Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1619 insertions, 0 deletions

diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c
new file mode 100644
index 0000000000..12a62a911e
--- /dev/null
+++ b/drivers/misc/mei/hbm.c
@@ -0,0 +1,1619 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2003-2022, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+#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);
+	MEI_CL_CS(NOT_ALLOWED);
+	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(DR_SETUP);
+	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;
+	case MEI_CL_CONN_NOT_ALLOWED:      return -EBUSY;
+	default:                           return -EINVAL;
+	}
+}
+
+/**
+ * mei_hbm_write_message - wrapper for sending hbm messages.
+ *
+ * @dev: mei device
+ * @hdr: mei header
+ * @data: payload
+ */
+static inline int mei_hbm_write_message(struct mei_device *dev,
+					struct mei_msg_hdr *hdr,
+					const void *data)
+{
+	return mei_write_message(dev, hdr, sizeof(*hdr), data, hdr->length);
+}
+
+/**
+ * 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)
+{
+	mei_me_cl_rm_all(dev);
+
+	mei_hbm_idle(dev);
+}
+
+/**
+ * mei_hbm_hdr - construct hbm header
+ *
+ * @mei_hdr: hbm header
+ * @length: payload length
+ */
+
+static inline void mei_hbm_hdr(struct mei_msg_hdr *mei_hdr, size_t length)
+{
+	memset(mei_hdr, 0, sizeof(*mei_hdr));
+	mei_hdr->length = length;
+	mei_hdr->msg_complete = 1;
+}
+
+/**
+ * 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 = mei_cl_host_addr(cl);
+	cmd->me_addr = mei_cl_me_id(cl);
+}
+
+/**
+ * mei_hbm_cl_write - write simple hbm client message
+ *
+ * @dev: the device structure
+ * @cl: client
+ * @hbm_cmd: host bus message command
+ * @buf: message buffer
+ * @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, void *buf, size_t len)
+{
+	struct mei_msg_hdr mei_hdr;
+
+	mei_hbm_hdr(&mei_hdr, len);
+	mei_hbm_cl_hdr(cl, hbm_cmd, buf, len);
+
+	return mei_hbm_write_message(dev, &mei_hdr, buf);
+}
+
+/**
+ * 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  mei_cl_host_addr(cl) == cmd->host_addr &&
+		mei_cl_me_id(cl) == 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,
+			dev->timeouts.hbm);
+	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;
+	struct hbm_host_version_request req;
+	int ret;
+
+	mei_hbm_reset(dev);
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	/* host start message */
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = HOST_START_REQ_CMD;
+	req.host_version.major_version = HBM_MAJOR_VERSION;
+	req.host_version.minor_version = HBM_MINOR_VERSION;
+
+	dev->hbm_state = MEI_HBM_IDLE;
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	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 = dev->timeouts.client_init;
+	mei_schedule_stall_timer(dev);
+	return 0;
+}
+
+/**
+ * mei_hbm_dma_setup_req() - setup DMA request
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_dma_setup_req(struct mei_device *dev)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_dma_setup_request req;
+	unsigned int i;
+	int ret;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = MEI_HBM_DMA_SETUP_REQ_CMD;
+	for (i = 0; i < DMA_DSCR_NUM; i++) {
+		phys_addr_t paddr;
+
+		paddr = dev->dr_dscr[i].daddr;
+		req.dma_dscr[i].addr_hi = upper_32_bits(paddr);
+		req.dma_dscr[i].addr_lo = lower_32_bits(paddr);
+		req.dma_dscr[i].size = dev->dr_dscr[i].size;
+	}
+
+	mei_dma_ring_reset(dev);
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret) {
+		dev_err(dev->dev, "dma setup request write failed: ret = %d.\n",
+			ret);
+		return ret;
+	}
+
+	dev->hbm_state = MEI_HBM_DR_SETUP;
+	dev->init_clients_timer = dev->timeouts.client_init;
+	mei_schedule_stall_timer(dev);
+	return 0;
+}
+
+/**
+ * mei_hbm_capabilities_req - request capabilities
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_capabilities_req(struct mei_device *dev)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_capability_request req;
+	int ret;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = MEI_HBM_CAPABILITIES_REQ_CMD;
+	if (dev->hbm_f_vt_supported)
+		req.capability_requested[0] |= HBM_CAP_VT;
+
+	if (dev->hbm_f_cd_supported)
+		req.capability_requested[0] |= HBM_CAP_CD;
+
+	if (dev->hbm_f_gsc_supported)
+		req.capability_requested[0] |= HBM_CAP_GSC;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret) {
+		dev_err(dev->dev,
+			"capabilities request write failed: ret = %d.\n", ret);
+		return ret;
+	}
+
+	dev->hbm_state = MEI_HBM_CAP_SETUP;
+	dev->init_clients_timer = dev->timeouts.client_init;
+	mei_schedule_stall_timer(dev);
+	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;
+	struct hbm_host_enum_request req;
+	int ret;
+
+	/* enumerate clients */
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = HOST_ENUM_REQ_CMD;
+	req.flags |= dev->hbm_f_dc_supported ? MEI_HBM_ENUM_F_ALLOW_ADD : 0;
+	req.flags |= dev->hbm_f_ie_supported ?
