1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * gsc_hpdi.c
4  * Comedi driver the General Standards Corporation
5  * High Speed Parallel Digital Interface rs485 boards.
6  *
7  * Author:  Frank Mori Hess <fmhess@users.sourceforge.net>
8  * Copyright (C) 2003 Coherent Imaging Systems
9  *
10  * COMEDI - Linux Control and Measurement Device Interface
11  * Copyright (C) 1997-8 David A. Schleef <ds@schleef.org>
12  */
13 
14 /*
15  * Driver: gsc_hpdi
16  * Description: General Standards Corporation High
17  *    Speed Parallel Digital Interface rs485 boards
18  * Author: Frank Mori Hess <fmhess@users.sourceforge.net>
19  * Status: only receive mode works, transmit not supported
20  * Updated: Thu, 01 Nov 2012 16:17:38 +0000
21  * Devices: [General Standards Corporation] PCI-HPDI32 (gsc_hpdi),
22  *   PMC-HPDI32
23  *
24  * Configuration options:
25  *    None.
26  *
27  * Manual configuration of supported devices is not supported; they are
28  * configured automatically.
29  *
30  * There are some additional hpdi models available from GSC for which
31  * support could be added to this driver.
32  */
33 
34 #include <linux/module.h>
35 #include <linux/delay.h>
36 #include <linux/interrupt.h>
37 
38 #include "../comedi_pci.h"
39 
40 #include "plx9080.h"
41 
42 /*
43  * PCI BAR2 Register map (dev->mmio)
44  */
45 #define FIRMWARE_REV_REG			0x00
46 #define FEATURES_REG_PRESENT_BIT		BIT(15)
47 #define BOARD_CONTROL_REG			0x04
48 #define BOARD_RESET_BIT				BIT(0)
49 #define TX_FIFO_RESET_BIT			BIT(1)
50 #define RX_FIFO_RESET_BIT			BIT(2)
51 #define TX_ENABLE_BIT				BIT(4)
52 #define RX_ENABLE_BIT				BIT(5)
53 #define DEMAND_DMA_DIRECTION_TX_BIT		BIT(6)  /* ch 0 only */
54 #define LINE_VALID_ON_STATUS_VALID_BIT		BIT(7)
55 #define START_TX_BIT				BIT(8)
56 #define CABLE_THROTTLE_ENABLE_BIT		BIT(9)
57 #define TEST_MODE_ENABLE_BIT			BIT(31)
58 #define BOARD_STATUS_REG			0x08
59 #define COMMAND_LINE_STATUS_MASK		(0x7f << 0)
60 #define TX_IN_PROGRESS_BIT			BIT(7)
61 #define TX_NOT_EMPTY_BIT			BIT(8)
62 #define TX_NOT_ALMOST_EMPTY_BIT			BIT(9)
63 #define TX_NOT_ALMOST_FULL_BIT			BIT(10)
64 #define TX_NOT_FULL_BIT				BIT(11)
65 #define RX_NOT_EMPTY_BIT			BIT(12)
66 #define RX_NOT_ALMOST_EMPTY_BIT			BIT(13)
67 #define RX_NOT_ALMOST_FULL_BIT			BIT(14)
68 #define RX_NOT_FULL_BIT				BIT(15)
69 #define BOARD_JUMPER0_INSTALLED_BIT		BIT(16)
70 #define BOARD_JUMPER1_INSTALLED_BIT		BIT(17)
71 #define TX_OVERRUN_BIT				BIT(21)
72 #define RX_UNDERRUN_BIT				BIT(22)
73 #define RX_OVERRUN_BIT				BIT(23)
74 #define TX_PROG_ALMOST_REG			0x0c
75 #define RX_PROG_ALMOST_REG			0x10
76 #define ALMOST_EMPTY_BITS(x)			(((x) & 0xffff) << 0)
77 #define ALMOST_FULL_BITS(x)			(((x) & 0xff) << 16)
78 #define FEATURES_REG				0x14
79 #define FIFO_SIZE_PRESENT_BIT			BIT(0)
80 #define FIFO_WORDS_PRESENT_BIT			BIT(1)
81 #define LEVEL_EDGE_INTERRUPTS_PRESENT_BIT	BIT(2)
82 #define GPIO_SUPPORTED_BIT			BIT(3)
83 #define PLX_DMA_CH1_SUPPORTED_BIT		BIT(4)
84 #define OVERRUN_UNDERRUN_SUPPORTED_BIT		BIT(5)
