Current File : //usr/src/kernels/3.10.0-1160.83.1.el7.centos.plus.x86_64/include/linux/ntb.h
/*
* This file is provided under a dual BSD/GPLv2 license. When using or
* redistributing this file, you may do so under either license.
*
* GPL LICENSE SUMMARY
*
* Copyright (C) 2015 EMC Corporation. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* BSD LICENSE
*
* Copyright (C) 2015 EMC Corporation. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copy
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
* OWNER 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.
*
* PCIe NTB Linux driver
*
* Contact Information:
* Allen Hubbe <Allen.Hubbe@emc.com>
*/
#ifndef _NTB_H_
#define _NTB_H_
#include <linux/completion.h>
#include <linux/device.h>
struct ntb_client;
struct ntb_dev;
struct pci_dev;
/**
* enum ntb_topo - NTB connection topology
* @NTB_TOPO_NONE: Topology is unknown or invalid.
* @NTB_TOPO_PRI: On primary side of local ntb.
* @NTB_TOPO_SEC: On secondary side of remote ntb.
* @NTB_TOPO_B2B_USD: On primary side of local ntb upstream of remote ntb.
* @NTB_TOPO_B2B_DSD: On primary side of local ntb downstream of remote ntb.
*/
enum ntb_topo {
NTB_TOPO_NONE = -1,
NTB_TOPO_PRI,
NTB_TOPO_SEC,
NTB_TOPO_B2B_USD,
NTB_TOPO_B2B_DSD,
};
static inline int ntb_topo_is_b2b(enum ntb_topo topo)
{
switch ((int)topo) {
case NTB_TOPO_B2B_USD:
case NTB_TOPO_B2B_DSD:
return 1;
}
return 0;
}
static inline char *ntb_topo_string(enum ntb_topo topo)
{
switch (topo) {
case NTB_TOPO_NONE: return "NTB_TOPO_NONE";
case NTB_TOPO_PRI: return "NTB_TOPO_PRI";
case NTB_TOPO_SEC: return "NTB_TOPO_SEC";
case NTB_TOPO_B2B_USD: return "NTB_TOPO_B2B_USD";
case NTB_TOPO_B2B_DSD: return "NTB_TOPO_B2B_DSD";
}
return "NTB_TOPO_INVALID";
}
/**
* enum ntb_speed - NTB link training speed
* @NTB_SPEED_AUTO: Request the max supported speed.
* @NTB_SPEED_NONE: Link is not trained to any speed.
* @NTB_SPEED_GEN1: Link is trained to gen1 speed.
* @NTB_SPEED_GEN2: Link is trained to gen2 speed.
* @NTB_SPEED_GEN3: Link is trained to gen3 speed.
*/
enum ntb_speed {
NTB_SPEED_AUTO = -1,
NTB_SPEED_NONE = 0,
NTB_SPEED_GEN1 = 1,
NTB_SPEED_GEN2 = 2,
NTB_SPEED_GEN3 = 3,
};
/**
* enum ntb_width - NTB link training width
* @NTB_WIDTH_AUTO: Request the max supported width.
* @NTB_WIDTH_NONE: Link is not trained to any width.
* @NTB_WIDTH_1: Link is trained to 1 lane width.
* @NTB_WIDTH_2: Link is trained to 2 lane width.
* @NTB_WIDTH_4: Link is trained to 4 lane width.
* @NTB_WIDTH_8: Link is trained to 8 lane width.
* @NTB_WIDTH_12: Link is trained to 12 lane width.
* @NTB_WIDTH_16: Link is trained to 16 lane width.
* @NTB_WIDTH_32: Link is trained to 32 lane width.
*/
enum ntb_width {
NTB_WIDTH_AUTO = -1,
NTB_WIDTH_NONE = 0,
NTB_WIDTH_1 = 1,
NTB_WIDTH_2 = 2,
NTB_WIDTH_4 = 4,
NTB_WIDTH_8 = 8,
NTB_WIDTH_12 = 12,
NTB_WIDTH_16 = 16,
NTB_WIDTH_32 = 32,
};
/**
* struct ntb_client_ops - ntb client operations
* @probe: Notify client of a new device.
* @remove: Notify client to remove a device.
