blob: 7ce6065dc20e806a06845f08bcec084adbb4418d [file] [log] [blame]
Ira Snyder0e1d7152011-02-11 13:34:30 +00001/*
2 * CARMA Board DATA-FPGA Programmer
3 *
4 * Copyright (c) 2009-2011 Ira W. Snyder <iws@ovro.caltech.edu>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
10 */
11
12#include <linux/dma-mapping.h>
13#include <linux/of_platform.h>
14#include <linux/completion.h>
15#include <linux/miscdevice.h>
16#include <linux/dmaengine.h>
17#include <linux/interrupt.h>
18#include <linux/highmem.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/mutex.h>
22#include <linux/delay.h>
23#include <linux/init.h>
24#include <linux/leds.h>
25#include <linux/slab.h>
26#include <linux/kref.h>
27#include <linux/fs.h>
28#include <linux/io.h>
29
30#include <media/videobuf-dma-sg.h>
31
32/* MPC8349EMDS specific get_immrbase() */
33#include <sysdev/fsl_soc.h>
34
35static const char drv_name[] = "carma-fpga-program";
36
37/*
38 * Firmware images are always this exact size
39 *
40 * 12849552 bytes for a CARMA Digitizer Board (EP2S90 FPGAs)
41 * 18662880 bytes for a CARMA Correlator Board (EP2S130 FPGAs)
42 */
43#define FW_SIZE_EP2S90 12849552
44#define FW_SIZE_EP2S130 18662880
45
46struct fpga_dev {
47 struct miscdevice miscdev;
48
49 /* Reference count */
50 struct kref ref;
51
52 /* Device Registers */
53 struct device *dev;
54 void __iomem *regs;
55 void __iomem *immr;
56
57 /* Freescale DMA Device */
58 struct dma_chan *chan;
59
60 /* Interrupts */
61 int irq, status;
62 struct completion completion;
63
64 /* FPGA Bitfile */
65 struct mutex lock;
66
67 struct videobuf_dmabuf vb;
68 bool vb_allocated;
69
70 /* max size and written bytes */
71 size_t fw_size;
72 size_t bytes;
73};
74
75/*
76 * FPGA Bitfile Helpers
77 */
78
79/**
80 * fpga_drop_firmware_data() - drop the bitfile image from memory
81 * @priv: the driver's private data structure
82 *
83 * LOCKING: must hold priv->lock
84 */
85static void fpga_drop_firmware_data(struct fpga_dev *priv)
86{
87 videobuf_dma_free(&priv->vb);
88 priv->vb_allocated = false;
89 priv->bytes = 0;
90}
91
92/*
93 * Private Data Reference Count
94 */
95
96static void fpga_dev_remove(struct kref *ref)
97{
98 struct fpga_dev *priv = container_of(ref, struct fpga_dev, ref);
99
100 /* free any firmware image that was not programmed */
101 fpga_drop_firmware_data(priv);
102
103 mutex_destroy(&priv->lock);
104 kfree(priv);
105}
106
107/*
108 * LED Trigger (could be a seperate module)
109 */
110
111/*
112 * NOTE: this whole thing does have the problem that whenever the led's are
113 * NOTE: first set to use the fpga trigger, they could be in the wrong state
114 */
115
116DEFINE_LED_TRIGGER(ledtrig_fpga);
117
118static void ledtrig_fpga_programmed(bool enabled)
119{
120 if (enabled)
121 led_trigger_event(ledtrig_fpga, LED_FULL);
122 else
123 led_trigger_event(ledtrig_fpga, LED_OFF);
124}
125
126/*
127 * FPGA Register Helpers
128 */
129
130/* Register Definitions */
131#define FPGA_CONFIG_CONTROL 0x40
132#define FPGA_CONFIG_STATUS 0x44
133#define FPGA_CONFIG_FIFO_SIZE 0x48
134#define FPGA_CONFIG_FIFO_USED 0x4C
135#define FPGA_CONFIG_TOTAL_BYTE_COUNT 0x50
136#define FPGA_CONFIG_CUR_BYTE_COUNT 0x54
137
138#define FPGA_FIFO_ADDRESS 0x3000
139
140static int fpga_fifo_size(void __iomem *regs)
141{
142 return ioread32be(regs + FPGA_CONFIG_FIFO_SIZE);
143}
144
145#define CFG_STATUS_ERR_MASK 0xfffe
146
147static int fpga_config_error(void __iomem *regs)
148{
149 return ioread32be(regs + FPGA_CONFIG_STATUS) & CFG_STATUS_ERR_MASK;
150}
151
152static int fpga_fifo_empty(void __iomem *regs)
153{
154 return ioread32be(regs + FPGA_CONFIG_FIFO_USED) == 0;
155}
156
157static void fpga_fifo_write(void __iomem *regs, u32 val)
158{
159 iowrite32be(val, regs + FPGA_FIFO_ADDRESS);
160}
161
162static void fpga_set_byte_count(void __iomem *regs, u32 count)