85 #define FIFO_REG				0x18
86 #define TX_STATUS_COUNT_REG			0x1c
87 #define TX_LINE_VALID_COUNT_REG			0x20,
88 #define TX_LINE_INVALID_COUNT_REG		0x24
89 #define RX_STATUS_COUNT_REG			0x28
90 #define RX_LINE_COUNT_REG			0x2c
91 #define INTERRUPT_CONTROL_REG			0x30
92 #define FRAME_VALID_START_INTR			BIT(0)
93 #define FRAME_VALID_END_INTR			BIT(1)
94 #define TX_FIFO_EMPTY_INTR			BIT(8)
95 #define TX_FIFO_ALMOST_EMPTY_INTR		BIT(9)
96 #define TX_FIFO_ALMOST_FULL_INTR		BIT(10)
97 #define TX_FIFO_FULL_INTR			BIT(11)
98 #define RX_EMPTY_INTR				BIT(12)
99 #define RX_ALMOST_EMPTY_INTR			BIT(13)
100 #define RX_ALMOST_FULL_INTR			BIT(14)
101 #define RX_FULL_INTR				BIT(15)
102 #define INTERRUPT_STATUS_REG			0x34
103 #define TX_CLOCK_DIVIDER_REG			0x38
104 #define TX_FIFO_SIZE_REG			0x40
105 #define RX_FIFO_SIZE_REG			0x44
106 #define FIFO_SIZE_MASK				(0xfffff << 0)
107 #define TX_FIFO_WORDS_REG			0x48
108 #define RX_FIFO_WORDS_REG			0x4c
109 #define INTERRUPT_EDGE_LEVEL_REG		0x50
110 #define INTERRUPT_POLARITY_REG			0x54
111 
112 #define TIMER_BASE				50	/* 20MHz master clock */
113 #define DMA_BUFFER_SIZE				0x10000
114 #define NUM_DMA_BUFFERS				4
115 #define NUM_DMA_DESCRIPTORS			256
116 
117 struct hpdi_private {
118 	void __iomem *plx9080_mmio;
119 	u32 *dio_buffer[NUM_DMA_BUFFERS];	/* dma buffers */
120 	/* physical addresses of dma buffers */
121 	dma_addr_t dio_buffer_phys_addr[NUM_DMA_BUFFERS];
122 	/*
123 	 * array of dma descriptors read by plx9080, allocated to get proper
124 	 * alignment
125 	 */
126 	struct plx_dma_desc *dma_desc;
127 	/* physical address of dma descriptor array */
128 	dma_addr_t dma_desc_phys_addr;
129 	unsigned int num_dma_descriptors;
130 	/* pointer to start of buffers indexed by descriptor */
131 	u32 *desc_dio_buffer[NUM_DMA_DESCRIPTORS];
132 	/* index of the dma descriptor that is currently being used */
133 	unsigned int dma_desc_index;
134 	unsigned int tx_fifo_size;
135 	unsigned int rx_fifo_size;
136 	unsigned long dio_count;
137 	/* number of bytes at which to generate COMEDI_CB_BLOCK events */
138 	unsigned int block_size;
139 };
140 
gsc_hpdi_drain_dma(struct comedi_device * dev,unsigned int channel)141 static void gsc_hpdi_drain_dma(struct comedi_device *dev, unsigned int channel)
142 {
143 	struct hpdi_private *devpriv = dev->private;
144 	struct comedi_subdevice *s = dev->read_subdev;
145 	struct comedi_cmd *cmd = &s->async->cmd;
146 	unsigned int idx;
147 	unsigned int start;
148 	unsigned int desc;
149 	unsigned int size;
150 	unsigned int next;
151 
152 	next = readl(devpriv->plx9080_mmio + PLX_REG_DMAPADR(channel));
153 
154 	idx = devpriv->dma_desc_index;
155 	start = le32_to_cpu(devpriv->dma_desc[idx].pci_start_addr);
156 	/* loop until we have read all the full buffers */
157 	for (desc = 0; (next < start || next >= start + devpriv->block_size) &&
158 	     desc < devpriv->num_dma_descriptors; desc++) {
159 		/* transfer data from dma buffer to comedi buffer */
160 		size = devpriv->block_size / sizeof(u32);
