[POWERPC] Xilinx: hwicap driver

This includes code for new fifo-based xps_hwicap in addition to the
older opb_hwicap, which has a significantly different interface.  The
common code between the two drivers is largely shared.

Significant differences exists between this driver and what is
supported in the EDK drivers.  In particular, most of the
architecture-specific code for reconfiguring individual FPGA resources
has been removed.  This functionality is likely better provided in a
user-space support library.  In addition, read and write access is
supported.  In addition, although the xps_hwicap cores support
interrupt-driver mode, this driver only supports polled operation, in
order to make the code simpler, and since the interrupt processing
overhead is likely to slow down the throughput under Linux.

Signed-off-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 904 insertions, 0 deletions

diff --git a/drivers/char/xilinx_hwicap/xilinx_hwicap.c b/drivers/char/xilinx_hwicap/xilinx_hwicap.c
new file mode 100644
index 000000000000..24f6aef0fd3c
--- /dev/null
+++ b/drivers/char/xilinx_hwicap/xilinx_hwicap.c
@@ -0,0 +1,904 @@
+/*****************************************************************************
+ *
+ *     Author: Xilinx, Inc.
+ *
+ *     This program is free software; you can redistribute it and/or modify it
+ *     under the terms of the GNU General Public License as published by the
+ *     Free Software Foundation; either version 2 of the License, or (at your
+ *     option) any later version.
+ *
+ *     XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS"
+ *     AS A COURTESY TO YOU, SOLELY FOR USE IN DEVELOPING PROGRAMS AND
+ *     SOLUTIONS FOR XILINX DEVICES.  BY PROVIDING THIS DESIGN, CODE,
+ *     OR INFORMATION AS ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE,
+ *     APPLICATION OR STANDARD, XILINX IS MAKING NO REPRESENTATION
+ *     THAT THIS IMPLEMENTATION IS FREE FROM ANY CLAIMS OF INFRINGEMENT,
+ *     AND YOU ARE RESPONSIBLE FOR OBTAINING ANY RIGHTS YOU MAY REQUIRE
+ *     FOR YOUR IMPLEMENTATION.  XILINX EXPRESSLY DISCLAIMS ANY
+ *     WARRANTY WHATSOEVER WITH RESPECT TO THE ADEQUACY OF THE
+ *     IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OR
+ *     REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE FROM CLAIMS OF
+ *     INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ *     FOR A PARTICULAR PURPOSE.
+ *
+ *     Xilinx products are not intended for use in life support appliances,
+ *     devices, or systems. Use in such applications is expressly prohibited.
+ *
+ *     (c) Copyright 2002 Xilinx Inc., Systems Engineering Group
+ *     (c) Copyright 2004 Xilinx Inc., Systems Engineering Group
+ *     (c) Copyright 2007-2008 Xilinx Inc.
+ *     All rights reserved.
+ *
+ *     You should have received a copy of the GNU General Public License along
+ *     with this program; if not, write to the Free Software Foundation, Inc.,
+ *     675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *****************************************************************************/
+
+/*
+ * This is the code behind /dev/xilinx_icap -- it allows a user-space
+ * application to use the Xilinx ICAP subsystem.
+ *
+ * The following operations are possible:
+ *
+ * open         open the port and initialize for access.
+ * release      release port
+ * write        Write a bitstream to the configuration processor.
+ * read         Read a data stream from the configuration processor.
+ *
+ * After being opened, the port is initialized and accessed to avoid a
+ * corrupted first read which may occur with some hardware.  The port
+ * is left in a desynched state, requiring that a synch sequence be
+ * transmitted before any valid configuration data.  A user will have
+ * exclusive access to the device while it remains open, and the state
+ * of the ICAP cannot be guaranteed after the device is closed.  Note
+ * that a complete reset of the core and the state of the ICAP cannot
+ * be performed on many versions of the cores, hence users of this
+ * device should avoid making inconsistent accesses to the device.  In
+ * particular, accessing the read interface, without first generating
+ * a write containing a readback packet can leave the ICAP in an
+ * inaccessible state.
