Initial import

1 files changed, 947 insertions, 0 deletions

diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c
new file mode 100644
index 000000000..58da92565
--- /dev/null
+++ b/drivers/misc/mei/hbm.c
@@ -0,0 +1,947 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2003-2012, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ */
+
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "hbm.h"
+#include "client.h"
+
+static const char *mei_hbm_status_str(enum mei_hbm_status status)
+{
+#define MEI_HBM_STATUS(status) case MEI_HBMS_##status: return #status
+	switch (status) {
+	MEI_HBM_STATUS(SUCCESS);
+	MEI_HBM_STATUS(CLIENT_NOT_FOUND);
+	MEI_HBM_STATUS(ALREADY_EXISTS);
+	MEI_HBM_STATUS(REJECTED);
+	MEI_HBM_STATUS(INVALID_PARAMETER);
+	MEI_HBM_STATUS(NOT_ALLOWED);
+	MEI_HBM_STATUS(ALREADY_STARTED);
+	MEI_HBM_STATUS(NOT_STARTED);
+	default: return "unknown";
+	}
+#undef MEI_HBM_STATUS
+};
+
+static const char *mei_cl_conn_status_str(enum mei_cl_connect_status status)
+{
+#define MEI_CL_CS(status) case MEI_CL_CONN_##status: return #status
+	switch (status) {
+	MEI_CL_CS(SUCCESS);
+	MEI_CL_CS(NOT_FOUND);
+	MEI_CL_CS(ALREADY_STARTED);
+	MEI_CL_CS(OUT_OF_RESOURCES);
+	MEI_CL_CS(MESSAGE_SMALL);
+	default: return "unknown";
+	}
+#undef MEI_CL_CCS
+}
+
+const char *mei_hbm_state_str(enum mei_hbm_state state)
+{
+#define MEI_HBM_STATE(state) case MEI_HBM_##state: return #state
+	switch (state) {
+	MEI_HBM_STATE(IDLE);
+	MEI_HBM_STATE(STARTING);
+	MEI_HBM_STATE(STARTED);
+	MEI_HBM_STATE(ENUM_CLIENTS);
+	MEI_HBM_STATE(CLIENT_PROPERTIES);
+	MEI_HBM_STATE(STOPPED);
+	default:
+		return "unknown";
+	}
+#undef MEI_HBM_STATE
+}
+
+/**
+ * mei_cl_conn_status_to_errno - convert client connect response
+ * status to error code
+ *
+ * @status: client connect response status
+ *
+ * Return: corresponding error code
+ */
+static int mei_cl_conn_status_to_errno(enum mei_cl_connect_status status)
+{
+	switch (status) {
+	case MEI_CL_CONN_SUCCESS:          return 0;
+	case MEI_CL_CONN_NOT_FOUND:        return -ENOTTY;
+	case MEI_CL_CONN_ALREADY_STARTED:  return -EBUSY;
+	case MEI_CL_CONN_OUT_OF_RESOURCES: return -EBUSY;
+	case MEI_CL_CONN_MESSAGE_SMALL:    return -EINVAL;
+	default:                           return -EINVAL;
+	}
+}
+
+/**
+ * mei_hbm_idle - set hbm to idle state
+ *
+ * @dev: the device structure
+ */
+void mei_hbm_idle(struct mei_device *dev)
+{
+	dev->init_clients_timer = 0;
+	dev->hbm_state = MEI_HBM_IDLE;
+}
+
+/**
+ * mei_hbm_reset - reset hbm counters and book keeping data structurs
+ *
+ * @dev: the device structure
+ */
+void mei_hbm_reset(struct mei_device *dev)
+{
+	dev->me_client_index = 0;
+
+	mei_me_cl_rm_all(dev);
+
+	mei_hbm_idle(dev);
+}
+
+/**
+ * mei_hbm_hdr - construct hbm header
+ *
+ * @hdr: hbm header
+ * @length: payload length
+ */
+
+static inline void mei_hbm_hdr(struct mei_msg_hdr *hdr, size_t length)
+{
+	hdr->host_addr = 0;
+	hdr->me_addr = 0;
+	hdr->length = length;
+	hdr->msg_complete = 1;
+	hdr->reserved = 0;
+}
+
+/**
+ * mei_hbm_cl_hdr - construct client hbm header
+ *
+ * @cl: client
+ * @hbm_cmd: host bus message command
+ * @buf: buffer for cl header
+ * @len: buffer length
+ */
