1

/**

     2

    Network Driver for Beckhoff CCAT communication controller

     3

    Copyright (C) 2014  Beckhoff Automation GmbH

     4

    Author: Patrick Bruenn <p.bruenn@beckhoff.com>

     5

     6

    This program is free software; you can redistribute it and/or modify

     7

    it under the terms of the GNU General Public License as published by

     8

    the Free Software Foundation; either version 2 of the License, or

     9

    (at your option) any later version.

    10

    11

    This program is distributed in the hope that it will be useful,

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    but WITHOUT ANY WARRANTY; without even the implied warranty of

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    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

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    GNU General Public License for more details.

    15

    16

    You should have received a copy of the GNU General Public License along

    17

    with this program; if not, write to the Free Software Foundation, Inc.,

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    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

    19

*/

    20

    21

#include <linux/fs.h>

    22

#include <linux/kernel.h>

    23

#include <linux/module.h>

    24

#include <linux/sched.h>

    25

#include <linux/uaccess.h>

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#include "compat.h"

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#include "module.h"

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#include "print.h"

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#include "update.h"

    30

    31

#define CCAT_DATA_IN_4 0x038

    32

#define CCAT_DATA_IN_N 0x7F0

    33

#define CCAT_DATA_OUT_4 0x030

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#define CCAT_DATA_BLOCK_SIZE (size_t)((CCAT_DATA_IN_N - CCAT_DATA_IN_4)/8)

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#define CCAT_WRITE_BLOCK_SIZE 128

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#define CCAT_FLASH_SIZE (size_t)0xE0000

    37

    38

/**     FUNCTION_NAME            CMD,  CLOCKS          */

    39

#define CCAT_BULK_ERASE          0xE3, 8

    40

#define CCAT_GET_PROM_ID         0xD5, 40

    41

#define CCAT_READ_FLASH          0xC0, 32

    42

#define CCAT_READ_STATUS         0xA0, 16

    43

#define CCAT_WRITE_ENABLE        0x60, 8

    44

#define CCAT_WRITE_FLASH         0x40, 32

    45

    46

/* from http://graphics.stanford.edu/~seander/bithacks.html#ReverseByteWith32Bits */

    47

#define SWAP_BITS(B) \

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	((((B) * 0x0802LU & 0x22110LU) | ((B) * 0x8020LU & 0x88440LU)) * 0x10101LU >> 16)

    49

    50

/**

    51

 * struct update_buffer - keep track of a CCAT FPGA update

    52

 * @update: pointer to a valid ccat_update object

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 * @data: buffer used for write operations

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 * @size: number of bytes written to the data buffer, if 0 on ccat_update_release() no data will be written to FPGA

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 */

    56

struct update_buffer {

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	struct ccat_update *update;

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	char data[CCAT_FLASH_SIZE];

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	size_t size;

    60

};

    61

    62

static void ccat_wait_status_cleared(void __iomem * const ioaddr);

    63

static int ccat_read_flash(void __iomem * const ioaddr, char __user * buf,

    65

static void ccat_write_flash(const struct update_buffer *const buf);

    67

static void ccat_update_destroy(struct kref *ref);

    68

    69

/**

    70

 * wait_until_busy_reset() - wait until the busy flag was reset

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 * @ioaddr: address of the CCAT Update function in PCI config space

    72

 */

    73

static inline void wait_until_busy_reset(void __iomem * const ioaddr)

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{

    75

	wmb();

    76

	while (ioread8(ioaddr + 1)) {

    77

		schedule();

    78

	}

    79

}

    80

    81

static int ccat_update_open(struct inode *const i, struct file *const f)

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{

    83

	struct ccat_update *update =

    84

	    container_of(i->i_cdev, struct ccat_update, cdev);

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	struct update_buffer *buf;

    87

	kref_get(&update->refcount);

    88

	if (atomic_read(&update->refcount.refcount) > 2) {

    89

		kref_put(&update->refcount, ccat_update_destroy);

    90

		return -EBUSY;

    91

	}

    92

    93

	buf = kzalloc(sizeof(*buf), GFP_KERNEL);

    94

	if (!buf) {

    95

		kref_put(&update->refcount, ccat_update_destroy);

    96

		return -ENOMEM;

    97

	}

    98

    99

	buf->update = update;

   100

	f->private_data = buf;

   101

	return 0;

   102

}

   103

   104

static int ccat_update_release(struct inode *const i, struct file *const f)

   105

{

   106

	const struct update_buffer *const buf = f->private_data;

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	struct ccat_update *const update = buf->update;

   109

	if (buf->size > 0) {

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		ccat_update_cmd(update->ioaddr, CCAT_WRITE_ENABLE);

