xref: /openbmc/linux/drivers/ata/pdc_adma.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  pdc_adma.c - Pacific Digital Corporation ADMA
4  *
5  *  Maintained by:  Tejun Heo <tj@kernel.org>
6  *
7  *  Copyright 2005 Mark Lord
8  *
9  *  libata documentation is available via 'make {ps|pdf}docs',
10  *  as Documentation/driver-api/libata.rst
11  *
12  *  Supports ATA disks in single-packet ADMA mode.
13  *  Uses PIO for everything else.
14  *
15  *  TODO:  Use ADMA transfers for ATAPI devices, when possible.
16  *  This requires careful attention to a number of quirks of the chip.
17  */
18 
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/gfp.h>
22 #include <linux/pci.h>
23 #include <linux/blkdev.h>
24 #include <linux/delay.h>
25 #include <linux/interrupt.h>
26 #include <linux/device.h>
27 #include <scsi/scsi_host.h>
28 #include <linux/libata.h>
29 
30 #define DRV_NAME	"pdc_adma"
31 #define DRV_VERSION	"1.0"
32 
33 /* macro to calculate base address for ATA regs */
34 #define ADMA_ATA_REGS(base, port_no)	((base) + ((port_no) * 0x40))
35 
36 /* macro to calculate base address for ADMA regs */
37 #define ADMA_REGS(base, port_no)	((base) + 0x80 + ((port_no) * 0x20))
38 
39 /* macro to obtain addresses from ata_port */
40 #define ADMA_PORT_REGS(ap) \
41 	ADMA_REGS((ap)->host->iomap[ADMA_MMIO_BAR], ap->port_no)
42 
43 enum {
44 	ADMA_MMIO_BAR		= 4,
45 
46 	ADMA_PORTS		= 2,
47 	ADMA_CPB_BYTES		= 40,
48 	ADMA_PRD_BYTES		= LIBATA_MAX_PRD * 16,
49 	ADMA_PKT_BYTES		= ADMA_CPB_BYTES + ADMA_PRD_BYTES,
50 
51 	ADMA_DMA_BOUNDARY	= 0xffffffff,
52 
53 	/* global register offsets */
54 	ADMA_MODE_LOCK		= 0x00c7,
55 
56 	/* per-channel register offsets */
57 	ADMA_CONTROL		= 0x0000, /* ADMA control */
58 	ADMA_STATUS		= 0x0002, /* ADMA status */
59 	ADMA_CPB_COUNT		= 0x0004, /* CPB count */
60 	ADMA_CPB_CURRENT	= 0x000c, /* current CPB address */
61 	ADMA_CPB_NEXT		= 0x000c, /* next CPB address */
62 	ADMA_CPB_LOOKUP		= 0x0010, /* CPB lookup table */
63 	ADMA_FIFO_IN		= 0x0014, /* input FIFO threshold */
64 	ADMA_FIFO_OUT		= 0x0016, /* output FIFO threshold */
65 
66 	/* ADMA_CONTROL register bits */
67 	aNIEN			= (1 << 8), /* irq mask: 1==masked */
68 	aGO			= (1 << 7), /* packet trigger ("Go!") */
69 	aRSTADM			= (1 << 5), /* ADMA logic reset */
70 	aPIOMD4			= 0x0003,   /* PIO mode 4 */
71 
72 	/* ADMA_STATUS register bits */
73 	aPSD			= (1 << 6),
74 	aUIRQ			= (1 << 4),
75 	aPERR			= (1 << 0),
76 
77 	/* CPB bits */
78 	cDONE			= (1 << 0),
79 	cATERR			= (1 << 3),
80 
81 	cVLD			= (1 << 0),
82 	cDAT			= (1 << 2),
83 	cIEN			= (1 << 3),
84 
85 	/* PRD bits */
86 	pORD			= (1 << 4),
87 	pDIRO			= (1 << 5),
88 	pEND			= (1 << 7),
89 
90 	/* ATA register flags */
91 	rIGN			= (1 << 5),
92 	rEND			= (1 << 7),
93 
94 	/* ATA register addresses */
95 	ADMA_REGS_CONTROL	= 0x0e,
96 	ADMA_REGS_SECTOR_COUNT	= 0x12,
97 	ADMA_REGS_LBA_LOW	= 0x13,
98 	ADMA_REGS_LBA_MID	= 0x14,
99 	ADMA_REGS_LBA_HIGH	= 0x15,
100 	ADMA_REGS_DEVICE	= 0x16,
101 	ADMA_REGS_COMMAND	= 0x17,
102 
103 	/* PCI device IDs */
104 	board_1841_idx		= 0,	/* ADMA 2-port controller */
105 };
106 
107 typedef enum { adma_state_idle, adma_state_pkt, adma_state_mmio } adma_state_t;
108 
109 struct adma_port_priv {
110 	u8			*pkt;
111 	dma_addr_t		pkt_dma;
112 	adma_state_t		state;
113 };
114 
115 static int adma_ata_init_one(struct pci_dev *pdev,
116 				const struct pci_device_id *ent);
117 static int adma_port_start(struct ata_port *ap);
118 static void adma_port_stop(struct ata_port *ap);
119 static enum ata_completion_errors adma_qc_prep(struct ata_queued_cmd *qc);
120 static unsigned int adma_qc_issue(struct ata_queued_cmd *qc);