+static inline
+void mei_hbm_cl_hdr(struct mei_cl *cl, u8 hbm_cmd, void *buf, size_t len)
+{
+	struct mei_hbm_cl_cmd *cmd = buf;
+
+	memset(cmd, 0, len);
+
+	cmd->hbm_cmd = hbm_cmd;
+	cmd->host_addr = cl->host_client_id;
+	cmd->me_addr = cl->me_client_id;
+}
+
+/**
+ * mei_hbm_cl_write - write simple hbm client message
+ *
+ * @dev: the device structure
+ * @cl: client
+ * @hbm_cmd: host bus message command
+ * @len: buffer length
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+static inline
+int mei_hbm_cl_write(struct mei_device *dev,
+		     struct mei_cl *cl, u8 hbm_cmd, size_t len)
+{
+	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
+
+	mei_hbm_hdr(mei_hdr, len);
+	mei_hbm_cl_hdr(cl, hbm_cmd, dev->wr_msg.data, len);
+
+	return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
+}
+
+/**
+ * mei_hbm_cl_addr_equal - check if the client's and
+ *	the message address match
+ *
+ * @cl: client
+ * @cmd: hbm client message
+ *
+ * Return: true if addresses are the same
+ */
+static inline
+bool mei_hbm_cl_addr_equal(struct mei_cl *cl, struct mei_hbm_cl_cmd *cmd)
+{
+	return cl->host_client_id == cmd->host_addr &&
+		cl->me_client_id == cmd->me_addr;
+}
+
+/**
+ * mei_hbm_cl_find_by_cmd - find recipient client
+ *
+ * @dev: the device structure
+ * @buf: a buffer with hbm cl command
+ *
+ * Return: the recipient client or NULL if not found
+ */
+static inline
+struct mei_cl *mei_hbm_cl_find_by_cmd(struct mei_device *dev, void *buf)
+{
+	struct mei_hbm_cl_cmd *cmd = (struct mei_hbm_cl_cmd *)buf;
+	struct mei_cl *cl;
+
+	list_for_each_entry(cl, &dev->file_list, link)
+		if (mei_hbm_cl_addr_equal(cl, cmd))
+			return cl;
+	return NULL;
+}
+
+
+/**
+ * mei_hbm_start_wait - wait for start response message.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+int mei_hbm_start_wait(struct mei_device *dev)
+{
+	int ret;
+
+	if (dev->hbm_state > MEI_HBM_STARTING)
+		return 0;
+
+	mutex_unlock(&dev->device_lock);
+	ret = wait_event_timeout(dev->wait_hbm_start,
+			dev->hbm_state != MEI_HBM_STARTING,
+			mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
+	mutex_lock(&dev->device_lock);
+
+	if (ret == 0 && (dev->hbm_state <= MEI_HBM_STARTING)) {
+		dev->hbm_state = MEI_HBM_IDLE;
+		dev_err(dev->dev, "waiting for mei start failed\n");
+		return -ETIME;
+	}
+	return 0;
+}
+
+/**
+ * mei_hbm_start_req - sends start request message.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+int mei_hbm_start_req(struct mei_device *dev)
+{
+	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
+	struct hbm_host_version_request *start_req;
+	const size_t len = sizeof(struct hbm_host_version_request);
+	int ret;
+
+	mei_hbm_reset(dev);
+
+	mei_hbm_hdr(mei_hdr, len);
+
+	/* host start message */
+	start_req = (struct hbm_host_version_request *)dev->wr_msg.data;
+	memset(start_req, 0, len);
+	start_req->hbm_cmd = HOST_START_REQ_CMD;
+	start_req->host_version.major_version = HBM_MAJOR_VERSION;
+	start_req->host_version.minor_version = HBM_MINOR_VERSION;
+
+	dev->hbm_state = MEI_HBM_IDLE;
+	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
+	if (ret) {
+		dev_err(dev->dev, "version message write failed: ret = %d\n",
+			ret);
+		return ret;
