NV services

The Switch makes use of a customized NVIDIA driver.

nvdrv, nvdrv:a, nvdrv:s, nvdrv:t

Main NVIDIA driver service.

Each service is used by:

• "nvdrv": regular applications
• "nvdrv:a": applets
• "nvdrv:s": sysmodules
• "nvdrv:t": Not known to be used by anything on retail.

Cmd	Name
0	#Open
1	#Ioctl
2	#Close
3	#Initialize
4	QueryEvent
5	MapSharedMem
6	GetStatus
7	ForceSetClientPID
8	SetClientPID
9	DumpGraphicsMemoryInfo
10	[3.0.0+]
11	[3.0.0+] Ioctl2
12	[3.0.0+] Ioctl3
13	[3.0.0+]

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	#NVHOST_IOCTL_CTRL_MODULE_REGRDWR
0xC0100019	Inout	16	#NVHOST_IOCTL_CTRL_SYNCPT_WAITEX
0xC008001A	Inout	8	#NVHOST_IOCTL_CTRL_SYNCPT_READ_MAX
0xC183001B	Inout	387	NVHOST_IOCTL_CTRL_GET_CONFIG
0xC004001C	Inout	4	#NVHOST_IOCTL_CTRL_EVENT_SIGNAL
0xC010001D	Inout	16	#NVHOST_IOCTL_CTRL_EVENT_WAIT
0xC010001E	Inout	16	#NVHOST_IOCTL_CTRL_EVENT_WAIT_ASYNC
0xC004001F	Inout	4	#NVHOST_IOCTL_CTRL_EVENT_REGISTER
0xC0040020	Inout	4	#NVHOST_IOCTL_CTRL_EVENT_UNREGISTER
0x40080021	In	8	#NVHOST_IOCTL_CTRL_EVENT_KILL

NVHOST_IOCTL_CTRL_SYNCPT_READ

Identical to Linux driver.

 struct {
   u32 __id;      // in
   u32 __value;   // out
 };

NVHOST_IOCTL_CTRL_SYNCPT_INCR

Identical to Linux driver.

 struct {
   u32 __id;      // in
 };

NVHOST_IOCTL_CTRL_SYNCPT_WAIT

Identical to Linux driver.

 struct {
   u32 __id;          // in
   u32 __thresh;      // in
   s32 __timeout;     // in
 };

NVHOST_IOCTL_CTRL_MODULE_MUTEX

Identical to Linux driver.

 struct {
   u32 __id;          // in
   u32 __lock;        // in (0==unlock; 1==lock)
 };

NVHOST_IOCTL_CTRL_MODULE_REGRDWR

Identical to Linux driver. Uses 32-bit version and doesn't work.

 struct {
   u32 __id;           // in
   u32 __num_offsets;  // in
   u32 __block_size;   // in
   u32 __offsets;      // in
   u32 __values;       // in
   u32 __write;        // in
 };

NVHOST_IOCTL_CTRL_SYNCPT_WAITEX

Identical to Linux driver.

 struct {
   u32 __id;          // in
   u32 __thresh;      // in
   s32 __timeout;     // in
   u32 __value;       // out
 };

NVHOST_IOCTL_CTRL_SYNCPT_READ_MAX

Identical to Linux driver.

 struct {
   u32 __id;      // in
   u32 __value;   // out
 };

NVHOST_IOCTL_CTRL_EVENT_SIGNAL

Signals an event. Exclusive to the Switch.

 struct {
   u32 __event_id;      // in (ranges from 0x01 to 0x3F)
 };

NVHOST_IOCTL_CTRL_EVENT_WAIT

Waits on an event. Exclusive to the Switch.

 struct {
   u32 __unk0;         // in
   u32 __unk1;         // in
   s32 __timeout;      // in
   u32 __event;        // inout (in=event_id; out=result)
 };

NVHOST_IOCTL_CTRL_EVENT_WAIT_ASYNC

Waits on an event (async version). Exclusive to the Switch.

 struct {
   u32 __unk0;         // in
   u32 __unk1;         // in
   s32 __timeout;      // in
   u32 __event;        // inout (in=event_id; out=result)
 };

