KBL Param

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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 0x10 QA flags
0x30 0x10 Boot flags
0x40 0x20 DIP Switches
0x60 0x4 DRAM base paddr (0x40000000)
0x64 0x4 DRAM size (0x20000000 on retail and testkit, 0x40000000 on DevKit)
0x68 0x4 unk
0x6C 0x4 Boot type indicator 1 (0x20000 on resume - no boot logo, 0x1 on boot - boot logo, 0x4 manufacturing mode)
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 Wakeup factor
0xC8 0x4 unk (?Device model dependant?) (ex: 0x40, 0x60, 0x64, 0x3D2, 0xC001C0)
0xCC 0x4 unk (0x74FFFFFF on coldboot, 0x74FFBFFF on warmboot)
0xD0 0x4 Saved context paddr
0xD4 0x4 Hardware info
0xD8 0x4 Boot type indicator 2
0xDC 0xC unk
0xE8 0x10 Hardware flags
0xF8 0x4 BootLoader Revision
0xFC 0x4 Sysroot Magic value (0xCBAC03AA)
0x100 0x20 Encrypted Session Key (FW 2.12+)

QA flags

Bit Description
0x2C + bit 29 Set to skip version checks in system updates
0x2D + bit 30 Checked by SceAppMgr. Dictates if you can pass arguments to sceAppMgrLaunchAppByPathForDriver

Boot flags

Bit Description
47 use internal storage
  • at 0x30: 0xFF - not update mode
  • at 0x33: 0xFF - not safe mode
  • at 0x35: FF on FAT - no internal storage or on PSTV or SLIM - internal storage enabled, FE on PSTV or SLIM - internal storage disabled

Hardware Info

Data is returned by SceSyscon.

  • 00 60 41 00: PDEL-1XXX
  • 00 60 40 00: PCH-10XX / PTEL-1XXXX
  • 02 60 40 00: PCH-11XX
  • 38 22 82 00: PCH-2XXX model revision 0x18
  • 30 30 70 00: VTE-XXXX

Bit flags

Bit Description
2 PSTV Slim
3 PSTV Slim
4 Slim
6 3G Modem
9 Fat
10 always set
11 PSTV
16 Slim
17 PSTV Fat
18 PSTV
19 PSTV
22 Slim
23 ?Communication Processor?

Boot type indicator 2

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
ex: 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
ex: autobooting PSTV/IDU PSVita by pluging AC

- AC connected + POWER Button pressed: 0xC
ex: powering off by software PSTV then booting it by pressing POWER button
ex: booting PSVita by pressing POWER button when AC is connected

Bit flags point of view

Bit Description
0 AC: connected: 1 - disconnected: 0 (note that PSTV always has AC connected)
1 POWER button: pressed: 1 - not pressed: 0

Wakeup factor

  • 14 FF 00 00
  • 04 FF 00 00 after normal reboot
  • 04 00 00 00
  • 00 FF 00 00
  • 80 after suspend

DIP Switches

Offset Size Description
0x40 0x4 DevKit CP timestamp 1
0x44 0x2 DevKit CP Version
0x46 0x2 DevKit CP Build ID
0x48 0x4 DevKit CP timestamp 2 (strangely also set on Retail and TesKit)
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 DevKit Shell flags
0x58 0x4 DevKit Debug flags (ex: 0x1453E7 dev mode, 0x080002 release mode)
0x5C 0x4 DevKit System flags 3 (ex: 0x20000010 dev mode, 0x20000000 release mode)

DIP Switches Bit flags resolving

DIP Switches bit flags are numbered from right to left. Thus, we have to use an algorithm to convert bit number to offset and bit.

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 zeroes. 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.

Bit Description
152 PS TV Emulation: On: 1 - Off: 0
159 Release Check Mode: Development Mode: 1 - Release Mode: 0
168 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?

Hardware flags

Bit Description
1 IC Connexant: 1 - yes, 2 - no
5 unk
6 unk
7 unk
14 unk
  • all zeroes on most cases
  • 47 02 on a Slim

Types

typedef struct SceBootArgs {
  uint16_t version;
  uint16_t size;
  uint32_t fw_version;
  uint32_t ship_version;
  uint8_t unk_C[0x14];
  uint8_t qa_flags[0x10];
  uint8_t boot_flags[0x10];
  uint32_t devkit_cp_timestamp_1;
  uint16_t devkit_cp_version;
  uint16_t devkit_cp_build_id;
  uint32_t devkit_cp_timestamp_2;
  uint32_t aslr_seed;
  uint32_t devkit_boot_parameters;
  uint32_t unk_54;
  uint32_t devkit_unk_flags;
  uint32_t devkit_flags_3;
  uint32_t dram_base;
  uint32_t dram_size;
  uint32_t unk_68;
  uint32_t boot_type_indicator_1;
  uint8_t openpsid[0x10];
  uint32_t secure_kernel_enp_addr;
  uint32_t secure_kernel_enp_size;
  uint8_t unk_88[0x8];
  uint32_t kprx_auth_sm_self_addr;
  uint32_t kprx_auth_sm_self_size;
  uint32_t prog_rvk_srvk_addr;
  uint32_t prog_rvk_srvk_size;
  uint8_t pscode[0x8];
  uint8_t unk_A8[0x8];
  uint8_t session_id[0x10];
  uint32_t unk_C0;
  uint32_t wakeup_factor;
  uint32_t unk_C8;
  uint32_t unk_CC;
  uint32_t resume_context_addr;
  uint32_t hardware_info;
  uint32_t boot_type_indicator_2;
  uint8_t unk_DC[0xC];
  uint8_t hardware_flags[0x10];
  uint32_t bootldr_revision;
  uint32_t magic;
  uint8_t session_key[0x20];
  uint8_t unused[0xE0];
} __attribute__((packed)) SceBootArgs;
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