+	}
+
+	dev->hbm_state = MEI_HBM_STARTING;
+	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
+	return 0;
+}
+
+/*
+ * mei_hbm_enum_clients_req - sends enumeration client request message.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_enum_clients_req(struct mei_device *dev)
+{
+	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
+	struct hbm_host_enum_request *enum_req;
+	const size_t len = sizeof(struct hbm_host_enum_request);
+	int ret;
+
+	/* enumerate clients */
+	mei_hbm_hdr(mei_hdr, len);
+
+	enum_req = (struct hbm_host_enum_request *)dev->wr_msg.data;
+	memset(enum_req, 0, len);
+	enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;
+
+	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
+	if (ret) {
+		dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
+			ret);
+		return ret;
+	}
+	dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
+	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
+	return 0;
+}
+
+/*
+ * mei_hbm_me_cl_add - add new me client to the list
+ *
+ * @dev: the device structure
+ * @res: hbm property response
+ *
+ * Return: 0 on success and -ENOMEM on allocation failure
+ */
+
+static int mei_hbm_me_cl_add(struct mei_device *dev,
+			     struct hbm_props_response *res)
+{
+	struct mei_me_client *me_cl;
+	const uuid_le *uuid = &res->client_properties.protocol_name;
+
+	mei_me_cl_rm_by_uuid(dev, uuid);
+
+	me_cl = kzalloc(sizeof(struct mei_me_client), GFP_KERNEL);
+	if (!me_cl)
+		return -ENOMEM;
+
+	mei_me_cl_init(me_cl);
+
+	me_cl->props = res->client_properties;
+	me_cl->client_id = res->me_addr;
+	me_cl->mei_flow_ctrl_creds = 0;
+
+	mei_me_cl_add(dev, me_cl);
+
+	return 0;
+}
+
+/**
+ * mei_hbm_prop_req - request property for a single client
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+
+static int mei_hbm_prop_req(struct mei_device *dev)
+{
+
+	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
+	struct hbm_props_request *prop_req;
+	const size_t len = sizeof(struct hbm_props_request);
+	unsigned long next_client_index;
+	int ret;
+
+	next_client_index = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX,
+					  dev->me_client_index);
+
+	/* We got all client properties */
+	if (next_client_index == MEI_CLIENTS_MAX) {
+		dev->hbm_state = MEI_HBM_STARTED;
+		schedule_work(&dev->init_work);
+
+		return 0;
+	}
+
+	mei_hbm_hdr(mei_hdr, len);
+	prop_req = (struct hbm_props_request *)dev->wr_msg.data;
+
+	memset(prop_req, 0, sizeof(struct hbm_props_request));
+
+	prop_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
+	prop_req->me_addr = next_client_index;
+
+	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
+	if (ret) {
+		dev_err(dev->dev, "properties request write failed: ret = %d\n",
+			ret);
+		return ret;
+	}
+
+	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
+	dev->me_client_index = next_client_index;
+
+	return 0;
+}
+
+/*
+ * mei_hbm_pg - sends pg command
+ *
+ * @dev: the device structure
+ * @pg_cmd: the pg command code
+ *
+ * Return: -EIO on write failure
+ *         -EOPNOTSUPP if the operation is not supported by the protocol
+ */
+int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
+{
+	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
