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path: root/drivers/misc/mei/hw-me.c
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Diffstat (limited to 'drivers/misc/mei/hw-me.c')
-rw-r--r--drivers/misc/mei/hw-me.c576
1 files changed, 576 insertions, 0 deletions
diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
new file mode 100644
index 000000000000..45ea7185c003
--- /dev/null
+++ b/drivers/misc/mei/hw-me.c
@@ -0,0 +1,576 @@
+/*
+ *
+ * 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 <linux/kthread.h>
+#include <linux/interrupt.h>
+
+#include "mei_dev.h"
+#include "hw-me.h"
+
+#include "hbm.h"
+
+
+/**
+ * mei_reg_read - Reads 32bit data from the mei device
+ *
+ * @dev: the device structure
+ * @offset: offset from which to read the data
+ *
+ * returns register value (u32)
+ */
+static inline u32 mei_reg_read(const struct mei_me_hw *hw,
+ unsigned long offset)
+{
+ return ioread32(hw->mem_addr + offset);
+}
+
+
+/**
+ * mei_reg_write - Writes 32bit data to the mei device
+ *
+ * @dev: the device structure
+ * @offset: offset from which to write the data
+ * @value: register value to write (u32)
+ */
+static inline void mei_reg_write(const struct mei_me_hw *hw,
+ unsigned long offset, u32 value)
+{
+ iowrite32(value, hw->mem_addr + offset);
+}
+
+/**
+ * mei_mecbrw_read - Reads 32bit data from ME circular buffer
+ * read window register
+ *
+ * @dev: the device structure
+ *
+ * returns ME_CB_RW register value (u32)
+ */
+static u32 mei_me_mecbrw_read(const struct mei_device *dev)
+{
+ return mei_reg_read(to_me_hw(dev), ME_CB_RW);
+}
+/**
+ * mei_mecsr_read - Reads 32bit data from the ME CSR
+ *
+ * @dev: the device structure
+ *
+ * returns ME_CSR_HA register value (u32)
+ */
+static inline u32 mei_mecsr_read(const struct mei_me_hw *hw)
+{
+ return mei_reg_read(hw, ME_CSR_HA);
+}
+
+/**
+ * mei_hcsr_read - Reads 32bit data from the host CSR
+ *
+ * @dev: the device structure
+ *
+ * returns H_CSR register value (u32)
+ */
+static inline u32 mei_hcsr_read(const struct mei_me_hw *hw)
+{
+ return mei_reg_read(hw, H_CSR);
+}
+
+/**
+ * mei_hcsr_set - 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
+ */
+static inline void mei_hcsr_set(struct mei_me_hw *hw, u32 hcsr)
+{
+ hcsr &= ~H_IS;
+ mei_reg_write(hw, H_CSR, hcsr);
+}
+
+
+/**
+ * me_hw_config - configure hw dependent settings
+ *
+ * @dev: mei device
+ */
+static void mei_me_hw_config(struct mei_device *dev)
+{
+ u32 hcsr = mei_hcsr_read(to_me_hw(dev));
+ /* Doesn't change in runtime */
+ dev->hbuf_depth = (hcsr & H_CBD) >> 24;
+}
+/**
+ * mei_clear_interrupts - clear and stop interrupts
+ *
+ * @dev: the device structure
+ */
+static void mei_me_intr_clear(struct mei_device *dev)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ u32 hcsr = mei_hcsr_read(hw);
+ if ((hcsr & H_IS) == H_IS)
+ mei_reg_write(hw, H_CSR, hcsr);
+}
+/**
+ * mei_me_intr_enable - enables mei device interrupts
+ *
+ * @dev: the device structure
+ */
+static void mei_me_intr_enable(struct mei_device *dev)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ u32 hcsr = mei_hcsr_read(hw);
+ hcsr |= H_IE;
+ mei_hcsr_set(hw, hcsr);
+}
+
+/**
+ * mei_disable_interrupts - disables mei device interrupts
+ *
+ * @dev: the device structure
+ */
+static void mei_me_intr_disable(struct mei_device *dev)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ u32 hcsr = mei_hcsr_read(hw);
+ hcsr &= ~H_IE;
+ mei_hcsr_set(hw, hcsr);
+}
+
+/**
+ * mei_me_hw_reset - resets fw via mei csr register.