*/
struct ntb_client_ops {
int (*probe)(struct ntb_client *client, struct ntb_dev *ntb);
void (*remove)(struct ntb_client *client, struct ntb_dev *ntb);
};
static inline int ntb_client_ops_is_valid(const struct ntb_client_ops *ops)
{
/* commented callbacks are not required: */
return
ops->probe &&
ops->remove &&
1;
}
/**
* struct ntb_ctx_ops - ntb driver context operations
* @link_event: See ntb_link_event().
* @db_event: See ntb_db_event().
*/
struct ntb_ctx_ops {
void (*link_event)(void *ctx);
void (*db_event)(void *ctx, int db_vector);
};
static inline int ntb_ctx_ops_is_valid(const struct ntb_ctx_ops *ops)
{
/* commented callbacks are not required: */
return
/* ops->link_event && */
/* ops->db_event && */
1;
}
/**
* struct ntb_ctx_ops - ntb device operations
* @mw_count: See ntb_mw_count().
* @mw_get_range: See ntb_mw_get_range().
* @mw_set_trans: See ntb_mw_set_trans().
* @mw_clear_trans: See ntb_mw_clear_trans().
* @link_is_up: See ntb_link_is_up().
* @link_enable: See ntb_link_enable().
* @link_disable: See ntb_link_disable().
* @db_is_unsafe: See ntb_db_is_unsafe().
* @db_valid_mask: See ntb_db_valid_mask().
* @db_vector_count: See ntb_db_vector_count().
* @db_vector_mask: See ntb_db_vector_mask().
* @db_read: See ntb_db_read().
* @db_set: See ntb_db_set().
* @db_clear: See ntb_db_clear().
* @db_read_mask: See ntb_db_read_mask().
* @db_set_mask: See ntb_db_set_mask().
* @db_clear_mask: See ntb_db_clear_mask().
* @peer_db_addr: See ntb_peer_db_addr().
* @peer_db_read: See ntb_peer_db_read().
* @peer_db_set: See ntb_peer_db_set().
* @peer_db_clear: See ntb_peer_db_clear().
* @peer_db_read_mask: See ntb_peer_db_read_mask().
* @peer_db_set_mask: See ntb_peer_db_set_mask().
* @peer_db_clear_mask: See ntb_peer_db_clear_mask().
* @spad_is_unsafe: See ntb_spad_is_unsafe().
* @spad_count: See ntb_spad_count().
* @spad_read: See ntb_spad_read().
* @spad_write: See ntb_spad_write().
* @peer_spad_addr: See ntb_peer_spad_addr().
* @peer_spad_read: See ntb_peer_spad_read().
* @peer_spad_write: See ntb_peer_spad_write().
*/
struct ntb_dev_ops {
int (*mw_count)(struct ntb_dev *ntb);
int (*mw_get_range)(struct ntb_dev *ntb, int idx,
phys_addr_t *base, resource_size_t *size,
resource_size_t *align, resource_size_t *align_size);
int (*mw_set_trans)(struct ntb_dev *ntb, int idx,
dma_addr_t addr, resource_size_t size);
int (*mw_clear_trans)(struct ntb_dev *ntb, int idx);
int (*link_is_up)(struct ntb_dev *ntb,
enum ntb_speed *speed, enum ntb_width *width);
int (*link_enable)(struct ntb_dev *ntb,
enum ntb_speed max_speed, enum ntb_width max_width);
int (*link_disable)(struct ntb_dev *ntb);
int (*db_is_unsafe)(struct ntb_dev *ntb);
u64 (*db_valid_mask)(struct ntb_dev *ntb);
int (*db_vector_count)(struct ntb_dev *ntb);
u64 (*db_vector_mask)(struct ntb_dev *ntb, int db_vector);
u64 (*db_read)(struct ntb_dev *ntb);
int (*db_set)(struct ntb_dev *ntb, u64 db_bits);
int (*db_clear)(struct ntb_dev *ntb, u64 db_bits);
u64 (*db_read_mask)(struct ntb_dev *ntb);
int (*db_set_mask)(struct ntb_dev *ntb, u64 db_bits);
int (*db_clear_mask)(struct ntb_dev *ntb, u64 db_bits);
int (*peer_db_addr)(struct ntb_dev *ntb,
phys_addr_t *db_addr, resource_size_t *db_size);
u64 (*peer_db_read)(struct ntb_dev *ntb);
int (*peer_db_set)(struct ntb_dev *ntb, u64 db_bits);
int (*peer_db_clear)(struct ntb_dev *ntb, u64 db_bits);
u64 (*peer_db_read_mask)(struct ntb_dev *ntb);
