KBL Param

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The KBL Param buffer (temporary name was sysroot buffer) is a 0x100 or 0x200 bytes sized buffer passed to the Secure Kernel BootLoader in the scratch space and contains all sorts of flags and system parameters. This buffer is created in Second Loader copied to Secure Kernel, passed to the Secure and Non-Secure Kernel BootLoaders, and finally to the non-secure kernel. It is used by many functions to check for features that are enabled for the system. The strategy in this buffer is to compute once for all the information that is often used, to share it between all security layers not to have to implement generator code many times, and to implement the generation code in the most secure layer: second_loader (excluding first_loader but that's because first_loader is not updatable and has minimum code).

Structure

Offset Size Set by Description
0x0 0x2 second_loader Version (usually 1)
0x2 0x2 second_loader Size. Size of this structure. 0x100 or 0x200
0x4 0x4 second_loader Current Firmware Version
0x8 0x4 second_loader Minimum Firmware Version. Comes from SMI IdStorage leaf.
0xC 0x4 Unknown Unknown
0x10 0x4 Unknown Used for Kit Activation. If lower than 0x20, the Kit is fake activated (License Status = 0, Issue No = 0, Expire Date = 0xffffffff). If lower than 0x30, default bus error handler is not registered in SceKernelBusError.
0x14 0xC Unknown maybe unused
0x20 0x10 second_loader QA flags
0x30 0x10 second_loader Boot flags
0x40 0x20 second_loader DIP Switches
0x60 0x4 second_loader DRAM base paddr (0x40000000)
0x64 0x4 second_loader DRAM size (0x20000000 on retail and testkit, 0x40000000 on DevKit in DevKit Memory Size mode)
0x68 0x4 Unknown unk
0x6C 0x4 second_loader Boot type indicator 1
0x70 0x10 second_loader OpenPsId
0x80 0x4 second_loader secure_kernel.enp raw data paddr (optional)
0x84 0x4 second_loader secure_kernel.enp size (optional)
0x88 0x4 second_loader context_auth_sm.self raw data paddr
0x8C 0x4 second_loader context_auth_sm.self size
0x90 0x4 second_loader kprx_auth_sm.self raw data paddr
0x94 0x4 second_loader kprx_auth_sm.self size
0x98 0x4 second_loader prog_rvk.srvk raw data paddr
0x9C 0x4 second_loader prog_rvk.srvk size
0xA0 0x8 second_loader PsCode
0xA8 0x4 second_loader __stack_chk_guard. Set by Second Loader to a pseudo random number. Exported by SceSysmem as __stack_chk_guard.
0xAC 0x4 second_loader Unknown. Set by Second Loader to a pseudo random number.
0xB0 0x10 second_loader Session ID
0xC0 0x4 second_loader Maybe Sleep Factor. Used by sceSysrootIsUsbEnumWakeup, comes from syscon cmd 3 (ex: 1 bsod reboot (or other serious factors), 0x10 bsod poweroff, 0x400 usually, 0x20000 unknown)
0xC4 0x4 second_loader Wakeup Factor
0xC8 0x4 second_loader Unknown, contains USB info, comes from syscon cmd 0x800 (?Device model dependant?) (ex: 0x40 PSVita usually, 0x60 PSTV usually, 0x64 DEM-3000H, 0x1C0 PC USB -> charge USB on FAT, 0x2D2 PC USB -> USB -> charge USB on FAT, 0x2D3 charge USB on FAT, 0x3D2, 0xC001C0 USB charge on SLIM, 0xC503D2 USB charge on SLIM, 0xC501CA USB data to PC)
0xCC 0x4 second_loader Unknown, contains controls info, comes from syscon cmd 0x100 (ex: 0x74FFFFFF on coldboot, 0x74FFBFFF on warmboot, 0x36AFFFXX triggers SetProductMode on 0.940, 0x00FF0000 triggers SetProductMode on 0.995)
0xD0 0x4 second_loader Saved context paddr, comes from syscon cmd 0x90 offset 0xC
0xD4 0x4 second_loader Hardware Info, comes from syscon cmd 5
0xD8 0x4 second_loader Boot type indicator 2
0xDC 0x4 Unknown unk
0xE0 0x4 second_loader, SceDriverTzs If resume, always 0 (second_loader).
0xE4 0x4 Unknown unk
0xE8 0x10 second_loader Hardware flags, comes from syscon cmd 6
0xF8 0x4 second_loader BootLoader Revision
0xFC 0x4 Unknown Sysroot Magic value (0xCBAC03AA)
0x100 0x20 second_loader Coredump Encrypted Session Key (FW 2.12+)