+ *
+ * @dev: the device structure
+ * @interrupts_enabled: if interrupt should be enabled after reset.
+ */
+static void mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ u32 hcsr = mei_hcsr_read(hw);
+
+ dev_dbg(&dev->pdev->dev, "before reset HCSR = 0x%08x.\n", hcsr);
+
+ hcsr |= (H_RST | H_IG);
+
+ if (intr_enable)
+ hcsr |= H_IE;
+ else
+ hcsr &= ~H_IE;
+
+ mei_hcsr_set(hw, hcsr);
+
+ hcsr = mei_hcsr_read(hw) | H_IG;
+ hcsr &= ~H_RST;
+
+ mei_hcsr_set(hw, hcsr);
+
+ hcsr = mei_hcsr_read(hw);
+
+ dev_dbg(&dev->pdev->dev, "current HCSR = 0x%08x.\n", hcsr);
+}
+
+/**
+ * mei_me_host_set_ready - enable device
+ *
+ * @dev - mei device
+ * returns bool
+ */
+
+static void mei_me_host_set_ready(struct mei_device *dev)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ hw->host_hw_state |= H_IE | H_IG | H_RDY;
+ mei_hcsr_set(hw, hw->host_hw_state);
+}
+/**
+ * mei_me_host_is_ready - check whether the host has turned ready
+ *
+ * @dev - mei device
+ * returns bool
+ */
+static bool mei_me_host_is_ready(struct mei_device *dev)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ hw->host_hw_state = mei_hcsr_read(hw);
+ return (hw->host_hw_state & H_RDY) == H_RDY;
+}
+
+/**
+ * mei_me_hw_is_ready - check whether the me(hw) has turned ready
+ *
+ * @dev - mei device
+ * returns bool
+ */
+static bool mei_me_hw_is_ready(struct mei_device *dev)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ hw->me_hw_state = mei_mecsr_read(hw);
+ return (hw->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA;
+}
+
+/**
+ * mei_hbuf_filled_slots - gets number of device filled buffer slots
+ *
+ * @dev: the device structure
+ *
+ * returns number of filled slots
+ */
+static unsigned char mei_hbuf_filled_slots(struct mei_device *dev)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ char read_ptr, write_ptr;
+
+ hw->host_hw_state = mei_hcsr_read(hw);
+
+ read_ptr = (char) ((hw->host_hw_state & H_CBRP) >> 8);
+ write_ptr = (char) ((hw->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.
+ */
+static bool mei_me_hbuf_is_empty(struct mei_device *dev)
+{
+ return mei_hbuf_filled_slots(dev) == 0;
+}
+
+/**
+ * mei_me_hbuf_empty_slots - counts write empty slots.
+ *
+ * @dev: the device structure
+ *
+ * returns -1(ESLOTS_OVERFLOW) if overflow, otherwise empty slots count
+ */
+static int mei_me_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;
+}
+
+static size_t mei_me_hbuf_max_len(const struct mei_device *dev)
+{
+ return dev->hbuf_depth * sizeof(u32) - sizeof(struct mei_msg_hdr);
+}
+
+
+/**
+ * mei_write_message - writes a message to mei device.
+ *
+ * @dev: the device structure
+ * @header: mei HECI header of message
+ * @buf: message payload will be written
+ *
+ * This function returns -EIO if write has failed
+ */
+static int mei_me_write_message(struct mei_device *dev,
+ struct mei_msg_hdr *header,
+ unsigned char *buf)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ unsigned long rem, dw_cnt;
+ unsigned long length = header->length;
+ u32 *reg_buf = (u32 *)buf;
+ u32 hcsr;
+ int i;
+ int empty_slots;
+
+ dev_dbg(&dev->pdev->dev, MEI_HDR_FMT, MEI_HDR_PRM(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(hw, H_CB_WW, *((u32 *) header));
+
+ for (i = 0; i < length / 4; i++)
+ mei_reg_write(hw, H_CB_WW, reg_buf[i]);
+
+ rem = length & 0x3;
+ if (rem > 0) {
+ u32 reg = 0;
+ memcpy(&reg, &buf[length - rem], rem);
+ mei_reg_write(hw, H_CB_WW, reg);
+ }
+
+ hcsr = mei_hcsr_read(hw) | H_IG;
+ mei_hcsr_set(hw, hcsr);
+ if (!mei_me_hw_is_ready(dev))
+ return -EIO;
+
+ return 0;
+}
+
+/**
+ * mei_me_count_full_read_slots - counts read full slots.
