Intel MIC Host Driver, card OS state management.

This patch enables the following features:
a) Boots and shuts down the card via sysfs entries.
b) Allocates and maps a device page for communication with the
   card driver and updates the device page address via scratchpad
   registers.
c) Provides sysfs entries for shutdown status, kernel command line,
   ramdisk and log buffer information.

Co-author: Dasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Caz Yokoyama <Caz.Yokoyama@intel.com>
Signed-off-by: Dasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: Harshavardhan R Kharche <harshavardhan.r.kharche@intel.com>
Signed-off-by: Nikhil Rao <nikhil.rao@intel.com>
Signed-off-by: Sudeep Dutt <sudeep.dutt@intel.com>
Acked-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Reviewed-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 184 insertions, 0 deletions

diff --git a/drivers/misc/mic/host/mic_boot.c b/drivers/misc/mic/host/mic_boot.c
new file mode 100644
index 000000000000..936fc58084f3
--- /dev/null
+++ b/drivers/misc/mic/host/mic_boot.c
@@ -0,0 +1,184 @@
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2013 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Intel MIC Host driver.
+ *
+ */
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/interrupt.h>
+
+#include <linux/mic_common.h>
+#include "../common/mic_device.h"
+#include "mic_device.h"
+#include "mic_smpt.h"
+
+/**
+ * mic_reset - Reset the MIC device.
+ * @mdev: pointer to mic_device instance
+ */
+static void mic_reset(struct mic_device *mdev)
+{
+	int i;
+
+#define MIC_RESET_TO (45)
+
+	mdev->ops->reset_fw_ready(mdev);
+	mdev->ops->reset(mdev);
+
+	for (i = 0; i < MIC_RESET_TO; i++) {
+		if (mdev->ops->is_fw_ready(mdev))
+			return;
+		/*
+		 * Resets typically take 10s of seconds to complete.
+		 * Since an MMIO read is required to check if the
+		 * firmware is ready or not, a 1 second delay works nicely.
+		 */
+		msleep(1000);
+	}
+	mic_set_state(mdev, MIC_RESET_FAILED);
+}
+
+/* Initialize the MIC bootparams */
+void mic_bootparam_init(struct mic_device *mdev)
+{
+	struct mic_bootparam *bootparam = mdev->dp;
+
+	bootparam->magic = MIC_MAGIC;
+	bootparam->c2h_shutdown_db = mdev->shutdown_db;
+	bootparam->h2c_shutdown_db = -1;
+	bootparam->h2c_config_db = -1;
+	bootparam->shutdown_status = 0;
+	bootparam->shutdown_card = 0;
+}
+
+/**
+ * mic_start - Start the MIC.
+ * @mdev: pointer to mic_device instance
+ * @buf: buffer containing boot string including firmware/ramdisk path.
+ *
+ * This function prepares an MIC for boot and initiates boot.
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int mic_start(struct mic_device *mdev, const char *buf)
+{
+	int rc;
+	mutex_lock(&mdev->mic_mutex);
+retry:
+	if (MIC_OFFLINE != mdev->state) {
+		rc = -EINVAL;
+		goto unlock_ret;
+	}
+	if (!mdev->ops->is_fw_ready(mdev)) {
+		mic_reset(mdev);
+		/*
+		 * The state will either be MIC_OFFLINE if the reset succeeded
+		 * or MIC_RESET_FAILED if the firmware reset failed.
+		 */
+		goto retry;
+	}
+	rc = mdev->ops->load_mic_fw(mdev, buf);
+	if (rc)
+		goto unlock_ret;
+	mic_smpt_restore(mdev);
+	mic_intr_restore(mdev);
+	mdev->intr_ops->enable_interrupts(mdev);
+	mdev->ops->write_spad(mdev, MIC_DPLO_SPAD, mdev->dp_dma_addr);
+	mdev->ops->write_spad(mdev, MIC_DPHI_SPAD, mdev->dp_dma_addr >> 32);
+	mdev->ops->send_firmware_intr(mdev);
+	mic_set_state(mdev, MIC_ONLINE);
+unlock_ret:
+	mutex_unlock(&mdev->mic_mutex);
+	return rc;
+}
+
+/**
+ * mic_stop - Prepare the MIC for reset and trigger reset.
+ * @mdev: pointer to mic_device instance
+ * @force: force a MIC to reset even if it is already offline.
+ *
+ * RETURNS: None.
+ */
+void mic_stop(struct mic_device *mdev, bool force)
+{
+	mutex_lock(&mdev->mic_mutex);
+	if (MIC_OFFLINE != mdev->state || force) {
+		mic_bootparam_init(mdev);
+		mic_reset(mdev);
+		if (MIC_RESET_FAILED == mdev->state)
+			goto unlock;
+		mic_set_shutdown_status(mdev, MIC_NOP);
+		mic_set_state(mdev, MIC_OFFLINE);
+	}
+unlock:
+	mutex_unlock(&mdev->mic_mutex);
+}
+
+/**
+ * mic_shutdown - Initiate MIC shutdown.
+ * @mdev: pointer to mic_device instance
+ *
+ * RETURNS: None.
+ */
+void mic_shutdown(struct mic_device *mdev)
+{
+	struct mic_bootparam *bootparam = mdev->dp;
+	s8 db = bootparam->h2c_shutdown_db;
+
+	mutex_lock(&mdev->mic_mutex);
+	if (MIC_ONLINE == mdev->state && db != -1) {
+		bootparam->shutdown_card = 1;
+		mdev->ops->send_intr(mdev, db);
+		mic_set_state(mdev, MIC_SHUTTING_DOWN);
+	}
+	mutex_unlock(&mdev->mic_mutex);
+}
+
+/**
+ * mic_shutdown_work - Handle shutdown interrupt from MIC.
+ * @work: The work structure.
+ *
+ * This work is scheduled whenever the host has received a shutdown
+ * interrupt from the MIC.
+ */
+void mic_shutdown_work(struct work_struct *work)
+{
+	struct mic_device *mdev = container_of(work, struct mic_device,
+			shutdown_work);
+	struct mic_bootparam *bootparam = mdev->dp;
+
+	mutex_lock(&mdev->mic_mutex);
+	mic_set_shutdown_status(mdev, bootparam->shutdown_status);
+	bootparam->shutdown_status = 0;
+	if (MIC_SHUTTING_DOWN != mdev->state)
+		mic_set_state(mdev, MIC_SHUTTING_DOWN);
+	mutex_unlock(&mdev->mic_mutex);
+}
+
+/**
+ * mic_reset_trigger_work - Trigger MIC reset.
+ * @work: The work structure.
+ *
+ * This work is scheduled whenever the host wants to reset the MIC.
+ */
+void mic_reset_trigger_work(struct work_struct *work)
+{
+	struct mic_device *mdev = container_of(work, struct mic_device,
+			reset_trigger_work);
+
+	mic_stop(mdev, false);
+}