+ *
+ * Note that in order to use the read interface, it is first necessary
+ * to write a request packet to the write interface.  i.e., it is not
+ * possible to simply readback the bitstream (or any configuration
+ * bits) from a device without specifically requesting them first.
+ * The code to craft such packets is intended to be part of the
+ * user-space application code that uses this device.  The simplest
+ * way to use this interface is simply:
+ *
+ * cp foo.bit /dev/xilinx_icap
+ *
+ * Note that unless foo.bit is an appropriately constructed partial
+ * bitstream, this has a high likelyhood of overwriting the design
+ * currently programmed in the FPGA.
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/fcntl.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/proc_fs.h>
+#include <asm/semaphore.h>
+#include <linux/sysctl.h>
+#include <linux/version.h>
+#include <linux/fs.h>
+#include <linux/cdev.h>
+#include <linux/platform_device.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+#ifdef CONFIG_OF
+/* For open firmware. */
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#endif
+
+#include "xilinx_hwicap.h"
+#include "buffer_icap.h"
+#include "fifo_icap.h"
+
+#define DRIVER_NAME "xilinx_icap"
+
+#define HWICAP_REGS   (0x10000)
+
+/* dynamically allocate device number */
+static int xhwicap_major;
+static int xhwicap_minor;
+#define HWICAP_DEVICES 1
+
+module_param(xhwicap_major, int, S_IRUGO);
+module_param(xhwicap_minor, int, S_IRUGO);
+
+/* An array, which is set to true when the device is registered. */
+static bool probed_devices[HWICAP_DEVICES];
+
+static struct class *icap_class;
+
+#define UNIMPLEMENTED 0xFFFF
+
+static const struct config_registers v2_config_registers = {
+        .CRC = 0,
+        .FAR = 1,
+        .FDRI = 2,
+        .FDRO = 3,
+        .CMD = 4,
+        .CTL = 5,
+        .MASK = 6,
+        .STAT = 7,
+        .LOUT = 8,
+        .COR = 9,
+        .MFWR = 10,
+        .FLR = 11,
+        .KEY = 12,
+        .CBC = 13,
+        .IDCODE = 14,
+        .AXSS = UNIMPLEMENTED,
+        .C0R_1 = UNIMPLEMENTED,
+        .CSOB = UNIMPLEMENTED,
+        .WBSTAR = UNIMPLEMENTED,
+        .TIMER = UNIMPLEMENTED,
+        .BOOTSTS = UNIMPLEMENTED,
+        .CTL_1 = UNIMPLEMENTED,
+};
+
+static const struct config_registers v4_config_registers = {
+        .CRC = 0,
+        .FAR = 1,
+        .FDRI = 2,
+        .FDRO = 3,
+        .CMD = 4,
+        .CTL = 5,
+        .MASK = 6,
+        .STAT = 7,
+        .LOUT = 8,
+        .COR = 9,
+        .MFWR = 10,
+        .FLR = UNIMPLEMENTED,
+        .KEY = UNIMPLEMENTED,
+        .CBC = 11,
+        .IDCODE = 12,
+        .AXSS = 13,
+        .C0R_1 = UNIMPLEMENTED,
+        .CSOB = UNIMPLEMENTED,
+        .WBSTAR = UNIMPLEMENTED,
+        .TIMER = UNIMPLEMENTED,
+        .BOOTSTS = UNIMPLEMENTED,
+        .CTL_1 = UNIMPLEMENTED,
+};
+static const struct config_registers v5_config_registers = {
+        .CRC = 0,
+        .FAR = 1,
+        .FDRI = 2,
+        .FDRO = 3,
+        .CMD = 4,
+        .CTL = 5,
+        .MASK = 6,
+        .STAT = 7,
+        .LOUT = 8,
+        .COR = 9,
+        .MFWR = 10,
+        .FLR = UNIMPLEMENTED,
+        .KEY = UNIMPLEMENTED,
+        .CBC = 11,
+        .IDCODE = 12,
+        .AXSS = 13,
+        .C0R_1 = 14,
+        .CSOB = 15,
+        .WBSTAR = 16,
+        .TIMER = 17,
+        .BOOTSTS = 18,
+        .CTL_1 = 19,
+};
+
+/**
+ * hwicap_command_desync: Send a DESYNC command to the ICAP port.