+			  MEI_HBM_ENUM_F_IMMEDIATE_ENUM : 0;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	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 = dev->timeouts.client_init;
+	mei_schedule_stall_timer(dev);
+	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(*me_cl), 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->tx_flow_ctrl_creds = 0;
+
+	mei_me_cl_add(dev, me_cl);
+
+	return 0;
+}
+
+/**
+ * mei_hbm_add_cl_resp - send response to fw on client add request
+ *
+ * @dev: the device structure
+ * @addr: me address
+ * @status: response status
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_add_cl_resp(struct mei_device *dev, u8 addr, u8 status)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_add_client_response resp;
+	int ret;
+
+	dev_dbg(dev->dev, "adding client response\n");
+
+	mei_hbm_hdr(&mei_hdr, sizeof(resp));
+
+	memset(&resp, 0, sizeof(resp));
+	resp.hbm_cmd = MEI_HBM_ADD_CLIENT_RES_CMD;
+	resp.me_addr = addr;
+	resp.status  = status;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &resp);
+	if (ret)
+		dev_err(dev->dev, "add client response write failed: ret = %d\n",
+			ret);
+	return ret;
+}
+
+/**
+ * mei_hbm_fw_add_cl_req - request from the fw to add a client
+ *
+ * @dev: the device structure
+ * @req: add client request
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_fw_add_cl_req(struct mei_device *dev,
+			      struct hbm_add_client_request *req)
+{
+	int ret;
+	u8 status = MEI_HBMS_SUCCESS;
+
+	BUILD_BUG_ON(sizeof(struct hbm_add_client_request) !=
+			sizeof(struct hbm_props_response));
+
+	ret = mei_hbm_me_cl_add(dev, (struct hbm_props_response *)req);
+	if (ret)
+		status = !MEI_HBMS_SUCCESS;
+
+	if (dev->dev_state == MEI_DEV_ENABLED)
+		schedule_work(&dev->bus_rescan_work);
+
+	return mei_hbm_add_cl_resp(dev, req->me_addr, status);
+}
+
+/**
+ * mei_hbm_cl_notify_req - send notification request
+ *
+ * @dev: the device structure
+ * @cl: a client to disconnect from
+ * @start: true for start false for stop
+ *
+ * Return: 0 on success and -EIO on write failure
+ */
+int mei_hbm_cl_notify_req(struct mei_device *dev,
+			  struct mei_cl *cl, u8 start)
+{
+
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_notification_request req;
+	int ret;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+	mei_hbm_cl_hdr(cl, MEI_HBM_NOTIFY_REQ_CMD, &req, sizeof(req));
+
+	req.start = start;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret)
+		dev_err(dev->dev, "notify request failed: ret = %d\n", ret);
+
+	return ret;
+}
+
+/**
+ *  notify_res_to_fop - convert notification response to the proper
+ *      notification FOP
+ *
+ * @cmd: client notification start response command
+ *
+ * Return:  MEI_FOP_NOTIFY_START or MEI_FOP_NOTIFY_STOP;
+ */
+static inline enum mei_cb_file_ops notify_res_to_fop(struct mei_hbm_cl_cmd *cmd)
+{
+	struct hbm_notification_response *rs =
+		(struct hbm_notification_response *)cmd;
+
+	return mei_cl_notify_req2fop(rs->start);
+}
+
+/**
+ * mei_hbm_cl_notify_start_res - update the client state according
+ *       notify start response