NVHOST_IOCTL_CTRL_EVENT_REGISTER

Registers an event. Exclusive to the Switch.

 struct {
   u32 __event_id;      // in (ranges from 0x01 to 0x3F)
 };

NVHOST_IOCTL_CTRL_EVENT_UNREGISTER

Unregisters an event. Exclusive to the Switch.

 struct {
   u32 __event_id;      // in (ranges from 0x01 to 0x3F)
 };

NVHOST_IOCTL_CTRL_EVENT_KILL

Kills events. Exclusive to the Switch.

 struct {
   u64 __events;      // in (64-bit flag where each bit represents one event)
 };

/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

NVMAP_IOC_CREATE

Creates an nvmap object. Identical to Linux driver.

 struct {
   u32 __size;   // in
   u32 __handle; // out
 };

NVMAP_IOC_FROM_ID

Get handle to an existing nvmap object. Identical to Linux driver.

 struct {
   u32 __id;     // in
   u32 __handle; // out
 };

NVMAP_IOC_ALLOC

Allocate memory for the nvmap object. Nintendo extended this one with 16 bytes, and changed it from in to inout.

 struct {
   u32 __handle;   // in
   u32 __heapmask; // in
   u32 __flags;    // in (0=read-only, 1=read-write)
   u32 __align;    // in
   u8  __kind;     // in
   u8  __pad[7];
   u64 __addr;     // in
 };

NVMAP_IOC_FREE

This one is completely custom. Partly because the Linux driver passed the handle as the ioctl "arg-ptr", and HIPC can't handle that voodoo.

 struct {
   u32 __handle;   // in
   u32 __pad;
   u64 __refcount; // out
   u32 __size;     // out
   u32 __flags;    // out, 1=NOT_FREED_YET
 };

NVMAP_IOC_PARAM

Returns info about a nvmap object. Identical to Linux driver, but extended with further params.

 struct {
   u32 __handle; // in
   u32 __param;  // in, 1=SIZE, 2=ALIGNMENT, 3=BASE (returns error), 4=HEAP (always 0x40000000), 5=KIND, 6=COMPR (unused)
   u32 __result; // out
 };

NVMAP_IOC_GET_ID

Returns an id for a nvmap object. Identical to Linux driver.

 struct {
   u32 __id;     // out
   u32 __handle; // in
 };

/dev/nvdisp-ctrl

Value	Direction	Size	Description	Notes
0x80040212	Out	4	TEGRA_DC_EXT_CONTROL_GET_NUM_OUTPUTS
0xC0140213	Inout	20	TEGRA_DC_EXT_CONTROL_GET_OUTPUT_PROPERTIES
0xC1100214	Inout	272	TEGRA_DC_EXT_CONTROL_GET_OUTPUT_EDID
0xC0040216	Inout	4	TEGRA_DC_EXT_CONTROL_SET_EVENT0
0xC0040217	Inout	4	TEGRA_DC_EXT_CONTROL_SET_EVENT1
0xC0100218	Inout	16	TEGRA_DC_EXT_CONTROL_SET_EVENT2
0xC0100219	Inout	16	TEGRA_DC_EXT_CONTROL_SET_EVENT3
0xC0040220	Inout	4	TEGRA_DC_EXT_CONTROL_SET_EVENT4