163{
164 iowrite32be(count, regs + FPGA_CONFIG_TOTAL_BYTE_COUNT);
165}
166
167#define CFG_CTL_ENABLE (1 << 0)
168#define CFG_CTL_RESET (1 << 1)
169#define CFG_CTL_DMA (1 << 2)
170
171static void fpga_programmer_enable(struct fpga_dev *priv, bool dma)
172{
173 u32 val;
174
175 val = (dma) ? (CFG_CTL_ENABLE | CFG_CTL_DMA) : CFG_CTL_ENABLE;
176 iowrite32be(val, priv->regs + FPGA_CONFIG_CONTROL);
177}
178
179static void fpga_programmer_disable(struct fpga_dev *priv)
180{
181 iowrite32be(0x0, priv->regs + FPGA_CONFIG_CONTROL);
182}
183
184static void fpga_dump_registers(struct fpga_dev *priv)
185{
186 u32 control, status, size, used, total, curr;
187
188 /* good status: do nothing */
189 if (priv->status == 0)
190 return;
191
192 /* Dump all status registers */
193 control = ioread32be(priv->regs + FPGA_CONFIG_CONTROL);
194 status = ioread32be(priv->regs + FPGA_CONFIG_STATUS);
195 size = ioread32be(priv->regs + FPGA_CONFIG_FIFO_SIZE);
196 used = ioread32be(priv->regs + FPGA_CONFIG_FIFO_USED);
197 total = ioread32be(priv->regs + FPGA_CONFIG_TOTAL_BYTE_COUNT);
198 curr = ioread32be(priv->regs + FPGA_CONFIG_CUR_BYTE_COUNT);
199
200 dev_err(priv->dev, "Configuration failed, dumping status registers\n");
201 dev_err(priv->dev, "Control: 0x%.8x\n", control);
202 dev_err(priv->dev, "Status: 0x%.8x\n", status);
203 dev_err(priv->dev, "FIFO Size: 0x%.8x\n", size);
204 dev_err(priv->dev, "FIFO Used: 0x%.8x\n", used);
205 dev_err(priv->dev, "FIFO Total: 0x%.8x\n", total);
206 dev_err(priv->dev, "FIFO Curr: 0x%.8x\n", curr);
207}
208
209/*
210 * FPGA Power Supply Code
211 */
212
213#define CTL_PWR_CONTROL 0x2006
214#define CTL_PWR_STATUS 0x200A
215#define CTL_PWR_FAIL 0x200B
216
217#define PWR_CONTROL_ENABLE 0x01
218
219#define PWR_STATUS_ERROR_MASK 0x10
220#define PWR_STATUS_GOOD 0x0f
221
222/*
223 * Determine if the FPGA power is good for all supplies
224 */
225static bool fpga_power_good(struct fpga_dev *priv)
226{
227 u8 val;
228
229 val = ioread8(priv->regs + CTL_PWR_STATUS);
230 if (val & PWR_STATUS_ERROR_MASK)
231 return false;
232
233 return val == PWR_STATUS_GOOD;
234}
235
236/*
237 * Disable the FPGA power supplies
238 */
239static void fpga_disable_power_supplies(struct fpga_dev *priv)
240{
241 unsigned long start;
242 u8 val;
243
244 iowrite8(0x0, priv->regs + CTL_PWR_CONTROL);
245
246 /*
247 * Wait 500ms for the power rails to discharge
248 *
249 * Without this delay, the CTL-CPLD state machine can get into a
250 * state where it is waiting for the power-goods to assert, but they
251 * never do. This only happens when enabling and disabling the
252 * power sequencer very rapidly.
253 *
254 * The loop below will also wait for the power goods to de-assert,
255 * but testing has shown that they are always disabled by the time
256 * the sleep completes. However, omitting the sleep and only waiting
257 * for the power-goods to de-assert was not sufficient to ensure
258 * that the power sequencer would not wedge itself.
259 */
260 msleep(500);
261
262 start = jiffies;
263 while (time_before(jiffies, start + HZ)) {
264 val = ioread8(priv->regs + CTL_PWR_STATUS);
265 if (!(val & PWR_STATUS_GOOD))
266 break;
267
268 usleep_range(5000, 10000);
269 }
270
271 val = ioread8(priv->regs + CTL_PWR_STATUS);
272 if (val & PWR_STATUS_GOOD) {
273 dev_err(priv->dev, "power disable failed: "
274 "power goods: status 0x%.2x\n", val);
275 }
276
277 if (val & PWR_STATUS_ERROR_MASK) {
278 dev_err(priv->dev, "power disable failed: "
279 "alarm bit set: status 0x%.2x\n", val);
280 }
281}
282
283/**
284 * fpga_enable_power_supplies() - enable the DATA-FPGA power supplies
285 * @priv: the driver's private data structure
286 *
287 * Enable the DATA-FPGA power supplies, waiting up to 1 second for
288 * them to enable successfully.