+ *
+ * @dev: the device structure
+ *
+ * returns -1(ESLOTS_OVERFLOW) if overflow, otherwise filled slots count
+ */
+static int mei_me_count_full_read_slots(struct mei_device *dev)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ char read_ptr, write_ptr;
+ unsigned char buffer_depth, filled_slots;
+
+ hw->me_hw_state = mei_mecsr_read(hw);
+ buffer_depth = (unsigned char)((hw->me_hw_state & ME_CBD_HRA) >> 24);
+ read_ptr = (char) ((hw->me_hw_state & ME_CBRP_HRA) >> 8);
+ write_ptr = (char) ((hw->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_me_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
+ */
+static int mei_me_read_slots(struct mei_device *dev, unsigned char *buffer,
+ unsigned long buffer_length)
+{
+ struct mei_me_hw *hw = to_me_hw(dev);
+ u32 *reg_buf = (u32 *)buffer;
+ u32 hcsr;
+
+ for (; buffer_length >= sizeof(u32); buffer_length -= sizeof(u32))
+ *reg_buf++ = mei_me_mecbrw_read(dev);
+
+ if (buffer_length > 0) {
+ u32 reg = mei_me_mecbrw_read(dev);
+ memcpy(reg_buf, &reg, buffer_length);
+ }
+
+ hcsr = mei_hcsr_read(hw) | H_IG;
+ mei_hcsr_set(hw, hcsr);
+ return 0;
+}
+
+/**
+ * mei_me_irq_quick_handler - The ISR of the MEI device
+ *
+ * @irq: The irq number
+ * @dev_id: pointer to the device structure
+ *
+ * returns irqreturn_t
+ */
+
+irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id)
+{
+ struct mei_device *dev = (struct mei_device *) dev_id;
+ struct mei_me_hw *hw = to_me_hw(dev);
+ u32 csr_reg = mei_hcsr_read(hw);
+
+ if ((csr_reg & H_IS) != H_IS)
+ return IRQ_NONE;
+
+ /* clear H_IS bit in H_CSR */
+ mei_reg_write(hw, H_CSR, csr_reg);
+
+ return IRQ_WAKE_THREAD;
+}
+
+/**
+ * mei_me_irq_thread_handler - function called after ISR to handle the interrupt
+ * processing.
+ *
+ * @irq: The irq number
+ * @dev_id: pointer to the device structure
+ *
+ * returns irqreturn_t
+ *
+ */
+irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id)
+{
+ struct mei_device *dev = (struct mei_device *) dev_id;
+ struct mei_cl_cb complete_list;
+ struct mei_cl_cb *cb_pos = NULL, *cb_next = NULL;
+ struct mei_cl *cl;
+ s32 slots;
+ int rets;
+ bool bus_message_received;
+
+
+ dev_dbg(&dev->pdev->dev, "function called after ISR to handle the interrupt processing.\n");
+ /* initialize our complete list */
+ mutex_lock(&dev->device_lock);
+ mei_io_list_init(&complete_list);
+
+ /* Ack the interrupt here
+ * In case of MSI we don't go through the quick handler */
+ if (pci_dev_msi_enabled(dev->pdev))
+ mei_clear_interrupts(dev);
+
+ /* check if ME wants a reset */
+ if (!mei_hw_is_ready(dev) &&
+ dev->dev_state != MEI_DEV_RESETING &&
+ dev->dev_state != MEI_DEV_INITIALIZING) {
+ dev_dbg(&dev->pdev->dev, "FW not ready.\n");
+ mei_reset(dev, 1);
+ mutex_unlock(&dev->device_lock);
+ return IRQ_HANDLED;
+ }
+
+ /* check if we need to start the dev */
+ if (!mei_host_is_ready(dev)) {
+ if (mei_hw_is_ready(dev)) {
+ dev_dbg(&dev->pdev->dev, "we need to start the dev.\n");
+
+ mei_host_set_ready(dev);
+
+ dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n");
+ /* link is established * start sending messages. */
+