161 		if (cmd->stop_src == TRIG_COUNT) {
162 			if (size > devpriv->dio_count)
163 				size = devpriv->dio_count;
164 			devpriv->dio_count -= size;
165 		}
166 		comedi_buf_write_samples(s, devpriv->desc_dio_buffer[idx],
167 					 size);
168 		idx++;
169 		idx %= devpriv->num_dma_descriptors;
170 		start = le32_to_cpu(devpriv->dma_desc[idx].pci_start_addr);
171 
172 		devpriv->dma_desc_index = idx;
173 	}
174 	/* XXX check for buffer overrun somehow */
175 }
176 
gsc_hpdi_interrupt(int irq,void * d)177 static irqreturn_t gsc_hpdi_interrupt(int irq, void *d)
178 {
179 	struct comedi_device *dev = d;
180 	struct hpdi_private *devpriv = dev->private;
181 	struct comedi_subdevice *s = dev->read_subdev;
182 	struct comedi_async *async = s->async;
183 	u32 hpdi_intr_status, hpdi_board_status;
184 	u32 plx_status;
185 	u32 plx_bits;
186 	u8 dma0_status, dma1_status;
187 	unsigned long flags;
188 
189 	if (!dev->attached)
190 		return IRQ_NONE;
191 
192 	plx_status = readl(devpriv->plx9080_mmio + PLX_REG_INTCSR);
193 	if ((plx_status &
194 	     (PLX_INTCSR_DMA0IA | PLX_INTCSR_DMA1IA | PLX_INTCSR_PLIA)) == 0)
195 		return IRQ_NONE;
196 
197 	hpdi_intr_status = readl(dev->mmio + INTERRUPT_STATUS_REG);
198 	hpdi_board_status = readl(dev->mmio + BOARD_STATUS_REG);
199 
200 	if (hpdi_intr_status)
201 		writel(hpdi_intr_status, dev->mmio + INTERRUPT_STATUS_REG);
202 
203 	/* spin lock makes sure no one else changes plx dma control reg */
204 	spin_lock_irqsave(&dev->spinlock, flags);
205 	dma0_status = readb(devpriv->plx9080_mmio + PLX_REG_DMACSR0);
206 	if (plx_status & PLX_INTCSR_DMA0IA) {
207 		/* dma chan 0 interrupt */
208 		writeb((dma0_status & PLX_DMACSR_ENABLE) | PLX_DMACSR_CLEARINTR,
209 		       devpriv->plx9080_mmio + PLX_REG_DMACSR0);
210 
211 		if (dma0_status & PLX_DMACSR_ENABLE)
212 			gsc_hpdi_drain_dma(dev, 0);
213 	}
214 	spin_unlock_irqrestore(&dev->spinlock, flags);
215 
216 	/* spin lock makes sure no one else changes plx dma control reg */
217 	spin_lock_irqsave(&dev->spinlock, flags);
218 	dma1_status = readb(devpriv->plx9080_mmio + PLX_REG_DMACSR1);
219 	if (plx_status & PLX_INTCSR_DMA1IA) {
220 		/* XXX */ /* dma chan 1 interrupt */
221 		writeb((dma1_status & PLX_DMACSR_ENABLE) | PLX_DMACSR_CLEARINTR,
222 		       devpriv->plx9080_mmio + PLX_REG_DMACSR1);
223 	}
224 	spin_unlock_irqrestore(&dev->spinlock, flags);
225 
226 	/* clear possible plx9080 interrupt sources */
227 	if (plx_status & PLX_INTCSR_LDBIA) {
228 		/* clear local doorbell interrupt */
229 		plx_bits = readl(devpriv->plx9080_mmio + PLX_REG_L2PDBELL);
230 		writel(plx_bits, devpriv->plx9080_mmio + PLX_REG_L2PDBELL);
231 	}
232 
233 	if (hpdi_board_status & RX_OVERRUN_BIT) {
234 		dev_err(dev->class_dev, "rx fifo overrun\n");
235 		async->events |= COMEDI_CB_ERROR;
236 	}
237 
238 	if (hpdi_board_status & RX_UNDERRUN_BIT) {
239 		dev_err(dev->class_dev, "rx fifo underrun\n");
240 		async->events |= COMEDI_CB_ERROR;
241 	}
242 
243 	if (devpriv->dio_count == 0)
244 		async->events |= COMEDI_CB_EOA;
245 