+ * @parameter drvdata: a pointer to the drvdata.
+ *
+ * This command desynchronizes the ICAP After this command, a
+ * bitstream containing a NULL packet, followed by a SYNCH packet is
+ * required before the ICAP will recognize commands.
+ */
+int hwicap_command_desync(struct hwicap_drvdata *drvdata)
+{
+        u32 buffer[4];
+        u32 index = 0;
+
+        /*
+         * Create the data to be written to the ICAP.
+         */
+        buffer[index++] = hwicap_type_1_write(drvdata->config_regs->CMD) | 1;
+        buffer[index++] = XHI_CMD_DESYNCH;
+        buffer[index++] = XHI_NOOP_PACKET;
+        buffer[index++] = XHI_NOOP_PACKET;
+
+        /*
+         * Write the data to the FIFO and intiate the transfer of data present
+         * in the FIFO to the ICAP device.
+         */
+        return drvdata->config->set_configuration(drvdata,
+                        &buffer[0], index);
+}
+
+/**
+ * hwicap_command_capture: Send a CAPTURE command to the ICAP port.
+ * @parameter drvdata: a pointer to the drvdata.
+ *
+ * This command captures all of the flip flop states so they will be
+ * available during readback.  One can use this command instead of
+ * enabling the CAPTURE block in the design.
+ */
+int hwicap_command_capture(struct hwicap_drvdata *drvdata)
+{
+        u32 buffer[7];
+        u32 index = 0;
+
+        /*
+         * Create the data to be written to the ICAP.
+         */
+        buffer[index++] = XHI_DUMMY_PACKET;
+        buffer[index++] = XHI_SYNC_PACKET;
+        buffer[index++] = XHI_NOOP_PACKET;
+        buffer[index++] = hwicap_type_1_write(drvdata->config_regs->CMD) | 1;
+        buffer[index++] = XHI_CMD_GCAPTURE;
+        buffer[index++] = XHI_DUMMY_PACKET;
+        buffer[index++] = XHI_DUMMY_PACKET;
+
+        /*
+         * Write the data to the FIFO and intiate the transfer of data
+         * present in the FIFO to the ICAP device.
+         */
+        return drvdata->config->set_configuration(drvdata,
+                        &buffer[0], index);
+
+}
+
+/**
+ * hwicap_get_configuration_register: Query a configuration register.
+ * @parameter drvdata: a pointer to the drvdata.
+ * @parameter reg: a constant which represents the configuration
+ *              register value to be returned.
+ *              Examples:  XHI_IDCODE, XHI_FLR.
+ * @parameter RegData: returns the value of the register.
+ *
+ * Sends a query packet to the ICAP and then receives the response.
+ * The icap is left in Synched state.
+ */
+int hwicap_get_configuration_register(struct hwicap_drvdata *drvdata,
+                u32 reg, u32 *RegData)
+{
+        int status;
+        u32 buffer[6];
+        u32 index = 0;
+
+        /*
+         * Create the data to be written to the ICAP.
+         */
+        buffer[index++] = XHI_DUMMY_PACKET;
+        buffer[index++] = XHI_SYNC_PACKET;
+        buffer[index++] = XHI_NOOP_PACKET;
+        buffer[index++] = hwicap_type_1_read(reg) | 1;
+        buffer[index++] = XHI_NOOP_PACKET;
+        buffer[index++] = XHI_NOOP_PACKET;
+
+        /*
+         * Write the data to the FIFO and intiate the transfer of data present
+         * in the FIFO to the ICAP device.
