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-rw-r--r--drivers/firmware/arm_scmi/common.h337
1 files changed, 337 insertions, 0 deletions
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
new file mode 100644
index 0000000000..00b165d1f5
--- /dev/null
+++ b/drivers/firmware/arm_scmi/common.h
@@ -0,0 +1,337 @@
+/* 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 SCMI_MAX_CHANNELS 256
+
+#define SCMI_MAX_RESPONSE_TIMEOUT (2 * MSEC_PER_SEC)
+
+enum scmi_error_codes {
+ SCMI_SUCCESS = 0, /* Success */
+ SCMI_ERR_SUPPORT = -1, /* Not supported */
+ SCMI_ERR_PARAMS = -2, /* Invalid Parameters */
+ SCMI_ERR_ACCESS = -3, /* Invalid access/permission denied */
+ SCMI_ERR_ENTRY = -4, /* Not found */
+ SCMI_ERR_RANGE = -5, /* Value out of range */
+ SCMI_ERR_BUSY = -6, /* Device busy */
+ SCMI_ERR_COMMS = -7, /* Communication Error */
+ SCMI_ERR_GENERIC = -8, /* Generic Error */
+ SCMI_ERR_HARDWARE = -9, /* Hardware Error */
+ SCMI_ERR_PROTOCOL = -10,/* Protocol Error */
+};
+
+static const int scmi_linux_errmap[] = {
+ /* better than switch case as long as return value is continuous */
+ 0, /* SCMI_SUCCESS */
+ -EOPNOTSUPP, /* SCMI_ERR_SUPPORT */
+ -EINVAL, /* SCMI_ERR_PARAM */
+ -EACCES, /* SCMI_ERR_ACCESS */
+ -ENOENT, /* SCMI_ERR_ENTRY */
+ -ERANGE, /* SCMI_ERR_RANGE */
+ -EBUSY, /* SCMI_ERR_BUSY */
+ -ECOMM, /* SCMI_ERR_COMMS */
+ -EIO, /* SCMI_ERR_GENERIC */
+ -EREMOTEIO, /* SCMI_ERR_HARDWARE */
+ -EPROTO, /* SCMI_ERR_PROTOCOL */
+};
+
+static inline int scmi_to_linux_errno(int errno)
+{
+ int err_idx = -errno;
+
+ if (err_idx >= SCMI_SUCCESS && err_idx < ARRAY_SIZE(scmi_linux_errmap))
+ return scmi_linux_errmap[err_idx];
+ return -EIO;
+}
+
+#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);
+void scmi_setup_protocol_implemented(const struct scmi_protocol_handle *ph,
+ u8 *prot_imp);
+
+extern struct bus_type scmi_bus_type;
+
+#define SCMI_BUS_NOTIFY_DEVICE_REQUEST 0
+#define SCMI_BUS_NOTIFY_DEVICE_UNREQUEST 1
+extern struct blocking_notifier_head scmi_requested_devices_nh;
+
+struct scmi_device *scmi_device_create(struct device_node *np,
+ struct device *parent, int protocol,
+ const char *name);
+void scmi_device_destroy(struct device *parent, int protocol, const char *name);
+
+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
+ *
+ * @id: An identifier for this channel: this matches the protocol number
+ * used to initialize this channel
+ * @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 {
+ int id;
+ 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_node *of_node, 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);
+};
+
+/**
+ * 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;
+};
+
+static inline bool is_polling_required(struct scmi_chan_info *cinfo,
+ const struct scmi_desc *desc)
+{
+ return cinfo->no_completion_irq || desc->force_polling;
+}
+
+static inline bool is_transport_polling_capable(const struct scmi_desc *desc)
+{
+ return desc->ops->poll_done || desc->sync_cmds_completed_on_ret;
+}
+
+static inline bool is_polling_enabled(struct scmi_chan_info *cinfo,
+ const struct scmi_desc *desc)
+{
+ return is_polling_required(cinfo, desc) &&
+ is_transport_polling_capable(desc);
+}
+
+void scmi_xfer_raw_put(const struct scmi_handle *handle,
+ struct scmi_xfer *xfer);
+struct scmi_xfer *scmi_xfer_raw_get(const struct scmi_handle *handle);
+struct scmi_chan_info *
+scmi_xfer_raw_channel_get(const struct scmi_handle *handle, u8 protocol_id);
+
+int scmi_xfer_raw_inflight_register(const struct scmi_handle *handle,
+ struct scmi_xfer *xfer);
+
+int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo,
+ struct scmi_xfer *xfer,
+ unsigned int timeout_ms);
+#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);
+
+/* 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 */