+ dev->dev_state = MEI_DEV_INIT_CLIENTS;
+
+ mei_hbm_start_req(dev);
+ mutex_unlock(&dev->device_lock);
+ return IRQ_HANDLED;
+ } else {
+ dev_dbg(&dev->pdev->dev, "FW not ready.\n");
+ mutex_unlock(&dev->device_lock);
+ return IRQ_HANDLED;
+ }
+ }
+ /* check slots available for reading */
+ slots = mei_count_full_read_slots(dev);
+ while (slots > 0) {
+ /* we have urgent data to send so break the read */
+ if (dev->wr_ext_msg.hdr.length)
+ break;
+ dev_dbg(&dev->pdev->dev, "slots =%08x\n", slots);
+ dev_dbg(&dev->pdev->dev, "call mei_irq_read_handler.\n");
+ rets = mei_irq_read_handler(dev, &complete_list, &slots);
+ if (rets)
+ goto end;
+ }
+ rets = mei_irq_write_handler(dev, &complete_list);
+end:
+ dev_dbg(&dev->pdev->dev, "end of bottom half function.\n");
+ dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
+
+ bus_message_received = false;
+ if (dev->recvd_msg && waitqueue_active(&dev->wait_recvd_msg)) {
+ dev_dbg(&dev->pdev->dev, "received waiting bus message\n");
+ bus_message_received = true;
+ }
+ mutex_unlock(&dev->device_lock);
+ if (bus_message_received) {
+ dev_dbg(&dev->pdev->dev, "wake up dev->wait_recvd_msg\n");
+ wake_up_interruptible(&dev->wait_recvd_msg);
+ bus_message_received = false;
+ }
+ if (list_empty(&complete_list.list))
+ return IRQ_HANDLED;
+
+
+ list_for_each_entry_safe(cb_pos, cb_next, &complete_list.list, list) {
+ cl = cb_pos->cl;
+ list_del(&cb_pos->list);
+ if (cl) {
+ if (cl != &dev->iamthif_cl) {
+ dev_dbg(&dev->pdev->dev, "completing call back.\n");
+ mei_irq_complete_handler(cl, cb_pos);
+ cb_pos = NULL;
+ } else if (cl == &dev->iamthif_cl) {
+ mei_amthif_complete(dev, cb_pos);
+ }
+ }
+ }
+ return IRQ_HANDLED;
+}
+static const struct mei_hw_ops mei_me_hw_ops = {
+
+ .host_set_ready = mei_me_host_set_ready,
+ .host_is_ready = mei_me_host_is_ready,
+
+ .hw_is_ready = mei_me_hw_is_ready,
+ .hw_reset = mei_me_hw_reset,
+ .hw_config = mei_me_hw_config,
+
+ .intr_clear = mei_me_intr_clear,
+ .intr_enable = mei_me_intr_enable,
+ .intr_disable = mei_me_intr_disable,
+
+ .hbuf_free_slots = mei_me_hbuf_empty_slots,
+ .hbuf_is_ready = mei_me_hbuf_is_empty,
+ .hbuf_max_len = mei_me_hbuf_max_len,
+
+ .write = mei_me_write_message,
+
+ .rdbuf_full_slots = mei_me_count_full_read_slots,
+ .read_hdr = mei_me_mecbrw_read,
+ .read = mei_me_read_slots
+};
+
+/**
+ * init_mei_device - allocates and initializes the mei device structure
+ *
+ * @pdev: The pci device structure
+ *
+ * returns The mei_device_device pointer on success, NULL on failure.
+ */
+struct mei_device *mei_me_dev_init(struct pci_dev *pdev)
+{
+ struct mei_device *dev;
+
+ dev = kzalloc(sizeof(struct mei_device) +
+ sizeof(struct mei_me_hw), GFP_KERNEL);
+ if (!dev)
+ return NULL;
+
+ mei_device_init(dev);
+
+ INIT_LIST_HEAD(&dev->wd_cl.link);
+ INIT_LIST_HEAD(&dev->iamthif_cl.link);
+ mei_io_list_init(&dev->amthif_cmd_list);
+ mei_io_list_init(&dev->amthif_rd_complete_list);
+
+ INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
+ INIT_WORK(&dev->init_work, mei_host_client_init);
+
+ dev->ops = &mei_me_hw_ops;
+
+ dev->pdev = pdev;
+ return dev;
+}
+