| /* |
| * |
| * 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/pci.h> |
| #include "mei_dev.h" |
| #include <linux/mei.h> |
| #include "interface.h" |
| |
| |
| |
| /** |
| * mei_set_csr_register - writes H_CSR register to the mei device, |
| * and ignores the H_IS bit for it is write-one-to-zero. |
| * |
| * @dev: the device structure |
| */ |
| void mei_hcsr_set(struct mei_device *dev) |
| { |
| if ((dev->host_hw_state & H_IS) == H_IS) |
| dev->host_hw_state &= ~H_IS; |
| mei_reg_write(dev, H_CSR, dev->host_hw_state); |
| dev->host_hw_state = mei_hcsr_read(dev); |
| } |
| |
| /** |
| * mei_csr_enable_interrupts - enables mei device interrupts |
| * |
| * @dev: the device structure |
| */ |
| void mei_enable_interrupts(struct mei_device *dev) |
| { |
| dev->host_hw_state |= H_IE; |
| mei_hcsr_set(dev); |
| } |
| |
| /** |
| * mei_csr_disable_interrupts - disables mei device interrupts |
| * |
| * @dev: the device structure |
| */ |
| void mei_disable_interrupts(struct mei_device *dev) |
| { |
| dev->host_hw_state &= ~H_IE; |
| mei_hcsr_set(dev); |
| } |
| |
| /** |
| * mei_hbuf_filled_slots - gets number of device filled buffer slots |
| * |
| * @device: the device structure |
| * |
| * returns number of filled slots |
| */ |
| static unsigned char mei_hbuf_filled_slots(struct mei_device *dev) |
| { |
| char read_ptr, write_ptr; |
| |
| dev->host_hw_state = mei_hcsr_read(dev); |
| |
| read_ptr = (char) ((dev->host_hw_state & H_CBRP) >> 8); |
| write_ptr = (char) ((dev->host_hw_state & H_CBWP) >> 16); |
| |
| return (unsigned char) (write_ptr - read_ptr); |
| } |
| |
| /** |
| * mei_hbuf_is_empty - checks if host buffer is empty. |
| * |
| * @dev: the device structure |
| * |
| * returns true if empty, false - otherwise. |
| */ |
| bool mei_hbuf_is_empty(struct mei_device *dev) |
| { |
| return mei_hbuf_filled_slots(dev) == 0; |
| } |
| |
| /** |
| * mei_hbuf_empty_slots - counts write empty slots. |
| * |
| * @dev: the device structure |
| * |
| * returns -1(ESLOTS_OVERFLOW) if overflow, otherwise empty slots count |
| */ |
| int mei_hbuf_empty_slots(struct mei_device *dev) |
| { |
| unsigned char filled_slots, empty_slots; |
| |
| filled_slots = mei_hbuf_filled_slots(dev); |
| empty_slots = dev->hbuf_depth - filled_slots; |
| |
| /* check for overflow */ |
| if (filled_slots > dev->hbuf_depth) |
| return -EOVERFLOW; |
| |
| return empty_slots; |
| } |
| |
| /** |
| * mei_write_message - writes a message to mei device. |
| * |
| * @dev: the device structure |
| * @header: header of message |
| * @write_buffer: message buffer will be written |
| * @write_length: message size will be written |
| * |
| * This function returns -EIO if write has failed |
| */ |
| int mei_write_message(struct mei_device *dev, struct mei_msg_hdr *header, |
| unsigned char *buf, unsigned long length) |
| { |
| unsigned long rem, dw_cnt; |
| u32 *reg_buf = (u32 *)buf; |
| int i; |
| int empty_slots; |
| |
| |
| dev_dbg(&dev->pdev->dev, |
| "mei_write_message header=%08x.\n", |
| *((u32 *) header)); |
| |
| empty_slots = mei_hbuf_empty_slots(dev); |
| dev_dbg(&dev->pdev->dev, "empty slots = %hu.\n", empty_slots); |
| |
| dw_cnt = mei_data2slots(length); |
| if (empty_slots < 0 || dw_cnt > empty_slots) |
| return -EIO; |
| |
| mei_reg_write(dev, H_CB_WW, *((u32 *) header)); |
| |
| for (i = 0; i < length / 4; i++) |
| mei_reg_write(dev, H_CB_WW, reg_buf[i]); |
| |
| rem = length & 0x3; |