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ * @cmd: client notification start response command
+ */
+static void mei_hbm_cl_notify_start_res(struct mei_device *dev,
+					struct mei_cl *cl,
+					struct mei_hbm_cl_cmd *cmd)
+{
+	struct hbm_notification_response *rs =
+		(struct hbm_notification_response *)cmd;
+
+	cl_dbg(dev, cl, "hbm: notify start response status=%d\n", rs->status);
+
+	if (rs->status == MEI_HBMS_SUCCESS ||
+	    rs->status == MEI_HBMS_ALREADY_STARTED) {
+		cl->notify_en = true;
+		cl->status = 0;
+	} else {
+		cl->status = -EINVAL;
+	}
+}
+
+/**
+ * mei_hbm_cl_notify_stop_res - update the client state according
+ *       notify stop response
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ * @cmd: client notification stop response command
+ */
+static void mei_hbm_cl_notify_stop_res(struct mei_device *dev,
+				       struct mei_cl *cl,
+				       struct mei_hbm_cl_cmd *cmd)
+{
+	struct hbm_notification_response *rs =
+		(struct hbm_notification_response *)cmd;
+
+	cl_dbg(dev, cl, "hbm: notify stop response status=%d\n", rs->status);
+
+	if (rs->status == MEI_HBMS_SUCCESS ||
+	    rs->status == MEI_HBMS_NOT_STARTED) {
+		cl->notify_en = false;
+		cl->status = 0;
+	} else {
+		/* TODO: spec is not clear yet about other possible issues */
+		cl->status = -EINVAL;
+	}
+}
+
+/**
+ * mei_hbm_cl_notify - signal notification event
+ *
+ * @dev: the device structure
+ * @cmd: notification client message
+ */
+static void mei_hbm_cl_notify(struct mei_device *dev,
+			      struct mei_hbm_cl_cmd *cmd)
+{
+	struct mei_cl *cl;
+
+	cl = mei_hbm_cl_find_by_cmd(dev, cmd);
+	if (cl)
+		mei_cl_notify(cl);
+}
+
+/**
+ * mei_hbm_cl_dma_map_req - send client dma map request
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ *
+ * Return: 0 on success and -EIO on write failure
+ */
+int mei_hbm_cl_dma_map_req(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_client_dma_map_request req;
+	int ret;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+
+	req.hbm_cmd = MEI_HBM_CLIENT_DMA_MAP_REQ_CMD;
+	req.client_buffer_id = cl->dma.buffer_id;
+	req.address_lsb = lower_32_bits(cl->dma.daddr);
+	req.address_msb = upper_32_bits(cl->dma.daddr);
+	req.size = cl->dma.size;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret)
+		dev_err(dev->dev, "dma map request failed: ret = %d\n", ret);
+
+	return ret;
+}
+
+/**
+ * mei_hbm_cl_dma_unmap_req - send client dma unmap request
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ *
+ * Return: 0 on success and -EIO on write failure
+ */
+int mei_hbm_cl_dma_unmap_req(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_client_dma_unmap_request req;
+	int ret;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+
+	req.hbm_cmd = MEI_HBM_CLIENT_DMA_UNMAP_REQ_CMD;
+	req.client_buffer_id = cl->dma.buffer_id;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret)
+		dev_err(dev->dev, "dma unmap request failed: ret = %d\n", ret);
+
+	return ret;
+}
+
+static void mei_hbm_cl_dma_map_res(struct mei_device *dev,
+				   struct hbm_client_dma_response *res)
