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Diffstat (limited to 'drivers/firmware/arm_scmi/common.h')
| -rw-r--r-- | drivers/firmware/arm_scmi/common.h | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h new file mode 100644 index 000000000..4ac72754c --- /dev/null +++ b/drivers/firmware/arm_scmi/common.h @@ -0,0 +1,267 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * System Control and Management Interface (SCMI) Message Protocol + * driver common header file containing some definitions, structures + * and function prototypes used in all the different SCMI protocols. + * + * Copyright (C) 2018-2022 ARM Ltd. + */ +#ifndef _SCMI_COMMON_H +#define _SCMI_COMMON_H + +#include <linux/bitfield.h> +#include <linux/completion.h> +#include <linux/device.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/hashtable.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/refcount.h> +#include <linux/scmi_protocol.h> +#include <linux/spinlock.h> +#include <linux/types.h> + +#include <asm/unaligned.h> + +#include "protocols.h" +#include "notify.h" + +#define MSG_ID_MASK GENMASK(7, 0) +#define MSG_XTRACT_ID(hdr) FIELD_GET(MSG_ID_MASK, (hdr)) +#define MSG_TYPE_MASK GENMASK(9, 8) +#define MSG_XTRACT_TYPE(hdr) FIELD_GET(MSG_TYPE_MASK, (hdr)) +#define MSG_TYPE_COMMAND 0 +#define MSG_TYPE_DELAYED_RESP 2 +#define MSG_TYPE_NOTIFICATION 3 +#define MSG_PROTOCOL_ID_MASK GENMASK(17, 10) +#define MSG_XTRACT_PROT_ID(hdr) FIELD_GET(MSG_PROTOCOL_ID_MASK, (hdr)) +#define MSG_TOKEN_ID_MASK GENMASK(27, 18) +#define MSG_XTRACT_TOKEN(hdr) FIELD_GET(MSG_TOKEN_ID_MASK, (hdr)) +#define MSG_TOKEN_MAX (MSG_XTRACT_TOKEN(MSG_TOKEN_ID_MASK) + 1) + +/* + * Size of @pending_xfers hashtable included in @scmi_xfers_info; ideally, in + * order to minimize space and collisions, this should equal max_msg, i.e. the + * maximum number of in-flight messages on a specific platform, but such value + * is only available at runtime while kernel hashtables are statically sized: + * pick instead as a fixed static size the maximum number of entries that can + * fit the whole table into one 4k page. + */ +#define SCMI_PENDING_XFERS_HT_ORDER_SZ 9 + +/** + * pack_scmi_header() - packs and returns 32-bit header + * + * @hdr: pointer to header containing all the information on message id, + * protocol id, sequence id and type. + * + * Return: 32-bit packed message header to be sent to the platform. + */ +static inline u32 pack_scmi_header(struct scmi_msg_hdr *hdr) +{ + return FIELD_PREP(MSG_ID_MASK, hdr->id) | + FIELD_PREP(MSG_TYPE_MASK, hdr->type) | + FIELD_PREP(MSG_TOKEN_ID_MASK, hdr->seq) | + FIELD_PREP(MSG_PROTOCOL_ID_MASK, hdr->protocol_id); +} + +/** + * unpack_scmi_header() - unpacks and records message and protocol id + * + * @msg_hdr: 32-bit packed message header sent from the platform + * @hdr: pointer to header to fetch message and protocol id. + */ +static inline void unpack_scmi_header(u32 msg_hdr, struct scmi_msg_hdr *hdr) +{ + hdr->id = MSG_XTRACT_ID(msg_hdr); + hdr->protocol_id = MSG_XTRACT_PROT_ID(msg_hdr); + hdr->type = MSG_XTRACT_TYPE(msg_hdr); +} + +/* + * An helper macro to lookup an xfer from the @pending_xfers hashtable + * using the message sequence number token as a key. + */ +#define XFER_FIND(__ht, __k) \ +({ \ + typeof(__k) k_ = __k; \ + struct scmi_xfer *xfer_ = NULL; \ + \ + hash_for_each_possible((__ht), xfer_, node, k_) \ + if (xfer_->hdr.seq == k_) \ + break; \ + xfer_; \ +}) + +struct scmi_revision_info * +scmi_revision_area_get(const struct scmi_protocol_handle *ph); +int scmi_handle_put(const struct scmi_handle *handle); +void scmi_device_link_add(struct device *consumer, struct device *supplier); +struct scmi_handle *scmi_handle_get(struct device *dev); +void scmi_set_handle(struct scmi_device *scmi_dev); +void scmi_setup_protocol_implemented(const struct scmi_protocol_handle *ph, + u8 *prot_imp); + +int __init scmi_bus_init(void); +void __exit scmi_bus_exit(void); + +const struct scmi_protocol *scmi_protocol_get(int protocol_id); +void scmi_protocol_put(int protocol_id); + +int scmi_protocol_acquire(const struct scmi_handle *handle, u8 protocol_id); +void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id); + +/* SCMI Transport */ +/** + * struct scmi_chan_info - Structure representing a SCMI channel information + * + * @dev: Reference to device in the SCMI hierarchy corresponding to this + * channel + * @rx_timeout_ms: The configured RX timeout in milliseconds. + * @handle: Pointer to SCMI entity handle + * @no_completion_irq: Flag to indicate that this channel has no completion + * interrupt mechanism for synchronous commands. + * This can be dynamically set by transports at run-time + * inside their provided .chan_setup(). + * @transport_info: Transport layer related information + */ +struct scmi_chan_info { + struct device *dev; + unsigned int rx_timeout_ms; + struct scmi_handle *handle; + bool no_completion_irq; + void *transport_info; +}; + +/** + * struct scmi_transport_ops - Structure representing a SCMI transport ops + * + * @link_supplier: Optional callback to add link to a supplier device + * @chan_available: Callback to check if channel is available or not + * @chan_setup: Callback to allocate and setup a channel + * @chan_free: Callback to free a channel + * @get_max_msg: Optional callback to provide max_msg dynamically + * Returns the maximum number of messages for the channel type + * (tx or rx) that can be pending simultaneously in the system + * @send_message: Callback to send a message + * @mark_txdone: Callback to mark tx as done + * @fetch_response: Callback to fetch response + * @fetch_notification: Callback to fetch notification + * @clear_channel: Callback to clear a channel + * @poll_done: Callback to poll transfer status + */ +struct scmi_transport_ops { + int (*link_supplier)(struct device *dev); + bool (*chan_available)(struct device *dev, int idx); + int (*chan_setup)(struct scmi_chan_info *cinfo, struct device *dev, + bool tx); + int (*chan_free)(int id, void *p, void *data); + unsigned int (*get_max_msg)(struct scmi_chan_info *base_cinfo); + int (*send_message)(struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer); + void (*mark_txdone)(struct scmi_chan_info *cinfo, int ret, + struct scmi_xfer *xfer); + void (*fetch_response)(struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer); + void (*fetch_notification)(struct scmi_chan_info *cinfo, + size_t max_len, struct scmi_xfer *xfer); + void (*clear_channel)(struct scmi_chan_info *cinfo); + bool (*poll_done)(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer); +}; + +int scmi_protocol_device_request(const struct scmi_device_id *id_table); +void scmi_protocol_device_unrequest(const struct scmi_device_id *id_table); +struct scmi_device *scmi_child_dev_find(struct device *parent, + int prot_id, const char *name); + +/** + * struct scmi_desc - Description of SoC integration + * + * @transport_init: An optional function that a transport can provide to + * initialize some transport-specific setup during SCMI core + * initialization, so ahead of SCMI core probing. + * @transport_exit: An optional function that a transport can provide to + * de-initialize some transport-specific setup during SCMI core + * de-initialization, so after SCMI core removal. + * @ops: Pointer to the transport specific ops structure + * @max_rx_timeout_ms: Timeout for communication with SoC (in Milliseconds) + * @max_msg: Maximum number of messages for a channel type (tx or rx) that can + * be pending simultaneously in the system. May be overridden by the + * get_max_msg op. + * @max_msg_size: Maximum size of data per message that can be handled. + * @force_polling: Flag to force this whole transport to use SCMI core polling + * mechanism instead of completion interrupts even if available. + * @sync_cmds_completed_on_ret: Flag to indicate that the transport assures + * synchronous-command messages are atomically + * completed on .send_message: no need to poll + * actively waiting for a response. + * Used by core internally only when polling is + * selected as a waiting for reply method: i.e. + * if a completion irq was found use that anyway. + * @atomic_enabled: Flag to indicate that this transport, which is assured not + * to sleep anywhere on the TX path, can be used in atomic mode + * when requested. + */ +struct scmi_desc { + int (*transport_init)(void); + void (*transport_exit)(void); + const struct scmi_transport_ops *ops; + int max_rx_timeout_ms; + int max_msg; + int max_msg_size; + const bool force_polling; + const bool sync_cmds_completed_on_ret; + const bool atomic_enabled; +}; + +#ifdef CONFIG_ARM_SCMI_TRANSPORT_MAILBOX +extern const struct scmi_desc scmi_mailbox_desc; +#endif +#ifdef CONFIG_ARM_SCMI_TRANSPORT_SMC +extern const struct scmi_desc scmi_smc_desc; +#endif +#ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO +extern const struct scmi_desc scmi_virtio_desc; +#endif +#ifdef CONFIG_ARM_SCMI_TRANSPORT_OPTEE +extern const struct scmi_desc scmi_optee_desc; +#endif + +void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv); +void scmi_free_channel(struct scmi_chan_info *cinfo, struct idr *idr, int id); + +/* shmem related declarations */ +struct scmi_shared_mem; + +void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem, + struct scmi_xfer *xfer, struct scmi_chan_info *cinfo); +u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem); +void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem, + struct scmi_xfer *xfer); +void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem, + size_t max_len, struct scmi_xfer *xfer); +void shmem_clear_channel(struct scmi_shared_mem __iomem *shmem); +bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem, + struct scmi_xfer *xfer); +bool shmem_channel_free(struct scmi_shared_mem __iomem *shmem); + +/* declarations for message passing transports */ +struct scmi_msg_payld; + +/* Maximum overhead of message w.r.t. struct scmi_desc.max_msg_size */ +#define SCMI_MSG_MAX_PROT_OVERHEAD (2 * sizeof(__le32)) + +size_t msg_response_size(struct scmi_xfer *xfer); +size_t msg_command_size(struct scmi_xfer *xfer); +void msg_tx_prepare(struct scmi_msg_payld *msg, struct scmi_xfer *xfer); +u32 msg_read_header(struct scmi_msg_payld *msg); +void msg_fetch_response(struct scmi_msg_payld *msg, size_t len, + struct scmi_xfer *xfer); +void msg_fetch_notification(struct scmi_msg_payld *msg, size_t len, + size_t max_len, struct scmi_xfer *xfer); + +void scmi_notification_instance_data_set(const struct scmi_handle *handle, + void *priv); +void *scmi_notification_instance_data_get(const struct scmi_handle *handle); +#endif /* _SCMI_COMMON_H */ |