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Diffstat (limited to 'include/linux/mhi_ep.h')
-rw-r--r-- | include/linux/mhi_ep.h | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/include/linux/mhi_ep.h b/include/linux/mhi_ep.h new file mode 100644 index 000000000000..478aece17046 --- /dev/null +++ b/include/linux/mhi_ep.h @@ -0,0 +1,277 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2022, Linaro Ltd. + * + */ +#ifndef _MHI_EP_H_ +#define _MHI_EP_H_ + +#include <linux/dma-direction.h> +#include <linux/mhi.h> + +#define MHI_EP_DEFAULT_MTU 0x8000 + +/** + * struct mhi_ep_channel_config - Channel configuration structure for controller + * @name: The name of this channel + * @num: The number assigned to this channel + * @num_elements: The number of elements that can be queued to this channel + * @dir: Direction that data may flow on this channel + */ +struct mhi_ep_channel_config { + char *name; + u32 num; + u32 num_elements; + enum dma_data_direction dir; +}; + +/** + * struct mhi_ep_cntrl_config - MHI Endpoint controller configuration + * @mhi_version: MHI spec version supported by the controller + * @max_channels: Maximum number of channels supported + * @num_channels: Number of channels defined in @ch_cfg + * @ch_cfg: Array of defined channels + */ +struct mhi_ep_cntrl_config { + u32 mhi_version; + u32 max_channels; + u32 num_channels; + const struct mhi_ep_channel_config *ch_cfg; +}; + +/** + * struct mhi_ep_db_info - MHI Endpoint doorbell info + * @mask: Mask of the doorbell interrupt + * @status: Status of the doorbell interrupt + */ +struct mhi_ep_db_info { + u32 mask; + u32 status; +}; + +/** + * struct mhi_ep_cntrl - MHI Endpoint controller structure + * @cntrl_dev: Pointer to the struct device of physical bus acting as the MHI + * Endpoint controller + * @mhi_dev: MHI Endpoint device instance for the controller + * @mmio: MMIO region containing the MHI registers + * @mhi_chan: Points to the channel configuration table + * @mhi_event: Points to the event ring configurations table + * @mhi_cmd: Points to the command ring configurations table + * @sm: MHI Endpoint state machine + * @ch_ctx_cache: Cache of host channel context data structure + * @ev_ctx_cache: Cache of host event context data structure + * @cmd_ctx_cache: Cache of host command context data structure + * @ch_ctx_host_pa: Physical address of host channel context data structure + * @ev_ctx_host_pa: Physical address of host event context data structure + * @cmd_ctx_host_pa: Physical address of host command context data structure + * @ch_ctx_cache_phys: Physical address of the host channel context cache + * @ev_ctx_cache_phys: Physical address of the host event context cache + * @cmd_ctx_cache_phys: Physical address of the host command context cache + * @chdb: Array of channel doorbell interrupt info + * @event_lock: Lock for protecting event rings + * @list_lock: Lock for protecting state transition and channel doorbell lists + * @state_lock: Lock for protecting state transitions + * @st_transition_list: List of state transitions + * @ch_db_list: List of queued channel doorbells + * @wq: Dedicated workqueue for handling rings and state changes + * @state_work: State transition worker + * @reset_work: Worker for MHI Endpoint reset + * @cmd_ring_work: Worker for processing command rings + * @ch_ring_work: Worker for processing channel rings + * @raise_irq: CB function for raising IRQ to the host + * @alloc_map: CB function for allocating memory in endpoint for storing host context and mapping it + * @unmap_free: CB function to unmap and free the allocated memory in endpoint for storing host context + * @read_from_host: CB function for reading from host memory from endpoint + * @write_to_host: CB function for writing to host memory from endpoint + * @mhi_state: MHI Endpoint state + * @max_chan: Maximum channels supported by the endpoint controller + * @mru: MRU (Maximum Receive Unit) value of the endpoint controller + * @event_rings: Number of event rings supported by the endpoint controller + * @hw_event_rings: Number of hardware event rings supported by the endpoint controller + * @chdb_offset: Channel doorbell offset set by the host + * @erdb_offset: Event ring doorbell offset set by the host + * @index: MHI Endpoint controller index + * @irq: IRQ used by the endpoint controller + * @enabled: Check if the endpoint controller is enabled or not + */ +struct mhi_ep_cntrl { + struct device *cntrl_dev; + struct mhi_ep_device *mhi_dev; + void __iomem *mmio; + + struct mhi_ep_chan *mhi_chan; + struct mhi_ep_event *mhi_event; + struct mhi_ep_cmd *mhi_cmd; + struct mhi_ep_sm *sm; + + struct mhi_chan_ctxt *ch_ctx_cache; + struct mhi_event_ctxt *ev_ctx_cache; + struct mhi_cmd_ctxt *cmd_ctx_cache; + u64 ch_ctx_host_pa; + u64 ev_ctx_host_pa; + u64 cmd_ctx_host_pa; + phys_addr_t ch_ctx_cache_phys; + phys_addr_t ev_ctx_cache_phys; + phys_addr_t cmd_ctx_cache_phys; + + struct mhi_ep_db_info chdb[4]; + struct mutex event_lock; + spinlock_t list_lock; + spinlock_t state_lock; + + struct list_head st_transition_list; + struct list_head ch_db_list; + + struct workqueue_struct *wq; + struct work_struct state_work; + struct work_struct reset_work; + struct