int (*peer_db_set_mask)(struct ntb_dev *ntb, u64 db_bits);
int (*peer_db_clear_mask)(struct ntb_dev *ntb, u64 db_bits);
int (*spad_is_unsafe)(struct ntb_dev *ntb);
int (*spad_count)(struct ntb_dev *ntb);
u32 (*spad_read)(struct ntb_dev *ntb, int idx);
int (*spad_write)(struct ntb_dev *ntb, int idx, u32 val);
int (*peer_spad_addr)(struct ntb_dev *ntb, int idx,
phys_addr_t *spad_addr);
u32 (*peer_spad_read)(struct ntb_dev *ntb, int idx);
int (*peer_spad_write)(struct ntb_dev *ntb, int idx, u32 val);
};
static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops)
{
/* commented callbacks are not required: */
return
ops->mw_count &&
ops->mw_get_range &&
ops->mw_set_trans &&
/* ops->mw_clear_trans && */
ops->link_is_up &&
ops->link_enable &&
ops->link_disable &&
/* ops->db_is_unsafe && */
ops->db_valid_mask &&
/* both set, or both unset */
(!ops->db_vector_count == !ops->db_vector_mask) &&
ops->db_read &&
/* ops->db_set && */
ops->db_clear &&
/* ops->db_read_mask && */
ops->db_set_mask &&
ops->db_clear_mask &&
/* ops->peer_db_addr && */
/* ops->peer_db_read && */
ops->peer_db_set &&
/* ops->peer_db_clear && */
/* ops->peer_db_read_mask && */
/* ops->peer_db_set_mask && */
/* ops->peer_db_clear_mask && */
/* ops->spad_is_unsafe && */
ops->spad_count &&
ops->spad_read &&
ops->spad_write &&
/* ops->peer_spad_addr && */
/* ops->peer_spad_read && */
ops->peer_spad_write &&
1;
}
/**
* struct ntb_client - client interested in ntb devices
* @drv: Linux driver object.
* @ops: See &ntb_client_ops.
*/
struct ntb_client {
struct device_driver drv;
const struct ntb_client_ops ops;
};
#define drv_ntb_client(__drv) container_of((__drv), struct ntb_client, drv)
/**
* struct ntb_device - ntb device
* @dev: Linux device object.
* @pdev: Pci device entry of the ntb.
* @topo: Detected topology of the ntb.
* @ops: See &ntb_dev_ops.
* @ctx: See &ntb_ctx_ops.
* @ctx_ops: See &ntb_ctx_ops.
*/
struct ntb_dev {
struct device dev;
struct pci_dev *pdev;
enum ntb_topo topo;
const struct ntb_dev_ops *ops;
void *ctx;
const struct ntb_ctx_ops *ctx_ops;
/* private: */
/* synchronize setting, clearing, and calling ctx_ops */
spinlock_t ctx_lock;
/* block unregister until device is fully released */
struct completion released;
};
#define dev_ntb(__dev) container_of((__dev), struct ntb_dev, dev)
/**
* ntb_register_client() - register a client for interest in ntb devices
* @client: Client context.
*
* The client will be added to the list of clients interested in ntb devices.
* The client will be notified of any ntb devices that are not already
* associated with a client, or if ntb devices are registered later.
*
* Return: Zero if the client is registered, otherwise an error number.
*/
#define ntb_register_client(client) \
__ntb_register_client((client), THIS_MODULE, KBUILD_MODNAME)
int __ntb_register_client(struct ntb_client *client, struct module *mod,
const char *mod_name);
/**
* ntb_unregister_client() - unregister a client for interest in ntb devices
* @client: Client context.
*
* The client will be removed from the list of clients interested in ntb
* devices. If any ntb devices are associated with the client, the client will
* be notified to remove those devices.
*/
void ntb_unregister_client(struct ntb_client *client);
#define module_ntb_client(__ntb_client) \
module_driver(__ntb_client, ntb_register_client, \
ntb_unregister_client)
/**
* ntb_register_device() - register a ntb device
* @ntb: NTB device context.