+{
+	struct mei_cl *cl;
+	struct mei_cl_cb *cb, *next;
+
+	cl = NULL;
+	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list, list) {
+		if (cb->fop_type != MEI_FOP_DMA_MAP)
+			continue;
+		if (!cb->cl->dma.buffer_id || cb->cl->dma_mapped)
+			continue;
+
+		cl = cb->cl;
+		break;
+	}
+	if (!cl)
+		return;
+
+	if (res->status) {
+		dev_err(dev->dev, "cl dma map failed %d\n", res->status);
+		cl->status = -EFAULT;
+	} else {
+		dev_dbg(dev->dev, "cl dma map succeeded\n");
+		cl->dma_mapped = 1;
+		cl->status = 0;
+	}
+	wake_up(&cl->wait);
+}
+
+static void mei_hbm_cl_dma_unmap_res(struct mei_device *dev,
+				     struct hbm_client_dma_response *res)
+{
+	struct mei_cl *cl;
+	struct mei_cl_cb *cb, *next;
+
+	cl = NULL;
+	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list, list) {
+		if (cb->fop_type != MEI_FOP_DMA_UNMAP)
+			continue;
+		if (!cb->cl->dma.buffer_id || !cb->cl->dma_mapped)
+			continue;
+
+		cl = cb->cl;
+		break;
+	}
+	if (!cl)
+		return;
+
+	if (res->status) {
+		dev_err(dev->dev, "cl dma unmap failed %d\n", res->status);
+		cl->status = -EFAULT;
+	} else {
+		dev_dbg(dev->dev, "cl dma unmap succeeded\n");
+		cl->dma_mapped = 0;
+		cl->status = 0;
+	}
+	wake_up(&cl->wait);
+}
+
+/**
+ * mei_hbm_prop_req - request property for a single client
+ *
+ * @dev: the device structure
+ * @start_idx: client index to start search
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_prop_req(struct mei_device *dev, unsigned long start_idx)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_props_request req;
+	unsigned long addr;
+	int ret;
+
+	addr = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, start_idx);
+
+	/* We got all client properties */
+	if (addr == MEI_CLIENTS_MAX) {
+		dev->hbm_state = MEI_HBM_STARTED;
+		mei_host_client_init(dev);
+		return 0;
+	}
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+
+	req.hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
+	req.me_addr = addr;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret) {
+		dev_err(dev->dev, "properties request write failed: ret = %d\n",
+			ret);
+		return ret;
+	}
+
+	dev->init_clients_timer = dev->timeouts.client_init;
+	mei_schedule_stall_timer(dev);
+
+	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;
+	struct hbm_power_gate req;
+	int ret;
+
+	if (!dev->hbm_f_pg_supported)
+		return -EOPNOTSUPP;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = pg_cmd;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	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;
+	struct hbm_host_stop_request req;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+	req.hbm_cmd = HOST_STOP_REQ_CMD;
+	req.reason = DRIVER_STOP_REQUEST;
+
+	return mei_hbm_write_message(dev, &mei_hdr, &req);
+}
+
+/**
+ * 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)
+{
+	struct hbm_flow_control req;
+
+	cl_dbg(dev, cl, "sending flow control\n");
+	return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD,
+				&req, sizeof(req));
+}
+
+/**
+ * mei_hbm_add_single_tx_flow_ctrl_creds - adds single buffer credentials.