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		ccat_update_cmd(update->ioaddr, CCAT_BULK_ERASE);

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		ccat_wait_status_cleared(update->ioaddr);

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		ccat_write_flash(buf);

   114

	}

   115

	kfree(f->private_data);

   116

	kref_put(&update->refcount, ccat_update_destroy);

   117

	return 0;

   118

}

   119

   120

/**

   121

 * ccat_update_read() - Read CCAT configuration data from flash

   122

 * @f: file handle previously initialized with ccat_update_open()

   123

 * @buf: buffer in user space provided for our data

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 * @len: length of the user space buffer

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 * @off: current offset of our file operation

   126

 *

   127

 * Copies data from the CCAT FPGA's configuration flash to user space.

   128

 * Note that the size of the FPGA's firmware is not known exactly so it

   129

 * is very possible that the overall buffer ends with a lot of 0xff.

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 *

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 * Return: the number of bytes written, or 0 if EOF reached

   132

 */

   133

static ssize_t ccat_update_read(struct file *const f, char __user * buf,

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				size_t len, loff_t * off)

   135

{

   136

	struct update_buffer *update = f->private_data;

   138

	if (!buf || !off) {

   139

		return -EINVAL;

   140

	}

   141

	if (*off >= CCAT_FLASH_SIZE) {

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		return 0;

   143

	}

   144

	if (*off + len >= CCAT_FLASH_SIZE) {

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		len = CCAT_FLASH_SIZE - *off;

   146

	}

   147

	return ccat_read_flash(update->update->ioaddr, buf, len, off);

   148

}

   149

   150

/**

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 * ccat_update_write() - Write data to the CCAT FPGA's configuration flash

   152

 * @f: file handle previously initialized with ccat_update_open()

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 * @buf: buffer in user space providing the new configuration data (from *.rbf)

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 * @len: length of the user space buffer

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 * @off: current offset in the configuration data

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 *

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 * Copies data from user space (possibly a *.rbf) to the CCAT FPGA's

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 * configuration flash to user space.

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 *

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 * Return: the number of bytes written, or 0 if flash end is reached

   161

 */

   162

   163

static ssize_t ccat_update_write(struct file *const f, const char __user * buf,

   164

				 size_t len, loff_t * off)

   165

{

   166

	struct update_buffer *const update = f->private_data;

   168

	if (*off + len > sizeof(update->data))

   169

		return 0;

   170

   171

	if (copy_from_user(update->data + *off, buf, len)) {

   172

		return -EFAULT;

   173

	}

   174

   175

	*off += len;

   176

	update->size = *off;

   177

	return len;

   178

}

   179

   180

static struct file_operations update_ops = {

   181

	.owner = THIS_MODULE,

   182

	.open = ccat_update_open,

   183

	.release = ccat_update_release,

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	.read = ccat_update_read,

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	.write = ccat_update_write,

   186

};

   187

   188

/**

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 * __ccat_update_cmd() - Helper to issue a FPGA flash command

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 * @ioaddr: address of the CCAT Update function in PCI config space

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 * @cmd: the command identifier

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 * @clocks: the number of clocks associated with the specified command

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 *

   194

 * no write memory barrier is called and the busy flag is not evaluated

   195

 */

   198

{

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	iowrite8((0xff00 & clocks) >> 8, ioaddr);

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	iowrite8(0x00ff & clocks, ioaddr + 0x8);

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	iowrite8(cmd, ioaddr + 0x10);

   202

}

   203

   204

/**

   205

 * ccat_update_cmd() - Helper to issue a FPGA flash command

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 * @ioaddr: address of the CCAT Update function in PCI config space

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 * @cmd: the command identifier

   208

 * @clocks: the number of clocks associated with the specified command

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 *

   210

 * Triggers a full flash command cycle with write memory barrier and

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 * command activate. This call blocks until the busy flag is reset.

   212

 */

   215

{

   216

	__ccat_update_cmd(ioaddr, cmd, clocks);

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	wmb();

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	iowrite8(0xff, ioaddr + 0x7f8);

   219

	wait_until_busy_reset(ioaddr);

   220

}

   221

   222

/**

   223

 * ccat_update_cmd_addr() - Helper to issue a FPGA flash command with address parameter

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 * @ioaddr: address of the CCAT Update function in PCI config space

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 * @cmd: the command identifier

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 * @clocks: the number of clocks associated with the specified command

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 * @addr: 24 bit address associated with the specified command

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 *

   229

 * Triggers a full flash command cycle with write memory barrier and

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 * command activate. This call blocks until the busy flag is reset.