*
* The device will be added to the list of ntb devices. If any clients are
* interested in ntb devices, each client will be notified of the ntb device,
* until at most one client accepts the device.
*
* Return: Zero if the device is registered, otherwise an error number.
*/
int ntb_register_device(struct ntb_dev *ntb);
/**
* ntb_register_device() - unregister a ntb device
* @ntb: NTB device context.
*
* The device will be removed from the list of ntb devices. If the ntb device
* is associated with a client, the client will be notified to remove the
* device.
*/
void ntb_unregister_device(struct ntb_dev *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(struct ntb_dev *ntb, void *ctx,
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(struct ntb_dev *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 ntb_link_is_up() to get the current status.
*/
void ntb_link_event(struct ntb_dev *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(struct ntb_dev *ntb, int vector);
/**
* ntb_mw_count() - get the number of memory windows
* @ntb: NTB device context.
*
* Hardware and topology may support a different number of memory windows.
*
* Return: the number of memory windows.
*/
static inline int ntb_mw_count(struct ntb_dev *ntb)
{
return ntb->ops->mw_count(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.
*/
static inline int ntb_mw_get_range(struct ntb_dev *ntb, int idx,
phys_addr_t *base, resource_size_t *size,
resource_size_t *align, resource_size_t *align_size)
{
return ntb->ops->mw_get_range(ntb, idx, base, size,
align, align_size);
}
/**
* 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().
*
* Return: Zero on success, otherwise an error number.
*/
static inline int ntb_mw_set_trans(struct ntb_dev *ntb, int idx,
dma_addr_t addr, resource_size_t size)
{
return ntb->ops->mw_set_trans(ntb, idx, addr, 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.
*/
static inline int ntb_mw_clear_trans(struct ntb_dev *ntb, int idx)
{
if (!ntb->ops->mw_clear_trans)
return ntb->ops->mw_set_trans(ntb, idx, 0, 0);
return ntb->ops->mw_clear_trans(ntb, idx);
}
/**
* 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.
*
* 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().
*
* Return: One if the link is up, zero if the link is down, otherwise a
* negative value indicating the error number.
*/
static inline int ntb_link_is_up(struct ntb_dev *ntb,
enum ntb_speed *speed, enum ntb_width *width)
{
return ntb->ops->link_is_up(ntb, speed, 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.
* @max_width: The maximum link width expressed as the number of PCIe lanes.
*
* 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.
*/
static inline int ntb_link_enable(struct ntb_dev *ntb,
enum ntb_speed max_speed,
enum ntb_width max_width)
{
return ntb->ops->link_enable(ntb, max_speed, max_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.
*/
static inline int ntb_link_disable(struct ntb_dev *ntb)
{
return ntb->ops->link_disable(ntb);
}
/**
* ntb_db_is_unsafe() - check if it is safe to use hardware doorbell
* @ntb: NTB device context.
*
* It is possible for some ntb hardware to be affected by errata. Hardware
* drivers can advise clients to avoid using doorbells. Clients may ignore
* this advice, though caution is recommended.
*
* Return: Zero if it is safe to use doorbells, or One if it is not safe.
*/
static inline int ntb_db_is_unsafe(struct ntb_dev *ntb)
{
if (!ntb->ops->db_is_unsafe)
return 0;
return ntb->ops->db_is_unsafe(ntb);
}
/**
* 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.
*/
static inline u64 ntb_db_valid_mask(struct ntb_dev *ntb)
{
return ntb->ops->db_valid_mask(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.
*/
static inline int ntb_db_vector_count(struct ntb_dev *ntb)
{
if (!ntb->ops->db_vector_count)
return 1;
return ntb->ops->db_vector_count(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.
*/
static inline u64 ntb_db_vector_mask(struct ntb_dev *ntb, int vector)
{
if (!ntb->ops->db_vector_mask)
return ntb_db_valid_mask(ntb);
return ntb->ops->db_vector_mask(ntb, vector);
}
/**
* 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.
*/
static inline u64 ntb_db_read(struct ntb_dev *ntb)
{
return ntb->ops->db_read(ntb);
}
/**
* ntb_db_set() - set bits in the local doorbell register
* @ntb: NTB device context.