+ *
+ * @dev: the device structure
+ * @fctrl: flow control response bus message
+ *
+ * Return: 0 on success, < 0 otherwise
+ */
+static int mei_hbm_add_single_tx_flow_ctrl_creds(struct mei_device *dev,
+						 struct hbm_flow_control *fctrl)
+{
+	struct mei_me_client *me_cl;
+	int rets;
+
+	me_cl = mei_me_cl_by_id(dev, fctrl->me_addr);
+	if (!me_cl) {
+		dev_err(dev->dev, "no such me client %d\n", fctrl->me_addr);
+		return -ENOENT;
+	}
+
+	if (WARN_ON(me_cl->props.single_recv_buf == 0)) {
+		rets = -EINVAL;
+		goto out;
+	}
+
+	me_cl->tx_flow_ctrl_creds++;
+	dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
+		fctrl->me_addr, me_cl->tx_flow_ctrl_creds);
+
+	rets = 0;
+out:
+	mei_me_cl_put(me_cl);
+	return rets;
+}
+
+/**
+ * mei_hbm_cl_tx_flow_ctrl_creds_res - flow control response from me
+ *
+ * @dev: the device structure
+ * @fctrl: flow control response bus message
+ */
+static void mei_hbm_cl_tx_flow_ctrl_creds_res(struct mei_device *dev,
+					       struct hbm_flow_control *fctrl)
+{
+	struct mei_cl *cl;
+
+	if (!fctrl->host_addr) {
+		/* single receive buffer */
+		mei_hbm_add_single_tx_flow_ctrl_creds(dev, fctrl);
+		return;
+	}
+
+	cl = mei_hbm_cl_find_by_cmd(dev, fctrl);
+	if (cl) {
+		cl->tx_flow_ctrl_creds++;
+		cl_dbg(dev, cl, "flow control creds = %d.\n",
+				cl->tx_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)
+{
+	struct hbm_client_connect_request req;
+
+	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD,
+				&req, sizeof(req));
+}
+
+/**
+ * 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)
+{
+	struct hbm_client_connect_response resp;
+
+	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD,
+				&resp, sizeof(resp));
+}
+
+/**
+ * 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_DISCONNECT_REPLY;
+	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)
+{
+	struct hbm_client_connect_request req;
+
+	return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD,
+				&req, sizeof(req));
+}
+
+/**
+ * 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_DISCONNECT_REPLY;
+		if (rs->status == MEI_CL_CONN_NOT_FOUND) {
+			mei_me_cl_del(dev, cl->me_cl);
+			if (dev->dev_state == MEI_DEV_ENABLED)
+				schedule_work(&dev->bus_rescan_work);
+		}
+	}
+	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) {
+
+		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;
+	case MEI_FOP_NOTIFY_START:
+		mei_hbm_cl_notify_start_res(dev, cl, rs);
+		break;
+	case MEI_FOP_NOTIFY_STOP:
+		mei_hbm_cl_notify_stop_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_warn(dev, cl, "fw disconnect request received\n");
+		cl->state = MEI_FILE_DISCONNECTING;
+		cl->timer_count = 0;
+
+		cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT_RSP,
+					       NULL);
+		if (!cb)
+			return -ENOMEM;
+	}
+	return 0;
+}
+
+/**
+ * mei_hbm_pg_enter_res - PG enter response received
+ *
+ * @dev: the device structure.
+ *
+ * Return: 0 on success, -EPROTO on state mismatch
+ */
+static int mei_hbm_pg_enter_res(struct mei_device *dev)
+{
+	if (mei_pg_state(dev) != MEI_PG_OFF ||
+	    dev->pg_event != MEI_PG_EVENT_WAIT) {
+		dev_err(dev->dev, "hbm: pg entry response: state mismatch [%s, %d]\n",
+			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
+		return -EPROTO;
+	}
+
+	dev->pg_event = MEI_PG_EVENT_RECEIVED;
+	wake_up(&dev->wait_pg);
+
+	return 0;
+}
+
+/**
+ * mei_hbm_pg_resume - process with PG resume
+ *
+ * @dev: the device structure.
+ */
+void mei_hbm_pg_resume(struct mei_device *dev)
+{
+	pm_request_resume(dev->dev);
+}
+EXPORT_SYMBOL_GPL(mei_hbm_pg_resume);
+
+/**
+ * mei_hbm_pg_exit_res - PG exit response received
+ *
+ * @dev: the device structure.
+ *
+ * Return: 0 on success, -EPROTO on state mismatch
+ */
+static int mei_hbm_pg_exit_res(struct mei_device *dev)
+{
+	if (mei_pg_state(dev) != MEI_PG_ON ||
+	    (dev->pg_event != MEI_PG_EVENT_WAIT &&
+	     dev->pg_event != MEI_PG_EVENT_IDLE)) {
+		dev_err(dev->dev, "hbm: pg exit response: state mismatch [%s, %d]\n",
+			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
+		return -EPROTO;
+	}
+
+	switch (dev->pg_event) {
+	case MEI_PG_EVENT_WAIT:
+		dev->pg_event = MEI_PG_EVENT_RECEIVED;
+		wake_up(&dev->wait_pg);
+		break;
+	case MEI_PG_EVENT_IDLE:
+		/*
+		* 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.