   231

 */

   232

static inline void ccat_update_cmd_addr(void __iomem * const ioaddr,

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	__ccat_update_cmd(ioaddr, cmd, clocks);

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	iowrite8(addr_2, ioaddr + 0x18);

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	iowrite8(addr_1, ioaddr + 0x20);

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	iowrite8(addr_0, ioaddr + 0x28);

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	wmb();

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	iowrite8(0xff, ioaddr + 0x7f8);

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	wait_until_busy_reset(ioaddr);

   246

}

   247

   248

/**

   249

 * ccat_get_prom_id() - Read CCAT PROM ID

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 * @ioaddr: address of the CCAT Update function in PCI config space

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 *

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 * Return: the CCAT FPGA's PROM identifier

   253

 */

   255

{

   256

	ccat_update_cmd(ioaddr, CCAT_GET_PROM_ID);

   257

	return ioread8(ioaddr + 0x38);

   258

}

   259

   260

/**

   261

 * ccat_get_status() - Read CCAT Update status

   262

 * @ioaddr: address of the CCAT Update function in PCI config space

   263

 *

   264

 * Return: the current status of the CCAT Update function

   265

 */

   267

{

   268

	ccat_update_cmd(ioaddr, CCAT_READ_STATUS);

   269

	return ioread8(ioaddr + 0x20);

   270

}

   271

   272

/**

   273

 * ccat_wait_status_cleared() - wait until CCAT status is cleared

   274

 * @ioaddr: address of the CCAT Update function in PCI config space

   275

 *

   276

 * Blocks until bit 7 of the CCAT Update status is reset

   277

 */

   278

static void ccat_wait_status_cleared(void __iomem * const ioaddr)

   279

{

   282

	do {

   283

		status = ccat_get_status(ioaddr);

   284

	} while (status & (1 << 7));

   285

}

   286

   287

/**

   288

 * ccat_read_flash_block() - Read a block of CCAT configuration data from flash

   289

 * @ioaddr: address of the CCAT Update function in PCI config space

   290

 * @addr: 24 bit address of the block to read

   291

 * @len: number of bytes to read from this block, len <= CCAT_DATA_BLOCK_SIZE

   292

 * @buf: output buffer in user space

   293

 *

   294

 * Copies one block of configuration data from the CCAT FPGA's flash to

   295

 * the user space buffer.

   296

 * Note that the size of the FPGA's firmware is not known exactly so it

   297

 * is very possible that the overall buffer ends with a lot of 0xff.

   298

 *

   299

 * Return: the number of bytes copied

   300

 */

   301

static int ccat_read_flash_block(void __iomem * const ioaddr,

   303

				 char __user * const buf)

   304

{

   308

	ccat_update_cmd_addr(ioaddr, CCAT_READ_FLASH + clocks, addr);

   309

	for (i = 0; i < len; i++) {

   310

		put_user(ioread8(ioaddr + CCAT_DATA_IN_4 + 8 * i), buf + i);

   311

	}

   312

	return len;

   313

}

   314

   315

/**

   316

 * ccat_read_flash() - Read a chunk of CCAT configuration data from flash

   317

 * @ioaddr: address of the CCAT Update function in PCI config space

   318

 * @buf: output buffer in user space

   319

 * @len: number of bytes to read

   320

 * @off: offset in the configuration data

   321

 *

   322

 * Copies multiple blocks of configuration data from the CCAT FPGA's

   323

 * flash to the user space buffer.

   324

 *

   325

 * Return: the number of bytes copied

   326

 */

   327

static int ccat_read_flash(void __iomem * const ioaddr, char __user * buf,

   329

{

   330

	const loff_t start = *off;

   332

	while (len > CCAT_DATA_BLOCK_SIZE) {

   333

		*off +=

   334

		    ccat_read_flash_block(ioaddr, *off, CCAT_DATA_BLOCK_SIZE,

   335

					  buf);

   336

		buf += CCAT_DATA_BLOCK_SIZE;

   337

		len -= CCAT_DATA_BLOCK_SIZE;

   338

	}

   339

	*off += ccat_read_flash_block(ioaddr, *off, len, buf);

   340

	return *off - start;

   341

}

   342

   343

/**

   344

 * ccat_write_flash_block() - Write a block of CCAT configuration data to flash

   345

 * @ioaddr: address of the CCAT Update function in PCI config space

   346

 * @addr: 24 bit start address in the CCAT FPGA's flash

   347

 * @len: number of bytes to write in this block, len <= CCAT_WRITE_BLOCK_SIZE

   348

 * @buf: input buffer

   349

 *

   350

 * Copies one block of configuration data to the CCAT FPGA's flash

   351

 *

   352

 * Return: the number of bytes copied

   353

 */

   354

static int ccat_write_flash_block(void __iomem * const ioaddr,

   356

				  const char *const buf)