289 *
290 * Returns 0 on success, -ERRNO otherwise
291 */
292static int fpga_enable_power_supplies(struct fpga_dev *priv)
293{
294 unsigned long start = jiffies;
295
296 if (fpga_power_good(priv)) {
297 dev_dbg(priv->dev, "power was already good\n");
298 return 0;
299 }
300
301 iowrite8(PWR_CONTROL_ENABLE, priv->regs + CTL_PWR_CONTROL);
302 while (time_before(jiffies, start + HZ)) {
303 if (fpga_power_good(priv))
304 return 0;
305
306 usleep_range(5000, 10000);
307 }
308
309 return fpga_power_good(priv) ? 0 : -ETIMEDOUT;
310}
311
312/*
313 * Determine if the FPGA power supplies are all enabled
314 */
315static bool fpga_power_enabled(struct fpga_dev *priv)
316{
317 u8 val;
318
319 val = ioread8(priv->regs + CTL_PWR_CONTROL);
320 if (val & PWR_CONTROL_ENABLE)
321 return true;
322
323 return false;
324}
325
326/*
327 * Determine if the FPGA's are programmed and running correctly
328 */
329static bool fpga_running(struct fpga_dev *priv)
330{
331 if (!fpga_power_good(priv))
332 return false;
333
334 /* Check the config done bit */
335 return ioread32be(priv->regs + FPGA_CONFIG_STATUS) & (1 << 18);
336}
337
338/*
339 * FPGA Programming Code
340 */
341
342/**
343 * fpga_program_block() - put a block of data into the programmer's FIFO
344 * @priv: the driver's private data structure
345 * @buf: the data to program
346 * @count: the length of data to program (must be a multiple of 4 bytes)
347 *
348 * Returns 0 on success, -ERRNO otherwise
349 */
350static int fpga_program_block(struct fpga_dev *priv, void *buf, size_t count)
351{
352 u32 *data = buf;
353 int size = fpga_fifo_size(priv->regs);
354 int i, len;
355 unsigned long timeout;
356
357 /* enforce correct data length for the FIFO */
358 BUG_ON(count % 4 != 0);
359
360 while (count > 0) {
361
362 /* Get the size of the block to write (maximum is FIFO_SIZE) */
363 len = min_t(size_t, count, size);
364 timeout = jiffies + HZ / 4;
365
366 /* Write the block */
367 for (i = 0; i < len / 4; i++)
368 fpga_fifo_write(priv->regs, data[i]);
369
370 /* Update the amounts left */
371 count -= len;
372 data += len / 4;
373
374 /* Wait for the fifo to empty */
375 while (true) {
376
377 if (fpga_fifo_empty(priv->regs)) {
378 break;
379 } else {
380 dev_dbg(priv->dev, "Fifo not empty\n");
381 cpu_relax();
382 }
383
384 if (fpga_config_error(priv->regs)) {
385 dev_err(priv->dev, "Error detected\n");
386 return -EIO;
387 }
388
389 if (time_after(jiffies, timeout)) {
390 dev_err(priv->dev, "Fifo drain timeout\n");
391 return -ETIMEDOUT;
392 }
393
394 usleep_range(5000, 10000);
395 }
396 }
397
398 return 0;
399}
400
401/**
402 * fpga_program_cpu() - program the DATA-FPGA's using the CPU
403 * @priv: the driver's private data structure
404 *
405 * This is useful when the DMA programming method fails. It is possible to
406 * wedge the Freescale DMA controller such that the DMA programming method
407 * always fails. This method has always succeeded.
408 *
409 * Returns 0 on success, -ERRNO otherwise
410 */
411static noinline int fpga_program_cpu(struct fpga_dev *priv)
412{
413 int ret;
414
415 /* Disable the programmer */
416 fpga_programmer_disable(priv);
417
418 /* Set the total byte count */
419 fpga_set_byte_count(priv->regs, priv->bytes);
420 dev_dbg(priv->dev, "total byte count %u bytes\n", priv->bytes);
421
422 /* Enable the controller for programming */
423 fpga_programmer_enable(priv, false);
424 dev_dbg(priv->dev, "enabled the controller\n");
425
426 /* Write each chunk of the FPGA bitfile to FPGA programmer */
427 ret = fpga_program_block(priv, priv->vb.vaddr, priv->bytes);
428 if (ret)
429 goto out_disable_controller;
430
431 /* Wait for the interrupt handler to signal that programming finished */
432 ret = wait_for_completion_timeout(&priv->completion, 2 * HZ);
433 if (!ret) {
434 dev_err(priv->dev, "Timed out waiting for completion\n");
435 ret = -ETIMEDOUT;
436 goto out_disable_controller;
437 }
438
439 /* Retrieve the status from the interrupt handler */
440 ret = priv->status;
441
442out_disable_controller:
443 fpga_programmer_disable(priv);
444 return ret;
445}
446
447#define FIFO_DMA_ADDRESS 0xf0003000
448#define FIFO_MAX_LEN 4096
449
450/**
451 * fpga_program_dma() - program the DATA-FPGA's using the DMA engine
452 * @priv: the driver's private data structure
453 *
454 * Program the DATA-FPGA's using the Freescale DMA engine. This requires that
455 * the engine is programmed such that the hardware DMA request lines can
456 * control the entire DMA transaction. The system controller FPGA then
457 * completely offloads the programming from the CPU.