+		*/
+		dev->pg_event = MEI_PG_EVENT_RECEIVED;
+		mei_hbm_pg_resume(dev);
+		break;
+	default:
+		WARN(1, "hbm: pg exit response: unexpected pg event = %d\n",
+		     dev->pg_event);
+		return -EPROTO;
+	}
+
+	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;
+
+	dev->hbm_f_dc_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_DC)
+		dev->hbm_f_dc_supported = 1;
+
+	dev->hbm_f_ie_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_IE)
+		dev->hbm_f_ie_supported = 1;
+
+	/* disconnect on connect timeout instead of link reset */
+	dev->hbm_f_dot_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_DOT)
+		dev->hbm_f_dot_supported = 1;
+
+	/* Notification Event Support */
+	dev->hbm_f_ev_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_EV)
+		dev->hbm_f_ev_supported = 1;
+
+	/* Fixed Address Client Support */
+	dev->hbm_f_fa_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_FA)
+		dev->hbm_f_fa_supported = 1;
+
+	/* OS ver message Support */
+	dev->hbm_f_os_supported = 0;
+	if (dev->version.major_version >= HBM_MAJOR_VERSION_OS)
+		dev->hbm_f_os_supported = 1;
+
+	/* DMA Ring Support */
+	dev->hbm_f_dr_supported = 0;
+	if (dev->version.major_version > HBM_MAJOR_VERSION_DR ||
+	    (dev->version.major_version == HBM_MAJOR_VERSION_DR &&
+	     dev->version.minor_version >= HBM_MINOR_VERSION_DR))
+		dev->hbm_f_dr_supported = 1;
+
+	/* VTag Support */
+	dev->hbm_f_vt_supported = 0;
+	if (dev->version.major_version > HBM_MAJOR_VERSION_VT ||
+	    (dev->version.major_version == HBM_MAJOR_VERSION_VT &&
+	     dev->version.minor_version >= HBM_MINOR_VERSION_VT))
+		dev->hbm_f_vt_supported = 1;
+
+	/* GSC support */
+	if (dev->version.major_version > HBM_MAJOR_VERSION_GSC ||
+	    (dev->version.major_version == HBM_MAJOR_VERSION_GSC &&
+	     dev->version.minor_version >= HBM_MINOR_VERSION_GSC))
+		dev->hbm_f_gsc_supported = 1;
+
+	/* Capability message Support */
+	dev->hbm_f_cap_supported = 0;
+	if (dev->version.major_version > HBM_MAJOR_VERSION_CAP ||
+	    (dev->version.major_version == HBM_MAJOR_VERSION_CAP &&
+	     dev->version.minor_version >= HBM_MINOR_VERSION_CAP))
+		dev->hbm_f_cap_supported = 1;
+
+	/* Client DMA Support */
+	dev->hbm_f_cd_supported = 0;
+	if (dev->version.major_version > HBM_MAJOR_VERSION_CD ||
+	    (dev->version.major_version == HBM_MAJOR_VERSION_CD &&
+	     dev->version.minor_version >= HBM_MINOR_VERSION_CD))
+		dev->hbm_f_cd_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 hbm_dma_setup_response *dma_setup_res;
+	struct hbm_add_client_request *add_cl_req;
+	struct hbm_capability_response *capability_res;
+	int ret;
+
+	struct mei_hbm_cl_cmd *cl_cmd;
+	struct hbm_client_connect_request *disconnect_req;
+	struct hbm_flow_control *fctrl;
+	struct hbm_client_dma_response *client_dma_res;
+
+	/* 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) {
+			if (dev->dev_state == MEI_DEV_POWER_DOWN ||
+			    dev->dev_state == MEI_DEV_POWERING_DOWN) {
+				dev_dbg(dev->dev, "hbm: start: on shutdown, ignoring\n");
+				return 0;
+			}
+			dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		if (dev->hbm_f_cap_supported) {