/dev/nvdisp-disp0, /dev/nvdisp-disp1

Value	Direction	Size	Description	Notes
0x40040201	In	4	TEGRA_DC_EXT_GET_WINDOW
0x40040202	In	4	TEGRA_DC_EXT_PUT_WINDOW
0xC4C80203	In	1224	TEGRA_DC_EXT_FLIP
0x80380204	Out	56	TEGRA_DC_EXT_GET_MODE
0x40380205	Out	56	TEGRA_DC_EXT_SET_MODE
0x430C0206	In	780	TEGRA_DC_EXT_SET_LUT
0x40010207	In	1	TEGRA_DC_EXT_ENABLE_DISABLE_CRC
0x80040208	Out	4	TEGRA_DC_EXT_GET_CRC
0x80040209	Out	4	TEGRA_DC_EXT_GET_HEAD_STATUS
0xC038020A	Inout	56	TEGRA_DC_EXT_VALIDATE_MODE
0x4018020B	In	24	TEGRA_DC_EXT_SET_CSC
0xC004020C	Inout	4	TEGRA_DC_EXT_GET_VBLANK_SYNCPT
0x8040020D	Out	64	TEGRA_DC_EXT_GET_UNDERFLOWS
0xC99A020E	Inout	2458	TEGRA_DC_EXT_SET_CMU
0xC004020F	Inout	4	TEGRA_DC_EXT_DPMS
0x80600210	Out	96	TEGRA_DC_EXT_GET_AVI_INFOFRAME
0x40600211	In	96	TEGRA_DC_EXT_SET_AVI_INFOFRAME
0xEBFC0215	Inout	11260	TEGRA_DC_EXT_GET_MODE_DB
0xC003021A	Inout	3	TEGRA_DC_EXT_PANEL_GET_VENDOR_ID
0x803C021B	Out	60	TEGRA_DC_EXT_GET_MODE2
0x403C021C	In	60	TEGRA_DC_EXT_SET_MODE2
0xC03C021D	Inout	60	TEGRA_DC_EXT_VALIDATE_MODE2
0xEF20021E	Inout	12064	TEGRA_DC_EXT_GET_MODE_DB2
0xC004021F	Inout	4	TEGRA_DC_EXT_GET_WINMASK

/dev/nvcec-ctrl

Value	Direction	Size	Description	Notes
0x40010300	In	1
0x40010301	In	1	NVCEC_CTRL_ENABLE
0x804C0302	Out	76	NVCEC_CTRL_GET_PADDR
0x40040303	In	4	NVCEC_CTRL_SET_LADDR
0xC04C0304	Inout	76	NVCEC_CTRL_WRITE
0xC04C0305	Inout	76	NVCEC_CTRL_READ
0x804C0306	Out	76	NVCEC_CTRL_GET_CONNECTION_STATUS
0x804C0307	Out	76	NVCEC_CTRL_GET_WRITE_STATUS

/dev/nvhdcp_up-ctrl

Value	Direction	Size	Description	Notes
0xC4880401	Inout	1160
0xC4880402	Inout	1160
0x40010403	In	1

/dev/nvdcutil-disp0, /dev/nvdcutil-disp1

Value	Direction	Size	Description	Notes
0x40010501	In	1
0x40010502	In	1
0x42040503	In	1056
0x803C0504	Out	60

/dev/nvsched-ctrl

Value	Direction	Size	Description	Notes
0x00000601	-	0
0x00000602	-	0
0x40180603	In	1056
0x40180604	In	60
0x40080605	In	60
0x80080606	Out	60
0x80080607	Out	60
0x40180608	In	24
0x40100609	In	16
0x4010060A	In	16
0x4008060B	In	8
0x8001060C	Out	1
0x8010060D	Out	16
0x400C060E	In	12
0x4008060F	In	8
0x40100610	In	16
0x40100611	In	16

/dev/nvhost-as-gpu

Each fd opened to this device creates an address space. An address space is then later bound with a channel.

Once a nvgpu channel has been bound to an address space it cannot be unbound. There is no support for allowing an nvgpu channel to change from one address space to another (or from one to none).

Value	Direction	Size	Description	Notes
0x40044101	In	4	#NVGPU_AS_IOCTL_BIND_CHANNEL
0xC0184102	Inout	24	#NVGPU_AS_IOCTL_ALLOC_SPACE
0xC0104103	Inout	16	#NVGPU_AS_IOCTL_FREE_SPACE
0xC0184104	Inout	24	#NVGPU_AS_IOCTL_MAP_BUFFER
0xC0084105	Inout	8	#NVGPU_AS_IOCTL_UNMAP_BUFFER
0xC0284106	Inout	40	#NVGPU_AS_IOCTL_MAP_BUFFER_EX
0x40104107	In	16	#NVGPU_AS_IOCTL_INITIALIZE
0xC0404108	Inout	64	#NVGPU_AS_IOCTL_GET_VA_REGIONS
0x40284109	In	40	#NVGPU_AS_IOCTL_INITIALIZE_EX
0xC0144114	Inout	20	NVGPU_AS_IOCTL_REMAP

