80010904[00000000,'....']
  nop                                       ;80010908[00000000,'....']
  nop                                       ;8001090C[00000000,'....']
  nop                                       ;80010910[00000000,'....']
  nop                                       ;80010914[00000000,'....']
  nop                                       ;80010918[00000000,'....']
  nop                                       ;8001091C[00000000,'....']
  nop                                       ;80010920[00000000,'....']
  nop                                       ;80010924[00000000,'....']
  nop                                       ;80010928[00000000,'....']
  nop                                       ;8001092C[00000000,'....']
  nop                                       ;80010930[00000000,'....']
  nop                                       ;80010934[00000000,'....']
  nop                                       ;80010938[00000000,'....']
  nop                                       ;8001093C[00000000,'....']
  nop                                       ;80010940[00000000,'....']
  nop                                       ;80010944[00000000,'....']
  nop                                       ;80010948[00000000,'....']
  nop                                       ;8001094C[00000000,'....']
  nop                                       ;80010950[00000000,'....']
  nop                                       ;80010954[00000000,'....']
  nop                                       ;80010958[00000000,'....']
  nop                                       ;8001095C[00000000,'....']
  nop                                       ;80010960[00000000,'....']
  nop                                       ;80010964[00000000,'....']
  nop                                       ;80010968[00000000,'....']
  nop                                       ;8001096C[00000000,'....']
  nop                                       ;80010970[00000000,'....']
  nop                                       ;80010974[00000000,'....']
  nop                                       ;80010978[00000000,'....']
  nop                                       ;8001097C[00000000,'....']
  nop                                       ;80010980[00000000,'....']
  nop                                       ;80010984[00000000,'....']
  nop                                       ;80010988[00000000,'....']
  nop                                       ;8001098C[00000000,'....']
  nop                                       ;80010990[00000000,'....']
  nop                                       ;80010994[00000000,'....']
  nop                                       ;80010998[00000000,'....']
  nop                                       ;8001099C[00000000,'....']
  nop                                       ;800109A0[00000000,'....']
  nop                                       ;800109A4[00000000,'....']
  nop                                       ;800109A8[00000000,'....']
  nop                                       ;800109AC[00000000,'....']
  nop                                       ;800109B0[00000000,'....']
  nop                                       ;800109B4[00000000,'....']
  nop                                       ;800109B8[00000000,'....']
  nop                                       ;800109BC[00000000,'....']
  nop                                       ;800109C0[00000000,'....']
  nop                                       ;800109C4[00000000,'....']
  nop                                       ;800109C8[00000000,'....']
  nop                                       ;800109CC[00000000,'....']
  nop                                       ;800109D0[00000000,'....']
  nop                                       ;800109D4[00000000,'....']
  nop                                       ;800109D8[00000000,'....']
  nop                                       ;800109DC[00000000,'....']
  nop                                       ;800109E0[00000000,'....']
  nop                                       ;800109E4[00000000,'....']
  nop                                       ;800109E8[00000000,'....']
  nop                                       ;800109EC[00000000,'....']
  nop                                       ;800109F0[00000000,'....']
  nop                                       ;800109F4[00000000,'....']
  nop                                       ;800109F8[00000000,'....']
  nop                                       ;800109FC[00000000,'....']
  nop                                       ;80010A00[00000000,'....']
  nop                                       ;80010A04[00000000,'....']
  nop                                       ;80010A08[00000000,'....']
  nop                                       ;80010A0C[00000000,'....']
  nop                                       ;80010A10[00000000,'....']
  nop                                       ;80010A14[00000000,'....']
  nop                                       ;80010A18[00000000,'....']
;
;rec-dev status read buffer ?
L80010A1C:
	dl	00000000,00000000
;
  nop                                       ;80010A24[00000000,'....']
  nop                                       ;80010A28[00000000,'....']
  nop                                       ;80010A2C[00000000,'....']
  nop                                       ;80010A30[00000000,'....']
  nop                                       ;80010A34[00000000,'....']
  nop                                       ;80010A38[00000000,'....']
  nop                                       ;80010A3C[00000000,'....']
  nop                                       ;80010A40[00000000,'....']
  nop                                       ;80010A44[00000000,'....']
  nop                                       ;80010A48[00000000,'....']
  nop                                       ;80010A4C[00000000,'....']
  nop                                       ;80010A50[00000000,'....']
  nop                                       ;80010A54[00000000,'....']
  nop                                       ;80010A58[00000000,'....']
  nop                                       ;80010A5C[00000000,'....']
  nop                                       ;80010A60[00000000,'....']
  nop                                       ;80010A64[00000000,'....']
  nop                                       ;80010A68[00000000,'....']
  nop                                       ;80010A6C[00000000,'....']
  nop                                       ;80010A70[00000000,'....']
  nop                                       ;80010A74[00000000,'....']
  nop                                       ;80010A78[00000000,'....']
  nop                                       ;80010A7C[00000000,'....']
;
;
;script command : I/O init
;
L80010A80:
	dl	1C100058,00800000	; [$bc100058] |= 00800000
	dl	1C100050,0000608E	; [$bc100050] |= 0000608E
	dl	2C10004C,FFFFFBF7	; [$bc10004C] &= FFFFFBF7
	dl	1C100078,00000002	; [$bc100078] |= 00000002
	dl	2E240000,FFFFFFEF	; [$be240000] &= FFFFFFEF : GPIO bit4 direction read?
	dl	1E240040,00000010	; [$be240040] |= 00000010 : GPIO bit4 pullup enable ?
	dl	50000000,00000001	; delay 1
	dl	0D500010,00000001	; [$bd500010] = 00000001
	dl	3D500010,00000001	; while( [$bd500010] & 1)
	dl	0D500040,00000001	; [$bd500040] = 00000001
	dl	F0000000			; end
;
;script command : rec-dev I/O init
;
L80010AD4:
	dl	3D500010,00000001	; while( [$bd500010] & 1)
	dl	1C100054,00000100	; [$bc100054] |= 00000100
	dl	1C100050,00000400	; [$bc100050] |= 00000400
	dl	1C100078,00000010	; [$bc100078] |= 00000010
	dl	2C10004C,FFFFFEFF	; [$bc10004C] &= FFFFFEFF
	dl	F0000000			; end
;
;------------------------------------------------------------------------------
;code end
;------------------------------------------------------------------------------

PSVita Compatibility mode behavior

PRE-IPL is sent by the compatibility secure module (os0:sm/compat_sm.self) to the non-secure kernel which writes it to 0xE8100000 (named CompatSharedSram and mapped to the 0xBFC00000 reset vector on the emulated PSP/Tachyon side).

compat_sm will then send a specific 0x40 bytes key to be used for by the PSVita's PRE-IPL as a 0x40 bytes XOR mask against the IPL header (the IPL is stored in the pcbc.skprx kernel module).

KIRK command 1 will then be used on the result. Unlike on actual PSP units, the IPL is decrypted in a single large block rather than in multiple blocks.

The 0x40 bytes key gets updated depending on the firmware version in use.

A 0x40 bytes XOR mask is also presumably how the PSP-3000 (and newer), as well as the 3.50+ DTP-T1000 security, is most likely handled (see PSP PRE-IPL section).

Dumper

As of March 21st 2018, a dumper for DTP-T1000 PRE-IPL has been made available on github by mathieulh:

See also