246 	comedi_handle_events(dev, s);
247 
248 	return IRQ_HANDLED;
249 }
250 
gsc_hpdi_abort_dma(struct comedi_device * dev,unsigned int channel)251 static void gsc_hpdi_abort_dma(struct comedi_device *dev, unsigned int channel)
252 {
253 	struct hpdi_private *devpriv = dev->private;
254 	unsigned long flags;
255 
256 	/* spinlock for plx dma control/status reg */
257 	spin_lock_irqsave(&dev->spinlock, flags);
258 
259 	plx9080_abort_dma(devpriv->plx9080_mmio, channel);
260 
261 	spin_unlock_irqrestore(&dev->spinlock, flags);
262 }
263 
gsc_hpdi_cancel(struct comedi_device * dev,struct comedi_subdevice * s)264 static int gsc_hpdi_cancel(struct comedi_device *dev,
265 			   struct comedi_subdevice *s)
266 {
267 	writel(0, dev->mmio + BOARD_CONTROL_REG);
268 	writel(0, dev->mmio + INTERRUPT_CONTROL_REG);
269 
270 	gsc_hpdi_abort_dma(dev, 0);
271 
272 	return 0;
273 }
274 
gsc_hpdi_cmd(struct comedi_device * dev,struct comedi_subdevice * s)275 static int gsc_hpdi_cmd(struct comedi_device *dev,
276 			struct comedi_subdevice *s)
277 {
278 	struct hpdi_private *devpriv = dev->private;
279 	struct comedi_async *async = s->async;
280 	struct comedi_cmd *cmd = &async->cmd;
281 	unsigned long flags;
282 	u32 bits;
283 
284 	if (s->io_bits)
285 		return -EINVAL;
286 
287 	writel(RX_FIFO_RESET_BIT, dev->mmio + BOARD_CONTROL_REG);
288 
289 	gsc_hpdi_abort_dma(dev, 0);
290 
291 	devpriv->dma_desc_index = 0;
292 
293 	/*
294 	 * These register are supposedly unused during chained dma,
295 	 * but I have found that left over values from last operation
296 	 * occasionally cause problems with transfer of first dma
297 	 * block.  Initializing them to zero seems to fix the problem.
298 	 */
299 	writel(0, devpriv->plx9080_mmio + PLX_REG_DMASIZ0);
300 	writel(0, devpriv->plx9080_mmio + PLX_REG_DMAPADR0);
301 	writel(0, devpriv->plx9080_mmio + PLX_REG_DMALADR0);
302 
303 	/* give location of first dma descriptor */
304 	bits = devpriv->dma_desc_phys_addr | PLX_DMADPR_DESCPCI |
305 	       PLX_DMADPR_TCINTR | PLX_DMADPR_XFERL2P;
306 	writel(bits, devpriv->plx9080_mmio + PLX_REG_DMADPR0);
307 
308 	/* enable dma transfer */
309 	spin_lock_irqsave(&dev->spinlock, flags);
310 	writeb(PLX_DMACSR_ENABLE | PLX_DMACSR_START | PLX_DMACSR_CLEARINTR,
311 	       devpriv->plx9080_mmio + PLX_REG_DMACSR0);
312 	spin_unlock_irqrestore(&dev->spinlock, flags);
313 
314 	if (cmd->stop_src == TRIG_COUNT)
315 		devpriv->dio_count = cmd->stop_arg;
316 	else
317 		devpriv->dio_count = 1;
318 
319 	/* clear over/under run status flags */
320 	writel(RX_UNDERRUN_BIT | RX_OVERRUN_BIT, dev->mmio + BOARD_STATUS_REG);
321 
322 	/* enable interrupts */
323 	writel(RX_FULL_INTR, dev->mmio + INTERRUPT_CONTROL_REG);
324 
325 	writel(RX_ENABLE_BIT, dev->mmio + BOARD_CONTROL_REG);
326 
327 	return 0;
328 }
329 
gsc_hpdi_check_chanlist(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_cmd * cmd)330 static int gsc_hpdi_check_chanlist(struct comedi_device *dev,
331 				   struct comedi_subdevice *s,
332 				   struct comedi_cmd *cmd)
