The MMIO functions map the global and per-PASID MMIO spaces of the AFU into the address space of the process, as well as moderating access to them. More...

Functions
ocxl_err	global_mmio_open (ocxl_afu *afu)
	Open the global MMIO descriptor on an AFU. More...

ocxl_err	ocxl_mmio_map_advanced (ocxl_afu_h afu, ocxl_mmio_type type, size_t size, int prot, uint64_t flags, off_t offset, ocxl_mmio_h *region)
	Map an MMIO area of an AFU. More...

ocxl_err	ocxl_mmio_map (ocxl_afu_h afu, ocxl_mmio_type type, ocxl_mmio_h *region)
	Map an MMIO area of an AFU. More...

void	ocxl_mmio_unmap (ocxl_mmio_h region)
	Unmap an MMIO region from an AFU. More...

int	ocxl_mmio_get_fd (ocxl_afu_h afu, ocxl_mmio_type type)
	Get a file descriptor for an MMIO area of an AFU. More...

size_t	ocxl_mmio_size (ocxl_afu_h afu, ocxl_mmio_type type)
	Get the size of an MMIO region for an AFU. More...

ocxl_err	ocxl_mmio_get_info (ocxl_mmio_h region, void *address, size_t size)
	Get the address & size of a mapped MMIO region. More...

ocxl_err	ocxl_mmio_read32 (ocxl_mmio_h mmio, off_t offset, ocxl_endian endian, uint32_t *out)
	Read a 32-bit value from an AFU's MMIO region & convert endianess. More...

ocxl_err	ocxl_mmio_read64 (ocxl_mmio_h mmio, off_t offset, ocxl_endian endian, uint64_t *out)
	Read a 64-bit value from an AFU's MMIO region & convert endianess. More...

ocxl_err	ocxl_mmio_write32 (ocxl_mmio_h mmio, off_t offset, ocxl_endian endian, uint32_t value)
	Convert endianess and write a 32-bit value to an AFU's MMIO region. More...

ocxl_err	ocxl_mmio_write64 (ocxl_mmio_h mmio, off_t offset, ocxl_endian endian, uint64_t value)
	Convert endianess and write a 64-bit value to an AFU's MMIO region. More...

Detailed Description

The MMIO functions map the global and per-PASID MMIO spaces of the AFU into the address space of the process, as well as moderating access to them.

Only 32bit & 64bit accesses are supported.

Function Documentation

◆ global_mmio_open()

ocxl_err global_mmio_open ( ocxl_afu * afu )

Open the global MMIO descriptor on an AFU.

Parameters

afu the AFU

Return values

OCXL_NO_DEV if the MMIO descriptor could not be opened

Definition at line 93 of file mmio.c.

◆ ocxl_mmio_get_fd()

int ocxl_mmio_get_fd	(	ocxl_afu_h	afu,
		ocxl_mmio_type	type
	)

Get a file descriptor for an MMIO area of an AFU.

Once obtained, the descriptor may be used to manually MMAP a section of the MMIO area.

See also: ocxl_mmio_size() to get the size of the MMIO areas

Precondition: the AFU has been opened

Parameters

afu	the AFU to operate on
type	the type of MMIO area to map

Returns: the requested descriptor, or -1 if it is not available

Definition at line 329 of file mmio.c.

◆ ocxl_mmio_get_info()

ocxl_err ocxl_mmio_get_info	(	ocxl_mmio_h	region,
		void **	address,
		size_t *	size
	)

Get the address & size of a mapped MMIO region.

Precondition: the AFU has been opened, and the MMIO area mapped

Parameters

region	the MMIO region to get the details for
address	[out] The address of the MMIO region
size	[out] the size of the MMIO region in bytes

Return values

OCXL_OK	if the details were retrieved
OCXL_INVALID_ARGS	if the region is invalid

Definition at line 386 of file mmio.c.

◆ ocxl_mmio_map()

ocxl_err ocxl_mmio_map	(	ocxl_afu_h	afu,
		ocxl_mmio_type	type,
		ocxl_mmio_h *	region
	)

Map an MMIO area of an AFU.

Maps the entire global/per-PASID region of MMIO memory on the AFU with read/write access granted.

Precondition: the AFU has been opened

Parameters

afu	the AFU to operate on
type	the type of MMIO area to map
region	[out] the MMIO region handle

Return values

OCXL_OK	on success
OCXL_NO_MEM	if the map failed
OCXL_NO_CONTEXT	if the AFU has not been opened
OCXL_INVALID_ARGS	if the flags are not valid

Definition at line 291 of file mmio.c.

◆ ocxl_mmio_map_advanced()

ocxl_err ocxl_mmio_map_advanced	(	ocxl_afu_h	afu,
		ocxl_mmio_type	type,
		size_t	size,
		int	prot,
		uint64_t	flags,
		off_t	offset,
		ocxl_mmio_h *	region
	)

Map an MMIO area of an AFU.

Provides finer grain control of MMIO region mapping. Allows for protection parameters to be specified, as well as allowing partial mappings (with PAGE_SIZE granularity).

Precondition: the AFU has been opened

Parameters

	afu	the AFU to operate on
	type	the type of MMIO area to map
	size	the size of the MMIO region to map (or 0 to map the full region)
	prot	the protection parameters as per mmap/mprotect
	flags	Additional flags to modify the map behavior (currently unused, must be 0)
	offset	the offset of the MMIO region to map (or 0 to map the full region), should be a multiple of PAGE_SIZE
[out]	region	the MMIO region handle

Return values

OCXL_OK	on success
OCXL_NO_MEM	if the map failed
OCXL_NO_CONTEXT	if the AFU has not been opened
OCXL_INVALID_ARGS	if the flags are not valid

Definition at line 254 of file mmio.c.