+			if (mei_hbm_capabilities_req(dev))
+				return -EIO;
+			wake_up(&dev->wait_hbm_start);
+			break;
+		}
+
+		if (dev->hbm_f_dr_supported) {
+			if (mei_dmam_ring_alloc(dev))
+				dev_info(dev->dev, "running w/o dma ring\n");
+			if (mei_dma_ring_is_allocated(dev)) {
+				if (mei_hbm_dma_setup_req(dev))
+					return -EIO;
+
+				wake_up(&dev->wait_hbm_start);
+				break;
+			}
+		}
+
+		dev->hbm_f_dr_supported = 0;
+		mei_dmam_ring_free(dev);
+
+		if (mei_hbm_enum_clients_req(dev))
+			return -EIO;
+
+		wake_up(&dev->wait_hbm_start);
+		break;
+
+	case MEI_HBM_CAPABILITIES_RES_CMD:
+		dev_dbg(dev->dev, "hbm: capabilities response: message received.\n");
+
+		dev->init_clients_timer = 0;
+
+		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
+		    dev->hbm_state != MEI_HBM_CAP_SETUP) {
+			if (dev->dev_state == MEI_DEV_POWER_DOWN ||
+			    dev->dev_state == MEI_DEV_POWERING_DOWN) {
+				dev_dbg(dev->dev, "hbm: capabilities response: on shutdown, ignoring\n");
+				return 0;
+			}
+			dev_err(dev->dev, "hbm: capabilities response: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		capability_res = (struct hbm_capability_response *)mei_msg;
+		if (!(capability_res->capability_granted[0] & HBM_CAP_VT))
+			dev->hbm_f_vt_supported = 0;
+		if (!(capability_res->capability_granted[0] & HBM_CAP_CD))
+			dev->hbm_f_cd_supported = 0;
+
+		if (!(capability_res->capability_granted[0] & HBM_CAP_GSC))
+			dev->hbm_f_gsc_supported = 0;
+
+		if (dev->hbm_f_dr_supported) {
+			if (mei_dmam_ring_alloc(dev))
+				dev_info(dev->dev, "running w/o dma ring\n");
+			if (mei_dma_ring_is_allocated(dev)) {
+				if (mei_hbm_dma_setup_req(dev))
+					return -EIO;
+				break;
+			}
+		}
+
+		dev->hbm_f_dr_supported = 0;
+		mei_dmam_ring_free(dev);
+
+		if (mei_hbm_enum_clients_req(dev))
+			return -EIO;
+		break;
+
+	case MEI_HBM_DMA_SETUP_RES_CMD:
+		dev_dbg(dev->dev, "hbm: dma setup response: message received.\n");
+
+		dev->init_clients_timer = 0;
+
+		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
+		    dev->hbm_state != MEI_HBM_DR_SETUP) {
+			if (dev->dev_state == MEI_DEV_POWER_DOWN ||
+			    dev->dev_state == MEI_DEV_POWERING_DOWN) {
+				dev_dbg(dev->dev, "hbm: dma setup response: on shutdown, ignoring\n");
+				return 0;
+			}
+			dev_err(dev->dev, "hbm: dma setup response: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+
+		dma_setup_res = (struct hbm_dma_setup_response *)mei_msg;
+
+		if (dma_setup_res->status) {
+			u8 status = dma_setup_res->status;
+
+			if (status == MEI_HBMS_NOT_ALLOWED) {
+				dev_dbg(dev->dev, "hbm: dma setup not allowed\n");
+			} else {
+				dev_info(dev->dev, "hbm: dma setup response: failure = %d %s\n",
+					 status,
+					 mei_hbm_status_str(status));
+			}
+			dev->hbm_f_dr_supported = 0;
+			mei_dmam_ring_free(dev);
+		}
+
+		if (mei_hbm_enum_clients_req(dev))
+			return -EIO;
+		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");
+
+		fctrl = (struct hbm_flow_control *)mei_msg;
+		mei_hbm_cl_tx_flow_ctrl_creds_res(dev, fctrl);
+		break;
+
+	case MEI_PG_ISOLATION_ENTRY_RES_CMD:
+		dev_dbg(dev->dev, "hbm: power gate isolation entry response received\n");
