freebsd-dev/sys/dev/ntb/ntb.h

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/*-
* Copyright (c) 2016 Alexander Motin <mav@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _NTB_H_
#define _NTB_H_
#include "ntb_if.h"
extern devclass_t ntb_hw_devclass;
SYSCTL_DECL(_hw_ntb);
int ntb_register_device(device_t ntb);
int ntb_unregister_device(device_t ntb);
/*
* ntb_link_event() - notify driver context of a change in link status
* @ntb: NTB device context
*
* Notify the driver context that the link status may have changed. The driver
* should call intb_link_is_up() to get the current status.
*/
void ntb_link_event(device_t ntb);
/*
* ntb_db_event() - notify driver context of a doorbell event
* @ntb: NTB device context
* @vector: Interrupt vector number
*
* Notify the driver context of a doorbell event. If hardware supports
* multiple interrupt vectors for doorbells, the vector number indicates which
* vector received the interrupt. The vector number is relative to the first
* vector used for doorbells, starting at zero, and must be less than
* ntb_db_vector_count(). The driver may call ntb_db_read() to check which
* doorbell bits need service, and ntb_db_vector_mask() to determine which of
* those bits are associated with the vector number.
*/
void ntb_db_event(device_t ntb, uint32_t vec);
/*
* ntb_link_is_up() - get the current ntb link state
* @ntb: NTB device context
* @speed: OUT - The link speed expressed as PCIe generation number
* @width: OUT - The link width expressed as the number of PCIe lanes
*
* RETURNS: true or false based on the hardware link state
*/
bool ntb_link_is_up(device_t ntb, enum ntb_speed *speed, enum ntb_width *width);
/*
* ntb_link_enable() - enable the link on the secondary side of the ntb
* @ntb: NTB device context
* @max_speed: The maximum link speed expressed as PCIe generation number[0]
* @max_width: The maximum link width expressed as the number of PCIe lanes[0]
*
* Enable the link on the secondary side of the ntb. This can only be done
* from the primary side of the ntb in primary or b2b topology. The ntb device
* should train the link to its maximum speed and width, or the requested speed
* and width, whichever is smaller, if supported.
*
* Return: Zero on success, otherwise an error number.
*
* [0]: Only NTB_SPEED_AUTO and NTB_WIDTH_AUTO are valid inputs; other speed
* and width input will be ignored.
*/
int ntb_link_enable(device_t ntb, enum ntb_speed speed, enum ntb_width width);
/*
* ntb_link_disable() - disable the link on the secondary side of the ntb
* @ntb: NTB device context
*
* Disable the link on the secondary side of the ntb. This can only be done
* from the primary side of the ntb in primary or b2b topology. The ntb device
* should disable the link. Returning from this call must indicate that a
* barrier has passed, though with no more writes may pass in either direction
* across the link, except if this call returns an error number.
*
* Return: Zero on success, otherwise an error number.
*/
int ntb_link_disable(device_t ntb);
/*
* get enable status of the link on the secondary side of the ntb
*/
bool ntb_link_enabled(device_t ntb);
/*
* ntb_set_ctx() - associate a driver context with an ntb device
* @ntb: NTB device context
* @ctx: Driver context
* @ctx_ops: Driver context operations
*
* Associate a driver context and operations with a ntb device. The context is
* provided by the client driver, and the driver may associate a different
* context with each ntb device.
*
* Return: Zero if the context is associated, otherwise an error number.
*/
int ntb_set_ctx(device_t ntb, void *ctx, const struct ntb_ctx_ops *ctx_ops);
/*
* ntb_set_ctx() - get a driver context associated with an ntb device
* @ntb: NTB device context
* @ctx_ops: Driver context operations
*
* Get a driver context and operations associated with a ntb device.
*/
void * ntb_get_ctx(device_t ntb, const struct ntb_ctx_ops **ctx_ops);
/*
* ntb_clear_ctx() - disassociate any driver context from an ntb device
* @ntb: NTB device context
*
* Clear any association that may exist between a driver context and the ntb
* device.
*/
void ntb_clear_ctx(device_t ntb);
/*
* ntb_mw_count() - Get the number of memory windows available for KPI
* consumers.
*
* (Excludes any MW wholly reserved for register access.)