+         */
+        status = drvdata->config->set_configuration(drvdata,
+                        &buffer[0], index);
+        if (status)
+                return status;
+
+        /*
+         * Read the configuration register
+         */
+        status = drvdata->config->get_configuration(drvdata, RegData, 1);
+        if (status)
+                return status;
+
+        return 0;
+}
+
+int hwicap_initialize_hwicap(struct hwicap_drvdata *drvdata)
+{
+        int status;
+        u32 idcode;
+
+        dev_dbg(drvdata->dev, "initializing\n");
+
+        /* Abort any current transaction, to make sure we have the
+         * ICAP in a good state. */
+        dev_dbg(drvdata->dev, "Reset...\n");
+        drvdata->config->reset(drvdata);
+
+        dev_dbg(drvdata->dev, "Desync...\n");
+        status = hwicap_command_desync(drvdata);
+        if (status)
+                return status;
+
+        /* Attempt to read the IDCODE from ICAP.  This
+         * may not be returned correctly, due to the design of the
+         * hardware.
+         */
+        dev_dbg(drvdata->dev, "Reading IDCODE...\n");
+        status = hwicap_get_configuration_register(
+                        drvdata, drvdata->config_regs->IDCODE, &idcode);
+        dev_dbg(drvdata->dev, "IDCODE = %x\n", idcode);
+        if (status)
+                return status;
+
+        dev_dbg(drvdata->dev, "Desync...\n");
+        status = hwicap_command_desync(drvdata);
+        if (status)
+                return status;
+
+        return 0;
+}
+
+static ssize_t
+hwicap_read(struct file *file, char *buf, size_t count, loff_t *ppos)
+{
+        struct hwicap_drvdata *drvdata = file->private_data;
+        ssize_t bytes_to_read = 0;
+        u32 *kbuf;
+        u32 words;
+        u32 bytes_remaining;
+        int status;
+
+        if (down_interruptible(&drvdata->sem))
+                return -ERESTARTSYS;
+
+        if (drvdata->read_buffer_in_use) {
+                /* If there are leftover bytes in the buffer, just */
+                /* return them and don't try to read more from the */
+                /* ICAP device. */
+                bytes_to_read =
+                        (count < drvdata->read_buffer_in_use) ? count :
+                        drvdata->read_buffer_in_use;
+
+                /* Return the data currently in the read buffer. */
+                if (copy_to_user(buf, drvdata->read_buffer, bytes_to_read)) {
+                        status = -EFAULT;
+                        goto error;
+                }
+                drvdata->read_buffer_in_use -= bytes_to_read;
+                memcpy(drvdata->read_buffer + bytes_to_read,
+                                drvdata->read_buffer, 4 - bytes_to_read);
+        } else {
+                /* Get new data from the ICAP, and return was was requested. */
+                kbuf = (u32 *) get_zeroed_page(GFP_KERNEL);
+                if (!kbuf) {
+                        status = -ENOMEM;
+                        goto error;
+                }
+
+                /* The ICAP device is only able to read complete */
+                /* words.  If a number of bytes that do not correspond */
+                /* to complete words is requested, then we read enough */
+                /* words to get the required number of bytes, and then */
+                /* save the remaining bytes for the next read. */
+
+                /* Determine the number of words to read, rounding up */
+                /* if necessary. */
+                words = ((count + 3) >> 2);
+                bytes_to_read = words << 2;
+
+                if (bytes_to_read > PAGE_SIZE)
+                        bytes_to_read = PAGE_SIZE;
+
+                /* Ensure we only read a complete number of words. */
+                bytes_remaining = bytes_to_read & 3;
+                bytes_to_read &= ~3;
+                words = bytes_to_read >> 2;
+
+                status = drvdata->config->get_configuration(drvdata,
+                                kbuf, words);