QA flags

In the following table bytes are counted from left to right and bits from left to right too (little-endian). However the OS uses bit masking for QA flags (unlike bit shifting for DIP Switches).

Byte (0-0xF) - mask = 1 << (bit_no & 7) Description Used in
Byte 0x6 - mask 2 Allow ScreenShot Always, Np Full Test, Limited Debug Menu Display Shell, Settings
Byte 0x9 - mask 0x1 Used on 0.931 by SceSblACMgrForKernel_F7524073
Byte 0xB - mask 0x4 kprx_auth_sm
Byte 0xB - mask 0x10 Bypass platform (TEST/TOOL/special CEX) requirement for fSELF with attribute 128 loading secure_kernel
Byte 0xC - mask 2 Allow All Debug Menu Display Settings
Byte 0xC - mask 4 Skip version checks in system updates, Allow DevKit PspEmu Updater, compat_sm
Byte 0xD - mask 1 Allow Kernel Debug (NSKBL logging level set to 0 instead of 1/2, 1 instead of 2), CMeP Debug, USB Enum Wake Up Debug Menu secure_kernel, most NS and S kernel modules
Byte 0xD - mask 2 Allow Remote Sysmodule Load (host0:), Dictates if you can pass arguments to sceAppMgrLaunchAppByPathForDriver secure_kernel, SceAppMgr
Byte 0xE - mask 1 Allow Remote SM and Kernel module Load (host0:), Allow ASLR Disable, Force Load Kernel Module in NSKBL (loop until success) second_loader, secure_kernel, NSKBL
Byte 0xF - mask 1 Allow NonQA Pup, Minimum Debug Menu Display secure_kernel, update_service_sm, Updater, Settings
Byte 0xF - mask 2 unknown update_service_sm

To check: Byte 0xF bit 7, byte 0xE bit 7, byte 0xE bit 6, byte 0xB bit 3: Revocation related.

The data below contains QA Flags captured (at 0x20 in KBL Param) from a System Debugger unit (SD DEM): 

Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
00000020  33 00 00 00 00 00 07 05 73 01 00 01 06 03 03 01  3.......s.......

Boot flags

These Boot flags come from Ernie NVS and Ernie SNVS.

On FW 3.60, second_loader generates the boot flags as following:

  • byte 0 = NVS 0x4A0 byte 0
  • byte 1 = SNVS 0x480 byte 1
  • byte 2 = 0
  • byte 3 = SNVS 0x480 byte 3
  • byte 4 = SNVS 0x480 byte 7
  • byte 5 = SNVS 0x480 byte 6
  • byte 6-0xF = 0

Example: FF FF 00 FF FF FF 00 00 00 00 00 00 00 00 00 00

Bit Description
47 use internal storage
  • byte 0: 0xFF - not update mode
  • byte 1: 0xFF - extra UART not enabled
  • byte 3: 0xFF - not safe mode
  • byte 4: 0xFF - unknown, maybe not used on FWs <= 0.995
  • byte 5: 0xFF on FAT - no internal storage or on PSTV or SLIM - internal storage enabled, 0xFE on PSTV or SLIM - internal storage disabled, maybe not used on FWs <= 0.995

DIP Switches

DIP switches area embeds two parts: Communication Processor information as 32-bit integers, followed by DIP switches stored as bit flags.