*/
uint8_t ntb_mw_count(device_t ntb);
/*
* ntb_mw_get_range() - get the range of a memory window
* @ntb: NTB device context
* @idx: Memory window number
* @base: OUT - the base address for mapping the memory window
* @size: OUT - the size for mapping the memory window
* @align: OUT - the base alignment for translating the memory window
* @align_size: OUT - the size alignment for translating the memory window
*
* Get the range of a memory window. NULL may be given for any output
* parameter if the value is not needed. The base and size may be used for
* mapping the memory window, to access the peer memory. The alignment and
* size may be used for translating the memory window, for the peer to access
* memory on the local system.
*
* Return: Zero on success, otherwise an error number.
*/
int ntb_mw_get_range(device_t ntb, unsigned mw_idx, vm_paddr_t *base,
caddr_t *vbase, size_t *size, size_t *align, size_t *align_size,
bus_addr_t *plimit);
/*
* ntb_mw_set_trans() - set the translation of a memory window
* @ntb: NTB device context
* @idx: Memory window number
* @addr: The dma address local memory to expose to the peer
* @size: The size of the local memory to expose to the peer
*
* Set the translation of a memory window. The peer may access local memory
* through the window starting at the address, up to the size. The address
* must be aligned to the alignment specified by ntb_mw_get_range(). The size
* must be aligned to the size alignment specified by ntb_mw_get_range(). The
* address must be below the plimit specified by ntb_mw_get_range() (i.e. for
* 32-bit BARs).
*
* Return: Zero on success, otherwise an error number.
*/
int ntb_mw_set_trans(device_t ntb, unsigned mw_idx, bus_addr_t addr,
size_t size);
/*
* ntb_mw_clear_trans() - clear the translation of a memory window
* @ntb: NTB device context
* @idx: Memory window number
*
* Clear the translation of a memory window. The peer may no longer access
* local memory through the window.
*
* Return: Zero on success, otherwise an error number.
*/
int ntb_mw_clear_trans(device_t ntb, unsigned mw_idx);
/*
* ntb_mw_get_wc - Get the write-combine status of a memory window
*
* Returns: Zero on success, setting *wc; otherwise an error number (e.g. if
* idx is an invalid memory window).
*
* Mode is a VM_MEMATTR_* type.
*/
int ntb_mw_get_wc(device_t ntb, unsigned mw_idx, vm_memattr_t *mode);
/*
* ntb_mw_set_wc - Set the write-combine status of a memory window
*
* If 'mode' matches the current status, this does nothing and succeeds. Mode
* is a VM_MEMATTR_* type.
*
* Returns: Zero on success, setting the caching attribute on the virtual
* mapping of the BAR; otherwise an error number (e.g. if idx is an invalid
* memory window, or if changing the caching attribute fails).
*/
int ntb_mw_set_wc(device_t ntb, unsigned mw_idx, vm_memattr_t mode);
/*
* ntb_spad_count() - get the total scratch regs usable
* @ntb: pointer to ntb_softc instance
*
* This function returns the max 32bit scratchpad registers usable by the
* upper layer.
*
* RETURNS: total number of scratch pad registers available
*/
uint8_t ntb_spad_count(device_t ntb);
/*
* ntb_get_max_spads() - zero local scratch registers
* @ntb: pointer to ntb_softc instance
*
* This functions overwrites all local scratchpad registers with zeroes.
*/
void ntb_spad_clear(device_t ntb);
/*
* ntb_spad_write() - write to the secondary scratchpad register
* @ntb: pointer to ntb_softc instance
* @idx: index to the scratchpad register, 0 based
* @val: the data value to put into the register
*
* This function allows writing of a 32bit value to the indexed scratchpad
* register. The register resides on the secondary (external) side.
*
* RETURNS: An appropriate ERRNO error value on error, or zero for success.
*/
int ntb_spad_write(device_t ntb, unsigned int idx, uint32_t val);
/*
* ntb_spad_read() - read from the primary scratchpad register
* @ntb: pointer to ntb_softc instance
* @idx: index to scratchpad register, 0 based
* @val: pointer to 32bit integer for storing the register value
*
* This function allows reading of the 32bit scratchpad register on
* the primary (internal) side.
*
* RETURNS: An appropriate ERRNO error value on error, or zero for success.
*/
int ntb_spad_read(device_t ntb, unsigned int idx, uint32_t *val);
/*
* ntb_peer_spad_write() - write to the secondary scratchpad register
* @ntb: pointer to ntb_softc instance
* @idx: index to the scratchpad register, 0 based
* @val: the data value to put into the register
*
* This function allows writing of a 32bit value to the indexed scratchpad
* register. The register resides on the secondary (external) side.
*
* RETURNS: An appropriate ERRNO error value on error, or zero for success.