+
+                /* If we didn't read correctly, then bail out. */
+                if (status) {
+                        free_page((unsigned long)kbuf);
+                        goto error;
+                }
+
+                /* If we fail to return the data to the user, then bail out. */
+                if (copy_to_user(buf, kbuf, bytes_to_read)) {
+                        free_page((unsigned long)kbuf);
+                        status = -EFAULT;
+                        goto error;
+                }
+                memcpy(kbuf, drvdata->read_buffer, bytes_remaining);
+                drvdata->read_buffer_in_use = bytes_remaining;
+                free_page((unsigned long)kbuf);
+        }
+        status = bytes_to_read;
+ error:
+        up(&drvdata->sem);
+        return status;
+}
+
+static ssize_t
+hwicap_write(struct file *file, const char *buf,
+                size_t count, loff_t *ppos)
+{
+        struct hwicap_drvdata *drvdata = file->private_data;
+        ssize_t written = 0;
+        ssize_t left = count;
+        u32 *kbuf;
+        ssize_t len;
+        ssize_t status;
+
+        if (down_interruptible(&drvdata->sem))
+                return -ERESTARTSYS;
+
+        left += drvdata->write_buffer_in_use;
+
+        /* Only write multiples of 4 bytes. */
+        if (left < 4) {
+                status = 0;
+                goto error;
+        }
+
+        kbuf = (u32 *) __get_free_page(GFP_KERNEL);
+        if (!kbuf) {
+                status = -ENOMEM;
+                goto error;
+        }
+
+        while (left > 3) {
+                /* only write multiples of 4 bytes, so there might */
+                /* be as many as 3 bytes left (at the end). */
+                len = left;
+
+                if (len > PAGE_SIZE)
+                        len = PAGE_SIZE;
+                len &= ~3;
+
+                if (drvdata->write_buffer_in_use) {
+                        memcpy(kbuf, drvdata->write_buffer,
+                                        drvdata->write_buffer_in_use);
+                        if (copy_from_user(
+                            (((char *)kbuf) + (drvdata->write_buffer_in_use)),
+                            buf + written,
+                            len - (drvdata->write_buffer_in_use))) {
+                                free_page((unsigned long)kbuf);
+                                status = -EFAULT;
+                                goto error;
+                        }
+                } else {
+                        if (copy_from_user(kbuf, buf + written, len)) {
+                                free_page((unsigned long)kbuf);
+                                status = -EFAULT;
+                                goto error;
+                        }
+                }
+
+                status = drvdata->config->set_configuration(drvdata,
+                                kbuf, len >> 2);
+
+                if (status) {
+                        free_page((unsigned long)kbuf);
+                        status = -EFAULT;
+                        goto error;
+                }
+                if (drvdata->write_buffer_in_use) {
+                        len -= drvdata->write_buffer_in_use;
+                        left -= drvdata->write_buffer_in_use;
+                        drvdata->write_buffer_in_use = 0;
+                }
+                written += len;
+                left -= len;
+        }
+        if ((left > 0) && (left < 4)) {
+                if (!copy_from_user(drvdata->write_buffer,
+                                                buf + written, left)) {
+                        drvdata->write_buffer_in_use = left;
+                        written += left;
+                        left = 0;
+                }
+        }
+
+        free_page((unsigned long)kbuf);
+        status = written;
+ error:
+        up(&drvdata->sem);
+        return status;
+}
+
+static int hwicap_open(struct inode *inode, struct file *file)
+{
+        struct hwicap_drvdata *drvdata;
+        int status;
