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,

    12

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    13

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    14

    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.,

    18

    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>

    26

#include "compat.h"

    27

#include "module.h"

    28

#include "print.h"

    29

#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

    34

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

    35

#define CCAT_WRITE_BLOCK_SIZE 128

    36

#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

    55

 */

    56

struct update_buffer {

    57

	struct ccat_update *update;

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	char data[CCAT_FLASH_SIZE];

    59

	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,

    64

			   uint32_t len, loff_t * off);

    65

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

    66

static void ccat_update_cmd(void __iomem * const ioaddr, uint8_t cmd,

    67

			    uint16_t clocks);

    68

static void ccat_update_destroy(struct kref *ref);

    69

    70

/**

    71

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

    72

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

    73

 */

    74

static inline void wait_until_busy_reset(void __iomem * const ioaddr)

    75

{

    76

	wmb();

    77

	while (ioread8(ioaddr + 1)) {

    78

		schedule();

    79

	}

    80

}

    81

    82

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

    83

{

    84

	struct ccat_update *update =

    85

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

    86

	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;

   107

	struct ccat_update *const update = buf->update;

   108

	if (buf->size > 0) {

   109

		ccat_update_cmd(update->ioaddr, CCAT_WRITE_ENABLE);

   110

		ccat_update_cmd(update->ioaddr, CCAT_BULK_ERASE);

   111

		ccat_wait_status_cleared(update->ioaddr);

   112

		ccat_write_flash(buf);

   113

	}

   114

	kfree(f->private_data);

   115

	kref_put(&update->refcount, ccat_update_destroy);

   116

	return 0;

   117

}

   118

   119

/**

   120

 * ccat_update_read() - Read CCAT configuration data from flash

   121

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

   122

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

   123

 * @len: length of the user space buffer

   124

 * @off: current offset of our file operation

   125

 *

   126

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

   127

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

   128

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

   129

 *

   130

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

   131

 */

   132

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

   133

				size_t len, loff_t * off)

   134

{

   135

	struct update_buffer *update = f->private_data;

   136

	if (!buf || !off) {

   137

		return -EINVAL;

   138

	}

   139

	if (*off >= CCAT_FLASH_SIZE) {

   140

		return 0;

   141

	}

   142

	if (*off + len >= CCAT_FLASH_SIZE) {

   143

		len = CCAT_FLASH_SIZE - *off;

   144

	}

   145

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

   146

}

   147

   148

/**

   149

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

   150

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

   151

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

   152

 * @len: length of the user space buffer

   153

 * @off: current offset in the configuration data

   154

 *

   155

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

   156

 * configuration flash to user space.

   157

 *

   158

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

   159

 */

   160

   161

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

   162

				 size_t len, loff_t * off)

   163

{

   164

	struct update_buffer *const update = f->private_data;

   165

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

   166

		return 0;

   167

   172

	*off += len;

   173

	update->size = *off;

   174

	return len;

   175

}

   176

   177

static struct file_operations update_ops = {

   178

	.owner = THIS_MODULE,

   179

	.open = ccat_update_open,

   180

	.release = ccat_update_release,

   181

	.read = ccat_update_read,

   182

	.write = ccat_update_write,

   183

};

   184

   185

/**

   186

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

   187

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

   188

 * @cmd: the command identifier

   189

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

   190

 *

   191

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

   192

 */

   193

static inline void __ccat_update_cmd(void __iomem * const ioaddr, uint8_t cmd,

   194

				     uint16_t clocks)

   195

{

   196

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

   197

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

   198

	iowrite8(cmd, ioaddr + 0x10);

   199

}

   200

   201

/**

   202

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

   203

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

   204

 * @cmd: the command identifier

   205

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

   206

 *

   207

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

   208

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

   209

 */

   210

static inline void ccat_update_cmd(void __iomem * const ioaddr, uint8_t cmd,

   211

				   uint16_t clocks)

