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-rw-r--r--drivers/misc/mei/interface.c428
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, &reg, 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));
+}