458 *
459 * Returns 0 on success, -ERRNO otherwise
460 */
461static noinline int fpga_program_dma(struct fpga_dev *priv)
462{
463 struct videobuf_dmabuf *vb = &priv->vb;
464 struct dma_chan *chan = priv->chan;
465 struct dma_async_tx_descriptor *tx;
466 size_t num_pages, len, avail = 0;
467 struct dma_slave_config config;
468 struct scatterlist *sg;
469 struct sg_table table;
470 dma_cookie_t cookie;
471 int ret, i;
472
473 /* Disable the programmer */
474 fpga_programmer_disable(priv);
475
476 /* Allocate a scatterlist for the DMA destination */
477 num_pages = DIV_ROUND_UP(priv->bytes, FIFO_MAX_LEN);
478 ret = sg_alloc_table(&table, num_pages, GFP_KERNEL);
479 if (ret) {
480 dev_err(priv->dev, "Unable to allocate dst scatterlist\n");
481 ret = -ENOMEM;
482 goto out_return;
483 }
484
485 /*
486 * This is an ugly hack
487 *
488 * We fill in a scatterlist as if it were mapped for DMA. This is
489 * necessary because there exists no better structure for this
490 * inside the kernel code.
491 *
492 * As an added bonus, we can use the DMAEngine API for all of this,
493 * rather than inventing another extremely similar API.
494 */
495 avail = priv->bytes;
496 for_each_sg(table.sgl, sg, num_pages, i) {
497 len = min_t(size_t, avail, FIFO_MAX_LEN);
498 sg_dma_address(sg) = FIFO_DMA_ADDRESS;
499 sg_dma_len(sg) = len;
500
501 avail -= len;
502 }
503
504 /* Map the buffer for DMA */
505 ret = videobuf_dma_map(priv->dev, &priv->vb);
506 if (ret) {
507 dev_err(priv->dev, "Unable to map buffer for DMA\n");
508 goto out_free_table;
509 }
510
511 /*
512 * Configure the DMA channel to transfer FIFO_SIZE / 2 bytes per
513 * transaction, and then put it under external control
514 */
515 memset(&config, 0, sizeof(config));
516 config.direction = DMA_TO_DEVICE;
517 config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
518 config.dst_maxburst = fpga_fifo_size(priv->regs) / 2 / 4;
519 ret = chan->device->device_control(chan, DMA_SLAVE_CONFIG,
520 (unsigned long)&config);
521 if (ret) {
522 dev_err(priv->dev, "DMA slave configuration failed\n");
523 goto out_dma_unmap;
524 }
525
526 ret = chan->device->device_control(chan, FSLDMA_EXTERNAL_START, 1);
527 if (ret) {
528 dev_err(priv->dev, "DMA external control setup failed\n");
529 goto out_dma_unmap;
530 }
531
532 /* setup and submit the DMA transaction */
533 tx = chan->device->device_prep_dma_sg(chan,
534 table.sgl, num_pages,
535 vb->sglist, vb->sglen, 0);
536 if (!tx) {
537 dev_err(priv->dev, "Unable to prep DMA transaction\n");
538 ret = -ENOMEM;
539 goto out_dma_unmap;
540 }
541
542 cookie = tx->tx_submit(tx);
543 if (dma_submit_error(cookie)) {
544 dev_err(priv->dev, "Unable to submit DMA transaction\n");
545 ret = -ENOMEM;
546 goto out_dma_unmap;
547 }
548
549 dma_async_memcpy_issue_pending(chan);
550
551 /* Set the total byte count */
552 fpga_set_byte_count(priv->regs, priv->bytes);
553 dev_dbg(priv->dev, "total byte count %u bytes\n", priv->bytes);
554
555 /* Enable the controller for DMA programming */
556 fpga_programmer_enable(priv, true);
557 dev_dbg(priv->dev, "enabled the controller\n");
558
