/***************************************************************************** * * 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. * * (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/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/icap0 * * Note that unless foo.bit is an appropriately constructed partial * bitstream, this has a high likelihood of overwriting the design * currently programmed in the FPGA. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "xilinx_hwicap.h" #include "buffer_icap.h" #include "fifo_icap.h" #define DRIVER_NAME "icap" #define HWICAP_REGS (0x10000) #define XHWICAP_MAJOR 259 #define XHWICAP_MINOR 0 #define HWICAP_DEVICES 1 /* An array, which is set to true when the device is registered. */ static DEFINE_MUTEX(hwicap_mutex); static bool probed_devices[HWICAP_DEVICES]; static struct mutex icap_sem; static const struct class icap_class = { .name = "xilinx_config", }; #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, }; static const struct config_registers v6_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 = 22, .CTL_1 = 24, }; /** * hwicap_command_desync - Send a DESYNC command to the ICAP port. * @drvdata: a pointer to the drvdata. * * Returns: '0' on success and failure value on error * * 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. */ static 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 initiate 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. * @drvdata: a pointer to the drvdata. * @reg: a constant which represents the configuration * register value to be returned. * Examples: XHI_IDCODE, XHI_FLR. * @reg_data: returns the value of the register. * * Returns: '0' on success and failure value on error * * Sends a query packet to the ICAP and then receives the response. * The icap is left in Synched state. */ static int hwicap_get_configuration_register(struct hwicap_drvdata *drvdata, u32 reg, u32 *reg_data) { 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_NOOP_PACKET; buffer[index++] = XHI_SYNC_PACKET; buffer[index++] = XHI_NOOP_PACKET; buffer[index++] = XHI_NOOP_PACKET; /* * Write the data to the FIFO and initiate 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; /* If the syncword was not found, then we need to start over. */ status = drvdata->config->get_status(drvdata); if ((status & XHI_SR_DALIGN_MASK) != XHI_SR_DALIGN_MASK) return -EIO; index = 0; 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 initiate 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, reg_data, 1); if (status) return status; return 0; } static 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 __user *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; status = mutex_lock_interruptible(&drvdata->sem); if (status) return status; 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; memmove(drvdata->read_buffer, drvdata->read_buffer + bytes_to_read, 4 - bytes_to_read); } else { /* Get new data from the ICAP, and return what 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(drvdata->read_buffer, kbuf, bytes_remaining); drvdata->read_buffer_in_use = bytes_remaining; free_page((unsigned long)kbuf); } status = bytes_to_read; error: mutex_unlock(&drvdata->sem); return status; } static ssize_t hwicap_write(struct file *file, const char __user *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; status = mutex_lock_interruptible(&drvdata->sem); if (status) return status; 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: mutex_unlock(&drvdata->sem); return status; } static int hwicap_open(struct inode *inode, struct file *file) { struct hwicap_drvdata *drvdata; int status; mutex_lock(&hwicap_mutex); drvdata = container_of(inode->i_cdev, struct hwicap_drvdata, cdev); status = mutex_lock_interruptible(&drvdata->sem); if (status) goto out; 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: mutex_unlock(&drvdata->sem); out: mutex_unlock(&hwicap_mutex); return status; } static int hwicap_release(struct inode *inode, struct file *file) { struct hwicap_drvdata *drvdata = file->private_data; int i; int status = 0; mutex_lock(&drvdata->sem); 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; mutex_unlock(&drvdata->sem); return status; } static const struct file_operations hwicap_fops = { .owner = THIS_MODULE, .write = hwicap_write, .read = hwicap_read, .open = hwicap_open, .release = hwicap_release, .llseek = noop_llseek, }; static int hwicap_setup(struct platform_device *pdev, int id, const struct hwicap_driver_config *config, const struct config_registers *config_regs) { dev_t devt; struct hwicap_drvdata *drvdata = NULL; struct device *dev = &pdev->dev; int retval; dev_info(dev, "Xilinx icap port driver\n"); mutex_lock(&icap_sem); if (id < 0) { for (id = 0; id < HWICAP_DEVICES; id++) if (!probed_devices[id]) break; } if (id < 0 || id >= HWICAP_DEVICES) { mutex_unlock(&icap_sem); dev_err(dev, "%s%i too large\n", DRIVER_NAME, id); return -EINVAL; } if (probed_devices[id]) { mutex_unlock(&icap_sem); dev_err(dev, "cannot assign to %s%i; it is already in use\n", DRIVER_NAME, id); return -EBUSY; } probed_devices[id] = 1; mutex_unlock(&icap_sem); devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR + id); drvdata = devm_kzalloc(dev, sizeof(struct hwicap_drvdata), GFP_KERNEL); if (!drvdata) { retval = -ENOMEM; goto failed; } dev_set_drvdata(dev, drvdata); drvdata->base_address = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(drvdata->base_address)) { retval = PTR_ERR(drvdata->base_address); goto failed; } drvdata->devt = devt; drvdata->dev = dev; drvdata->config = config; drvdata->config_regs = config_regs; mutex_init(&drvdata->sem); drvdata->is_open = 0; 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 failed; } device_create(&icap_class, dev, devt, NULL, "%s%d", DRIVER_NAME, id); return 0; /* success */ failed: mutex_lock(&icap_sem); probed_devices[id] = 0; mutex_unlock(&icap_sem); return retval; } static struct hwicap_driver_config buffer_icap_config = { .get_configuration = buffer_icap_get_configuration, .set_configuration = buffer_icap_set_configuration, .get_status = buffer_icap_get_status, .reset = buffer_icap_reset, }; static struct hwicap_driver_config fifo_icap_config = { .get_configuration = fifo_icap_get_configuration, .set_configuration = fifo_icap_set_configuration, .get_status = fifo_icap_get_status, .reset = fifo_icap_reset, }; static int hwicap_drv_probe(struct platform_device *pdev) { const struct config_registers *regs; const struct hwicap_driver_config *config; const char *family; int id = -1; config = device_get_match_data(&pdev->dev); of_property_read_u32(pdev->dev.of_node, "port-number", &id); /* It's most likely that we're using V4, if the family is not * specified */ regs = &v4_config_registers; if (!of_property_read_string(pdev->dev.of_node, "xlnx,family", &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; else if (!strcmp(family, "virtex6")) regs = &v6_config_registers; } return hwicap_setup(pdev, id, config, regs); } static void hwicap_drv_remove(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct hwicap_drvdata *drvdata; drvdata = dev_get_drvdata(dev); device_destroy(&icap_class, drvdata->devt); cdev_del(&drvdata->cdev); mutex_lock(&icap_sem); probed_devices[MINOR(dev->devt)-XHWICAP_MINOR] = 0; mutex_unlock(&icap_sem); } /* Match table for device tree binding */ static const struct of_device_id 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 platform_driver hwicap_platform_driver = { .probe = hwicap_drv_probe, .remove = hwicap_drv_remove, .driver = { .name = DRIVER_NAME, .of_match_table = hwicap_of_match, }, }; static int __init hwicap_module_init(void) { dev_t devt; int retval; retval = class_register(&icap_class); if (retval) return retval; mutex_init(&icap_sem); devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR); retval = register_chrdev_region(devt, HWICAP_DEVICES, DRIVER_NAME); if (retval < 0) return retval; retval = platform_driver_register(&hwicap_platform_driver); if (retval) goto failed; return retval; failed: unregister_chrdev_region(devt, HWICAP_DEVICES); return retval; } static void __exit hwicap_module_cleanup(void) { dev_t devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR); class_unregister(&icap_class); platform_driver_unregister(&hwicap_platform_driver); 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");