System calls

Id Name In Out
0x1 #svcSetHeapSize W1=size W0=result, X1=outaddr
0x2 #svcSetMemoryPermission X0=addr, X1=size, W2=prot W0=result
0x3 #svcSetMemoryAttribute X0=addr, X1=size, W2=state0, W3=state1 W0=result
0x4 #svcMapMemory X0=dstaddr, X1=srcaddr, X2=size W0=result
0x5 svcUnmapMemory X0=dstaddr, X1=srcaddr, X2=size W0=result
0x6 svcQueryMemory X0=meminfo_ptr, X2=addr W0=result, W1=pageinfo
0x7 svcExitProcess None
0x8 #svcCreateThread X1=entry, X2=arg, X3=stacktop, W4=prio, W5=processor_id W0=result, W1=handle
0x9 svcStartThread W0=thread_handle
0xA svcExitThread None
0xB #svcSleepThread X0=nano
0xC svcGetThreadPriority W1=thread_handle W0=result, W1=prio
0xD svcSetThreadPriority W0=thread_handle, W1=prio W0=result
0xE svcGetThreadCoreMask W2=thread_handle W0=result, W1=out, X2=out
0xF svcSetThreadCoreMask W0=thread_handle, W1=in, X2=in2 W0=result
0x10 svcGetCurrentProcessorNumber None W0/X0=cpuid
0x11 svcSignalEvent W0=handle ?
0x12 svcClearEvent W0=handle ?
0x13 svcMapSharedMemory W0=memblk_handle, X1=addr, X2=size, W3=perm W0=result
0x14 svcUnmapSharedMemory W0=memblk_handle, X1=addr, X2=size W0=result
0x15 #svcCreateTransferMemory X1=addr, X2=size, W3=perm W0=result, W1=handle
0x16 svcCloseHandle W0=handle W0=result
0x17 svcResetSignal W0=handle W0=result
0x18 #svcWaitSynchronization X1=handles_ptr, W2=num_handles. X3=timeout W0=result, W1=handle_idx
0x19 svcCancelSynchronization W0=handle W0=result
0x1A svcArbitrateLock W0=cur_thread_handle, X1=ptr, W2=req_thread_handle
0x1B svcArbitrateUnlock X0=ptr
0x1C svcWaitProcessWideKeyAtomic X0=ptr0, X1=ptr, W2=thread_handle, X3=timeout W0=result
0x1D svcSignalProcessWideKey X0=ptr, W1=value W0=result
0x1E svcGetSystemTick
0x1F svcConnectToPort X1=port_name_str W0=result, W1=handle
0x20 svcSendSyncRequestLight
0x21 svcSendSyncRequest X0=handle W0=result
0x22 #svcSendSyncRequestWithUserBuffer X0=cmdbufptr, X1=size, X2=handle W0=result
0x23 svcSendAsyncRequestWithUserBuffer
0x24 svcGetProcessId
0x25 svcGetThreadId W0=thread_handle W0=result, X1=out
0x26 svcBreak X0,X1,X2=info ?
0x27 svcOutputDebugString X0=str, X1=size
0x28 svcReturnFromException X0=result
0x29 #svcGetInfo X1=info_id, X2=handle, X3=info_sub_id W0=result, X1=out
0x2A svcFlushEntireDataCache
0x2B svcFlushDataCache
0x2C svcFlushEntireInsnCache?
0x2D svcFlushInsnCache?
.... ? ? ?
0x2F svcGetLastThreadInfo
0x30 svcGetResourceLimitLimitValue
0x31 svcGetResourceLimitCurrentValue
0x32 svcSetThreadActivity
0x33 svcGetThreadContext3
.... ? ? ?
0x3C svcDumpInfo
.... ? ? ?
0x40 svcCreateSession W2=?, X3=? W0=result, W1=client_handle, W2=server_handle
0x41 svcAcceptSession W1=port_handle W0=result, W1=session_handle
0x42 svcReplyAndReceiveLight
0x43 svcReplyAndReceive X1=ptr_handles, W2=num_handles, X3=?, X4=timeout W0=result, W1=handle_idx
0x44 svcReplyAndReceiveWithUserBuffer X1=buf, X2=sz, X3=ptr_handles, W4=num_handles, X5=?, X6=timeout W0=result, W1=handle_idx
0x45 svcCreateEvent None W0=result, W1=client_handle ?, W2=server_handle ?
.... ? ? ?
0x4D svcSleepSystem
0x4E svcReadWriteRegister
0x4F svcSetProcessActivity
0x50 svcCreateSharedMemory W1=size?, W2=perm0, W3=perm1 W0=result, W1=handle
0x51 #svcMapTransferMemory X0=mirror_handle, X1=addr, X2=size, W3=perm W0=result
0x52 #svcUnmapTransferMemory W0=mirror_handle, X1=addr, X2=size W0=result
0x53 svcCreateInterruptEvent
0x54 svcQueryPhysicalAddress
0x55 svcQueryToMapping
0x56 svcCreateDeviceAddressSpace
0x57 svcAttachDeviceAddressSpace
0x58 svcDetachDeviceAddressSpace
0x59 svcMapDeviceAddressSpaceByForce
0x5A svcMapDeviceAddressSpaceAligned
0x5B svcMapDeviceAddressSpace
0x5C svcUnmapDeviceAddressSpace
0x5D svcInvalidateProcessDataCache
0x5E svcStoreProcessDataCache
0x5F svcFlushProcessDataCache
0x60 svcDebugActiveProcess
0x61 svcBreakDebugProcess
0x62 svcTerminateDebugProcess
0x63 svcGetDebugEvent
0x64 svcContinueDebugEvent
0x65 svcGetProcessList
0x66 svcGetThreadList
0x67 svcGetDebugThreadContext
0x68 svcSetDebugThreadContext
0x69 svcQueryDebugProcessMemory
0x6A svcReadDebugProcessMemory
0x6B svcWriteDebugProcessMemory
0x6C svcSetHardwareBreakPoint
0x6D svcGetDebugThreadParam
.... ? ? ?
0x70 svcCreatePort
0x71 svcManageNamedPort
0x72 svcConnectToPort
0x73 svcSetProcessMemoryPermission
0x74 svcMapProcessMemory X0=srcaddr, W1=process_handle, X2=dstaddr, X3=size W0=result
0x75 svcUnmapProcessMemory W0=process_handle, X1=dstaddr, X2=srcaddr, X3=size W0=result
0x76 svcQueryProcessMemory
0x77 svcMapProcessCodeMemory W0=process_handle, X21dstaddr, X2=srcaddr, X3=size W0=result
0x78 svcUnmapProcessCodeMemory W0=process_handle, X1=dstaddr, X2=srcaddr, X3=size W0=result
0x79 svcCreateProcess
0x7A svcStartProcess
0x7B svcTerminateProcess
0x7C svcGetProcessInfo
0x7D svcCreateResourceLimit
0x7E svcSetResourceLimitLimitValue
0x7F svcCallSecureMonitor