NVGPU_AS_IOCTL_BIND_CHANNEL

Identical to Linux driver.

 struct {
   u32 __fd; // in
 };

NVGPU_AS_IOCTL_ALLOC_SPACE

This one reserves pages in the device address space.

 struct {
   u32 __pages;     // in
   u32 __page_size; // in
   u32 __flags;     // in
   u32 __pad;
   union {
     u64 __offset;  // out
     u64 __align;   // in
   };
 };

NVGPU_AS_IOCTL_FREE_SPACE

 struct {
   u64 __offset;    // in
   u32 __pages;     // in
   u32 __page_size; // in
 };

NVGPU_AS_IOCTL_MAP_BUFFER

Map a memory region in the device address space. Identical to Linux driver pretty much.

On success, the mapped memory region is locked by having SVC#MemoryState bit34 set.

 struct {
   u32 __flags;        // in, 4 works
   u32 __reserved;
   u32 __nvmap_handle; // in
   u32 __page_size;    // inout, 0 means don't care
   union {
     u64 __offset;     // out
     u64 __align;      // in
   };
 };

NVGPU_AS_IOCTL_MAP_BUFFER_EX

Map a memory region in the device address space. Identical to Linux driver pretty much.

On success, the mapped memory region is locked by having SVC#MemoryState bit34 set.

 struct {
   u32 __flags;          // in, 4 works
   u32 __kind;           // in, -1 is default
   u32 __nvmap_handle;   // in
   u32 __page_size;      // inout, 0 means don't care
   u64 __buffer_offset;  // in
   u64 __mapping_size;   // in
   u64 __offset;         // out
 };

NVGPU_AS_IOCTL_UNMAP_BUFFER

Doesn't do shit.

NVGPU_AS_IOCTL_INITIALIZE

Nintendo's custom implementation of NVGPU_GPU_IOCTL_ALLOC_AS (unavailable).

 struct {
   u32 __big_page_size;   // in (depends on GPU's available_big_page_sizes; 0=default)
   s32 __as_fd;           // in (ignored; passes 0)
   u32 __flags;           // in (ignored; passes 0)
   u32 __reserved;        // in (ignored; passes 0)
 };

NVGPU_AS_IOCTL_GET_VA_REGIONS

Nintendo modified to get rid of pointer in struct.

 struct va_region {
   u64 __offset;
   u32 __page_size;
   u32 __reserved;
   u64 __pages;
 };
 
 struct {
   u64              __not_used;   // (contained output user ptr on linux, ignored)
   u32              __bufsize;    // inout, forced to 2*sizeof(struct va_region)
   u32              __reserved;
   struct va_region __regions[2]; // out
 };

NVGPU_AS_IOCTL_INITIALIZE_EX

Nintendo's custom implementation of NVGPU_GPU_IOCTL_ALLOC_AS (unavailable) with extra params.

 struct {
   u32 __big_page_size;   // in (depends on GPU's available_big_page_sizes; 0=default)
   s32 __as_fd;           // in (ignored; passes 0)
   u32 __flags;           // in (ignored; passes 0)
   u32 __reserved;        // in (ignored; passes 0)
   u64 __unk0;            // in
   u64 __unk1;            // in
   u64 __unk2;            // in
 };

/dev/nvhost-dbg-gpu

Not accessible, but there is code to invoke it.

Value	Direction	Size	Description	Notes
0x40084401	In	8	NVGPU_DBG_GPU_IOCTL_BIND_CHANNEL
0xC0??4402	Inout	Variable	NVGPU_DBG_GPU_IOCTL_REG_OPS
0x40084403	In	8	NVGPU_DBG_GPU_IOCTL_EVENTS_CTRL
0x40044404	In	4	NVGPU_DBG_GPU_IOCTL_POWERGATE
0x40044405	In	4	NVGPU_DBG_GPU_IOCTL_SMPC_CTXSW_MODE
0xC0184407	Inout	24	NVGPU_DBG_GPU_IOCTL_PERFBUF_MAP
0x40084408	In	8	NVGPU_DBG_GPU_IOCTL_PERFBUF_UNMAP
0x40084409	In	8	NVGPU_DBG_GPU_IOCTL_PC_SAMPLING
0x4008440A	In	8	NVGPU_DBG_GPU_IOCTL_TIMEOUT
0x8008440B	Out	8	NVGPU_DBG_GPU_IOCTL_GET_TIMEOUT
0x8004440C	Out	4	NVGPU_DBG_GPU_IOCTL_GET_GR_CONTEXT_SIZE
0x0000440D	?	?	NVGPU_DBG_GPU_IOCTL_GET_GR_CONTEXT (uses Ioctl3)

/dev/nvhost-ctrl-gpu

This device is for global (context independent) operations on the gpu.