333 {
334 	int i;
335 
336 	for (i = 0; i < cmd->chanlist_len; i++) {
337 		unsigned int chan = CR_CHAN(cmd->chanlist[i]);
338 
339 		if (chan != i) {
340 			dev_dbg(dev->class_dev,
341 				"chanlist must be ch 0 to 31 in order\n");
342 			return -EINVAL;
343 		}
344 	}
345 
346 	return 0;
347 }
348 
gsc_hpdi_cmd_test(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_cmd * cmd)349 static int gsc_hpdi_cmd_test(struct comedi_device *dev,
350 			     struct comedi_subdevice *s,
351 			     struct comedi_cmd *cmd)
352 {
353 	int err = 0;
354 
355 	if (s->io_bits)
356 		return -EINVAL;
357 
358 	/* Step 1 : check if triggers are trivially valid */
359 
360 	err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW);
361 	err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_EXT);
362 	err |= comedi_check_trigger_src(&cmd->convert_src, TRIG_NOW);
363 	err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
364 	err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
365 
366 	if (err)
367 		return 1;
368 
369 	/* Step 2a : make sure trigger sources are unique */
370 
371 	err |= comedi_check_trigger_is_unique(cmd->stop_src);
372 
373 	/* Step 2b : and mutually compatible */
374 
375 	if (err)
376 		return 2;
377 
378 	/* Step 3: check if arguments are trivially valid */
379 
380 	err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
381 
382 	if (!cmd->chanlist_len || !cmd->chanlist) {
383 		cmd->chanlist_len = 32;
384 		err |= -EINVAL;
385 	}
386 	err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
387 					   cmd->chanlist_len);
388 
389 	if (cmd->stop_src == TRIG_COUNT)
390 		err |= comedi_check_trigger_arg_min(&cmd->stop_arg, 1);
391 	else	/* TRIG_NONE */
392 		err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
393 
394 	if (err)
395 		return 3;
396 
397 	/* Step 4: fix up any arguments */
398 
399 	/* Step 5: check channel list if it exists */
400 
401 	if (cmd->chanlist && cmd->chanlist_len > 0)
402 		err |= gsc_hpdi_check_chanlist(dev, s, cmd);
403 
404 	if (err)
405 		return 5;
406 
407 	return 0;
408 }
409 
410 /* setup dma descriptors so a link completes every 'len' bytes */
gsc_hpdi_setup_dma_descriptors(struct comedi_device * dev,unsigned int len)411 static int gsc_hpdi_setup_dma_descriptors(struct comedi_device *dev,
412 					  unsigned int len)
413 {
414 	struct hpdi_private *devpriv = dev->private;
415 	dma_addr_t phys_addr = devpriv->dma_desc_phys_addr;
416 	u32 next_bits = PLX_DMADPR_DESCPCI | PLX_DMADPR_TCINTR |
417 			PLX_DMADPR_XFERL2P;
418 	unsigned int offset = 0;
419 	unsigned int idx = 0;
420 	unsigned int i;
421 
422 	if (len > DMA_BUFFER_SIZE)
423 		len = DMA_BUFFER_SIZE;
424 	len -= len % sizeof(u32);
425 	if (len == 0)
426 		return -EINVAL;
427 
428 	for (i = 0; i < NUM_DMA_DESCRIPTORS && idx < NUM_DMA_BUFFERS; i++) {
429 		devpriv->dma_desc[i].pci_start_addr =
430 		    cpu_to_le32(devpriv->dio_buffer_phys_addr[idx] + offset);
431 		devpriv->dma_desc[i].local_start_addr = cpu_to_le32(FIFO_REG);