559 /* Wait for the interrupt handler to signal that programming finished */
560 ret = wait_for_completion_timeout(&priv->completion, 2 * HZ);
561 if (!ret) {
562 dev_err(priv->dev, "Timed out waiting for completion\n");
563 ret = -ETIMEDOUT;
564 goto out_disable_controller;
565 }
566
567 /* Retrieve the status from the interrupt handler */
568 ret = priv->status;
569
570out_disable_controller:
571 fpga_programmer_disable(priv);
572out_dma_unmap:
573 videobuf_dma_unmap(priv->dev, vb);
574out_free_table:
575 sg_free_table(&table);
576out_return:
577 return ret;
578}
579
580/*
581 * Interrupt Handling
582 */
583
584static irqreturn_t fpga_irq(int irq, void *dev_id)
585{
586 struct fpga_dev *priv = dev_id;
587
588 /* Save the status */
589 priv->status = fpga_config_error(priv->regs) ? -EIO : 0;
590 dev_dbg(priv->dev, "INTERRUPT status %d\n", priv->status);
591 fpga_dump_registers(priv);
592
593 /* Disabling the programmer clears the interrupt */
594 fpga_programmer_disable(priv);
595
596 /* Notify any waiters */
597 complete(&priv->completion);
598
599 return IRQ_HANDLED;
600}
601
602/*
603 * SYSFS Helpers
604 */
605
606/**
607 * fpga_do_stop() - deconfigure (reset) the DATA-FPGA's
608 * @priv: the driver's private data structure
609 *
610 * LOCKING: must hold priv->lock
611 */
612static int fpga_do_stop(struct fpga_dev *priv)
613{
614 u32 val;
615
616 /* Set the led to unprogrammed */
617 ledtrig_fpga_programmed(false);
618
619 /* Pulse the config line to reset the FPGA's */
620 val = CFG_CTL_ENABLE | CFG_CTL_RESET;
621 iowrite32be(val, priv->regs + FPGA_CONFIG_CONTROL);
622 iowrite32be(0x0, priv->regs + FPGA_CONFIG_CONTROL);
623
624 return 0;
625}
626
627static noinline int fpga_do_program(struct fpga_dev *priv)
628{
629 int ret;
630
631 if (priv->bytes != priv->fw_size) {
632 dev_err(priv->dev, "Incorrect bitfile size: got %zu bytes, "
633 "should be %zu bytes\n",
634 priv->bytes, priv->fw_size);
635 return -EINVAL;
636 }
637
638 if (!fpga_power_enabled(priv)) {
639 dev_err(priv->dev, "Power not enabled\n");
640 return -EINVAL;
641 }
642
643 if (!fpga_power_good(priv)) {
644 dev_err(priv->dev, "Power not good\n");
645 return -EINVAL;
646 }
647
648 /* Set the LED to unprogrammed */
649 ledtrig_fpga_programmed(false);
650
651 /* Try to program the FPGA's using DMA */
652 ret = fpga_program_dma(priv);
653
654 /* If DMA failed or doesn't exist, try with CPU */
655 if (ret) {
656 dev_warn(priv->dev, "Falling back to CPU programming\n");
657 ret = fpga_program_cpu(priv);
658 }
659
660 if (ret) {
661 dev_err(priv->dev, "Unable to program FPGA's\n");
662 return ret;
663 }
664
665 /* Drop the firmware bitfile from memory */
666 fpga_drop_firmware_data(priv);
667
668 dev_dbg(priv->dev, "FPGA programming successful\n");
669 ledtrig_fpga_programmed(true);
670
671 return 0;
672}
673
674/*
675 * File Operations
676 */
677
678static int fpga_open(struct inode *inode, struct file *filp)
679{
680 /*
681 * The miscdevice layer puts our struct miscdevice into the
682 * filp->private_data field. We use this to find our private
683 * data and then overwrite it with our own private structure.