Value	Direction	Size	Description	Notes
0x80044701	Out	4	NVGPU_GPU_IOCTL_ZCULL_GET_CTX_SIZE
0x80284702	Out	40	NVGPU_GPU_IOCTL_ZCULL_GET_INFO
0x402C4703	In	44	NVGPU_GPU_IOCTL_ZBC_SET_TABLE
0xC0344704	Inout	52	NVGPU_GPU_IOCTL_ZBC_QUERY_TABLE
0xC0B04705	Inout	176	#NVGPU_GPU_IOCTL_GET_CHARACTERISTICS
0xC0184706	Inout	24	NVGPU_GPU_IOCTL_GET_TPC_MASKS
0x40084707	In	8	#NVGPU_GPU_IOCTL_FLUSH_L2
0x4008470E	In	8	NVGPU_GPU_IOCTL_SET_MMUDEBUG_MODE
0x4010470F	In	16	NVGPU_GPU_IOCTL_SET_SM_DEBUG_MODE
0xC0084710	Inout	8	NVGPU_GPU_IOCTL_WAIT_FOR_PAUSE
0x80084711	Out	8	NVGPU_GPU_IOCTL_GET_TPC_EXCEPTION_EN_STATUS
0x80084712	Out	8
0xC0044713	Inout	4
0x80084714	Out	8	#NVGPU_GPU_IOCTL_GET_L2_STATE
0x80044715	Out	4
0x8018471A	Out	24
0xC008471B	Inout	8	NVGPU_GPU_IOCTL_GET_ERROR_CHANNEL_USER_DATA
0xC010471C	Inout	16	NVGPU_GPU_IOCTL_GET_GPU_TIME
0xC108471D	Inout	264	NVGPU_GPU_IOCTL_GET_CPU_TIME_CORRELATION_INFO

NVGPU_GPU_IOCTL_GET_CHARACTERISTICS

Returns the GPU characteristics. Modified to return inline data instead of using a pointer.

 struct __gpu_characteristics {
   u32 __arch;                           // 0x120 (NVGPU_GPU_ARCH_GM200)
   u32 __impl;                           // 0xB (NVGPU_GPU_IMPL_GM20B)
   u32 __rev;                            // 0xA1 (Revision A1)
   u32 __num_gpc;                        // 0x1
   u64 __L2_cache_size;                  // 0x40000
   u64 __on_board_video_memory_size;     // 0x0 (not used)
   u32 __num_tpc_per_gpc;                // 0x2
   u32 __bus_type;                       // 0x20 (NVGPU_GPU_BUS_TYPE_AXI)
   u32 __big_page_size;                  // 0x20000
   u32 __compression_page_size;          // 0x20000
   u32 __pde_coverage_bit_count;         // 0x1B
   u32 __available_big_page_sizes;       // 0x30000
   u32 __gpc_mask;                       // 0x1
   u32 __sm_arch_sm_version;             // 0x503 (Maxwell Generation 5.0.3?)
   u32 __sm_arch_spa_version;            // 0x503 (Maxwell Generation 5.0.3?)
   u32 __sm_arch_warp_count;             // 0x80
   u32 __gpu_va_bit_count;               // 0x28
   u32 __reserved;                       // NULL
   u64 __flags;                          // 0x55
   u32 __twod_class;                     // 0x902D (FERMI_TWOD_A)
   u32 __threed_class;                   // 0xB197 (MAXWELL_B)
   u32 __compute_class;                  // 0xB1C0 (MAXWELL_COMPUTE_B)
   u32 __gpfifo_class;                   // 0xB06F (MAXWELL_CHANNEL_GPFIFO_A)
   u32 __inline_to_memory_class;         // 0xA140 (KEPLER_INLINE_TO_MEMORY_B)
   u32 __dma_copy_class;                 // 0xB0B5 (MAXWELL_DMA_COPY_A)
   u32 __max_fbps_count;                 // 0x1
   u32 __fbp_en_mask;                    // 0x0 (disabled)
   u32 __max_ltc_per_fbp;                // 0x2
   u32 __max_lts_per_ltc;                // 0x1
   u32 __max_tex_per_tpc;                // 0x0 (not supported)
   u32 __max_gpc_count;                  // 0x1
   u32 __rop_l2_en_mask_0;               // 0x21D70 (fuse_status_opt_rop_l2_fbp_r)
   u32 __rop_l2_en_mask_1;               // 0x0
   u64 __chipname;                       // 0x6230326D67 ("gm20b")
   u64 __gr_compbit_store_base_hw;       // 0x0 (not supported)
 };