432 		devpriv->dma_desc[i].transfer_size = cpu_to_le32(len);
433 		devpriv->dma_desc[i].next = cpu_to_le32((phys_addr +
434 			(i + 1) * sizeof(devpriv->dma_desc[0])) | next_bits);
435 
436 		devpriv->desc_dio_buffer[i] = devpriv->dio_buffer[idx] +
437 					      (offset / sizeof(u32));
438 
439 		offset += len;
440 		if (len + offset > DMA_BUFFER_SIZE) {
441 			offset = 0;
442 			idx++;
443 		}
444 	}
445 	devpriv->num_dma_descriptors = i;
446 	/* fix last descriptor to point back to first */
447 	devpriv->dma_desc[i - 1].next = cpu_to_le32(phys_addr | next_bits);
448 
449 	devpriv->block_size = len;
450 
451 	return len;
452 }
453 
gsc_hpdi_dio_insn_config(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)454 static int gsc_hpdi_dio_insn_config(struct comedi_device *dev,
455 				    struct comedi_subdevice *s,
456 				    struct comedi_insn *insn,
457 				    unsigned int *data)
458 {
459 	int ret;
460 
461 	switch (data[0]) {
462 	case INSN_CONFIG_BLOCK_SIZE:
463 		ret = gsc_hpdi_setup_dma_descriptors(dev, data[1]);
464 		if (ret)
465 			return ret;
466 
467 		data[1] = ret;
468 		break;
469 	default:
470 		ret = comedi_dio_insn_config(dev, s, insn, data, 0xffffffff);
471 		if (ret)
472 			return ret;
473 		break;
474 	}
475 
476 	return insn->n;
477 }
478 
gsc_hpdi_free_dma(struct comedi_device * dev)479 static void gsc_hpdi_free_dma(struct comedi_device *dev)
480 {
481 	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
482 	struct hpdi_private *devpriv = dev->private;
483 	int i;
484 
485 	if (!devpriv)
486 		return;
487 
488 	/* free pci dma buffers */
489 	for (i = 0; i < NUM_DMA_BUFFERS; i++) {
490 		if (devpriv->dio_buffer[i])
491 			dma_free_coherent(&pcidev->dev,
492 					  DMA_BUFFER_SIZE,
493 					  devpriv->dio_buffer[i],
494 					  devpriv->dio_buffer_phys_addr[i]);
495 	}
496 	/* free dma descriptors */
497 	if (devpriv->dma_desc)
498 		dma_free_coherent(&pcidev->dev,
499 				  sizeof(struct plx_dma_desc) *
500 				  NUM_DMA_DESCRIPTORS,
501 				  devpriv->dma_desc,
502 				  devpriv->dma_desc_phys_addr);
503 }
504 
gsc_hpdi_init(struct comedi_device * dev)505 static int gsc_hpdi_init(struct comedi_device *dev)
506 {
507 	struct hpdi_private *devpriv = dev->private;
508 	u32 plx_intcsr_bits;
509 
510 	/* wait 10usec after reset before accessing fifos */
511 	writel(BOARD_RESET_BIT, dev->mmio + BOARD_CONTROL_REG);
512 	usleep_range(10, 1000);
513 
514 	writel(ALMOST_EMPTY_BITS(32) | ALMOST_FULL_BITS(32),
515 	       dev->mmio + RX_PROG_ALMOST_REG);
516 	writel(ALMOST_EMPTY_BITS(32) | ALMOST_FULL_BITS(32),
517 	       dev->mmio + TX_PROG_ALMOST_REG);
518 
519 	devpriv->tx_fifo_size = readl(dev->mmio + TX_FIFO_SIZE_REG) &
520 				FIFO_SIZE_MASK;
521 	devpriv->rx_fifo_size = readl(dev->mmio + RX_FIFO_SIZE_REG) &
522 				FIFO_SIZE_MASK;
523 
524 	writel(0, dev->mmio + INTERRUPT_CONTROL_REG);
525 
526 	/* enable interrupts */
527 	plx_intcsr_bits =
528 	    PLX_INTCSR_LSEABORTEN | PLX_INTCSR_LSEPARITYEN | PLX_INTCSR_PIEN |
529 	    PLX_INTCSR_PLIEN | PLX_INTCSR_PABORTIEN | PLX_INTCSR_LIOEN |