Offset Size Description
0x40 0x4 CP Timestamp 1 (ex: 0x4AD86AB3 -> 16/10/2009 14:44:35)
0x44 0x2 CP Version (ex:0x1301 => 1301 on PDEL-100x)
0x46 0x2 CP Board ID (3 on DEM-300xH, 4 on PDEL-100x)
0x48 0x4 CP Timestamp 2 (identical as CP Timestamp 1)
0x4C 0x4 ASLR Seed (?USER flags?) (also set on Retail and TestKit) (ex: 0x00000000 on a DEM-300xH)
0x50 0x4 SDK (SCE) flags (ex: 0x80000000, 0x80000001, 0x80000003, 0x81000000, 0x81000001, 0, 2)
0x54 0x4 Shell flags (ex: 0x00000000 on a DEM-300xH)
0x58 0x4 Debug control flags (ex: 0x000413E7 on a DEM-300xH, 0x001453E7 dev mode, 0x00080002 release mode)
0x5C 0x4 System control flags (ex: 0x2000001C on a DEM-300xH, 0x20000010 dev mode, 0x20000000 release mode)

DIP Switches bit flags resolving

Warning: DIP Switches bit flags actually start at offset 0x10 (before that is CP information), which implies the first bit flag number is 128 (bit_num = offset / 8).

DIP Switches bit flags follow little-endian logic, which makes it hard to visualize in commonly used big-endian hexadecimal:

  • ((uint32_t *)kbl_param->dipsw[0x10])[0] = 0x00000001 (big-endian in hex) = 01 00 00 00 (little-endian in hex) = 10000000 00000000 00000000 00000000 (little-endian in base 2) <- the 1 corresponds to bit flag number 128
  • ((uint32_t *)kbl_param->dipsw[0x10])[0] = 0x00000002 (big-endian in hex) = 02 00 00 00 (little-endian in hex) = 01000000 00000000 00000000 00000000 (little-endian in base 2) <- the 1 corresponds to bit flag number 129
  • ((uint32_t *)kbl_param->dipsw[0x10])[0] = 0x00000100 (big-endian in hex) = 00 01 00 00 (little-endian in hex) = 00000000 10000000 00000000 00000000 (little-endian in base 2) <- the 1 corresponds to bit flag number 136
  • ((uint32_t *)kbl_param->dipsw[0x10])[0] = 0x80000000 (big-endian in hex) = 00 00 00 80 (little-endian in hex) = 00000000 00000000 00000000 00000001 (little-endian in base 2) <- the 1 corresponds to bit flag number 159

As you can see this way is not convenient to know in memory on which byte corresponds which bit flag, so instead we can use a formula to convert bit number to offset and bit: offset = (bit_num / 32) * 4, bit = bit_num & 31. This is used for example in the following code: 

SceBool sceKernelCheckDipswForDriver(SceUInt32 no) {
  return (*(SceUInt32 *)(kbl_param->dipsw + (no >> 5) * 4) >> (no & 31)) & 1;
}

CP Information

Bits 0-31 is a 32-bit integer of the current time on the 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 board ID. All integers are little-endian. On units that do not have a CP, these fields are zeroes.

Bits 96-127 is 32-bit integer ASLR seed that is randomized on each boot in second loader. It can be disabled by setting a specific DIP switch or QA flag byte 0xE mask 1.

Bits 0-63 are also manipulable as general purpose DIP Switches exposed with sceKernelSetDipsw, sceKernelClearDipsw, and sceKernelCheckDipsw but these functions do not change anything in hardware (only cached values are overwritten in SceSysmem).

