SVC

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	svcConnectToNamedPort	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	[ 3.0.0+ ] svcMapPhysicalMemory
0x2D	[ 3.0.0+ ] svcUnmapPhysicalMemory
....	?	?	?
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	X1=reg_addr, W2=rw_mask, W3=in_val	W0=result, W1=out_val
0x4F	svcSetProcessActivity
0x50	#svcCreateSharedMemory	W1=size?, W2=myperm, W3=otherperm	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	X1=irq_id	W0=result, W1=handle
0x54	#svcQueryPhysicalAddress
0x55	#svcQueryIoMapping	X0=physaddr, X1=size	X0=virtaddr
0x56	svcCreateDeviceAddressSpace	X1=dev_addr, X2=dev_size	W0=result, W1=handle
0x57	#svcAttachDeviceAddressSpace	W0=device, X1=handle	W0=result
0x58	#svcDetachDeviceAddressSpace	W0=device, X1=handle	W0=result
0x59	svcMapDeviceAddressSpaceByForce	W0=handle, W1=proc_handle, X2=dev_addr, X3=dev_size, X4=map_addr, W5=perm	W0=result
0x5A	svcMapDeviceAddressSpaceAligned
0x5B	svcMapDeviceAddressSpace
0x5C	svcUnmapDeviceAddressSpace	W0=handle, W1=proc_handle, X2=map_addr, X3=map_size, W4=perm	W0=result
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	X1=procinfo_ptr, X2=caps_ptr, W3=cap_num	W0=result, W1=process_handle
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.

It allows both extending and shrinking the heap.

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".

svcMapSharedMemory

Maps the block supplied by the handle. The required permissions are different for the process that created the handle and all other processes.

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
?	0xF0000002	0	Unknown. Uses the input handle. Returns a tick-count?

svcReadWriteRegister

Read/write Tegra hardware registers, input address is physical-address.

rw_mask is 0 for reading and -1 for writing.

Registers

Address	Register Name	Description
0x700192E8	MC_LATENCY_ALLOWANCE_DC_0_0	Latency allowance settings for DC clients
0x700192EC	MC_LATENCY_ALLOWANCE_DC_1_0	Latency allowance settings for DC clients
0x700192F0	MC_LATENCY_ALLOWANCE_DC_2_0	Latency allowance settings for DC clients
0x700192F4	MC_LATENCY_ALLOWANCE_DCB_0_0	Latency allowance settings for DCB clients
0x700192F8	MC_LATENCY_ALLOWANCE_DCB_1_0	Latency allowance settings for DCB clients
0x7001941C	MC_DIS_PTSA_RATE_0	DDA rate for dis PTSA
0x70019420	MC_DIS_PTSA_MIN_0	DDA minimum value for direct client dis PTSA.
0x70019424	MC_DIS_PTSA_MAX_0	DDA maximum value for direct client dis PTSA.
0x70019428	MC_DISB_PTSA_RATE_0	DDA rate for disb PTSA
0x7001942C	MC_DISB_PTSA_MIN_0	DDA minimum value for direct client disb PTSA
0x70019430	MC_DISB_PTSA_MAX_0	DDA maximum value for direct client disb PTSA
0x7001944C	MC_MLL_MPCORER_PTSA_RATE_0	DDA rate for mll_mpcorer PTSA
0x7001947C	MC_RING1_PTSA_RATE_0	DDA rate for ring1 PTSA
0x70019480	MC_RING1_PTSA_MIN_0	DDA minimum value for direct client ring1 PTSA
0x70019484	MC_RING1_PTSA_MAX_0	DDA maximum value for direct client ring1 PTSA
0x7001950C	MC_FTOP_PTSA_RATE_0	DDA rate for ftop PTSA
0x70019670	MC_SEC_CARVEOUT_BOM_0	Baseaddress for the SEC carveout address space.
0x70019674	MC_SEC_CARVEOUT_SIZE_MB_0	Size in MB for the SEC carveout region
0x70019690	MC_SCALED_LATENCY_ALLOWANCE_DISPLAY0A_0	Scaled Latency Allowance settings for DISPLAY0A
0x70019694	MC_SCALED_LATENCY_ALLOWANCE_DISPLAY0AB_0	Scaled Latency Allowance settings for DISPLAY0AB
0x70019698	MC_SCALED_LATENCY_ALLOWANCE_DISPLAY0B_0	Scaled Latency Allowance settings for DISPLAY0B
0x7001969C	MC_SCALED_LATENCY_ALLOWANCE_DISPLAY0BB_0	Scaled Latency Allowance settings for DISPLAY0BB
0x700196A0	MC_SCALED_LATENCY_ALLOWANCE_DISPLAY0C_0	Scaled Latency Allowance settings for DISPLAY0C
0x700196A4	MC_SCALED_LATENCY_ALLOWANCE_DISPLAY0CB_0	Scaled Latency Allowance settings for DISPLAY0CB
0x70019C5C

svcCreateSharedMemory

Other perm can be used to enforce permission 1, 3, or 0x10000000 if don't care.

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.

svcQueryPhysicalAddress

The inverse operation of #svcQueryIoMapping.

svcCreateProcess

Takes a #CreateProcessInfo as input.

svcAttachDeviceAddressSpace / svcDetachDeviceAddressSpace

These take a device id and a device address space handle.

Device	Name	Description
0x0A	APBDMA	Tegra's APB DMA controller.

Structures

CreateProcessInfo

Offset	Length	Description
0	8
8	2
0xA	2
0x18	8	Code base
0x20	4	Number of code pages
0x24	4	MemoryManagement flags. Bit0: is_64bit (maybe?), bit3-1: MMU table size? (0=32-bit, 1=64-bit 0x800000000, 2=64-bit 0x400000000), bit5, bit6
0x28	4	ResourceLimit handle
0x2C	4

MemoryAttribute

Bits	Description
7-0	Type
8	Can be used with #svcSetMemoryPermission
14	Can be used with #svcSetProcessMemoryPermission
15	Can be used with #svcMapMemory
17	Can be used with #svcCreateTransferMemory
21	Can be used with #svcSendSyncRequestWithUserBuffer
24	Can be used with #svcSetMemoryAttribute

Value	Type	Meaning
0x0	Unmapped
0x2001	IO	Mapped by kernel capability parsing in #svcCreateProcess.
0x42002	IO	Mapped by kernel capability parsing in #svcCreateProcess.
0xDC7E03	Code static	Mapped during #svcCreateProcess.
0x4	Code	.data
0x17EBD05	Heap	Mapped using #svcSetHeapSize.
0x402006	Shared memory block	Mapped using #svcMapSharedMemory.
0x482907	Weird mapped memory	Mapped using #svcMapMemory.
0x8	Module code static
0x9	Module code	.data
0x5C3C0B	Mapped memory	Mapped using #svcMapMemory.
0xC	Thread local storage	Mapped during #svcCreateThread.
0x15C3C0D	Weird transfer memory	Mapped using #svcMapTransferMemory.
0x5C380E	Transfer memory	Mapped using #svcMapTransferMemory.
0x40380F	Process memory	Mapped using #svcMapProcessMemory.
0x10	Reserved

Bit32: is_mirrored Bit34: is_device_mapped 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.