530 	    PLX_INTCSR_DMA0IEN;
531 	writel(plx_intcsr_bits, devpriv->plx9080_mmio + PLX_REG_INTCSR);
532 
533 	return 0;
534 }
535 
gsc_hpdi_init_plx9080(struct comedi_device * dev)536 static void gsc_hpdi_init_plx9080(struct comedi_device *dev)
537 {
538 	struct hpdi_private *devpriv = dev->private;
539 	u32 bits;
540 	void __iomem *plx_iobase = devpriv->plx9080_mmio;
541 
542 #ifdef __BIG_ENDIAN
543 	bits = PLX_BIGEND_DMA0 | PLX_BIGEND_DMA1;
544 #else
545 	bits = 0;
546 #endif
547 	writel(bits, devpriv->plx9080_mmio + PLX_REG_BIGEND);
548 
549 	writel(0, devpriv->plx9080_mmio + PLX_REG_INTCSR);
550 
551 	gsc_hpdi_abort_dma(dev, 0);
552 	gsc_hpdi_abort_dma(dev, 1);
553 
554 	/* configure dma0 mode */
555 	bits = 0;
556 	/* enable ready input */
557 	bits |= PLX_DMAMODE_READYIEN;
558 	/* enable dma chaining */
559 	bits |= PLX_DMAMODE_CHAINEN;
560 	/*
561 	 * enable interrupt on dma done
562 	 * (probably don't need this, since chain never finishes)
563 	 */
564 	bits |= PLX_DMAMODE_DONEIEN;
565 	/*
566 	 * don't increment local address during transfers
567 	 * (we are transferring from a fixed fifo register)
568 	 */
569 	bits |= PLX_DMAMODE_LACONST;
570 	/* route dma interrupt to pci bus */
571 	bits |= PLX_DMAMODE_INTRPCI;
572 	/* enable demand mode */
573 	bits |= PLX_DMAMODE_DEMAND;
574 	/* enable local burst mode */
575 	bits |= PLX_DMAMODE_BURSTEN;
576 	bits |= PLX_DMAMODE_WIDTH_32;
577 	writel(bits, plx_iobase + PLX_REG_DMAMODE0);
578 }
579 
gsc_hpdi_auto_attach(struct comedi_device * dev,unsigned long context_unused)580 static int gsc_hpdi_auto_attach(struct comedi_device *dev,
581 				unsigned long context_unused)
582 {
583 	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
584 	struct hpdi_private *devpriv;
585 	struct comedi_subdevice *s;
586 	int i;
587 	int retval;
588 
589 	dev->board_name = "pci-hpdi32";
590 
591 	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
592 	if (!devpriv)
593 		return -ENOMEM;
594 
595 	retval = comedi_pci_enable(dev);
596 	if (retval)
597 		return retval;
598 	pci_set_master(pcidev);
599 
600 	devpriv->plx9080_mmio = pci_ioremap_bar(pcidev, 0);
601 	dev->mmio = pci_ioremap_bar(pcidev, 2);
602 	if (!devpriv->plx9080_mmio || !dev->mmio) {
603 		dev_warn(dev->class_dev, "failed to remap io memory\n");
604 		return -ENOMEM;
605 	}
606 
607 	gsc_hpdi_init_plx9080(dev);
608 
609 	/* get irq */
610 	if (request_irq(pcidev->irq, gsc_hpdi_interrupt, IRQF_SHARED,
611 			dev->board_name, dev)) {
612 		dev_warn(dev->class_dev,
613 			 "unable to allocate irq %u\n", pcidev->irq);
614 		return -EINVAL;
615 	}
616 	dev->irq = pcidev->irq;
617 
618 	dev_dbg(dev->class_dev, " irq %u\n", dev->irq);
619 
620 	/* allocate pci dma buffers */
621 	for (i = 0; i < NUM_DMA_BUFFERS; i++) {
622 		devpriv->dio_buffer[i] =
623 		    dma_alloc_coherent(&pcidev->dev, DMA_BUFFER_SIZE,
624 				       &devpriv->dio_buffer_phys_addr[i],
625 				       GFP_KERNEL);
626 		if (!devpriv->dio_buffer[i]) {
627 			dev_warn(dev->class_dev,