   212

{

   213

	__ccat_update_cmd(ioaddr, cmd, clocks);

   214

	wmb();

   215

	iowrite8(0xff, ioaddr + 0x7f8);

   216

	wait_until_busy_reset(ioaddr);

   217

}

   218

   219

/**

   220

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

   221

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

   222

 * @cmd: the command identifier

   223

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

   224

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

   225

 *

   226

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

   227

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

   228

 */

   229

static inline void ccat_update_cmd_addr(void __iomem * const ioaddr,

   230

					uint8_t cmd, uint16_t clocks,

   231

					uint32_t addr)

   232

{

   233

	const uint8_t addr_0 = SWAP_BITS(addr & 0xff);

   234

	const uint8_t addr_1 = SWAP_BITS((addr & 0xff00) >> 8);

   235

	const uint8_t addr_2 = SWAP_BITS((addr & 0xff0000) >> 16);

   236

	__ccat_update_cmd(ioaddr, cmd, clocks);

   237

	iowrite8(addr_2, ioaddr + 0x18);

   238

	iowrite8(addr_1, ioaddr + 0x20);

   239

	iowrite8(addr_0, ioaddr + 0x28);

   240

	wmb();

   241

	iowrite8(0xff, ioaddr + 0x7f8);

   242

	wait_until_busy_reset(ioaddr);

   243

}

   244

   245

/**

   246

 * ccat_get_prom_id() - Read CCAT PROM ID

   247

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

   248

 *

   249

 * Return: the CCAT FPGA's PROM identifier

   250

 */

   251

uint8_t ccat_get_prom_id(void __iomem * const ioaddr)

   252

{

   253

	ccat_update_cmd(ioaddr, CCAT_GET_PROM_ID);

   254

	return ioread8(ioaddr + 0x38);

   255

}

   256

   257

/**

   258

 * ccat_get_status() - Read CCAT Update status

   259

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

   260

 *

   261

 * Return: the current status of the CCAT Update function

   262

 */

   263

static uint8_t ccat_get_status(void __iomem * const ioaddr)

   264

{

   265

	ccat_update_cmd(ioaddr, CCAT_READ_STATUS);

   266

	return ioread8(ioaddr + 0x20);

   267

}

   268

   269

/**

   270

 * ccat_wait_status_cleared() - wait until CCAT status is cleared

   271

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

   272

 *

   273

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

   274

 */

   275

   276

static void ccat_wait_status_cleared(void __iomem * const ioaddr)

   277

{

   278

	uint8_t status;

   279

	do {

   280

		status = ccat_get_status(ioaddr);

   281

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

   282

}

   283

   284

/**

   285

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

   286

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

   287

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

   288

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

   289

 * @buf: output buffer in user space

   290

 *

   291

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

   292

 * the user space buffer.

   293

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

   294

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

   295

 *

   296

 * Return: the number of bytes copied

   297

 */

   298

static int ccat_read_flash_block(void __iomem * const ioaddr,

   299

				 const uint32_t addr, const uint16_t len,

   300

				 char __user * const buf)

   301

{

   302

	uint16_t i;

   303

	const uint16_t clocks = 8 * len;

   304

	ccat_update_cmd_addr(ioaddr, CCAT_READ_FLASH + clocks, addr);

   305

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

   306

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

   307

	}

   308

	return len;

   309

}

   310

   311

/**

   312

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

   313

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

   314

 * @buf: output buffer in user space

   315

 * @len: number of bytes to read

   316

 * @off: offset in the configuration data

   317

 *

   318

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

   319

 * flash to the user space buffer.

