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/* 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 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/scmi_protocol.h>
#include <linux/types.h>
#include <asm/unaligned.h>
#define PROTOCOL_REV_MINOR_MASK GENMASK(15, 0)
#define PROTOCOL_REV_MAJOR_MASK GENMASK(31, 16)
#define PROTOCOL_REV_MAJOR(x) (u16)(FIELD_GET(PROTOCOL_REV_MAJOR_MASK, (x)))
#define PROTOCOL_REV_MINOR(x) (u16)(FIELD_GET(PROTOCOL_REV_MINOR_MASK, (x)))
#define MAX_PROTOCOLS_IMP 16
#define MAX_OPPS 16
enum scmi_common_cmd {
PROTOCOL_VERSION = 0x0,
PROTOCOL_ATTRIBUTES = 0x1,
PROTOCOL_MESSAGE_ATTRIBUTES = 0x2,
};
/**
* struct scmi_msg_resp_prot_version - Response for a message
*
* @minor_version: Minor version of the ABI that firmware supports
* @major_version: Major version of the ABI that firmware supports
*
* In general, ABI version changes follow the rule that minor version increments
* are backward compatible. Major revision changes in ABI may not be
* backward compatible.
*
* Response to a generic message with message type SCMI_MSG_VERSION
*/
struct scmi_msg_resp_prot_version {
__le16 minor_version;
__le16 major_version;
};
#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)
/**
* struct scmi_msg_hdr - Message(Tx/Rx) header
*
* @id: The identifier of the message being sent
* @protocol_id: The identifier of the protocol used to send @id message
* @seq: The token to identify the message. When a message returns, the
* platform returns the whole message header unmodified including the
* token
* @status: Status of the transfer once it's complete
* @poll_completion: Indicate if the transfer needs to be polled for
* completion or interrupt mode is used
*/
struct scmi_msg_hdr {
u8 id;
u8 protocol_id;
u16 seq;
u32 status;
bool poll_completion;
};
/**
* pack_scmi_header() - packs and returns 32-bit header
*
* @hdr: pointer to header containing all the information on message id,
* protocol id and sequence id.
*
* 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_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);
}
/**
* struct scmi_msg - Message(Tx/Rx) structure
*
* @buf: Buffer pointer
* @len: Length of data in the Buffer
*/
struct scmi_msg {
void *buf;
size_t len;
};
/**
* struct scmi_xfer - Structure representing a message flow
*
* @transfer_id: Unique ID for debug & profiling purpose
* @hdr: Transmit message header
* @tx: Transmit message
* @rx: Receive message, the buffer should be pre-allocated to store
* message. If request-ACK protocol is used, we can reuse the same
* buffer for the rx path as we use for the tx path.
* @done: command message transmit completion event
* @async_done: pointer to delayed response message received event completion
*/
struct scmi_xfer {
int transfer_id;
struct scmi_msg_hdr hdr;
struct scmi_msg tx;
struct scmi_msg rx;
struct completion done;
struct completion *async_done;
};
void scmi_xfer_put(const struct scmi_handle *h, struct scmi_xfer *xfer);
int scmi_do_xfer(const struct scmi_handle *h, struct scmi_xfer *xfer);
int scmi_do_xfer_with_response(const struct scmi_handle *h,
struct scmi_xfer *xfer);
int scmi_xfer_get_init(const struct scmi_handle *h, u8 msg_id, u8 prot_id,
size_t tx_size, size_t rx_size, struct scmi_xfer **p);
int scmi_handle_put(const struct scmi_handle *handle);
struct scmi_handle *scmi_handle_get(struct device *dev);
void scmi_set_handle(struct scmi_device *scmi_dev);
int scmi_version_get(const struct scmi_handle *h, u8 protocol, u32 *version);
void scmi_setup_protocol_implemented(const struct scmi_handle *handle,
u8 *prot_imp);
int scmi_base_protocol_init(struct scmi_handle *h);
/* SCMI Transport */
/**
* struct scmi_chan_info - Structure representing a SCMI channel information
*
* @dev: Reference to device in the SCMI hierarchy corresponding to this
* channel
* @handle: Pointer to SCMI entity handle
* @transport_info: Transport layer related information
*/
struct scmi_chan_info {
struct device *dev;
struct scmi_handle *handle;
void *transport_info;
};
/**
* struct scmi_transport_ops - Structure representing a SCMI transport ops
*
* @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
* @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 {
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);
int (*send_message)(struct scmi_chan_info *cinfo,
struct scmi_xfer *xfer);
void (*mark_txdone)(struct scmi_chan_info *cinfo, int ret);
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);
};
/**
* struct scmi_desc - Description of SoC integration
*
* @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 that can be pending
* simultaneously in the system
* @max_msg_size: Maximum size of data per message that can be handled.
*/
struct scmi_desc {
struct scmi_transport_ops *ops;
int max_rx_timeout_ms;
int max_msg;
int max_msg_size;
};
extern const struct scmi_desc scmi_mailbox_desc;
#ifdef CONFIG_HAVE_ARM_SMCCC
extern const struct scmi_desc scmi_smc_desc;
#endif
void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr);
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);
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);
#endif /* _SCMI_COMMON_H */