+
+        drvdata = container_of(inode->i_cdev, struct hwicap_drvdata, cdev);
+
+        if (down_interruptible(&drvdata->sem))
+                return -ERESTARTSYS;
+
+        if (drvdata->is_open) {
+                status = -EBUSY;
+                goto error;
+        }
+
+        status = hwicap_initialize_hwicap(drvdata);
+        if (status) {
+                dev_err(drvdata->dev, "Failed to open file");
+                goto error;
+        }
+
+        file->private_data = drvdata;
+        drvdata->write_buffer_in_use = 0;
+        drvdata->read_buffer_in_use = 0;
+        drvdata->is_open = 1;
+
+ error:
+        up(&drvdata->sem);
+        return status;
+}
+
+static int hwicap_release(struct inode *inode, struct file *file)
+{
+        struct hwicap_drvdata *drvdata = file->private_data;
+        int i;
+        int status = 0;
+
+        if (down_interruptible(&drvdata->sem))
+                return -ERESTARTSYS;
+
+        if (drvdata->write_buffer_in_use) {
+                /* Flush write buffer. */
+                for (i = drvdata->write_buffer_in_use; i < 4; i++)
+                        drvdata->write_buffer[i] = 0;
+
+                status = drvdata->config->set_configuration(drvdata,
+                                (u32 *) drvdata->write_buffer, 1);
+                if (status)
+                        goto error;
+        }
+
+        status = hwicap_command_desync(drvdata);
+        if (status)
+                goto error;
+
+ error:
+        drvdata->is_open = 0;
+        up(&drvdata->sem);
+        return status;
+}
+
+static struct file_operations hwicap_fops = {
+        .owner = THIS_MODULE,
+        .write = hwicap_write,
+        .read = hwicap_read,
+        .open = hwicap_open,
+        .release = hwicap_release,
+};
+
+static int __devinit hwicap_setup(struct device *dev, int id,
+                const struct resource *regs_res,
+                const struct hwicap_driver_config *config,
+                const struct config_registers *config_regs)
+{
+        dev_t devt;
+        struct hwicap_drvdata *drvdata = NULL;
+        int retval = 0;
+
+        dev_info(dev, "Xilinx icap port driver\n");
+
+        if (id < 0) {
+                for (id = 0; id < HWICAP_DEVICES; id++)
+                        if (!probed_devices[id])
+                                break;
+        }
+        if (id < 0 || id >= HWICAP_DEVICES) {
+                dev_err(dev, "%s%i too large\n", DRIVER_NAME, id);
+                return -EINVAL;
+        }
+        if (probed_devices[id]) {
+                dev_err(dev, "cannot assign to %s%i; it is already in use\n",
+                        DRIVER_NAME, id);
+                return -EBUSY;
+        }
+
+        probed_devices[id] = 1;
+
+        devt = MKDEV(xhwicap_major, xhwicap_minor + id);
+
+        drvdata = kmalloc(sizeof(struct hwicap_drvdata), GFP_KERNEL);
+        if (!drvdata) {
+                dev_err(dev, "Couldn't allocate device private record\n");
+                return -ENOMEM;
+        }
+        memset((void *)drvdata, 0, sizeof(struct hwicap_drvdata));
+        dev_set_drvdata(dev, (void *)drvdata);
+
+        if (!regs_res) {
+                dev_err(dev, "Couldn't get registers resource\n");
+                retval = -EFAULT;
+                goto failed1;
+        }
+
+        drvdata->mem_start = regs_res->start;
+        drvdata->mem_end = regs_res->end;
+        drvdata->mem_size = regs_res->end - regs_res->start + 1;
+
+        if (!request_mem_region(drvdata->mem_start,
+                                        drvdata->mem_size, DRIVER_NAME)) {
+                dev_err(dev, "Couldn't lock memory region at %p\n",
+                        (void *)regs_res->start);
+                retval = -EBUSY;
+                goto failed1;
+        }
+
+        drvdata->devt = devt;
+        drvdata->dev = dev;
+        drvdata->base_address = ioremap(drvdata->mem_start, drvdata->mem_size);
+        if (!drvdata->base_address) {
+                dev_err(dev, "ioremap() failed\n");