+	struct hbm_power_gate *req;
+	const size_t len = sizeof(struct hbm_power_gate);
+	int ret;
+
+	if (!dev->hbm_f_pg_supported)
+		return -EOPNOTSUPP;
+
+	mei_hbm_hdr(mei_hdr, len);
+
+	req = (struct hbm_power_gate *)dev->wr_msg.data;
+	memset(req, 0, len);
+	req->hbm_cmd = pg_cmd;
+
+	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
+	if (ret)
+		dev_err(dev->dev, "power gate command write failed.\n");
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mei_hbm_pg);
+
+/**
+ * mei_hbm_stop_req - send stop request message
+ *
+ * @dev: mei device
+ *
+ * Return: -EIO on write failure
+ */
+static int mei_hbm_stop_req(struct mei_device *dev)
+{
+	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
+	struct hbm_host_stop_request *req =
+			(struct hbm_host_stop_request *)dev->wr_msg.data;
+	const size_t len = sizeof(struct hbm_host_stop_request);
+
+	mei_hbm_hdr(mei_hdr, len);
+
+	memset(req, 0, len);
+	req->hbm_cmd = HOST_STOP_REQ_CMD;
+	req->reason = DRIVER_STOP_REQUEST;
+
+	return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
+}
+
+/**
+ * mei_hbm_cl_flow_control_req - sends flow control request.
+ *
+ * @dev: the device structure
+ * @cl: client info
+ *
+ * Return: -EIO on write failure
+ */
+int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
+{
+	const size_t len = sizeof(struct hbm_flow_control);
+
+	cl_dbg(dev, cl, "sending flow control\n");
+	return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD, len);
+}
+
+/**
+ * mei_hbm_add_single_flow_creds - adds single buffer credentials.
+ *
+ * @dev: the device structure
+ * @flow: flow control.
+ *
+ * Return: 0 on success, < 0 otherwise
+ */
+static int mei_hbm_add_single_flow_creds(struct mei_device *dev,
+				  struct hbm_flow_control *flow)
+{
+	struct mei_me_client *me_cl;
+	int rets;
+
+	me_cl = mei_me_cl_by_id(dev, flow->me_addr);
+	if (!me_cl) {
+		dev_err(dev->dev, "no such me client %d\n",
+			flow->me_addr);
+		return -ENOENT;
+	}
+
+	if (WARN_ON(me_cl->props.single_recv_buf == 0)) {
+		rets = -EINVAL;
+		goto out;
+	}
+
+	me_cl->mei_flow_ctrl_creds++;
+	dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
+	    flow->me_addr, me_cl->mei_flow_ctrl_creds);
+
+	rets = 0;
+out:
+	mei_me_cl_put(me_cl);
+	return rets;
+}
+
+/**
+ * mei_hbm_cl_flow_control_res - flow control response from me
+ *
+ * @dev: the device structure
+ * @flow_control: flow control response bus message
+ */
+static void mei_hbm_cl_flow_control_res(struct mei_device *dev,
+					struct hbm_flow_control *flow_control)
+{
+	struct mei_cl *cl;
+
+	if (!flow_control->host_addr) {
+		/* single receive buffer */
+		mei_hbm_add_single_flow_creds(dev, flow_control);
+		return;
+	}
+
+	cl = mei_hbm_cl_find_by_cmd(dev, flow_control);
+	if (cl) {
+		cl->mei_flow_ctrl_creds++;
+		cl_dbg(dev, cl, "flow control creds = %d.\n",
+				cl->mei_flow_ctrl_creds);
+	}
+}
+
+
+/**
+ * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
+ *
+ * @dev: the device structure
+ * @cl: a client to disconnect from
+ *
+ * Return: -EIO on write failure
+ */
+int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
+{
+	const size_t len = sizeof(struct hbm_client_connect_request);
