The Switch makes use of a customized NVIDIA driver.

nvdrv:a

Main NVIDIA driver service.

Cmd Name
0 #Open
1 #Ioctl
2 #Close
3 #Initialize
4 QueryEvent
5 MapSharedMem
6 ?
7 ?
8 BindDisplayService
9 ?

Open

Word Value
0 0x00100004
1 0x00000008
2-4 Type 5 descriptor: Device path
0-1 "SFCI"
2-3 Cmd id (0)

Ioctl

Word Value
0 0x11100004
1 0x00000C0B
? Type 0x21 descriptor: Input buffer
? Type 0x22 descriptor: Output buffer
0-1 "SFCI"
2-3 Cmd id (1)
4 Device fd
5 Ioctl Cmd

Close

Word Value
0 0x00000004
1 0x00000009
0-1 "SFCI"
2-3 Cmd id (2)
4 Device fd

Initialize

Word Value
0 0x00000004
1 0x80000009
? Handle descriptor: Current process
? Handle descriptor: Shared memory mirror
0-1 "SFCI"
2-3 Cmd id (3)
4 Shared memory size

Webkit applet creates the shared memory with perm = 0 and size 0x300000.

Ioctls

The ioctl number is generated with the following primitive (see Linux kernel):

#define _IOC(inout, group, num, len) \
   (inout | ((len & IOCPARM_MASK) << 16) | ((group) << 8) | (num))

The following table contains known ioctls.

/dev/nvhost-ctrl

Value Direction Size Description Notes
0xC0080014 Inout 8 NVHOST_IOCTL_CTRL_SYNCPT_READ
0x40040015 In 4 NVHOST_IOCTL_CTRL_SYNCPT_INCR
0xC00C0016 Inout 12 NVHOST_IOCTL_CTRL_SYNCPT_WAIT
0x40080017 In 8 NVHOST_IOCTL_CTRL_MODULE_MUTEX
0xC0180018 Inout 24 NVHOST32_IOCTL_CTRL_MODULE_REGRDWR
0xC0100019 Inout 16 NVHOST_IOCTL_CTRL_SYNCPT_WAITEX
0xC008001A Inout 8 NVHOST_IOCTL_CTRL_SYNCPT_READ_MAX
0xC004001C Inout 4
0xC010001D Inout 16 NvRmSyncWaitEvent (wait on event?)
0xC010001E Inout 16 NvRmSyncWaitEvent (wait on event?)
0xC004001F Inout 4 NvRmSyncWaitEvent (signal event?)
0xC0040020 Inout 4 NvRmSyncWaitEvent (signal event?)
0x40080021 In 8 cancel_wait_event Cancels all events

/dev/nvmap

Value Direction Size Description Notes
0xC0080101 Inout 8 NVMAP_IOC_CREATE
0x00000102 - 0 NVMAP_IOC_CLAIM Returns NotSupported
0xC0080103 Inout 8 NVMAP_IOC_FROM_ID
0xC0200104 Inout 32 NVMAP_IOC_ALLOC
0xC0180105 Inout 24 NVMAP_IOC_FREE
0xC0280106 Inout 40 NVMAP_IOC_MMAP Returns NotSupported
0xC0280107 Inout 40 NVMAP_IOC_WRITE Returns NotSupported
0xC0280108 Inout 40 NVMAP_IOC_READ Returns NotSupported
0xC00C0109 Inout 12 NVMAP_IOC_PARAM
0xC010010A Inout 16 NVMAP_IOC_PIN_MULT Returns NotSupported
0xC010010B Inout 16 NVMAP_IOC_UNPIN_MULT Returns NotSupported
0xC008010C Inout 8 NVMAP_IOC_CACHE Returns NotSupported
0xC004010D Inout 4 Returns NotSupported
0xC008010E Inout 8 NVMAP_IOC_GET_ID
0xC004010F Inout 4 Returns NotSupported
0x40040110 In 4 Returns NotSupported
0x00000111 - 0 Returns NotSupported

Channels

Channels are a concept for NVIDIA hardware blocks that share a common interface.

Path Name
/dev/nvhost-tsec
/dev/nvhost-gpu
/dev/nvhost-vic
/dev/nvhost-nvdec
/dev/nvhost-nvjpg

Channel Ioctls

Value Size Description Notes
0xC0??0001 Variable NVHOST_IOCTL_CHANNEL_SUBMIT
0xC0080002 8 NVHOST_IOCTL_CHANNEL_GET_SYNCPOINT
0xC0080003 8 NVHOST_IOCTL_CHANNEL_GET_WAITBASE
0xC0080004 8 NVHOST_IOCTL_CHANNEL_SET_TIMEOUT_EX
0x40040007 4
0xC0??0009 Variable NVHOST_IOCTL_CHANNEL_MAP_BUFFER
0xC0??000A Variable NVHOST_IOCTL_CHANNEL_UNMAP_BUFFER
0x00000013 0
0x40044801 4 NVGPU_IOCTL_CHANNEL_SET_NVMAP_FD
0x40044803 4 NVGPU_IOCTL_CHANNEL_SET_PRIORITY
0x40084805 8 NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO
0xC0044807 4 NVGPU_IOCTL_CHANNEL_CYCLE_STATS
0xC0184808 24 NVGPU_IOCTL_CHANNEL_SUBMIT_GPFIFO
0xC0104809 16 NVGPU_IOCTL_CHANNEL_ALLOC_OBJ_CTX
0x4008480A 8 NVGPU_IOCTL_CHANNEL_FREE_OBJ_CTX
0xC010480B 16 NVGPU_IOCTL_CHANNEL_ZCULL_BIND
0xC018480C 24 NVGPU_IOCTL_CHANNEL_SET_ERROR_NOTIFIER
0x4004480D 4 NVGPU_IOCTL_CHANNEL_OPEN
0x0000480E 0 NVGPU_IOCTL_CHANNEL_ENABLE
0x0000480F 0 NVGPU_IOCTL_CHANNEL_DISABLE
0x00004810 0 NVGPU_IOCTL_CHANNEL_PREEMPT
0x00004811 0 NVGPU_IOCTL_CHANNEL_FORCE_RESET
0x40084812 8 NVGPU_IOCTL_CHANNEL_EVENTS_CTRL
0xC0104813 16 NVGPU_IOCTL_CHANNEL_CYCLE_STATS_SNAPSHOT
0x80804816 128
0xC0104817 16
0x40204818 32 NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO_EX
0xC0484819 72
0xC020481A 32 NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO_EX2
0x40084714 8 set_user_address Group ID is 'H' for Horizon
0x80084715 8 get_user_address Group ID is 'H' for Horizon