According to SDK only DIP Switches 0-63 are accessible from usermode, however:

  • On FW 0.990 (but not on FW 0.931 nor 3.60), DIP Switch number 237 is the only one out of range 0-63 that can be set from usermode.
  • Usermode SELFs can use DIP Switches number > 63 if they have a special attribute or capability in SELF Auth Info.

SDK (SCE) flags

Bits 128-159 are used for DevKit Boot Parameters.

Bit Name Description
128 memory_size_switch Memory Size. (Extended game memory) On: 1 - Off: 0
129 release_check_mode_console Release Mode Console. On: 1 - Off: 0
152 platform_emulation_dolce PS TV Emulation. On: 1 - Off: 0
159 development_mode Release Check Mode. Development Mode: 1 - Release Mode: 0

Shell flags

Bits 160-191 are used for SceShell flags.

Bit Name Description
168 Memory Size: Console Size: 1 - Development Tool Size: 0
184 enable_extra_tty Enable extra TTY: On: 1 - Off: 0. (tty7:)
185 Enable System Boot Time Notifications: On: 1 - Off: 0
187 Allow processes to run on all cores (CPU affinity): On: 1 - Off: 0

Debug control flags

Bits 192-223 are for various debug options.

Bit Description
192 ?
193 Enable SDbgSdio, deci4p_sdfmgr, deci4p_sttyp
194 Enable CP (if disabled it disables Cpup, DbgSdio and UsbDbg)
195 Disable USB Debug. nouse_dbgusb (if enabled, SceUsbDbg doesn't init)
196 Enable kernel UART console logging (if enabled, UART is initialized and SceDebug handlers are set to UART functions).
197 Enable kernel console logging: On: 1 - Off: 0
199 Enable TTY stdio ("tty0:"): On: 1 - Off: 0
200 Stop when an assertion fails: On: 1 - Off: 0
201 Set minimum assertion level to 1: On: 1 - Off: 0. Used in SceSysmem.
202 Set minimum assertion level to 2: On: 1 - Off: 0. Used in SceSysmem.
204 Set minimum log level to 1: On: 1 - Off: 0. Used in NSKBL and SceSysmem.
205 Set minimum log level to 2: On: 1 - Off: 0. Used in NSKBL and SceSysmem.
210 Allow Kernel Budget (related to memblock types)
211 Enable usermode UART console logging?
212 ? Used in NSKBL. Works with dipsw 213.
213 ? Used in NSKBL. Works with dipsw 212.
214 Disable ASLR.
215 Maybe Enable DECI4P SystemDebugger process Trace.
216 Wipe SceKernelBootStackCore0 in NSKBL: On: 1 - Off: 0. Used on FW 0.990 by functions SceThreadmgrForKernel_CA84C603 and SceThreadmgrForKernel_05F5306C and on FW 3.60 by NSKBL.

System control flags

Bits 224-255 are used for various system options.

Bit Description
224 Allows loading sd0:psp2-config.txt
225 Used in NSKBL when doing something with exception stacks
228 Allows getting and setting Process and Thread HBP and HWP. sceKernelGetPHWPForKernel, sceKernelSetPHWPForKernel, sceKernelGetPHBPForKernel, sceKernelSetPHBPForKernel, sceKernelGetTHBPForDriver, sceKernelSetTHBPForDriver.
229 HDCP related?
231 used by SceIofilemgr
232 ? Used in second_loader. DIP Switches 232, 240 and 241 are related.
236 GPU overclock. When enabled, GPU and GPU Xbar are overclocked from 111MHz to 166MHz.
237 On FW 0.990 (but not on FW 0.931 nor 3.60), this is the only DIP switch out of range 0-63 that can be set from usermode.
238 Underclock. When enabled, something is underclocked from 222MHz to 111MHz.
239 Underclock/overclock related.
240 ? Used in second_loader. DIP Switches 232, 240 and 241 are related.
241 Disable QA flags 0xD mask 1 and 0xE mask 1. Used in second_loader. DIP Switches 232, 240 and 241 are related.
250 Enable "tty0:"
251 Enable "dummytty0:"
252 ? Used in SceSblFwLoader.
253 Enable some console logging: On: 1 - Off: 0. Used in NSKBL.