◆ ocxl_mmio_read32()

ocxl_err ocxl_mmio_read32	(	ocxl_mmio_h	mmio,
		off_t	offset,
		ocxl_endian	endian,
		uint32_t *	out
	)

Read a 32-bit value from an AFU's MMIO region & convert endianess.

Read the 32-bit value at offset from the address of the mapped MMIO space, and convert endianess as specified by the endian parameter. Memory barriers are inserted before and after the MMIO operation.

Precondition: the AFU has been opened, and the MMIO area mapped

Parameters

	mmio	the MMIO area to operate on
	offset	A byte address that is aligned on a word (4 byte) boundary. It must be lower than the MMIO size (-4 bytes) reported by ocxl_mmio_size()
	endian	the endianess of the stored data (will be converted to native)
[out]	out	the value that was read

Return values

OCXL_OK	if the value was read
OCXL_NO_CONTEXT	if the MMIO area is not mapped
OCXL_OUT_OF_BOUNDS	if the offset exceeds the available area

Definition at line 617 of file mmio.c.

◆ ocxl_mmio_read64()

ocxl_err ocxl_mmio_read64	(	ocxl_mmio_h	mmio,
		off_t	offset,
		ocxl_endian	endian,
		uint64_t *	out
	)

Read a 64-bit value from an AFU's MMIO region & convert endianess.

Read the 64-bit value at offset from the address of the mapped MMIO space, and convert endianess as specified by the endian parameter. Memory barriers are inserted before and after the MMIO operation.

Precondition: the AFU has been opened, and the MMIO area mapped

Parameters

	mmio	the MMIO area to operate on
	offset	A byte address that is aligned on an 8 byte boundary. It must be lower than the MMIO size (-8 bytes) reported by ocxl_afu_get_mmio_size()
	endian	the endianess of the stored data (will be converted to native)
[out]	out	the value that was read

Return values

OCXL_OK	if the value was read
OCXL_NO_CONTEXT	if the MMIO area is not mapped
OCXL_OUT_OF_BOUNDS	if the offset exceeds the available area

Definition at line 657 of file mmio.c.

◆ ocxl_mmio_size()

size_t ocxl_mmio_size	(	ocxl_afu_h	afu,
		ocxl_mmio_type	type
	)

Get the size of an MMIO region for an AFU.

Parameters

afu	the AFU to get the MMIO size of
type	the type of the MMIO region

Returns: the size of the MMIO region in bytes

Definition at line 356 of file mmio.c.

◆ ocxl_mmio_unmap()

void ocxl_mmio_unmap ( ocxl_mmio_h region )

Unmap an MMIO region from an AFU.

Precondition: the AFU has been opened, and the MMIO area mapped

Parameters

region the MMIO region to unmap

Definition at line 303 of file mmio.c.

◆ ocxl_mmio_write32()

ocxl_err ocxl_mmio_write32	(	ocxl_mmio_h	mmio,
		off_t	offset,
		ocxl_endian	endian,
		uint32_t	value
	)

Convert endianess and write a 32-bit value to an AFU's MMIO region.

Convert endianess and write the 32-bit word at offset from the address of the mapped MMIO space. Memory barriers are inserted before and after the MMIO operation.

Precondition: the AFU has been opened, and the MMIO area mapped

Parameters

mmio	the MMIO area to operate on
offset	A byte address that is aligned on a 4 byte boundary. It must be lower than the MMIO size (-4 bytes) reported by ocxl_mmio_size()
endian	the endianess of the stored data (value will be converted to this before storing it)
value	the value to write

Return values

OCXL_OK	if the value was written
OCXL_NO_CONTEXT	if the MMIO area is not mapped
OCXL_OUT_OF_BOUNDS	if the offset exceeds the available area

Definition at line 697 of file mmio.c.

◆ ocxl_mmio_write64()

ocxl_err ocxl_mmio_write64	(	ocxl_mmio_h	mmio,
		off_t	offset,
		ocxl_endian	endian,
		uint64_t	value
	)

Convert endianess and write a 64-bit value to an AFU's MMIO region.

Convert endianess and write the 32-bit word at offset from the address of the mapped MMIO space. Memory barriers are inserted before and after the MMIO operation.

Precondition: the AFU has been opened, and the MMIO area mapped

Parameters

mmio	the MMIO area to operate on
offset	A byte address that is aligned on an 8 byte boundary. It must be lower than the MMIO size (-8 bytes) reported by ocxl_mmio_size()
endian	the endianess of the stored data (value will be converted to this before storing it)
value	the value to write

Return values

OCXL_OK	if the value was written
OCXL_NO_CONTEXT	if the MMIO area is not mapped
OCXL_OUT_OF_BOUNDS	if the offset exceeds the available area

Definition at line 732 of file mmio.c.

Functions

Detailed Description

Function Documentation

◆ global_mmio_open()

◆ ocxl_mmio_get_fd()

◆ ocxl_mmio_get_info()

◆ ocxl_mmio_map()

◆ ocxl_mmio_map_advanced()

◆ ocxl_mmio_read32()

◆ ocxl_mmio_read64()

◆ ocxl_mmio_size()

◆ ocxl_mmio_unmap()

◆ ocxl_mmio_write32()

◆ ocxl_mmio_write64()