*/
int ntb_peer_spad_write(device_t ntb, unsigned int idx, uint32_t val);
/*
* ntb_peer_spad_read() - read from the primary scratchpad register
* @ntb: pointer to ntb_softc instance
* @idx: index to scratchpad register, 0 based
* @val: pointer to 32bit integer for storing the register value
*
* This function allows reading of the 32bit scratchpad register on
* the primary (internal) side.
*
* RETURNS: An appropriate ERRNO error value on error, or zero for success.
*/
int ntb_peer_spad_read(device_t ntb, unsigned int idx, uint32_t *val);
/*
* ntb_db_valid_mask() - get a mask of doorbell bits supported by the ntb
* @ntb: NTB device context
*
* Hardware may support different number or arrangement of doorbell bits.
*
* Return: A mask of doorbell bits supported by the ntb.
*/
uint64_t ntb_db_valid_mask(device_t ntb);
/*
* ntb_db_vector_count() - get the number of doorbell interrupt vectors
* @ntb: NTB device context.
*
* Hardware may support different number of interrupt vectors.
*
* Return: The number of doorbell interrupt vectors.
*/
int ntb_db_vector_count(device_t ntb);
/*
* ntb_db_vector_mask() - get a mask of doorbell bits serviced by a vector
* @ntb: NTB device context
* @vector: Doorbell vector number
*
* Each interrupt vector may have a different number or arrangement of bits.
*
* Return: A mask of doorbell bits serviced by a vector.
*/
uint64_t ntb_db_vector_mask(device_t ntb, uint32_t vector);
/*
* ntb_peer_db_addr() - address and size of the peer doorbell register
* @ntb: NTB device context.
* @db_addr: OUT - The address of the peer doorbell register.
* @db_size: OUT - The number of bytes to write the peer doorbell register.
*
* Return the address of the peer doorbell register. This may be used, for
* example, by drivers that offload memory copy operations to a dma engine.
* The drivers may wish to ring the peer doorbell at the completion of memory
* copy operations. For efficiency, and to simplify ordering of operations
* between the dma memory copies and the ringing doorbell, the driver may
* append one additional dma memory copy with the doorbell register as the
* destination, after the memory copy operations.
*
* Return: Zero on success, otherwise an error number.
*
* Note that writing the peer doorbell via a memory window will *not* generate
* an interrupt on the remote host; that must be done separately.
*/
int ntb_peer_db_addr(device_t ntb, bus_addr_t *db_addr, vm_size_t *db_size);
/*
* ntb_db_clear() - clear bits in the local doorbell register
* @ntb: NTB device context.
* @db_bits: Doorbell bits to clear.
*
* Clear bits in the local doorbell register, arming the bits for the next
* doorbell.
*
* Return: Zero on success, otherwise an error number.
*/
void ntb_db_clear(device_t ntb, uint64_t bits);
/*
* ntb_db_clear_mask() - clear bits in the local doorbell mask
* @ntb: NTB device context.
* @db_bits: Doorbell bits to clear.
*
* Clear bits in the local doorbell mask register, allowing doorbell interrupts
* from being generated for those doorbell bits. If a doorbell bit is already
* set at the time the mask is cleared, and the corresponding mask bit is
* changed from set to clear, then the ntb driver must ensure that
* ntb_db_event() is called. If the hardware does not generate the interrupt
* on clearing the mask bit, then the driver must call ntb_db_event() anyway.
*
* Return: Zero on success, otherwise an error number.
*/
void ntb_db_clear_mask(device_t ntb, uint64_t bits);
/*
* ntb_db_read() - read the local doorbell register
* @ntb: NTB device context.
*
* Read the local doorbell register, and return the bits that are set.
*
* Return: The bits currently set in the local doorbell register.
*/
uint64_t ntb_db_read(device_t ntb);
/*
* ntb_db_set_mask() - set bits in the local doorbell mask
* @ntb: NTB device context.
* @db_bits: Doorbell mask bits to set.
*
* Set bits in the local doorbell mask register, preventing doorbell interrupts
* from being generated for those doorbell bits. Bits that were already set
* must remain set.
*
* Return: Zero on success, otherwise an error number.
*/
void ntb_db_set_mask(device_t ntb, uint64_t bits);
/*
* ntb_peer_db_set() - Set the doorbell on the secondary/external side
* @ntb: pointer to ntb_softc instance
* @bit: doorbell bits to ring
*
* This function allows triggering of a doorbell on the secondary/external
* side that will initiate an interrupt on the remote host
*/
void ntb_peer_db_set(device_t ntb, uint64_t bits);
#endif /* _NTB_H_ */