+                goto failed2;
+        }
+
+        drvdata->config = config;
+        drvdata->config_regs = config_regs;
+
+        init_MUTEX(&drvdata->sem);
+        drvdata->is_open = 0;
+
+        dev_info(dev, "ioremap %lx to %p with size %x\n",
+                 (unsigned long int)drvdata->mem_start,
+                        drvdata->base_address, drvdata->mem_size);
+
+        cdev_init(&drvdata->cdev, &hwicap_fops);
+        drvdata->cdev.owner = THIS_MODULE;
+        retval = cdev_add(&drvdata->cdev, devt, 1);
+        if (retval) {
+                dev_err(dev, "cdev_add() failed\n");
+                goto failed3;
+        }
+        /*  devfs_mk_cdev(devt, S_IFCHR|S_IRUGO|S_IWUGO, DRIVER_NAME); */
+        class_device_create(icap_class, NULL, devt, NULL, DRIVER_NAME);
+        return 0;               /* success */
+
+ failed3:
+        iounmap(drvdata->base_address);
+
+ failed2:
+        release_mem_region(regs_res->start, drvdata->mem_size);
+
+ failed1:
+        kfree(drvdata);
+
+        return retval;
+}
+
+static struct hwicap_driver_config buffer_icap_config = {
+        .get_configuration = buffer_icap_get_configuration,
+        .set_configuration = buffer_icap_set_configuration,
+        .reset = buffer_icap_reset,
+};
+
+static struct hwicap_driver_config fifo_icap_config = {
+        .get_configuration = fifo_icap_get_configuration,
+        .set_configuration = fifo_icap_set_configuration,
+        .reset = fifo_icap_reset,
+};
+
+static int __devexit hwicap_remove(struct device *dev)
+{
+        struct hwicap_drvdata *drvdata;
+
+        drvdata = (struct hwicap_drvdata *)dev_get_drvdata(dev);
+
+        if (!drvdata)
+                return 0;
+
+        class_device_destroy(icap_class, drvdata->devt);
+        cdev_del(&drvdata->cdev);
+        iounmap(drvdata->base_address);
+        release_mem_region(drvdata->mem_start, drvdata->mem_size);
+        kfree(drvdata);
+        dev_set_drvdata(dev, NULL);
+        probed_devices[MINOR(dev->devt)-xhwicap_minor] = 0;
+
+        return 0;               /* success */
+}
+
+static int __devinit hwicap_drv_probe(struct platform_device *pdev)
+{
+        struct resource *res;
+        const struct config_registers *regs;
+        const char *family;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res)
+                return -ENODEV;
+
+        /* It's most likely that we're using V4, if the family is not
+           specified */
+        regs = &v4_config_registers;
+        family = pdev->dev.platform_data;
+
+        if (family) {
+                if (!strcmp(family, "virtex2p")) {
+                        regs = &v2_config_registers;
+                } else if (!strcmp(family, "virtex4")) {
+                        regs = &v4_config_registers;
+                } else if (!strcmp(family, "virtex5")) {
+                        regs = &v5_config_registers;
+                }
+        }
+
+        return hwicap_setup(&pdev->dev, pdev->id, res,
+                        &buffer_icap_config, regs);
+}
+
+static int __devexit hwicap_drv_remove(struct platform_device *pdev)
+{
+        return hwicap_remove(&pdev->dev);
+}
+
+static struct platform_driver hwicap_platform_driver = {
+        .probe = hwicap_drv_probe,
+        .remove = hwicap_drv_remove,
+        .driver = {
+                .owner = THIS_MODULE,
+                .name = DRIVER_NAME,
+        },
+};
+
+/* ---------------------------------------------------------------------
+ * OF bus binding
+ */
+
+#if defined(CONFIG_OF)
+static int __devinit
+hwicap_of_probe(struct of_device *op, const struct of_device_id *match)
+{
+        struct resource res;
+        const unsigned int *id;
+        const char *family;
+        int rc;
+        const struct hwicap_driver_config *config = match->data;
+        const struct config_registers *regs;
+
+        dev_dbg(&op->dev, "hwicap_of_probe(%p, %p)\n", op, match);
+
+        rc = of_address_to_resource(op->node, 0, &res);
+        if (rc) {