 struct {
   u64 __gpu_characteristics_buf_size;   // in/out (must not be NULL, but gets overwritten with 0xA0=max_size)
   u64 __gpu_characteristics_buf_addr;   // in (ignored, but must not be NULL)
   struct __gpu_characteristics gc;      // out
 };

NVGPU_GPU_IOCTL_FLUSH_L2

Flushes the GPU L2 cache.

 struct {
   u32 __flush;          // in (l2_flush | l2_invalidate << 1 | fb_flush << 2)
   u32 __reserved;       // in
 };

NVGPU_GPU_IOCTL_GET_L2_STATE

Returns the GPU L2 cache state.

 struct {
   u32 __mask;        // out (always 0x07)
   u32 __flush;       // out (active flush bit field)
 };

Channels

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

Path	Name
/dev/nvhost-gpu
/dev/nvhost-vic	Video Image Compositor
/dev/nvhost-nvdec	Video Decoder
/dev/nvhost-nvjpg	JPEG Decoder

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
0x40080008	8	NVHOST_IOCTL_CHANNEL_SET_CLK_RATE
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_TIMEOUT
0x40084805	8	#NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO
0xC0044807	4	NVGPU_IOCTL_CHANNEL_CYCLE_STATS
0xC0??4808	Variable	#NVGPU_IOCTL_CHANNEL_SUBMIT_GPFIFO
0xC0104809	16	#NVGPU_IOCTL_CHANNEL_ALLOC_OBJ_CTX
0xC010480B	16	NVGPU_IOCTL_CHANNEL_ZCULL_BIND
0xC018480C	24	#NVGPU_IOCTL_CHANNEL_SET_ERROR_NOTIFIER
0x4004480D	4	#NVGPU_IOCTL_CHANNEL_SET_PRIORITY
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	NVGPU_IOCTL_CHANNEL_GET_ERROR_INFO	Only works when the channel is busy
0xC0104817	16	#NVGPU_IOCTL_CHANNEL_GET_ERROR
0x40204818	32	#NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO_EX
0xC0??4819	Variable	#NVGPU_IOCTL_CHANNEL_SUBMIT_GPFIFO_RETRY
0xC020481A	32	#NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO_EX2
0x40084714	8	NVGPU_IOCTL_CHANNEL_SET_USER_DATA	Sets an unknown user context address
0x80084715	8	NVGPU_IOCTL_CHANNEL_GET_USER_DATA	Gets an unknown user context address

NVGPU_IOCTL_CHANNEL_SET_NVMAP_FD

Binds a nvmap object to this channel. Identical to Linux driver.

 struct {
   u32 __nvmap_fd;     // in
 };

NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO

Allocates gpfifo entries. Identical to Linux driver.

 struct {
   u32 __num_entries;     // in
   u32 __flags;           // in
 };

NVGPU_IOCTL_CHANNEL_SUBMIT_GPFIFO

Submits a gpfifo object. Modified to take inline entry objects instead of a pointer.

 struct fence {
   u32 __id;
   u32 __value;
 };
 
 struct gpfifo_entry {
   u32 __entry0;
   u32 __entry1;
 };
 
 struct {
   u64 __gpfifo;                     // in (pointer to gpfifo fence structs; ignored)
   u32 __num_entries;                // in (number of fence objects being submitted)
   u32 __flags;                      // in
   struct fence        __fence_out;  // out (returned new fence object for others to wait on)
   struct gpfifo_entry __entries[];  // in (depends on __num_entries)
 };