if ((System control flags & 1) != 0) { // not allow load QA flag } else { // allow load QA flag }

if ((System control flags & 2) != 0) { // clear qa flags // (SceQafMgrForDriver_382C71E8, SceQafMgrForDriver_52B4E164, sceSblQafMgrIsAllowHost0Access and sceSblQafMgrIsAllowDecryptedBootConfigLoad functions will return false) }

Boot type indicator 1

We ignore the official name so we name it Boot type indicator 1.

  • 0x1: external boot mode. It is used in internal FWs to boot in external mode. It cannot be set in external (release) second_loader.
  • 0x2: seems to be never set in external (release) second_loader
  • 0x4: product mode. manufacturing mode (Mgmt bit 0)
  • 0x8: seems to be never set in external (release) second_loader
  • 0x40: use special media type. Never set in external (release) second_loader. Used in NSKBL when loading modules from sd0:.
  • 0x10000: seems to be never set in external (release) second_loader, allows to bypass current fw check for module loading
  • 0x20000: on resume, no boot logo
  • 0x40000: manufacturing mode (Mgmt bit 0) and GCSD initialized (for mounting sd0:) by second_loader using Ernie command 0x888
  • 0x80000: ?sd mode? - (Mgmt bit 1)

Wakeup Factor

  • 00 00 00 00 on a DEM-3000H
  • 04 00 00 00 reboot
  • 0F 00 00 00 USB Enum Wakeup
  • 14 00 00 00 boot with power hold
  • 00 FF 00 00
  • 04 FF 00 00 after normal reboot
  • 14 FF 00 00 on a PSVita in IDU mode
  • 80 xx xx xx after suspend

Deduction:

  • 1: unknown boot mode
  • 2: unknown
  • 4: reboot
  • 0xB: goes to safe mode
  • 0xF: USB enum wakeup
  • 0x10: unknown
  • 0x17: BSOD reboot
  • 0x1F: goes to safe mode
  • 0x80: suspend?
  • 0xFF00: suspend related?

Hardware Info

Data returned by Ernie.

The following list is ordered by Ernie version, that should approximately match the hardware revision order.

  • 03 10 10 00: supports FW 0.931
  • 03 20 10 00: supports FW 0.931
  • 00 40 31 00: supports FW 0.931
  • 03 24 10 00: supports FW 0.931-1.691, seems to be DEM-3000L (IRT-002) (to confirm)
  • 00 50 31 00: supports FW 0.931-1.691
  • 03 26 10 00: supports FW 0.940-3.68
  • 00 52 31 00: certainly DEM-3000H (IRT-001), supports FW 0.940-1.691
  • 00 10 41 00: supports FW 0.990-1.691
  • 00 40 41 00: supports FW 0.990-1.691
  • 00 50 41 00: supports FW 0.996-1.691
  • 00 52 41 00: supports FW 0.996-3.68
  • 00 60 41 00: PDEL-10XX (IRT-002), supports FW 1.000-3.68
  • 00 40 40 00: unknown DEX model, CEM-3000, supports FW 0.990-1.692
  • 00 41 40 00: unknown DEX model, CEM-3000, supports FW 0.990-1.692
  • 00 44 40 00: unknown DEX model, CEM-3000, supports FW 0.990-1.692
  • 00 46 40 00: unknown DEX model, CEM-3000, supports FW 0.990-1.692
  • 00 48 40 00: unknown DEX model, supports FW 1.66-1.692
  • 00 50 40 00: unknown DEX model, supports FW 1.66-3.68
  • 00 52 40 00: unknown DEX model, supports FW 1.66-3.68
  • 00 60 40 00: PCH-10XX / PTEL-10XX (IRS-002 without 3G PCIe), supports FW 1.04-3.73
  • 02 60 40 00: PCH-11XX (IRS-002 with 3G PCIe), supports FW 1.04-3.73
  • XX XX 51 00: Prototype PSTV.
  • 00 10 60 00: hybrid TOOL/DEX/CEX model (IRS-1001), supports FW 1.80-3.73
  • 00 20 60 00: unknown DEX/CEX model (IRS-1001), supports FW 1.80-3.73
  • 00 30 60 00: unknown DEX/CEX model (IRS-1001), supports FW 1.80-3.73
  • 00 32 60 00: PCH-10XX / PCH-11XX (IRS-1001), supports FW 1.80-3.73
  • 30 30 70 00: VTE-10XX (DOL-1001), supports FW 2.50-3.73
  • 38 50 80 00: PCH-20XX / PTEL-20XX (USS-1001), supports FW 2.50-3.73
  • 30 30 72 00: VTE-10XX (DOL-1002), supports FW 3.30-3.73
  • 38 22 82 00: PCH-20XX (USS-1002), supports FW 3.50-3.73
  • XX XX 90 00: Unknown prototype.

