NSKBL

Non-Secure Kernel Boot Loader (NSKBL) is a Non-Secure world program that performs eMMC setup, base kernel modules loading, etc. during PSVita boot.

Module
The NSKBL contains an embedded and likely stripped version of SceSysmem, SceKernelModulemgr, SceSblSmschedProxy, SceExcpmgr, SceKernelIntrMgr, SceSblAuthMgr, SceProcessmgr (maybe), SceSdif, SceIofilemgr (Simple version?), and some other core drivers.

How to debug NSKBL
NSKBL supports sd0: for debugging. pKblParam->boot_type_indicator_1 = 0x40000 is required.

sceIoOpen(?) error code 0x803FF007
This error can occur if the file is fragmented.

SceKblForKernel_29A8524D
Related to SDbgSdio (System Debug Sdio) and requires DIPSW 193.

sceKblPutcharForKernel
In 3.60 this function is at 0x510172BD

sceKernelPrintfForKernel
In 3.60 this function is at 0x510137A9

sceKernelPrintfLevelForKernel
In 3.60 this function is at 0x51013841.

sceKernelGetDebugLevelForKernel
Temp name was sceKblGetMinimumLogLevel.

In 3.60 this function is at 0x51013921.

sceKernelGetDebugPutcharForKernel
In 3.60 this function is at 0x51013765.

sceKernelSysrootProcessmgrStart2ForKernel
In 3.60 this function is at 0x510123DD.

sceKernelSysrootThreadMgrStartAfterProcessForKernel
In 3.60 this function is at 0x510123A1.

sceKernelSysrootIofilemgrStartForKernel
In 3.60 this function is at 0x5101297D.

sceKernelSysrootCorelockUnlockForKernel
In 3.60 this function is at 0x510124FD.

sceKernelSysrootCorelockLockForKernel
In 3.60 this function is at 0x510124E5.

sceKblCpuDisableIrqInterruptsForKernel
In 3.60 this function is at 0x51003554.

Temp name was sceKblCpuSwitchInterruptsForKernel.

sceSblAimgrIsCEXForKernel
In 3.60 this function is at 0x510171B5.

sceSblAimgrIsDiagForKernel
In 3.60 this function is at 0x51017175.

sceSblAimgrIsDEXForKernel
In 3.60 this function is at 0x51017159.

sceSblAimgrIsToolForKernel
In 3.60 this function is at 0x51017139.

sceSblAimgrIsTestForKernel
In 3.60 this function is at 0x5101711D.

sceSblAimgrIsVITAForKernel
In 3.60 this function is at 0x51017299.

sceSblAimgrIsDolceForKernel
In 3.60 this function is at 0x510172A1.

sceSblAimgrIsGenuineDolceForKernel
In 3.60 this function is at 0x510171E5.

sceKblLoadModuleForKernel
In 3.60 this function is at 0x51001551.

sceKblStartModuleForKernel
In 3.60 this function is at 0x51001571

sceKblAuthMgrCloseForKernel
In 3.60 this function is at 0x51001345.

sceKblSetNonSyncModuleStartForKernel
In 3.60 this function is at 0x51001561.

sceKernelCpuIdForKernel
In 3.60 this function is at 0x510147C9.

sceKernelCheckDipswForKernel
In 3.60 this function is at 0x51015851.

sceSblQafManagerIsAllowKernelDebugForKernel
In 3.60 this function is at 0x51016FD1

sceKblGetHardwareFlagsForKernel
get some device flags function

In 3.60 this function is at 0x510128AD

sceKblInitDeviceForKernel
some device init function

In 3.60 this function is at 0x5100124D.

sceKblFreeFileSystemCtxForKernel
In 3.60 this function is at 0x51001321.