684 */
685 struct fpga_dev *priv = container_of(filp->private_data,
686 struct fpga_dev, miscdev);
687 unsigned int nr_pages;
688 int ret;
689
690 /* We only allow one process at a time */
691 ret = mutex_lock_interruptible(&priv->lock);
692 if (ret)
693 return ret;
694
695 filp->private_data = priv;
696 kref_get(&priv->ref);
697
698 /* Truncation: drop any existing data */
699 if (filp->f_flags & O_TRUNC)
700 priv->bytes = 0;
701
702 /* Check if we have already allocated a buffer */
703 if (priv->vb_allocated)
704 return 0;
705
706 /* Allocate a buffer to hold enough data for the bitfile */
707 nr_pages = DIV_ROUND_UP(priv->fw_size, PAGE_SIZE);
708 ret = videobuf_dma_init_kernel(&priv->vb, DMA_TO_DEVICE, nr_pages);
709 if (ret) {
710 dev_err(priv->dev, "unable to allocate data buffer\n");
711 mutex_unlock(&priv->lock);
712 kref_put(&priv->ref, fpga_dev_remove);
713 return ret;
714 }
715
716 priv->vb_allocated = true;
717 return 0;
718}
719
720static int fpga_release(struct inode *inode, struct file *filp)
721{
722 struct fpga_dev *priv = filp->private_data;
723
724 mutex_unlock(&priv->lock);
725 kref_put(&priv->ref, fpga_dev_remove);
726 return 0;
727}
728
729static ssize_t fpga_write(struct file *filp, const char __user *buf,
730 size_t count, loff_t *f_pos)
731{
732 struct fpga_dev *priv = filp->private_data;
733
734 /* FPGA bitfiles have an exact size: disallow anything else */
735 if (priv->bytes >= priv->fw_size)
736 return -ENOSPC;
737
738 count = min_t(size_t, priv->fw_size - priv->bytes, count);
739 if (copy_from_user(priv->vb.vaddr + priv->bytes, buf, count))
740 return -EFAULT;
741
742 priv->bytes += count;
743 return count;
744}
745
746static ssize_t fpga_read(struct file *filp, char __user *buf, size_t count,
747 loff_t *f_pos)
748{
749 struct fpga_dev *priv = filp->private_data;
750
751 count = min_t(size_t, priv->bytes - *f_pos, count);
752 if (copy_to_user(buf, priv->vb.vaddr + *f_pos, count))
753 return -EFAULT;
754
755 *f_pos += count;
756 return count;
757}
758
759static loff_t fpga_llseek(struct file *filp, loff_t offset, int origin)
760{
761 struct fpga_dev *priv = filp->private_data;
762 loff_t newpos;
763
764 /* only read-only opens are allowed to seek */
765 if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
766 return -EINVAL;
767
768 switch (origin) {
769 case SEEK_SET: /* seek relative to the beginning of the file */
770 newpos = offset;
771 break;
772 case SEEK_CUR: /* seek relative to current position in the file */
773 newpos = filp->f_pos + offset;
774 break;
775 case SEEK_END: /* seek relative to the end of the file */
776 newpos = priv->fw_size - offset;
777 break;
778 default:
779 return -EINVAL;
780 }
781
782 /* check for sanity */
783 if (newpos > priv->fw_size)
784 return -EINVAL;
785
786 filp->f_pos = newpos;
787 return newpos;
788}
789
790static const struct file_operations fpga_fops = {
791 .open = fpga_open,
792 .release = fpga_release,
793 .write = fpga_write,
794 .read = fpga_read,
795 .llseek = fpga_llseek,
796};
797
798/*
799 * Device Attributes
800 */
801
802static ssize_t pfail_show(struct device *dev, struct device_attribute *attr,
803 char *buf)
804{
805 struct fpga_dev *priv = dev_get_drvdata(dev);
806 u8 val;
807
808 val = ioread8(priv->regs + CTL_PWR_FAIL);
809 return snprintf(buf, PAGE_SIZE, "0x%.2x\n", val);
810}
811
812static ssize_t pgood_show(struct device *dev, struct device_attribute *attr,
813 char *buf)
814{
815 struct fpga_dev *priv = dev_get_drvdata(dev);
816 return snprintf(buf, PAGE_SIZE, "%d\n", fpga_power_good(priv));
817}
818
819static ssize_t penable_show(struct device *dev, struct device_attribute *attr,
820 char *buf)
821{
822 struct fpga_dev *priv = dev_get_drvdata(dev);
823 return snprintf(buf, PAGE_SIZE, "%d\n", fpga_power_enabled(priv));
824}
825
826static ssize_t penable_store(struct device *dev, struct device_attribute *attr,
827 const char *buf, size_t count)
828{
829 struct fpga_dev *priv = dev_get_drvdata(dev);
830 unsigned long val;
831 int ret;
832
833 if (strict_strtoul(buf, 0, &val))
834 return -EINVAL;
835
836 if (val) {
837 ret = fpga_enable_power_supplies(priv);
838 if (ret)
839 return ret;
840 } else {
841 fpga_do_stop(priv);
842 fpga_disable_power_supplies(priv);
843 }
844
845 return count;
846}
847
848static ssize_t program_show(struct device *dev, struct device_attribute *attr,
849 char *buf)
850{
851 struct fpga_dev *priv = dev_get_drvdata(dev);
852 return snprintf(buf, PAGE_SIZE, "%d\n", fpga_running(priv));
853}
854