+		ret = mei_hbm_pg_enter_res(dev);
+		if (ret)
+			return ret;
+		break;
+
+	case MEI_PG_ISOLATION_EXIT_REQ_CMD:
+		dev_dbg(dev->dev, "hbm: power gate isolation exit request received\n");
+		ret = mei_hbm_pg_exit_res(dev);
+		if (ret)
+			return ret;
+		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) {
+			if (dev->dev_state == MEI_DEV_POWER_DOWN ||
+			    dev->dev_state == MEI_DEV_POWERING_DOWN) {
+				dev_dbg(dev->dev, "hbm: properties response: on shutdown, ignoring\n");
+				return 0;
+			}
+			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 == MEI_HBMS_CLIENT_NOT_FOUND) {
+			dev_dbg(dev->dev, "hbm: properties response: %d CLIENT_NOT_FOUND\n",
+				props_res->me_addr);
+		} else 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;
+		} else {
+			mei_hbm_me_cl_add(dev, props_res);
+		}
+
+		/* request property for the next client */
+		if (mei_hbm_prop_req(dev, props_res->me_addr + 1))
+			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) {
+			if (dev->dev_state == MEI_DEV_POWER_DOWN ||
+			    dev->dev_state == MEI_DEV_POWERING_DOWN) {
+				dev_dbg(dev->dev, "hbm: enumeration response: on shutdown, ignoring\n");
+				return 0;
+			}
+			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, 0))
+			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;
+		}
+
+		mei_set_devstate(dev, MEI_DEV_POWER_DOWN);
+		dev_info(dev->dev, "hbm: stop response: resetting.\n");
+		/* force the reset */
+		return -EPROTO;
+
+	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;
+
+	case MEI_HBM_ADD_CLIENT_REQ_CMD:
+		dev_dbg(dev->dev, "hbm: add client request received\n");
+		/*
+		 * after the host receives the enum_resp
+		 * message clients may be added or removed
+		 */
+		if (dev->hbm_state <= MEI_HBM_ENUM_CLIENTS ||
+		    dev->hbm_state >= MEI_HBM_STOPPED) {
+			dev_err(dev->dev, "hbm: add client: state mismatch, [%d, %d]\n",
+				dev->dev_state, dev->hbm_state);
+			return -EPROTO;
+		}
+		add_cl_req = (struct hbm_add_client_request *)mei_msg;
+		ret = mei_hbm_fw_add_cl_req(dev, add_cl_req);
+		if (ret) {
+			dev_err(dev->dev, "hbm: add client: failed to send response %d\n",
+				ret);
+			return -EIO;
+		}
+		dev_dbg(dev->dev, "hbm: add client request processed\n");
+		break;
+
+	case MEI_HBM_NOTIFY_RES_CMD:
+		dev_dbg(dev->dev, "hbm: notify response received\n");
+		mei_hbm_cl_res(dev, cl_cmd, notify_res_to_fop(cl_cmd));
+		break;
+
+	case MEI_HBM_NOTIFICATION_CMD:
+		dev_dbg(dev->dev, "hbm: notification\n");
+		mei_hbm_cl_notify(dev, cl_cmd);
+		break;
+
+	case MEI_HBM_CLIENT_DMA_MAP_RES_CMD:
+		dev_dbg(dev->dev, "hbm: client dma map response: message received.\n");
+		client_dma_res = (struct hbm_client_dma_response *)mei_msg;
+		mei_hbm_cl_dma_map_res(dev, client_dma_res);
+		break;
+
+	case MEI_HBM_CLIENT_DMA_UNMAP_RES_CMD:
+		dev_dbg(dev->dev, "hbm: client dma unmap response: message received.\n");
+		client_dma_res = (struct hbm_client_dma_response *)mei_msg;
+		mei_hbm_cl_dma_unmap_res(dev, client_dma_res);
+		break;
+
+	default:
+		WARN(1, "hbm: wrong command %d\n", mei_msg->hbm_cmd);
+		return -EPROTO;
+
+	}
+	return 0;
+}
+