NVGPU_IOCTL_CHANNEL_ALLOC_OBJ_CTX

Allocates a graphics context object. Modified to ignore object's ID.

 struct {
   u32 __class_num;    // in (0x902D=2d, 0xB197=3d, 0xB1C0=compute, 0xA140=kepler, 0xB0B5=DMA, 0xB06F=channel_gpfifo)
   u32 __flags;        // in
   u64 __obj_id;       // out (ignored; used for FREE_OBJ_CTX ioctl, which is not supported)
 };

NVGPU_IOCTL_CHANNEL_SET_ERROR_NOTIFIER

Initializes the error notifier for this channel. Identical to Linux driver.

 struct {
   u64 __offset;    // in
   u64 __size;      // in
   u32 __mem;       // in (nvmap object handle)
   u32 __padding;   // in
 };

NVGPU_IOCTL_CHANNEL_SET_PRIORITY

Change channel's priority. Identical to Linux driver.

 struct {
   u32 __priority;    // in (0x32 is low, 0x64 is medium and 0x96 is high)
 };

NVGPU_IOCTL_CHANNEL_ENABLE

Enables the current channel. Identical to Linux driver.

NVGPU_IOCTL_CHANNEL_DISABLE

Disables the current channel. Identical to Linux driver.

NVGPU_IOCTL_CHANNEL_PREEMPT

Clears the FIFO pipe for this channel. Identical to Linux driver.

NVGPU_IOCTL_CHANNEL_FORCE_RESET

Forces the channel to reset. Identical to Linux driver.

NVGPU_IOCTL_CHANNEL_EVENTS_CTRL

Controls event notifications. Modified to take an additional argument.

 struct {
   u32 __cmd;    // in (0=disable, 1=enable, 2=clear)
   u32 __unk;    // in (accepts 1 or 2)
 };

NVGPU_IOCTL_CHANNEL_GET_ERROR

Returns the current error notification caught by the error notifier. Exclusive to the Switch.

 struct {
   u64 __timestamp;    // out (nanoseconds since Jan. 1, 1970)
   u32 __info32;       // out (error code)
   u16 __info16;       // out (additional error info)
   u16 __status;       // inout (always 0xFFFF)
 };

NVGPU_IOCTL_CHANNEL_SUBMIT_GPFIFO_RETRY

Allocates gpfifo entries with additional parameters. Exclusive to the Switch.

 struct {
   u32 __num_entries;     // in
   u32 __flags;           // in
   u32 __unk0;            // in (1 works)
   u32 __unk1;            // in
   u32 __unk2;            // in
   u32 __unk3;            // in
   u32 __unk4;            // in
   u32 __unk5;            // in
 };

NVGPU_IOCTL_CHANNEL_SUBMIT_GPFIFO_EX

Submits a gpfifo object (async version). Exclusive to the Switch.

 struct {
   u64 __gpfifo;                     // in (pointer to gpfifo fence structs; ignored)
   u32 __num_entries;                // in (number of fence objects being submitted)
   u32 __flags;                      // in
   struct fence        __fence_out;  // out (returned new fence object for others to wait on)
   struct gpfifo_entry __entries[];  // in (depends on __num_entries)
 };

NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO_EX2

Allocates gpfifo entries with additional parameters and returns a fence. Exclusive to the Switch.

 struct {
   u32 __num_entries;         // in
   u32 __flags;               // in
   u32 __unk0;                // in (1 works)
   struct fence __fence_out;  // out
   u32 __unk1;                // in
   u32 __unk2;                // in
   u32 __unk3;                // in
 };

nvmemp

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

nvdrvdbg

Cmd	Name
0	#OpenLog
1	#CloseLog
2	#ReadLog

OpenLog

Takes process handle. Returns an fd.

CloseLog

Takes fd and closes it.

ReadLog

Takes fd and reads log into a type-6 buffer.

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	SharedMemoryTooSmall
0x30003	FileOperationFailed
0x3000F	IoctlFailed