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Diffstat (limited to 'include/linux/ntb.h')
| -rw-r--r-- | include/linux/ntb.h | 970 |
1 files changed, 933 insertions, 37 deletions
diff --git a/include/linux/ntb.h b/include/linux/ntb.h index 9ac1a62fc6f5..b02f72bb8e32 100644 --- a/include/linux/ntb.h +++ b/include/linux/ntb.h @@ -4,15 +4,20 @@ * * GPL LICENSE SUMMARY * - * Copyright(c) 2012 Intel Corporation. All rights reserved. + * 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) 2012 Intel Corporation. All rights reserved. + * 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 @@ -40,49 +45,940 @@ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * - * Intel PCIe NTB Linux driver + * PCIe NTB Linux driver * * Contact Information: - * Jon Mason <jon.mason@intel.com> + * Allen Hubbe <Allen.Hubbe@emc.com> */ -struct ntb_transport_qp; +#ifndef _NTB_H_ +#define _NTB_H_ -struct ntb_client { - struct device_driver driver; - int (*probe)(struct pci_dev *pdev); - void (*remove)(struct pci_dev *pdev); +#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); }; -enum { - NTB_LINK_DOWN = 0, - NTB_LINK_UP, +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; }; -int ntb_register_client(struct ntb_client *drvr); -void ntb_unregister_client(struct ntb_client *drvr); -int ntb_register_client_dev(char *device_name); -void ntb_unregister_client_dev(char *device_name); - -struct ntb_queue_handlers { - void (*rx_handler)(struct ntb_transport_qp *qp, void *qp_data, - void *data, int len); - void (*tx_handler)(struct ntb_transport_qp *qp, void *qp_data, - void *data, int len); - void (*event_handler)(void *data, int status); +#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; }; -unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp); -unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp); -struct ntb_transport_qp * -ntb_transport_create_queue(void *data, struct pci_dev *pdev, - const struct ntb_queue_handlers *handlers); -void ntb_transport_free_queue(struct ntb_transport_qp *qp); -int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, - unsigned int len); -int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, - unsigned int len); -void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len); -void ntb_transport_link_up(struct ntb_transport_qp *qp); -void ntb_transport_link_down(struct ntb_transport_qp *qp); -bool ntb_transport_link_query(struct ntb_transport_qp *qp); +#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) +{ + 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 local 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_mw_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) +{ + 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) +{ + 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 |