+
+	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD, len);
+}
+
+/**
+ * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
+ *
+ * @dev: the device structure
+ * @cl: a client to disconnect from
+ *
+ * Return: -EIO on write failure
+ */
+int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
+{
+	const size_t len = sizeof(struct hbm_client_connect_response);
+
+	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD, len);
+}
+
+/**
+ * mei_hbm_cl_disconnect_res - update the client state according
+ *       disconnect response
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ * @cmd: disconnect client response host bus message
+ */
+static void mei_hbm_cl_disconnect_res(struct mei_device *dev, struct mei_cl *cl,
+				      struct mei_hbm_cl_cmd *cmd)
+{
+	struct hbm_client_connect_response *rs =
+		(struct hbm_client_connect_response *)cmd;
+
+	cl_dbg(dev, cl, "hbm: disconnect response status=%d\n", rs->status);
+
+	if (rs->status == MEI_CL_DISCONN_SUCCESS)
+		cl->state = MEI_FILE_DISCONNECTED;
+	cl->status = 0;
+}
+
+/**
+ * mei_hbm_cl_connect_req - send connection request to specific me client
+ *
+ * @dev: the device structure
+ * @cl: a client to connect to
+ *
+ * Return: -EIO on write failure
+ */
+int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
+{
+	const size_t len = sizeof(struct hbm_client_connect_request);
+
+	return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD, len);
+}
+
+/**
+ * mei_hbm_cl_connect_res - update the client state according
+ *        connection response
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ * @cmd: connect client response host bus message
+ */
+static void mei_hbm_cl_connect_res(struct mei_device *dev, struct mei_cl *cl,
+				   struct mei_hbm_cl_cmd *cmd)
+{
+	struct hbm_client_connect_response *rs =
+		(struct hbm_client_connect_response *)cmd;
+
+	cl_dbg(dev, cl, "hbm: connect response status=%s\n",
+			mei_cl_conn_status_str(rs->status));
+
+	if (rs->status == MEI_CL_CONN_SUCCESS)
+		cl->state = MEI_FILE_CONNECTED;
+	else
+		cl->state = MEI_FILE_DISCONNECTED;
+	cl->status = mei_cl_conn_status_to_errno(rs->status);
+}
+
+/**
+ * mei_hbm_cl_res - process hbm response received on behalf
+ *         an client
+ *
+ * @dev: the device structure
+ * @rs:  hbm client message
+ * @fop_type: file operation type
+ */
+static void mei_hbm_cl_res(struct mei_device *dev,
+			   struct mei_hbm_cl_cmd *rs,
+			   enum mei_cb_file_ops fop_type)
+{
+	struct mei_cl *cl;
+	struct mei_cl_cb *cb, *next;
+
+	cl = NULL;
+	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list.list, list) {
+
+		cl = cb->cl;
+
+		if (cb->fop_type != fop_type)
+			continue;
+
+		if (mei_hbm_cl_addr_equal(cl, rs)) {
+			list_del_init(&cb->list);
+			break;
+		}
+	}
+
+	if (!cl)
+		return;
+
+	switch (fop_type) {
+	case MEI_FOP_CONNECT:
+		mei_hbm_cl_connect_res(dev, cl, rs);
+		break;
+	case MEI_FOP_DISCONNECT:
+		mei_hbm_cl_disconnect_res(dev, cl, rs);
+		break;
+	default:
+		return;
+	}
+
+	cl->timer_count = 0;
+	wake_up(&cl->wait);
+}
+
+
+/**
+ * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
+ *  host sends disconnect response
+ *
+ * @dev: the device structure.
