KBL Param

The sysroot buffer is a 0x100 or 0x200 sized buffer passed to the secure kernel bootloader in the scratch space and contains all sorts of flags and system parameters. This buffer is copied to the secure kernel, the non-secure kernel loader, and the non-secure kernel and is used by many functions to check for features that are enabled for the system.

Offset	Size	Description
0x0	0x2	Version (usually 1)
0x2	0x2	Sysroot size (0x100 or 0x200)
0x4	0x4	Current Firmware Version
0x8	0x4	Factory Firmware Version
0xC	0x14	unk
0x20	0xC	QA flags
0x2C	0x8	Bitfield Flags
0x34	0xC	unk (ex: on production models 0xFFFF, on a prototype DEM H unit with fw 0.945 always 0xFEFF, on PSTV 0xFEFF)
0x40	0x4	Devkit CP timestamp 1
0x44	0x2	Devkit CP Version
0x44	0x2	Devkit CP Build ID
0x48	0x4	Devkit CP timestamp 2
0x4C	0x4	ASLR Seed
0x50	0x4	DevKit Boot Parameters (ex: 0x80000000 or 0x80000001 or 0x80000003 or 0x81000000 or 0x81000001 OR 0x0 or 0x2 in release mode)
0x54	0x4	unk (seams to be always 0)
0x58	0x4	Devkit unk flags (ex: 00 00 00 00 retail, E7 53 14 00 development mode, 20 00 08 00 release mode)
0x5C	0x4	Devkit Flags 3 (ex: 0x0 retail, 0x20000010 dev mode, 0x20000000 release mode)
0x60	0x4	DRAM base paddr
0x64	0x4	DRAM size
0x68	0x4	unk
0x6C	0x4	Boot type indicator (0x20000 on resume - no boot logo, 0x1 on boot - boot logo)
0x70	0x10	OpenPsId
0x80	0x4	secure_kernel.enp raw data paddr (optional)
0x84	0x4	secure_kernel.enp size (optional)
0x88	0x8	unk
0x90	0x4	kprx_auth_sm.self raw data paddr
0x94	0x4	kprx_auth_sm.self size
0x98	0x4	prog_rvk.srvk raw data paddr
0x9C	0x4	prog_rvk.srvk size
0xA0	0x8	PSCode
0xA8	0x8	unk
0xB0	0x10	Session ID
0xC0	0x4	unk
0xC4	0x4	Boot type indicator (0x80 on resume)
0xC8	0x8	unk (0x40 on retail and testkit, 0x64 on devkit, 0xC001C0 on a prototype DEM H unit)
0xD0	0x4	Saved context paddr
0xD4	0x4	Hardware info
0xD8	0x4	Boot type indicator 3
0xDC	0x1C	unk
0xF8	0x4	BootLoader Revision
0xFC	0x4	Sysroot Magic value (0xCBAC03AA)
0x100	0x20	Encrypted Session Key (FW 2.12+)

Boot type indicator 3

Experimental point of view

No AC connected + No POWER Button pressed: 0x0 (ex: rebooting by software PSVita when AC is not connected)
No AC connected + POWER Button pressed: 0x4 (Booting PSVita by pressing POWER button when AC is not connected)
AC connected + No POWER Button pressed: 0x8 (ex: rebooting by software PSVita when AC is connected, autobooting PSTV/IDU PSVita by pluging AC)
AC connected + POWER Button pressed: 0xC (ex: powering off PSTV by software then booting it by pressing POWER button)

Bit flags point of view

Bit	Description
0	AC: connected: 1 - disconnected: 0
1	POWER button: pressed: 1 - not pressed: 0

Bitfield Flags

Flags

At offset 0x2C there is a 8 byte flags field.

Bit	Description
29	Set to skip version checks in system updates

DIP Switches

To convert the bit number to the offset and bit: offset = 0x40 + (bit_num / 32) * 4, bit = 1 << (bit_num % 32)

CP Information

Bits 0-31 is a 32-bit integer of the current time on the devkit CP clock. This is duplicated in bits 64-95.

Bits 32-47 is a 16-bit integer of the CP version and bits 48-63 is a 16-bit integer of the CP build ID. All integers are little-endian.
On non-devkits, these fields are zero. Bits 0-63 are also usable as general purpose switches exposed with sceKernelSetDipsw, sceKernelClearDipsw, and sceKernelCheckDipsw but they do not change anything in hardware (only cached values are overwritten).

User Flags

Bits 96-127 does not seem to be used in the kernel.

DevKit Boot Parameters

Bits 128-159 are used to store DevKit flags. It does not appear to be used in other models.

Bit	Description
152	PS TV Emulation: On: 1 - Off: 0
159	Release Check Mode: Development Mode: 1 - Release Mode: 0
?	Memory Size: Console Size: 1 - Development Tool Size: 0

Shell Flags

Bits 160-191 are used for SceShell flags.

Bit	Description

Debug Flags

Bits 192-223 are for various debugging options.

Bit	Description
197	Enable kernel console logging
211	Enable user UART console logging

System Flags

Bits 224-255 are used for various system options.

Bit	Description
229	HDCP related?