misc: mic: add a bus driver for virtual MIC devices

This MIC virtual bus driver takes the responsibility of creating all
the virtual devices connected to the PCIe device on the host and the
platform device on the card. The MIC bus hardware operations provide
a way to abstract certain hardware details from the base physical devices.
Examples of devices added on the MIC virtual bus include host DMA and card DMA.
This abstraction enables using a common DMA driver on host and card.

Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Nikhil Rao <nikhil.rao@intel.com>
Signed-off-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Siva Yerramreddy <yshivakrishna@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 110 insertions, 0 deletions

diff --git a/include/linux/mic_bus.h b/include/linux/mic_bus.h
new file mode 100644
index 000000000000..d5b5f76d57ef
--- /dev/null
+++ b/include/linux/mic_bus.h
@@ -0,0 +1,110 @@
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2014 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 Bus driver.
+ *
+ * This implementation is very similar to the the virtio bus driver
+ * implementation @ include/linux/virtio.h.
+ */
+#ifndef _MIC_BUS_H_
+#define _MIC_BUS_H_
+/*
+ * Everything a mbus driver needs to work with any particular mbus
+ * implementation.
+ */
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+
+struct mbus_device_id {
+	__u32 device;
+	__u32 vendor;
+};
+
+#define MBUS_DEV_DMA_HOST 2
+#define MBUS_DEV_DMA_MIC 3
+#define MBUS_DEV_ANY_ID 0xffffffff
+
+/**
+ * mbus_device - representation of a device using mbus
+ * @mmio_va: virtual address of mmio space
+ * @hw_ops: the hardware ops supported by this device.
+ * @id: the device type identification (used to match it with a driver).
+ * @dev: underlying device.
+ * be used to communicate with.
+ * @index: unique position on the mbus bus
+ */
+struct mbus_device {
+	void __iomem *mmio_va;
+	struct mbus_hw_ops *hw_ops;
+	struct mbus_device_id id;
+	struct device dev;
+	int index;
+};
+
+/**
+ * mbus_driver - operations for a mbus I/O driver
+ * @driver: underlying device driver (populate name and owner).
+ * @id_table: the ids serviced by this driver.
+ * @probe: the function to call when a device is found.  Returns 0 or -errno.
+ * @remove: the function to call when a device is removed.
+ */
+struct mbus_driver {
+	struct device_driver driver;
+	const struct mbus_device_id *id_table;
+	int (*probe)(struct mbus_device *dev);
+	void (*scan)(struct mbus_device *dev);
+	void (*remove)(struct mbus_device *dev);
+};
+
+/**
+ * struct mic_irq - opaque pointer used as cookie
+ */
+struct mic_irq;
+
+/**
+ * mbus_hw_ops - Hardware operations for accessing a MIC device on the MIC bus.
+ */
+struct mbus_hw_ops {
+	struct mic_irq* (*request_threaded_irq)(struct mbus_device *mbdev,
+						irq_handler_t handler,
+						irq_handler_t thread_fn,
+						const char *name, void *data,
+						int intr_src);
+	void (*free_irq)(struct mbus_device *mbdev,
+			 struct mic_irq *cookie, void *data);
+	void (*ack_interrupt)(struct mbus_device *mbdev, int num);
+};
+
+struct mbus_device *
+mbus_register_device(struct device *pdev, int id, struct dma_map_ops *dma_ops,
+		     struct mbus_hw_ops *hw_ops, void __iomem *mmio_va);
+void mbus_unregister_device(struct mbus_device *mbdev);
+
+int mbus_register_driver(struct mbus_driver *drv);
+void mbus_unregister_driver(struct mbus_driver *drv);
+
+static inline struct mbus_device *dev_to_mbus(struct device *_dev)
+{
+	return container_of(_dev, struct mbus_device, dev);
+}
+
+static inline struct mbus_driver *drv_to_mbus(struct device_driver *drv)
+{
+	return container_of(drv, struct mbus_driver, driver);
+}
+
+#endif /* _MIC_BUS_H */