+ * @disconnect_req: disconnect request bus message from the me
+ *
+ * Return: -ENOMEM on allocation failure
+ */
+static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
+		struct hbm_client_connect_request *disconnect_req)
+{
+	struct mei_cl *cl;
+	struct mei_cl_cb *cb;
+
+	cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
+	if (cl) {
+		cl_dbg(dev, cl, "disconnect request received\n");
+		cl->state = MEI_FILE_DISCONNECTED;
+		cl->timer_count = 0;
+
+		cb = mei_io_cb_init(cl, MEI_FOP_DISCONNECT_RSP, NULL);
+		if (!cb)
+			return -ENOMEM;
+		cl_dbg(dev, cl, "add disconnect response as first\n");
+		list_add(&cb->list, &dev->ctrl_wr_list.list);
+	}
+	return 0;
+}
+
+/**
+ * mei_hbm_config_features - check what hbm features and commands
+ *        are supported by the fw
+ *
+ * @dev: the device structure
+ */
+static void mei_hbm_config_features(struct mei_device *dev)
+{
+	/* Power Gating Isolation Support */
+	dev->hbm_f_pg_supported = 0;
+	if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
+		dev->hbm_f_pg_supported = 1;
+
+	if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
+	    dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
+		dev->hbm_f_pg_supported = 1;
+}
+
+/**
+ * mei_hbm_version_is_supported - checks whether the driver can
+ *     support the hbm version of the device
+ *
+ * @dev: the device structure
+ * Return: true if driver can support hbm version of the device
+ */
+bool mei_hbm_version_is_supported(struct mei_device *dev)
+{
+	return	(dev->version.major_version < HBM_MAJOR_VERSION) ||
+		(dev->version.major_version == HBM_MAJOR_VERSION &&
+		 dev->version.minor_version <= HBM_MINOR_VERSION);
+}
+
+/**
+ * mei_hbm_dispatch - bottom half read routine after ISR to
+ * handle the read bus message cmd processing.
+ *
+ * @dev: the device structure
+ * @hdr: header of bus message
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
+{
+	struct mei_bus_message *mei_msg;
+	struct hbm_host_version_response *version_res;
+	struct hbm_props_response *props_res;
+	struct hbm_host_enum_response *enum_res;
+
+	struct mei_hbm_cl_cmd *cl_cmd;
+	struct hbm_client_connect_request *disconnect_req;
+	struct hbm_flow_control *flow_control;
+
+	/* read the message to our buffer */
+	BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
+	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
+	mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
+	cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;
+
+	/* ignore spurious message and prevent reset nesting
+	 * hbm is put to idle during system reset
+	 */
+	if (dev->hbm_state == MEI_HBM_IDLE) {
+		dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
+		return 0;
+	}
+
+	switch (mei_msg->hbm_cmd) {
+	case HOST_START_RES_CMD:
+		dev_dbg(dev->dev, "hbm: start: response message received.\n");
+
+		dev->init_clients_timer = 0;
+
+		version_res = (struct hbm_host_version_response *)mei_msg;
+
+		dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
+				HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
+				version_res->me_max_version.major_version,
+				version_res->me_max_version.minor_version);
+
+		if (version_res->host_version_supported) {
+			dev->version.major_version = HBM_MAJOR_VERSION;
+			dev->version.minor_version = HBM_MINOR_VERSION;
+		} else {
+			dev->version.major_version =
+				version_res->me_max_version.major_version;
+			dev->version.minor_version =
+				version_res->me_max_version.minor_version;
+		}
+
+		if (!mei_hbm_version_is_supported(dev)) {
+			dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");
+
+			dev->hbm_state = MEI_HBM_STOPPED;
+			if (mei_hbm_stop_req(dev)) {
+				dev_err(dev->dev, "hbm: start: failed to send stop request\n");
+				return -EIO;
+			}
+			break;
+		}
+
+		mei_hbm_config_features(dev);
+