| if (rem > 0) { |
| u32 reg = 0; |
| memcpy(®, &buf[length - rem], rem); |
| mei_reg_write(dev, H_CB_WW, reg); |
| } |
| |
| dev->host_hw_state = mei_hcsr_read(dev); |
| dev->host_hw_state |= H_IG; |
| mei_hcsr_set(dev); |
| dev->me_hw_state = mei_mecsr_read(dev); |
| if ((dev->me_hw_state & ME_RDY_HRA) != ME_RDY_HRA) |
| return -EIO; |
| |
| return 0; |
| } |
| |
| /** |
| * mei_count_full_read_slots - counts read full slots. |
| * |
| * @dev: the device structure |
| * |
| * returns -1(ESLOTS_OVERFLOW) if overflow, otherwise filled slots count |
| */ |
| int mei_count_full_read_slots(struct mei_device *dev) |
| { |
| char read_ptr, write_ptr; |
| unsigned char buffer_depth, filled_slots; |
| |
| dev->me_hw_state = mei_mecsr_read(dev); |
| buffer_depth = (unsigned char)((dev->me_hw_state & ME_CBD_HRA) >> 24); |
| read_ptr = (char) ((dev->me_hw_state & ME_CBRP_HRA) >> 8); |
| write_ptr = (char) ((dev->me_hw_state & ME_CBWP_HRA) >> 16); |
| filled_slots = (unsigned char) (write_ptr - read_ptr); |
| |
| /* check for overflow */ |
| if (filled_slots > buffer_depth) |
| return -EOVERFLOW; |
| |
| dev_dbg(&dev->pdev->dev, "filled_slots =%08x\n", filled_slots); |
| return (int)filled_slots; |
| } |
| |
| /** |
| * mei_read_slots - reads a message from mei device. |
| * |
| * @dev: the device structure |
| * @buffer: message buffer will be written |
| * @buffer_length: message size will be read |
| */ |
| void mei_read_slots(struct mei_device *dev, unsigned char *buffer, |
| unsigned long buffer_length) |
| { |
| u32 *reg_buf = (u32 *)buffer; |
| |
| for (; buffer_length >= sizeof(u32); buffer_length -= sizeof(u32)) |
| *reg_buf++ = mei_mecbrw_read(dev); |
| |
| if (buffer_length > 0) { |
| u32 reg = mei_mecbrw_read(dev); |
| memcpy(reg_buf, ®, buffer_length); |
| } |
| |
| dev->host_hw_state |= H_IG; |
| mei_hcsr_set(dev); |
| } |
| |
| /** |
| * mei_flow_ctrl_creds - checks flow_control credentials. |
| * |
| * @dev: the device structure |
| * @cl: private data of the file object |
| * |
| * returns 1 if mei_flow_ctrl_creds >0, 0 - otherwise. |
| * -ENOENT if mei_cl is not present |
| * -EINVAL if single_recv_buf == 0 |
| */ |
| int mei_flow_ctrl_creds(struct mei_device *dev, struct mei_cl *cl) |
| { |
| int i; |
| |
| if (!dev->me_clients_num) |
| return 0; |
| |
| if (cl->mei_flow_ctrl_creds > 0) |
| return 1; |
| |
| for (i = 0; i < dev->me_clients_num; i++) { |
| struct mei_me_client *me_cl = &dev->me_clients[i]; |
| if (me_cl->client_id == cl->me_client_id) { |
| if (me_cl->mei_flow_ctrl_creds) { |
| if (WARN_ON(me_cl->props.single_recv_buf == 0)) |
| return -EINVAL; |
| return 1; |
| } else { |
| return 0; |
| } |
| } |
| } |
| return -ENOENT; |
| } |
| |
| /** |
| * mei_flow_ctrl_reduce - reduces flow_control. |
| * |
| * @dev: the device structure |
| * @cl: private data of the file object |
| * @returns |
| * 0 on success |
| * -ENOENT when me client is not found |
| * -EINVAL when ctrl credits are <= 0 |
| */ |
| int mei_flow_ctrl_reduce(struct mei_device *dev, struct mei_cl *cl) |
| { |
| int i; |
| |
| if (!dev->me_clients_num) |
| return -ENOENT; |
| |
| for (i = 0; i < dev->me_clients_num; i++) { |
| struct mei_me_client *me_cl = &dev->me_clients[i]; |
| if (me_cl->client_id == cl->me_client_id) { |
| if (me_cl->props.single_recv_buf != 0) { |
| if (WARN_ON(me_cl->mei_flow_ctrl_creds <= 0)) |
| return -EINVAL; |
| dev->me_clients[i].mei_flow_ctrl_creds--; |
| } else { |