   357

{

   361

	ccat_update_cmd(ioaddr, CCAT_WRITE_ENABLE);

   362

	for (i = 0; i < len; i++) {

   363

		iowrite8(buf[i], ioaddr + CCAT_DATA_OUT_4 + 8 * i);

   364

	}

   365

	ccat_update_cmd_addr(ioaddr, CCAT_WRITE_FLASH + clocks, addr);

   366

	ccat_wait_status_cleared(ioaddr);

   367

	return len;

   368

}

   369

   370

/**

   371

 * ccat_write_flash() - Write a new CCAT configuration to FPGA's flash

   372

 * @update: a CCAT Update buffer containing the new FPGA configuration

   373

 */

   374

static void ccat_write_flash(const struct update_buffer *const update)

   375

{

   376

	const char *buf = update->data;

   378

	size_t len = update->size;

   380

	while (len > CCAT_WRITE_BLOCK_SIZE) {

   381

		ccat_write_flash_block(update->update->ioaddr, off,

   383

		off += CCAT_WRITE_BLOCK_SIZE;

   384

		buf += CCAT_WRITE_BLOCK_SIZE;

   385

		len -= CCAT_WRITE_BLOCK_SIZE;

   386

	}

   388

}

   389

   390

/**

   391

 * ccat_update_init() - Initialize the CCAT Update function

   392

 */

   393

struct ccat_update *ccat_update_init(const struct ccat_device *const ccatdev,

   394

				     void __iomem * const addr)

   395

{

   396

	struct ccat_update *const update = kzalloc(sizeof(*update), GFP_KERNEL);

   398

	if (!update) {

   399

		return NULL;

   400

	}

   401

	kref_init(&update->refcount);

   402

	update->ioaddr = ccatdev->bar[0].ioaddr + ioread32(addr + 0x8);

   403

	memcpy_fromio(&update->info, addr, sizeof(update->info));

   404

	print_update_info(&update->info, update->ioaddr);

   405

   406

	if (0x00 != update->info.nRevision) {

   407

		pr_warn("CCAT Update rev. %d not supported\n",

   408

			update->info.nRevision);

   409

		goto cleanup;

   410

	}

   411

   412

	if (alloc_chrdev_region(&update->dev, 0, 1, KBUILD_MODNAME)) {

   413

		pr_warn("alloc_chrdev_region() failed\n");

   414

		goto cleanup;

   415

	}

   416

   417

	update->class = class_create(THIS_MODULE, "ccat_update");

   418

	if (NULL == update->class) {

   419

		pr_warn("Create device class failed\n");

   420

		goto cleanup;

   421

	}

   422

   423

	if (NULL ==

   424

	    device_create(update->class, NULL, update->dev, NULL,

   425

			  "ccat_update")) {

   426

		pr_warn("device_create() failed\n");

   427

		goto cleanup;

   428

	}

   429

   430

	cdev_init(&update->cdev, &update_ops);

   431

	update->cdev.owner = THIS_MODULE;

   432

	update->cdev.ops = &update_ops;

   433

	if (cdev_add(&update->cdev, update->dev, 1)) {

   434

		pr_warn("add update device failed\n");

   435

		goto cleanup;

   436

	}

   437

	return update;

   438

cleanup:

   439

	kref_put(&update->refcount, ccat_update_destroy);

   440

	return NULL;

   441

}

   442

   443

/**

   444

 * ccat_update_destroy() - Cleanup the CCAT Update function

   445

 * @ref: pointer to a struct kref embedded into a struct ccat_update, which we intend to destroy

   446

 *

   447

 * Retrieves the parent struct ccat_update and destroys it.

   448

 */

   449

static void ccat_update_destroy(struct kref *ref)

   450

{

   451

	struct ccat_update *update =

   452

	    container_of(ref, struct ccat_update, refcount);

   454

	cdev_del(&update->cdev);

   455

	device_destroy(update->class, update->dev);

   456

	class_destroy(update->class);

   457

	unregister_chrdev_region(update->dev, 1);

   458

	kfree(update);

   459

	pr_debug("%s(): done\n", __FUNCTION__);

   460

}

   461

   462

/**

   463

 * ccat_update_remove() - Prepare the CCAT Update function for removal

   464

 */

   465

void ccat_update_remove(struct ccat_update *update)

   466

{

   467

	kref_put(&update->refcount, ccat_update_destroy);

   468

	pr_debug("%s(): done\n", __FUNCTION__);

   469

}