628 				 "failed to allocate DMA buffer\n");
629 			return -ENOMEM;
630 		}
631 	}
632 	/* allocate dma descriptors */
633 	devpriv->dma_desc = dma_alloc_coherent(&pcidev->dev,
634 					       sizeof(struct plx_dma_desc) *
635 					       NUM_DMA_DESCRIPTORS,
636 					       &devpriv->dma_desc_phys_addr,
637 					       GFP_KERNEL);
638 	if (!devpriv->dma_desc) {
639 		dev_warn(dev->class_dev,
640 			 "failed to allocate DMA descriptors\n");
641 		return -ENOMEM;
642 	}
643 	if (devpriv->dma_desc_phys_addr & 0xf) {
644 		dev_warn(dev->class_dev,
645 			 " dma descriptors not quad-word aligned (bug)\n");
646 		return -EIO;
647 	}
648 
649 	retval = gsc_hpdi_setup_dma_descriptors(dev, 0x1000);
650 	if (retval < 0)
651 		return retval;
652 
653 	retval = comedi_alloc_subdevices(dev, 1);
654 	if (retval)
655 		return retval;
656 
657 	/* Digital I/O subdevice */
658 	s = &dev->subdevices[0];
659 	dev->read_subdev = s;
660 	s->type		= COMEDI_SUBD_DIO;
661 	s->subdev_flags	= SDF_READABLE | SDF_WRITABLE | SDF_LSAMPL |
662 			  SDF_CMD_READ;
663 	s->n_chan	= 32;
664 	s->len_chanlist	= 32;
665 	s->maxdata	= 1;
666 	s->range_table	= &range_digital;
667 	s->insn_config	= gsc_hpdi_dio_insn_config;
668 	s->do_cmd	= gsc_hpdi_cmd;
669 	s->do_cmdtest	= gsc_hpdi_cmd_test;
670 	s->cancel	= gsc_hpdi_cancel;
671 
672 	return gsc_hpdi_init(dev);
673 }
674 
gsc_hpdi_detach(struct comedi_device * dev)675 static void gsc_hpdi_detach(struct comedi_device *dev)
676 {
677 	struct hpdi_private *devpriv = dev->private;
678 
679 	if (dev->irq)
680 		free_irq(dev->irq, dev);
681 	if (devpriv) {
682 		if (devpriv->plx9080_mmio) {
683 			writel(0, devpriv->plx9080_mmio + PLX_REG_INTCSR);
684 			iounmap(devpriv->plx9080_mmio);
685 		}
686 		if (dev->mmio)
687 			iounmap(dev->mmio);
688 	}
689 	comedi_pci_disable(dev);
690 	gsc_hpdi_free_dma(dev);
691 }
692 
693 static struct comedi_driver gsc_hpdi_driver = {
694 	.driver_name	= "gsc_hpdi",
695 	.module		= THIS_MODULE,
696 	.auto_attach	= gsc_hpdi_auto_attach,
697 	.detach		= gsc_hpdi_detach,
698 };
699 
gsc_hpdi_pci_probe(struct pci_dev * dev,const struct pci_device_id * id)700 static int gsc_hpdi_pci_probe(struct pci_dev *dev,
701 			      const struct pci_device_id *id)
702 {
703 	return comedi_pci_auto_config(dev, &gsc_hpdi_driver, id->driver_data);
704 }
705 
706 static const struct pci_device_id gsc_hpdi_pci_table[] = {
707 	{ PCI_DEVICE_SUB(PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9080,
708 			 PCI_VENDOR_ID_PLX, 0x2400) },
709 	{ 0 }
710 };
711 MODULE_DEVICE_TABLE(pci, gsc_hpdi_pci_table);
712 
713 static struct pci_driver gsc_hpdi_pci_driver = {
714 	.name		= "gsc_hpdi",
715 	.id_table	= gsc_hpdi_pci_table,
716 	.probe		= gsc_hpdi_pci_probe,
717 	.remove		= comedi_pci_auto_unconfig,
718 };
719 module_comedi_pci_driver(gsc_hpdi_driver, gsc_hpdi_pci_driver);
720 
721 MODULE_AUTHOR("Comedi https://www.comedi.org");
722 MODULE_DESCRIPTION("Comedi driver for General Standards PCI-HPDI32/PMC-HPDI32");
723 MODULE_LICENSE("GPL");
724