| if (WARN_ON(cl->mei_flow_ctrl_creds <= 0)) |
| return -EINVAL; |
| cl->mei_flow_ctrl_creds--; |
| } |
| return 0; |
| } |
| } |
| return -ENOENT; |
| } |
| |
| /** |
| * mei_send_flow_control - sends flow control to fw. |
| * |
| * @dev: the device structure |
| * @cl: private data of the file object |
| * |
| * This function returns -EIO on write failure |
| */ |
| int mei_send_flow_control(struct mei_device *dev, struct mei_cl *cl) |
| { |
| struct mei_msg_hdr *mei_hdr; |
| struct hbm_flow_control *flow_ctrl; |
| const size_t len = sizeof(struct hbm_flow_control); |
| |
| mei_hdr = mei_hbm_hdr(&dev->wr_msg_buf[0], len); |
| |
| flow_ctrl = (struct hbm_flow_control *)&dev->wr_msg_buf[1]; |
| memset(flow_ctrl, 0, len); |
| flow_ctrl->hbm_cmd = MEI_FLOW_CONTROL_CMD; |
| flow_ctrl->host_addr = cl->host_client_id; |
| flow_ctrl->me_addr = cl->me_client_id; |
| /* FIXME: reserved !? */ |
| memset(flow_ctrl->reserved, 0, sizeof(flow_ctrl->reserved)); |
| dev_dbg(&dev->pdev->dev, "sending flow control host client = %d, ME client = %d\n", |
| cl->host_client_id, cl->me_client_id); |
| |
| return mei_write_message(dev, mei_hdr, |
| (unsigned char *) flow_ctrl, len); |
| } |
| |
| /** |
| * mei_other_client_is_connecting - checks if other |
| * client with the same client id is connected. |
| * |
| * @dev: the device structure |
| * @cl: private data of the file object |
| * |
| * returns 1 if other client is connected, 0 - otherwise. |
| */ |
| int mei_other_client_is_connecting(struct mei_device *dev, |
| struct mei_cl *cl) |
| { |
| struct mei_cl *cl_pos = NULL; |
| struct mei_cl *cl_next = NULL; |
| |
| list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) { |
| if ((cl_pos->state == MEI_FILE_CONNECTING) && |
| (cl_pos != cl) && |
| cl->me_client_id == cl_pos->me_client_id) |
| return 1; |
| |
| } |
| return 0; |
| } |
| |
| /** |
| * mei_disconnect - sends disconnect message to fw. |
| * |
| * @dev: the device structure |
| * @cl: private data of the file object |
| * |
| * This function returns -EIO on write failure |
| */ |
| int mei_disconnect(struct mei_device *dev, struct mei_cl *cl) |
| { |
| struct mei_msg_hdr *mei_hdr; |
| struct hbm_client_connect_request *req; |
| const size_t len = sizeof(struct hbm_client_connect_request); |
| |
| mei_hdr = mei_hbm_hdr(&dev->wr_msg_buf[0], len); |
| |
| req = (struct hbm_client_connect_request *)&dev->wr_msg_buf[1]; |
| memset(req, 0, len); |
| req->hbm_cmd = CLIENT_DISCONNECT_REQ_CMD; |
| req->host_addr = cl->host_client_id; |
| req->me_addr = cl->me_client_id; |
| req->reserved = 0; |
| |
| return mei_write_message(dev, mei_hdr, (unsigned char *)req, len); |
| } |
| |
| /** |
| * mei_connect - sends connect message to fw. |
| * |
| * @dev: the device structure |
| * @cl: private data of the file object |
| * |
| * This function returns -EIO on write failure |
| */ |
| int mei_connect(struct mei_device *dev, struct mei_cl *cl) |
| { |
| struct mei_msg_hdr *mei_hdr; |
| struct hbm_client_connect_request *req; |
| const size_t len = sizeof(struct hbm_client_connect_request); |
| |
| mei_hdr = mei_hbm_hdr(&dev->wr_msg_buf[0], len); |
| |
| req = (struct hbm_client_connect_request *) &dev->wr_msg_buf[1]; |
| req->hbm_cmd = CLIENT_CONNECT_REQ_CMD; |
| req->host_addr = cl->host_client_id; |
| req->me_addr = cl->me_client_id; |
| req->reserved = 0; |
| |
| return mei_write_message(dev, mei_hdr, (unsigned char *) req, len); |
| } |