855static ssize_t program_store(struct device *dev, struct device_attribute *attr,
856 const char *buf, size_t count)
857{
858 struct fpga_dev *priv = dev_get_drvdata(dev);
859 unsigned long val;
860 int ret;
861
862 if (strict_strtoul(buf, 0, &val))
863 return -EINVAL;
864
865 /* We can't have an image writer and be programming simultaneously */
866 if (mutex_lock_interruptible(&priv->lock))
867 return -ERESTARTSYS;
868
869 /* Program or Reset the FPGA's */
870 ret = val ? fpga_do_program(priv) : fpga_do_stop(priv);
871 if (ret)
872 goto out_unlock;
873
874 /* Success */
875 ret = count;
876
877out_unlock:
878 mutex_unlock(&priv->lock);
879 return ret;
880}
881
882static DEVICE_ATTR(power_fail, S_IRUGO, pfail_show, NULL);
883static DEVICE_ATTR(power_good, S_IRUGO, pgood_show, NULL);
884static DEVICE_ATTR(power_enable, S_IRUGO | S_IWUSR,
885 penable_show, penable_store);
886
887static DEVICE_ATTR(program, S_IRUGO | S_IWUSR,
888 program_show, program_store);
889
890static struct attribute *fpga_attributes[] = {
891 &dev_attr_power_fail.attr,
892 &dev_attr_power_good.attr,
893 &dev_attr_power_enable.attr,
894 &dev_attr_program.attr,
895 NULL,
896};
897
898static const struct attribute_group fpga_attr_group = {
899 .attrs = fpga_attributes,
900};
901
902/*
903 * OpenFirmware Device Subsystem
904 */
905
906#define SYS_REG_VERSION 0x00
907#define SYS_REG_GEOGRAPHIC 0x10
908
909static bool dma_filter(struct dma_chan *chan, void *data)
910{
911 /*
912 * DMA Channel #0 is the only acceptable device
913 *
914 * This probably won't survive an unload/load cycle of the Freescale
915 * DMAEngine driver, but that won't be a problem
916 */
917 return chan->chan_id == 0 && chan->device->dev_id == 0;
918}
919
920static int fpga_of_remove(struct platform_device *op)
921{
922 struct fpga_dev *priv = dev_get_drvdata(&op->dev);
923 struct device *this_device = priv->miscdev.this_device;
924
925 sysfs_remove_group(&this_device->kobj, &fpga_attr_group);
926 misc_deregister(&priv->miscdev);
927
928 free_irq(priv->irq, priv);
929 irq_dispose_mapping(priv->irq);
930
931 /* make sure the power supplies are off */
932 fpga_disable_power_supplies(priv);
933
934 /* unmap registers */
935 iounmap(priv->immr);
936 iounmap(priv->regs);
937
938 dma_release_channel(priv->chan);
939
940 /* drop our reference to the private data structure */
941 kref_put(&priv->ref, fpga_dev_remove);
942 return 0;
943}
944
945/* CTL-CPLD Version Register */
946#define CTL_CPLD_VERSION 0x2000
947
948static int fpga_of_probe(struct platform_device *op,
949 const struct of_device_id *match)
950{
951 struct device_node *of_node = op->dev.of_node;
952 struct device *this_device;
953 struct fpga_dev *priv;
954 dma_cap_mask_t mask;
955 u32 ver;
956 int ret;
957
958 /* Allocate private data */
959 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
960 if (!priv) {
961 dev_err(&op->dev, "Unable to allocate private data\n");
962 ret = -ENOMEM;
963 goto out_return;
964 }
965
966 /* Setup the miscdevice */
967 priv->miscdev.minor = MISC_DYNAMIC_MINOR;
968 priv->miscdev.name = drv_name;
969 priv->miscdev.fops = &fpga_fops;
970
971 kref_init(&priv->ref);
972
973 dev_set_drvdata(&op->dev, priv);
974 priv->dev = &op->dev;
975 mutex_init(&priv->lock);
976 init_completion(&priv->completion);
977 videobuf_dma_init(&priv->vb);
978
979 dev_set_drvdata(priv->dev, priv);
980 dma_cap_zero(mask);
981 dma_cap_set(DMA_MEMCPY, mask);
982 dma_cap_set(DMA_INTERRUPT, mask);
983 dma_cap_set(DMA_SLAVE, mask);
984 dma_cap_set(DMA_SG, mask);
985
986 /* Get control of DMA channel #0 */
987 priv->chan = dma_request_channel(mask, dma_filter, NULL);
988 if (!priv->chan) {
989 dev_err(&op->dev, "Unable to acquire DMA channel #0\n");
990 ret = -ENODEV;
991 goto out_free_priv;
992 }
993
994 /* Remap the registers for use */
995 priv->regs = of_iomap(of_node, 0);
996 if (!priv->regs) {
997 dev_err(&op->dev, "Unable to ioremap registers\n");
998 ret = -ENOMEM;
999 goto out_dma_release_channel;
1000 }
1001
1002 /* Remap the IMMR for use */
1003 priv->immr = ioremap(get_immrbase(), 0x100000);
1004 if (!priv->immr) {
1005 dev_err(&op->dev, "Unable to ioremap IMMR\n");
1006 ret = -ENOMEM;
1007 goto out_unmap_regs;
1008 }
1009
1010 /*
1011 * Check that external DMA is configured
1012 *
1013 * U-Boot does this for us, but we should check it and bail out if
1014 * there is a problem. Failing to have this register setup correctly
1015 * will cause the DMA controller to transfer a single cacheline
1016 * worth of data, then wedge itself.