svcSetHeapSize

Size must be a multiple of 0x2000000. The heap base-address is written to out.

svcSetMemoryPermission

Bit2 of permission (exec) is not allowed.

Setting write-only is not allowed either (bit1).

svcSetMemoryAttribute

State0 State1 Action
0 0 Clear bit35 in #MemoryAttribute.
8 0 Clear bit35 in #MemoryAttribute.
8 8 Set bit35 in #MemoryAttribute.

This might used for switching between cached and non-cached mappings.

svcMapMemory

Memory is only allowed to be mapped into a special region.

Code can get the range of this region from #svcGetInfo.

The source region gets reprotected to ---, and sets bit32 is set in #MemoryAttribute.

svcCreateThread

Processor_id must be 0,1,2,3 or -2.

svcSleepThread

Setting nano=0 means "yield thread".

svcCreateTransferMemory

This one reprotects the src block with perms you give it. It also sets bit32 into #MemoryAttribute.

Executable bit perm not allowed.

Closing all handles automatically causes the bit32 in #MemoryAttribute to clear, and the permission to reset.

svcWaitSynchronization

Works with num_handles <= 0x40, error on num_handles == 0.

Does not accept 0xFFFF8001 or 0xFFFF8000 as handles.

svcSendSyncRequestWithUserBuffer

Size must be 0x1000-aligned.

svcBreak

When used on retail where inx0 bit31 is clear, the system will throw a fatal-error. Otherwise when bit31 is set, it will return 0.

svcGetInfo

Handle type Id0 Id1 Description
Process 0 0 Core available mask. Always 0xF meaning all 4 cores available.
Process 1 0 Always 0xfffffffff0000000.
Process 2 0 Randomized unknown base-address.
Process 3 0 Always 0x1000000000.
Process 4 0 Heap base. Randomized.
Process 5 0 Heap region size. Always 0x180000000.
Process 6 0 Total memory usage?
Process 7 0 Process heap size.
Zero 8 0 Always 0. Used during exception handling.
Zero 9 0 This creates and returns an unknown handle.
Zero 10 -1, {current coreid} Unknown. Output data changes each time this SVC is used. Global and core-specific tick-count?
Zero 11 0-3 Returns random from TRNG. Used to seed usermode PRNGs. Unknown what exactly causes this output to change, however it does change when exiting+launching a process.
Process 12 0 Address space start. Always 0x8000000.
Process 13 0 Address space size. Always 0x7ff8000000.
Process 14 0 Map region base. Randomized.
Process 15 0 Map region size.
Process 18 0 Title-id, introduced with 3.0.0

svcMapTransferMemory

The newly mapped pages will have #MemoryAttribute type 0xE.

You must pass same size and permissions as given in svcCreateMemoryMirror, otherwise error.

svcUnmapTransferMemory

Size must match size given in map syscall, otherwise there's an invalid-size error.

MemoryAttribute

Lower 8 bits Type Meaning
0x3 Code static .text and .rodata
0x4 Code .data
0x5 Heap
0x6 Shared memory block
0x8 Module code static .text and .rodata
0x9 Module code .data
0xB Mapped memory
0xC Thread local storage
0xE Transfer memory
0x10 Reserved

Bit32: is_mirrored Bit34: is_nv_locked Bit35: is_uncached?

Exception Handling

There appears to be userland code for handling exceptions, however this doesn't seem to be executed on retail.

On usermode exception, it jumps to main code binary entrypoint (main_binary_address+0) with X0=exception_info_ptr and X1=exception_info2_ptr. On boot, X0 is set to 0 triggering normal crt0 setup.