* @db_bits: Doorbell bits to set.
*
* Set bits in the local doorbell register, which may generate a local doorbell
* interrupt. Bits that were already set must remain set.
*
* This is unusual, and hardware may not support it.
*
* Return: Zero on success, otherwise an error number.
*/
static inline int ntb_db_set(struct ntb_dev *ntb, u64 db_bits)
{
if (!ntb->ops->db_set)
return -EINVAL;
return ntb->ops->db_set(ntb, db_bits);
}
/**
* 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.
*/
static inline int ntb_db_clear(struct ntb_dev *ntb, u64 db_bits)
{
return ntb->ops->db_clear(ntb, db_bits);
}
/**
* ntb_db_read_mask() - read the local doorbell mask
* @ntb: NTB device context.
*
* Read the local doorbell mask register, and return the bits that are set.
*
* This is unusual, though hardware is likely to support it.
*
* Return: The bits currently set in the local doorbell mask register.
*/
static inline u64 ntb_db_read_mask(struct ntb_dev *ntb)
{
if (!ntb->ops->db_read_mask)
return 0;
return ntb->ops->db_read_mask(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.
*/
static inline int ntb_db_set_mask(struct ntb_dev *ntb, u64 db_bits)
{
return ntb->ops->db_set_mask(ntb, db_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.
*/
static inline int ntb_db_clear_mask(struct ntb_dev *ntb, u64 db_bits)
{
return ntb->ops->db_clear_mask(ntb, db_bits);
}
/**
* 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.
*/
static inline int ntb_peer_db_addr(struct ntb_dev *ntb,
phys_addr_t *db_addr,
resource_size_t *db_size)
{
if (!ntb->ops->peer_db_addr)
return -EINVAL;
return ntb->ops->peer_db_addr(ntb, db_addr, db_size);
}
/**
* ntb_peer_db_read() - read the peer doorbell register
* @ntb: NTB device context.
*
* Read the peer doorbell register, and return the bits that are set.
*
* This is unusual, and hardware may not support it.
*
* Return: The bits currently set in the peer doorbell register.
*/
static inline u64 ntb_peer_db_read(struct ntb_dev *ntb)
{
if (!ntb->ops->peer_db_read)
return 0;
return ntb->ops->peer_db_read(ntb);
}
/**
* ntb_peer_db_set() - set bits in the peer doorbell register
* @ntb: NTB device context.
* @db_bits: Doorbell bits to set.
*
* Set bits in the peer doorbell register, which may generate a peer doorbell
* interrupt. Bits that were already set must remain set.
*
* Return: Zero on success, otherwise an error number.
*/
static inline int ntb_peer_db_set(struct ntb_dev *ntb, u64 db_bits)
{
return ntb->ops->peer_db_set(ntb, db_bits);
}
/**
* ntb_peer_db_clear() - clear bits in the peer doorbell register
* @ntb: NTB device context.
* @db_bits: Doorbell bits to clear.
*
* Clear bits in the peer doorbell register, arming the bits for the next
* doorbell.
*
* This is unusual, and hardware may not support it.
*
* Return: Zero on success, otherwise an error number.
*/
static inline int ntb_peer_db_clear(struct ntb_dev *ntb, u64 db_bits)
{
if (!ntb->ops->db_clear)
return -EINVAL;
return ntb->ops->peer_db_clear(ntb, db_bits);
}
/**
* ntb_peer_db_read_mask() - read the peer doorbell mask
* @ntb: NTB device context.
*
* Read the peer doorbell mask register, and return the bits that are set.
*
* This is unusual, and hardware may not support it.
*
* Return: The bits currently set in the peer doorbell mask register.
*/
static inline u64 ntb_peer_db_read_mask(struct ntb_dev *ntb)
{
if (!ntb->ops->db_read_mask)
return 0;
return ntb->ops->peer_db_read_mask(ntb);
}
/**
* ntb_peer_db_set_mask() - set bits in the peer doorbell mask
* @ntb: NTB device context.
* @db_bits: Doorbell mask bits to set.
*
* Set bits in the peer doorbell mask register, preventing doorbell interrupts
* from being generated for those doorbell bits. Bits that were already set
* must remain set.
*
* This is unusual, and hardware may not support it.