work_struct cmd_ring_work; + struct work_struct ch_ring_work; + + void (*raise_irq)(struct mhi_ep_cntrl *mhi_cntrl, u32 vector); + int (*alloc_map)(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, phys_addr_t *phys_ptr, + void __iomem **virt, size_t size); + void (*unmap_free)(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, phys_addr_t phys, + void __iomem *virt, size_t size); + int (*read_from_host)(struct mhi_ep_cntrl *mhi_cntrl, u64 from, void *to, size_t size); + int (*write_to_host)(struct mhi_ep_cntrl *mhi_cntrl, void *from, u64 to, size_t size); + + enum mhi_state mhi_state; + + u32 max_chan; + u32 mru; + u32 event_rings; + u32 hw_event_rings; + u32 chdb_offset; + u32 erdb_offset; + u32 index; + int irq; + bool enabled; +}; + +/** + * struct mhi_ep_device - Structure representing an MHI Endpoint device that binds + * to channels or is associated with controllers + * @dev: Driver model device node for the MHI Endpoint device + * @mhi_cntrl: Controller the device belongs to + * @id: Pointer to MHI Endpoint device ID struct + * @name: Name of the associated MHI Endpoint device + * @ul_chan: UL (from host to endpoint) channel for the device + * @dl_chan: DL (from endpoint to host) channel for the device + * @dev_type: MHI device type + */ +struct mhi_ep_device { + struct device dev; + struct mhi_ep_cntrl *mhi_cntrl; + const struct mhi_device_id *id; + const char *name; + struct mhi_ep_chan *ul_chan; + struct mhi_ep_chan *dl_chan; + enum mhi_device_type dev_type; +}; + +/** + * struct mhi_ep_driver - Structure representing a MHI Endpoint client driver + * @id_table: Pointer to MHI Endpoint device ID table + * @driver: Device driver model driver + * @probe: CB function for client driver probe function + * @remove: CB function for client driver remove function + * @ul_xfer_cb: CB function for UL (from host to endpoint) data transfer + * @dl_xfer_cb: CB function for DL (from endpoint to host) data transfer + */ +struct mhi_ep_driver { + const struct mhi_device_id *id_table; + struct device_driver driver; + int (*probe)(struct mhi_ep_device *mhi_ep, + const struct mhi_device_id *id); + void (*remove)(struct mhi_ep_device *mhi_ep); + void (*ul_xfer_cb)(struct mhi_ep_device *mhi_dev, + struct mhi_result *result); + void (*dl_xfer_cb)(struct mhi_ep_device *mhi_dev, + struct mhi_result *result); +}; + +#define to_mhi_ep_device(dev) container_of(dev, struct mhi_ep_device, dev) +#define to_mhi_ep_driver(drv) container_of(drv, struct mhi_ep_driver, driver) + +/* + * module_mhi_ep_driver() - Helper macro for drivers that don't do + * anything special other than using default mhi_ep_driver_register() and + * mhi_ep_driver_unregister(). This eliminates a lot of boilerplate. + * Each module may only use this macro once. + */ +#define module_mhi_ep_driver(mhi_drv) \ + module_driver(mhi_drv, mhi_ep_driver_register, \ + mhi_ep_driver_unregister) + +/* + * Macro to avoid include chaining to get THIS_MODULE + */ +#define mhi_ep_driver_register(mhi_drv) \ + __mhi_ep_driver_register(mhi_drv, THIS_MODULE) + +/** + * __mhi_ep_driver_register - Register a driver with MHI Endpoint bus + * @mhi_drv: Driver to be associated with the device + * @owner: The module owner + * + * Return: 0 if driver registrations succeeds, a negative error code otherwise. + */ +int __mhi_ep_driver_register(struct mhi_ep_driver *mhi_drv, struct module *owner); + +/** + * mhi_ep_driver_unregister - Unregister a driver from MHI Endpoint bus + * @mhi_drv: Driver associated with the device + */ +void mhi_ep_driver_unregister(struct mhi_ep_driver *mhi_drv); + +/** + * mhi_ep_register_controller - Register MHI Endpoint controller + * @mhi_cntrl: MHI Endpoint controller to register + * @config: Configuration to use for the controller + * + * Return: 0 if controller registrations succeeds, a negative error code otherwise. + */ +int mhi_ep_register_controller(struct mhi_ep_cntrl *mhi_cntrl, + const struct mhi_ep_cntrl_config *config); + +/** + * mhi_ep_unregister_controller - Unregister MHI Endpoint controller + * @mhi_cntrl: MHI Endpoint controller to unregister + */ +void mhi_ep_unregister_controller(struct mhi_ep_cntrl *mhi_cntrl); + +/** + * mhi_ep_power_up - Power up the MHI endpoint stack + * @mhi_cntrl: MHI Endpoint controller + * + * Return: 0 if power up succeeds, a negative error code otherwise. + */ +int mhi_ep_power_up(struct mhi_ep_cntrl *mhi_cntrl); + +/** + * mhi_ep_power_down - Power down the MHI endpoint stack + * @mhi_cntrl: MHI controller + */ +void mhi_ep_power_down(struct mhi_ep_cntrl *mhi_cntrl); + +/** + * mhi_ep_queue_is_empty - Determine whether the transfer queue is empty + * @mhi_dev: Device associated with the channels + * @dir: DMA direction for the channel + * + * Return: true if the queue is empty, false otherwise. + */ +bool mhi_ep_queue_is_empty(struct mhi_ep_device *mhi_dev, enum dma_data_direction dir); + +/** + * mhi_ep_queue_skb - Send SKBs to host over MHI Endpoint + * @mhi_dev: Device associated with the DL channel + * @skb: SKBs to be queued + * + * Return: 0 if the SKBs has been sent successfully, a negative error code otherwise. + */ +int mhi_ep_queue_skb(struct mhi_ep_device *mhi_dev, struct sk_buff *skb); + +#endif |