Bytes meaning

Little-endian as usual.

First byte

This byte indicates the presence of some components:

  • 00 -> FAT WIFI
  • 02 -> 3G. This is what SceBbmc checks to know if 3G is supported.
  • 03 -> probably SD card reader
  • 30 -> PSTV (USB, ethernet)
  • 38 -> SLIM (micro USB)

Second byte

This byte indicates the motherboard minor version. It is relative to the motherboard main version which is indicated by third byte.

Third byte

This byte indicates the motherboard main version:

  • 10 -> unknown prototype motherboard, has Syscon, maybe IRS-001, seems to be IRT-002 (to confirm)
  • 31 -> IRT-001
  • 40 -> IRS-002
  • 41 -> IRT-002
  • 51 -> unknown prototype, maybe IRT-003
  • 60 -> IRS-1001
  • 70 -> DOL-1001
  • 72 -> DOL-1002
  • 80 -> USS-1001
  • 82 -> USS-1002
  • 90 -> unknown prototype, maybe PSP3

Fourth byte

This byte is reserved in case 3 bytes becomes not enough to handle all Hardware Info:

  • 00 -> default, unused

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

Hardware flags

Bit Description
1 IC Conexant: 1 - yes, 2 - no
5 unk
6 unk
7 unk
14 unk
  • all zeroes on most cases
  • seen values: 47 02, 07 00 on a Slim PSVita

Types

typedef struct SceDIPSW {
  uint32_t cp_timestamp_1;
  uint16_t cp_version;
  uint16_t cp_build_id;
  uint32_t cp_timestamp_2;
  uint32_t aslr_seed;
  uint32_t sce_sdk_flags;
  uint32_t shell_flags;
  uint32_t debug_control_flags;
  uint32_t system_control_flags;
} SceDIPSW;

typedef struct SceKblParam {
  uint16_t version;
  uint16_t size;
  uint32_t current_fw_version;
  uint32_t min_fw_version;
  uint32_t unk_C;
  uint32_t unk_10;
  uint8_t unk_14[0xC];
  uint8_t qa_flags[0x10];
  uint8_t boot_flags[0x10];
  SceDIPSW dipsw;
  SceKernelPARange dram;
  uint32_t unk_68;
  uint32_t boot_type_indicator_1;
  SceOpenPsId openpsid;
  SceKernelPARange secure_kernel_enp;
  SceKernelPARange context_auth_sm_self;
  SceKernelPARange kprx_auth_sm_self;
  SceKernelPARange prog_rvk_srvk;
  ScePsCode pscode;
  uint32_t __stack_chk_guard;
  uint8_t unk_AC[4];
  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 coredump_session_key[0x20];
  uint8_t unused[0xE0];
} __attribute__((packed)) SceKblParam;
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