+                dev_err(&op->dev, "invalid address\n");
+                return rc;
+        }
+
+        id = of_get_property(op->node, "port-number", NULL);
+
+        /* It's most likely that we're using V4, if the family is not
+           specified */
+        regs = &v4_config_registers;
+        family = of_get_property(op->node, "xlnx,family", NULL);
+
+        if (family) {
+                if (!strcmp(family, "virtex2p")) {
+                        regs = &v2_config_registers;
+                } else if (!strcmp(family, "virtex4")) {
+                        regs = &v4_config_registers;
+                } else if (!strcmp(family, "virtex5")) {
+                        regs = &v5_config_registers;
+                }
+        }
+        return hwicap_setup(&op->dev, id ? *id : -1, &res, config,
+                        regs);
+}
+
+static int __devexit hwicap_of_remove(struct of_device *op)
+{
+        return hwicap_remove(&op->dev);
+}
+
+/* Match table for of_platform binding */
+static const struct of_device_id __devinit hwicap_of_match[] = {
+        { .compatible = "xlnx,opb-hwicap-1.00.b", .data = &buffer_icap_config},
+        { .compatible = "xlnx,xps-hwicap-1.00.a", .data = &fifo_icap_config},
+        {},
+};
+MODULE_DEVICE_TABLE(of, hwicap_of_match);
+
+static struct of_platform_driver hwicap_of_driver = {
+        .owner = THIS_MODULE,
+        .name = DRIVER_NAME,
+        .match_table = hwicap_of_match,
+        .probe = hwicap_of_probe,
+        .remove = __devexit_p(hwicap_of_remove),
+        .driver = {
+                .name = DRIVER_NAME,
+        },
+};
+
+/* Registration helpers to keep the number of #ifdefs to a minimum */
+static inline int __devinit hwicap_of_register(void)
+{
+        pr_debug("hwicap: calling of_register_platform_driver()\n");
+        return of_register_platform_driver(&hwicap_of_driver);
+}
+
+static inline void __devexit hwicap_of_unregister(void)
+{
+        of_unregister_platform_driver(&hwicap_of_driver);
+}
+#else /* CONFIG_OF */
+/* CONFIG_OF not enabled; do nothing helpers */
+static inline int __devinit hwicap_of_register(void) { return 0; }
+static inline void __devexit hwicap_of_unregister(void) { }
+#endif /* CONFIG_OF */
+
+static int __devinit hwicap_module_init(void)
+{
+        dev_t devt;
+        int retval;
+
+        icap_class = class_create(THIS_MODULE, "xilinx_config");
+
+        if (xhwicap_major) {
+                devt = MKDEV(xhwicap_major, xhwicap_minor);
+                retval = register_chrdev_region(
+                                devt,
+                                HWICAP_DEVICES,
+                                DRIVER_NAME);
+                if (retval < 0)
+                        return retval;
+        } else {
+                retval = alloc_chrdev_region(&devt,
+                                xhwicap_minor,
+                                HWICAP_DEVICES,
+                                DRIVER_NAME);
+                if (retval < 0)
+                        return retval;
+                xhwicap_major = MAJOR(devt);
+        }
+
+        retval = platform_driver_register(&hwicap_platform_driver);
+
+        if (retval)
+                goto failed1;
+
+        retval = hwicap_of_register();
+
+        if (retval)
+                goto failed2;
+
+        return retval;
+
+ failed2:
+        platform_driver_unregister(&hwicap_platform_driver);
+
+ failed1:
+        unregister_chrdev_region(devt, HWICAP_DEVICES);
+
+        return retval;
+}
+
+static void __devexit hwicap_module_cleanup(void)
+{
+        dev_t devt = MKDEV(xhwicap_major, xhwicap_minor);
+
+        class_destroy(icap_class);
+
+        platform_driver_unregister(&hwicap_platform_driver);
+
+        hwicap_of_unregister();
+
+        unregister_chrdev_region(devt, HWICAP_DEVICES);
+}
+
+module_init(hwicap_module_init);
+module_exit(hwicap_module_cleanup);
+
+MODULE_AUTHOR("Xilinx, Inc; Xilinx Research Labs Group");
+MODULE_DESCRIPTION("Xilinx ICAP Port Driver");
+MODULE_LICENSE("GPL");