path: root/drivers/misc/mei/hbm.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2003-2020, 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