   320

 *

   321

 * Return: the number of bytes copied

   322

 */

   323

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

   324

			   uint32_t len, loff_t * off)

   325

{

   326

	const loff_t start = *off;

   327

	while (len > CCAT_DATA_BLOCK_SIZE) {

   328

		*off +=

   329

		    ccat_read_flash_block(ioaddr, *off, CCAT_DATA_BLOCK_SIZE,

   330

					  buf);

   331

		buf += CCAT_DATA_BLOCK_SIZE;

   332

		len -= CCAT_DATA_BLOCK_SIZE;

   333

	}

   334

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

   335

	return *off - start;

   336

}

   337

   338

/**

   339

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

   340

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

   341

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

   342

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

   343

 * @buf: input buffer

   344

 *

   345

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

   346

 *

   347

 * Return: the number of bytes copied

   348

 */

   349

static int ccat_write_flash_block(void __iomem * const ioaddr,

   350

				  const uint32_t addr, const uint16_t len,

   351

				  const char *const buf)

   352

{

   353

	const uint16_t clocks = 8 * len;

   354

	uint16_t i;

   355

	ccat_update_cmd(ioaddr, CCAT_WRITE_ENABLE);

   356

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

   357

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

   358

	}

   359

	ccat_update_cmd_addr(ioaddr, CCAT_WRITE_FLASH + clocks, addr);

   360

	ccat_wait_status_cleared(ioaddr);

   361

	return len;

   362

}

   363

   364

/**

   365

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

   366

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

   367

 */

   368

static void ccat_write_flash(const struct update_buffer *const update)

   369

{

   370

	const char *buf = update->data;

   371

	uint32_t off = 0;

   372

	size_t len = update->size;

   373

	while (len > CCAT_WRITE_BLOCK_SIZE) {

   374

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

   375

				       (uint16_t) CCAT_WRITE_BLOCK_SIZE, buf);

   376

		off += CCAT_WRITE_BLOCK_SIZE;

   377

		buf += CCAT_WRITE_BLOCK_SIZE;

   378

		len -= CCAT_WRITE_BLOCK_SIZE;

   379

	}

   380

	ccat_write_flash_block(update->update->ioaddr, off, (uint16_t) len,

   381

			       buf);

   382

}

   383

   384

/**

   385

 * ccat_update_init() - Initialize the CCAT Update function

   386

 */

   387

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

   388

				     void __iomem * const addr)

   389

{

   390

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

   391

	if (!update) {

   392

		return NULL;

   393

	}

   394

	kref_init(&update->refcount);

   395

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

   396

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

   397

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

   398

   399

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

   400

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

   401

			update->info.nRevision);

   402

		goto cleanup;

   403

	}

   404

   405

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

   406

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

   407

		goto cleanup;

   408

	}

   409

   410

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

   411

	if (NULL == update->class) {

   412

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

   413

		goto cleanup;

   414

	}

   415

   416

	if (NULL ==

   417

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

   418

			  "ccat_update")) {

   419

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

   420

		goto cleanup;

   421

	}

   422

   423

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

   424

	update->cdev.owner = THIS_MODULE;

   425

	update->cdev.ops = &update_ops;

   426

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

   427

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

   428

		goto cleanup;

   429

	}

   430

	return update;

   431

cleanup:

   432

	kref_put(&update->refcount, ccat_update_destroy);

   433

	return NULL;

   434

}

   435

   436

/**

   437

 * ccat_update_destroy() - Cleanup the CCAT Update function

   438

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

   439

 *

   440

 * Retrieves the parent struct ccat_update and destroys it.

   441

 */

   442

static void ccat_update_destroy(struct kref *ref)

   443

{

   444

	struct ccat_update *update =

   445

	    container_of(ref, struct ccat_update, refcount);

   446

	cdev_del(&update->cdev);

   447

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

   448

	class_destroy(update->class);

   449

	unregister_chrdev_region(update->dev, 1);

   450

	kfree(update);

   451

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

   452

}

   453

   454

/**

   455

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

   456

 */

   457

void ccat_update_remove(struct ccat_update *update)

   458

{

   459

	kref_put(&update->refcount, ccat_update_destroy);

   460

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

   461

}