1017 */
1018 if ((ioread32be(priv->immr + 0x114) & 0xE00) != 0xE00) {
1019 dev_err(&op->dev, "External DMA control not configured\n");
1020 ret = -ENODEV;
1021 goto out_unmap_immr;
1022 }
1023
1024 /*
1025 * Check the CTL-CPLD version
1026 *
1027 * This driver uses the CTL-CPLD DATA-FPGA power sequencer, and we
1028 * don't want to run on any version of the CTL-CPLD that does not use
1029 * a compatible register layout.
1030 *
1031 * v2: changed register layout, added power sequencer
1032 * v3: added glitch filter on the i2c overcurrent/overtemp outputs
1033 */
1034 ver = ioread8(priv->regs + CTL_CPLD_VERSION);
1035 if (ver != 0x02 && ver != 0x03) {
1036 dev_err(&op->dev, "CTL-CPLD is not version 0x02 or 0x03!\n");
1037 ret = -ENODEV;
1038 goto out_unmap_immr;
1039 }
1040
1041 /* Set the exact size that the firmware image should be */
1042 ver = ioread32be(priv->regs + SYS_REG_VERSION);
1043 priv->fw_size = (ver & (1 << 18)) ? FW_SIZE_EP2S130 : FW_SIZE_EP2S90;
1044
1045 /* Find the correct IRQ number */
1046 priv->irq = irq_of_parse_and_map(of_node, 0);
1047 if (priv->irq == NO_IRQ) {
1048 dev_err(&op->dev, "Unable to find IRQ line\n");
1049 ret = -ENODEV;
1050 goto out_unmap_immr;
1051 }
1052
1053 /* Request the IRQ */
1054 ret = request_irq(priv->irq, fpga_irq, IRQF_SHARED, drv_name, priv);
1055 if (ret) {
1056 dev_err(&op->dev, "Unable to request IRQ %d\n", priv->irq);
1057 ret = -ENODEV;
1058 goto out_irq_dispose_mapping;
1059 }
1060
1061 /* Reset and stop the FPGA's, just in case */
1062 fpga_do_stop(priv);
1063
1064 /* Register the miscdevice */
1065 ret = misc_register(&priv->miscdev);
1066 if (ret) {
1067 dev_err(&op->dev, "Unable to register miscdevice\n");
1068 goto out_free_irq;
1069 }
1070
1071 /* Create the sysfs files */
1072 this_device = priv->miscdev.this_device;
1073 dev_set_drvdata(this_device, priv);
1074 ret = sysfs_create_group(&this_device->kobj, &fpga_attr_group);
1075 if (ret) {
1076 dev_err(&op->dev, "Unable to create sysfs files\n");
1077 goto out_misc_deregister;
1078 }
1079
1080 dev_info(priv->dev, "CARMA FPGA Programmer: %s rev%s with %s FPGAs\n",
1081 (ver & (1 << 17)) ? "Correlator" : "Digitizer",
1082 (ver & (1 << 16)) ? "B" : "A",
1083 (ver & (1 << 18)) ? "EP2S130" : "EP2S90");
1084
1085 return 0;
1086
1087out_misc_deregister:
1088 misc_deregister(&priv->miscdev);
1089out_free_irq:
1090 free_irq(priv->irq, priv);
1091out_irq_dispose_mapping:
1092 irq_dispose_mapping(priv->irq);
1093out_unmap_immr:
1094 iounmap(priv->immr);
1095out_unmap_regs:
1096 iounmap(priv->regs);
1097out_dma_release_channel:
1098 dma_release_channel(priv->chan);
1099out_free_priv:
1100 kref_put(&priv->ref, fpga_dev_remove);
1101out_return:
1102 return ret;
1103}
1104
1105static struct of_device_id fpga_of_match[] = {
1106 { .compatible = "carma,fpga-programmer", },
1107 {},
1108};
1109
1110static struct of_platform_driver fpga_of_driver = {
1111 .probe = fpga_of_probe,
1112 .remove = fpga_of_remove,
1113 .driver = {
1114 .name = drv_name,
1115 .of_match_table = fpga_of_match,
1116 .owner = THIS_MODULE,
1117 },
1118};
1119
1120/*
1121 * Module Init / Exit
1122 */
1123
1124static int __init fpga_init(void)
1125{
1126 led_trigger_register_simple("fpga", &ledtrig_fpga);
1127 return of_register_platform_driver(&fpga_of_driver);
1128}
1129
1130static void __exit fpga_exit(void)
1131{
1132 of_unregister_platform_driver(&fpga_of_driver);
1133 led_trigger_unregister_simple(ledtrig_fpga);
1134}
1135
1136MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
1137MODULE_DESCRIPTION("CARMA Board DATA-FPGA Programmer");
1138MODULE_LICENSE("GPL");
1139
1140module_init(fpga_init);
1141module_exit(fpga_exit);