*
* Return: Zero on success, otherwise an error number.
*/
static inline int ntb_peer_db_set_mask(struct ntb_dev *ntb, u64 db_bits)
{
if (!ntb->ops->db_set_mask)
return -EINVAL;
return ntb->ops->peer_db_set_mask(ntb, db_bits);
}
/**
* ntb_peer_db_clear_mask() - clear bits in the peer doorbell mask
* @ntb: NTB device context.
* @db_bits: Doorbell bits to clear.
*
* Clear bits in the peer doorbell mask register, allowing doorbell interrupts
* from being generated for those doorbell bits. If the hardware does not
* generate the interrupt on clearing the mask bit, then the driver should not
* implement this function!
*
* This is unusual, and hardware may not support it.
*
* Return: Zero on success, otherwise an error number.
*/
static inline int ntb_peer_db_clear_mask(struct ntb_dev *ntb, u64 db_bits)
{
if (!ntb->ops->db_clear_mask)
return -EINVAL;
return ntb->ops->peer_db_clear_mask(ntb, db_bits);
}
/**
* ntb_spad_is_unsafe() - check if it is safe to use the hardware scratchpads
* @ntb: NTB device context.
*
* It is possible for some ntb hardware to be affected by errata. Hardware
* drivers can advise clients to avoid using scratchpads. Clients may ignore
* this advice, though caution is recommended.
*
* Return: Zero if it is safe to use scratchpads, or One if it is not safe.
*/
static inline int ntb_spad_is_unsafe(struct ntb_dev *ntb)
{
if (!ntb->ops->spad_is_unsafe)
return 0;
return ntb->ops->spad_is_unsafe(ntb);
}
/**
* ntb_spad_count() - get the number of scratchpads
* @ntb: NTB device context.
*
* Hardware and topology may support a different number of scratchpads.
*
* Return: the number of scratchpads.
*/
static inline int ntb_spad_count(struct ntb_dev *ntb)
{
return ntb->ops->spad_count(ntb);
}
/**
* ntb_spad_read() - read the local scratchpad register
* @ntb: NTB device context.
* @idx: Scratchpad index.
*
* Read the local scratchpad register, and return the value.
*
* Return: The value of the local scratchpad register.
*/
static inline u32 ntb_spad_read(struct ntb_dev *ntb, int idx)
{
return ntb->ops->spad_read(ntb, idx);
}
/**
* ntb_spad_write() - write the local scratchpad register
* @ntb: NTB device context.
* @idx: Scratchpad index.
* @val: Scratchpad value.
*
* Write the value to the local scratchpad register.
*
* Return: Zero on success, otherwise an error number.
*/
static inline int ntb_spad_write(struct ntb_dev *ntb, int idx, u32 val)
{
return ntb->ops->spad_write(ntb, idx, val);
}
/**
* ntb_peer_spad_addr() - address of the peer scratchpad register
* @ntb: NTB device context.
* @idx: Scratchpad index.
* @spad_addr: OUT - The address of the peer scratchpad 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.
*
* Return: Zero on success, otherwise an error number.
*/
static inline int ntb_peer_spad_addr(struct ntb_dev *ntb, int idx,
phys_addr_t *spad_addr)
{
if (!ntb->ops->peer_spad_addr)
return -EINVAL;
return ntb->ops->peer_spad_addr(ntb, idx, spad_addr);
}
/**
* ntb_peer_spad_read() - read the peer scratchpad register
* @ntb: NTB device context.
* @idx: Scratchpad index.
*
* Read the peer scratchpad register, and return the value.
*
* Return: The value of the local scratchpad register.
*/
static inline u32 ntb_peer_spad_read(struct ntb_dev *ntb, int idx)
{
if (!ntb->ops->peer_spad_read)
return 0;
return ntb->ops->peer_spad_read(ntb, idx);
}
/**
* ntb_peer_spad_write() - write the peer scratchpad register
* @ntb: NTB device context.
* @idx: Scratchpad index.
* @val: Scratchpad value.
*
* Write the value to the peer scratchpad register.
*
* Return: Zero on success, otherwise an error number.
*/
static inline int ntb_peer_spad_write(struct ntb_dev *ntb, int idx, u32 val)
{
return ntb->ops->peer_spad_write(ntb, idx, val);
}
#endif
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