diff options
Diffstat (limited to 'drivers/misc/mei/interface.c')
| -rw-r--r-- | drivers/misc/mei/interface.c | 428 |
1 files changed, 428 insertions, 0 deletions
diff --git a/drivers/misc/mei/interface.c b/drivers/misc/mei/interface.c new file mode 100644 index 000000000000..428d21e36416 --- /dev/null +++ b/drivers/misc/mei/interface.c @@ -0,0 +1,428 @@ +/* + * + * 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); +} + +/** + * _host_get_filled_slots - gets number of device filled buffer slots + * + * @device: the device structure + * + * returns number of filled slots + */ +static unsigned char _host_get_filled_slots(const struct mei_device *dev) +{ + char read_ptr, write_ptr; + + 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_host_buffer_is_empty - checks if host buffer is empty. + * + * @dev: the device structure + * + * returns 1 if empty, 0 - otherwise. + */ +int mei_host_buffer_is_empty(struct mei_device *dev) +{ + unsigned char filled_slots; + + dev->host_hw_state = mei_hcsr_read(dev); + filled_slots = _host_get_filled_slots(dev); + + if (filled_slots == 0) + return 1; + + return 0; +} + +/** + * mei_count_empty_write_slots - counts write empty slots. + * + * @dev: the device structure + * + * returns -1(ESLOTS_OVERFLOW) if overflow, otherwise empty slots count + */ +int mei_count_empty_write_slots(struct mei_device *dev) +{ + unsigned char buffer_depth, filled_slots, empty_slots; + + dev->host_hw_state = mei_hcsr_read(dev); + buffer_depth = (unsigned char) ((dev->host_hw_state & H_CBD) >> 24); + filled_slots = _host_get_filled_slots(dev); + empty_slots = buffer_depth - filled_slots; + + /* check for overflow */ + if (filled_slots > buffer_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 *write_buffer, + unsigned long write_length) +{ + u32 temp_msg = 0; + unsigned long bytes_written = 0; + unsigned char buffer_depth, filled_slots, empty_slots; + unsigned long dw_to_write; + + dev->host_hw_state = mei_hcsr_read(dev); + + dev_dbg(&dev->pdev->dev, + "host_hw_state = 0x%08x.\n", + dev->host_hw_state); + + dev_dbg(&dev->pdev->dev, + "mei_write_message header=%08x.\n", + *((u32 *) header)); + + buffer_depth = (unsigned char) ((dev->host_hw_state & H_CBD) >> 24); + filled_slots = _host_get_filled_slots(dev); + empty_slots = buffer_depth - filled_slots; + dev_dbg(&dev->pdev->dev, + "filled = %hu, empty = %hu.\n", + filled_slots, empty_slots); + + dw_to_write = ((write_length + 3) / 4); + + if (dw_to_write > empty_slots) + return -EIO; + + mei_reg_write(dev, H_CB_WW, *((u32 *) header)); + + while (write_length >= 4) { + mei_reg_write(dev, H_CB_WW, + *(u32 *) (write_buffer + bytes_written)); + bytes_written += 4; + write_length -= 4; + } + + if (write_length > 0) { + memcpy(&temp_msg, &write_buffer[bytes_written], write_length); + mei_reg_write(dev, H_CB_WW, temp_msg); + } + + 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 *mei_flow_control; + + mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0]; + mei_hdr->host_addr = 0; + mei_hdr->me_addr = 0; + mei_hdr->length = sizeof(struct hbm_flow_control); + mei_hdr->msg_complete = 1; + mei_hdr->reserved = 0; + + mei_flow_control = (struct hbm_flow_control *) &dev->wr_msg_buf[1]; + memset(mei_flow_control, 0, sizeof(*mei_flow_control)); + mei_flow_control->host_addr = cl->host_client_id; + mei_flow_control->me_addr = cl->me_client_id; + mei_flow_control->hbm_cmd = MEI_FLOW_CONTROL_CMD; + memset(mei_flow_control->reserved, 0, + sizeof(mei_flow_control->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 *) mei_flow_control, + sizeof(struct hbm_flow_control)); +} + +/** + * 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_disconnect_request *mei_cli_disconnect; + + mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0]; + mei_hdr->host_addr = 0; + mei_hdr->me_addr = 0; + mei_hdr->length = sizeof(struct hbm_client_disconnect_request); + mei_hdr->msg_complete = 1; + mei_hdr->reserved = 0; + + mei_cli_disconnect = + (struct hbm_client_disconnect_request *) &dev->wr_msg_buf[1]; + memset(mei_cli_disconnect, 0, sizeof(*mei_cli_disconnect)); + mei_cli_disconnect->host_addr = cl->host_client_id; + mei_cli_disconnect->me_addr = cl->me_client_id; + mei_cli_disconnect->hbm_cmd = CLIENT_DISCONNECT_REQ_CMD; + mei_cli_disconnect->reserved[0] = 0; + + return mei_write_message(dev, mei_hdr, + (unsigned char *) mei_cli_disconnect, + sizeof(struct hbm_client_disconnect_request)); +} + +/** + * 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 *mei_cli_connect; + + mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0]; + mei_hdr->host_addr = 0; + mei_hdr->me_addr = 0; + mei_hdr->length = sizeof(struct hbm_client_connect_request); + mei_hdr->msg_complete = 1; + mei_hdr->reserved = 0; + + mei_cli_connect = + (struct hbm_client_connect_request *) &dev->wr_msg_buf[1]; + mei_cli_connect->host_addr = cl->host_client_id; + mei_cli_connect->me_addr = cl->me_client_id; + mei_cli_connect->hbm_cmd = CLIENT_CONNECT_REQ_CMD; + mei_cli_connect->reserved = 0; + + return mei_write_message(dev, mei_hdr, + (unsigned char *) mei_cli_connect, + sizeof(struct hbm_client_connect_request)); +} |