Remaining Ioctls

Device Value Description Notes
/dev/nvhost-as-gpu 0x40044101 NVGPU_AS_IOCTL_BIND_CHANNEL
/dev/nvhost-as-gpu 0xC0184102 NVGPU_AS_IOCTL_ALLOC_SPACE
/dev/nvhost-as-gpu 0xC0104103 NVGPU_AS_IOCTL_FREE_SPACE
/dev/nvhost-as-gpu 0xC0184104 NVGPU_AS_IOCTL_MAP_BUFFER
/dev/nvhost-as-gpu 0xC0084105 NVGPU_AS_IOCTL_UNMAP_BUFFER
/dev/nvhost-as-gpu 0xC0284106 NVGPU_AS_IOCTL_MAP_BUFFER_EX
/dev/nvhost-as-gpu 0x40104107 init_as_gpu Initializes the as-gpu node
/dev/nvhost-as-gpu 0xC0404108 NVGPU_AS_IOCTL_GET_VA_REGIONS?
/dev/nvhost-as-gpu 0x40284109 init_as_gpu_ex Initializes the as-gpu node (with more params)
/dev/nvhost-as-gpu 0xC0144114
/dev/nvhost-dbg-gpu 0x40084401 NVGPU_DBG_GPU_IOCTL_BIND_CHANNEL
/dev/nvhost-dbg-gpu 0xC0??4402 NVGPU_DBG_GPU_IOCTL_REG_OPS ?? == size is unknown
/dev/nvhost-dbg-gpu 0x40084403 NVGPU_DBG_GPU_IOCTL_EVENTS_CTRL
/dev/nvhost-dbg-gpu 0x40044404 NVGPU_DBG_GPU_IOCTL_POWERGATE
/dev/nvhost-dbg-gpu 0x40044405 NVGPU_DBG_GPU_IOCTL_SMPC_CTXSW_MODE
/dev/nvhost-dbg-gpu 0xC0184407 NVGPU_DBG_GPU_IOCTL_PERFBUF_MAP
/dev/nvhost-dbg-gpu 0x40084408 NVGPU_DBG_GPU_IOCTL_PERFBUF_UNMAP
/dev/nvhost-dbg-gpu 0x40084409 NVGPU_DBG_GPU_IOCTL_PC_SAMPLING
/dev/nvhost-ctrl-gpu 0x80044701 NVGPU_GPU_IOCTL_ZCULL_GET_CTX_SIZE
/dev/nvhost-ctrl-gpu 0x80284702 NVGPU_GPU_IOCTL_ZCULL_GET_INFO
/dev/nvhost-ctrl-gpu 0x402C4703 NVGPU_GPU_IOCTL_ZBC_SET_TABLE
/dev/nvhost-ctrl-gpu 0xC0344704 NVGPU_GPU_IOCTL_ZBC_QUERY_TABLE
/dev/nvhost-ctrl-gpu 0xC0B04705 NVGPU_GPU_IOCTL_GET_CHARACTERISTICS
/dev/nvhost-ctrl-gpu 0xC0184706 NVGPU_GPU_IOCTL_GET_TPC_MASKS
/dev/nvhost-ctrl-gpu 0x40084707 NVGPU_GPU_IOCTL_OPEN_CHANNEL
/dev/nvhost-ctrl-gpu 0x4008470E
/dev/nvhost-ctrl-gpu 0x4010470F
/dev/nvhost-ctrl-gpu 0xC0084710
/dev/nvhost-ctrl-gpu 0x80084711
/dev/nvhost-ctrl-gpu 0x80084712
/dev/nvhost-ctrl-gpu 0xC0044713
/dev/nvhost-ctrl-gpu 0x80084714
/dev/nvhost-ctrl-gpu 0x80044715
/dev/nvhost-ctrl-gpu 0x8018471A
/dev/nvhost-ctrl-gpu 0xC008471B
/dev/nvhost-ctrl-gpu 0xC010471C

nvmemp

NVIDIA memory profiler (this service is not available on retail units).

mm:u

NVIDIA multimedia (NvMM) platform service.

Cmd Name
0 ?
1 ?
2 ?
3 ?
4 module_init_clk
5 module_deinit_clk
6 module_set_clk_rate
7 module_get_clk_rate

Errors

Most nvidia driver commands return an error code apart from the normal return code.

Cmd Name
0 Success
1 NotImplemented
2 NotSupported
3 NotInitialized
4 BadParameter
5 Timeout
6 InsufficientMemory
7 ReadOnlyAttribute
8 InvalidState
9 InvalidAddress
0xA InvalidSize
0xB BadValue
0xD AlreadyAllocated
0xE Busy
0xF ResourceError
0x10 CountMismatch
0x1000 Shared memory too small