+		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
+		    dev->hbm_state != MEI_HBM_STARTING) {
+			dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		if (mei_hbm_enum_clients_req(dev)) {
+			dev_err(dev->dev, "hbm: start: failed to send enumeration request\n");
+			return -EIO;
+		}
+
+		wake_up(&dev->wait_hbm_start);
+		break;
+
+	case CLIENT_CONNECT_RES_CMD:
+		dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
+		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
+		break;
+
+	case CLIENT_DISCONNECT_RES_CMD:
+		dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
+		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
+		break;
+
+	case MEI_FLOW_CONTROL_CMD:
+		dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");
+
+		flow_control = (struct hbm_flow_control *) mei_msg;
+		mei_hbm_cl_flow_control_res(dev, flow_control);
+		break;
+
+	case MEI_PG_ISOLATION_ENTRY_RES_CMD:
+		dev_dbg(dev->dev, "power gate isolation entry response received\n");
+		dev->pg_event = MEI_PG_EVENT_RECEIVED;
+		if (waitqueue_active(&dev->wait_pg))
+			wake_up(&dev->wait_pg);
+		break;
+
+	case MEI_PG_ISOLATION_EXIT_REQ_CMD:
+		dev_dbg(dev->dev, "power gate isolation exit request received\n");
+		dev->pg_event = MEI_PG_EVENT_RECEIVED;
+		if (waitqueue_active(&dev->wait_pg))
+			wake_up(&dev->wait_pg);
+		else
+			/*
+			* If the driver is not waiting on this then
+			* this is HW initiated exit from PG.
+			* Start runtime pm resume sequence to exit from PG.
+			*/
+			pm_request_resume(dev->dev);
+		break;
+
+	case HOST_CLIENT_PROPERTIES_RES_CMD:
+		dev_dbg(dev->dev, "hbm: properties response: message received.\n");
+
+		dev->init_clients_timer = 0;
+
+		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
+		    dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
+			dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		props_res = (struct hbm_props_response *)mei_msg;
+
+		if (props_res->status) {
+			dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
+				props_res->status,
+				mei_hbm_status_str(props_res->status));
+			return -EPROTO;
+		}
+
+		mei_hbm_me_cl_add(dev, props_res);
+
+		dev->me_client_index++;
+
+		/* request property for the next client */
+		if (mei_hbm_prop_req(dev))
+			return -EIO;
+
+		break;
+
+	case HOST_ENUM_RES_CMD:
+		dev_dbg(dev->dev, "hbm: enumeration response: message received\n");
+
+		dev->init_clients_timer = 0;
+
+		enum_res = (struct hbm_host_enum_response *) mei_msg;
+		BUILD_BUG_ON(sizeof(dev->me_clients_map)
+				< sizeof(enum_res->valid_addresses));
+		memcpy(dev->me_clients_map, enum_res->valid_addresses,
+				sizeof(enum_res->valid_addresses));
+
+		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
+		    dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
+			dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
+
+		/* first property request */
+		if (mei_hbm_prop_req(dev))
+			return -EIO;
+
+		break;
+
+	case HOST_STOP_RES_CMD:
+		dev_dbg(dev->dev, "hbm: stop response: message received\n");
+
+		dev->init_clients_timer = 0;
+
+		if (dev->hbm_state != MEI_HBM_STOPPED) {
+			dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		dev->dev_state = MEI_DEV_POWER_DOWN;
+		dev_info(dev->dev, "hbm: stop response: resetting.\n");
+		/* force the reset */
+		return -EPROTO;
+		break;
+
+	case CLIENT_DISCONNECT_REQ_CMD:
+		dev_dbg(dev->dev, "hbm: disconnect request: message received\n");
+
+		disconnect_req = (struct hbm_client_connect_request *)mei_msg;
+		mei_hbm_fw_disconnect_req(dev, disconnect_req);
+		break;
+
+	case ME_STOP_REQ_CMD:
+		dev_dbg(dev->dev, "hbm: stop request: message received\n");
+		dev->hbm_state = MEI_HBM_STOPPED;
+		if (mei_hbm_stop_req(dev)) {
+			dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
+			return -EIO;
+		}
+		break;
+	default:
+		BUG();
+		break;
+
+	}
+	return 0;
+}
+