121 static int adma_check_atapi_dma(struct ata_queued_cmd *qc);
122 static void adma_freeze(struct ata_port *ap);
123 static void adma_thaw(struct ata_port *ap);
124 static int adma_prereset(struct ata_link *link, unsigned long deadline);
125 
126 static struct scsi_host_template adma_ata_sht = {
127 	ATA_BASE_SHT(DRV_NAME),
128 	.sg_tablesize		= LIBATA_MAX_PRD,
129 	.dma_boundary		= ADMA_DMA_BOUNDARY,
130 };
131 
132 static struct ata_port_operations adma_ata_ops = {
133 	.inherits		= &ata_sff_port_ops,
134 
135 	.lost_interrupt		= ATA_OP_NULL,
136 
137 	.check_atapi_dma	= adma_check_atapi_dma,
138 	.qc_prep		= adma_qc_prep,
139 	.qc_issue		= adma_qc_issue,
140 
141 	.freeze			= adma_freeze,
142 	.thaw			= adma_thaw,
143 	.prereset		= adma_prereset,
144 
145 	.port_start		= adma_port_start,
146 	.port_stop		= adma_port_stop,
147 };
148 
149 static struct ata_port_info adma_port_info[] = {
150 	/* board_1841_idx */
151 	{
152 		.flags		= ATA_FLAG_SLAVE_POSS | ATA_FLAG_PIO_POLLING,
153 		.pio_mask	= ATA_PIO4_ONLY,
154 		.udma_mask	= ATA_UDMA4,
155 		.port_ops	= &adma_ata_ops,
156 	},
157 };
158 
159 static const struct pci_device_id adma_ata_pci_tbl[] = {
160 	{ PCI_VDEVICE(PDC, 0x1841), board_1841_idx },
161 
162 	{ }	/* terminate list */
163 };
164 
165 static struct pci_driver adma_ata_pci_driver = {
166 	.name			= DRV_NAME,
167 	.id_table		= adma_ata_pci_tbl,
168 	.probe			= adma_ata_init_one,
169 	.remove			= ata_pci_remove_one,
170 };
171 
172 static int adma_check_atapi_dma(struct ata_queued_cmd *qc)
173 {
174 	return 1;	/* ATAPI DMA not yet supported */
175 }
176 
177 static void adma_reset_engine(struct ata_port *ap)
178 {
179 	void __iomem *chan = ADMA_PORT_REGS(ap);
180 
181 	/* reset ADMA to idle state */
182 	writew(aPIOMD4 | aNIEN | aRSTADM, chan + ADMA_CONTROL);
183 	udelay(2);
184 	writew(aPIOMD4, chan + ADMA_CONTROL);
185 	udelay(2);
186 }
187 
188 static void adma_reinit_engine(struct ata_port *ap)
189 {
190 	struct adma_port_priv *pp = ap->private_data;
191 	void __iomem *chan = ADMA_PORT_REGS(ap);
192 
193 	/* mask/clear ATA interrupts */
194 	writeb(ATA_NIEN, ap->ioaddr.ctl_addr);
195 	ata_sff_check_status(ap);
196 
197 	/* reset the ADMA engine */
198 	adma_reset_engine(ap);
199 
200 	/* set in-FIFO threshold to 0x100 */
201 	writew(0x100, chan + ADMA_FIFO_IN);
202 
203 	/* set CPB pointer */
204 	writel((u32)pp->pkt_dma, chan + ADMA_CPB_NEXT);
205 
206 	/* set out-FIFO threshold to 0x100 */
207 	writew(0x100, chan + ADMA_FIFO_OUT);
208 
209 	/* set CPB count */
210 	writew(1, chan + ADMA_CPB_COUNT);
211 
212 	/* read/discard ADMA status */
213 	readb(chan + ADMA_STATUS);
214 }
215 
216 static inline void adma_enter_reg_mode(struct ata_port *ap)
217 {
218 	void __iomem *chan = ADMA_PORT_REGS(ap);
219 
220 	writew(aPIOMD4, chan + ADMA_CONTROL);
221 	readb(chan + ADMA_STATUS);	/* flush */
222 }
223 
224 static void adma_freeze(struct ata_port *ap)
225 {
226 	void __iomem *chan = ADMA_PORT_REGS(ap);
227 
228 	/* mask/clear ATA interrupts */
229 	writeb(ATA_NIEN, ap->ioaddr.ctl_addr);
230 	ata_sff_check_status(ap);
231 
232 	/* reset ADMA to idle state */
233 	writew(aPIOMD4 | aNIEN | aRSTADM, chan + ADMA_CONTROL);
234 	udelay(2);
235 	writew(aPIOMD4 | aNIEN, chan + ADMA_CONTROL);
236 	udelay(2);
237 }
238 
239 static void adma_thaw(struct ata_port *ap)
240 {
241 	adma_reinit_engine(ap);
242 }
243 
244 static int adma_prereset(struct ata_link *link, unsigned long deadline)
245 {
246 	struct ata_port *ap = link->ap;
247 	struct adma_port_priv *pp = ap->private_data;
248 
249 	if (pp->state != adma_state_idle) /* healthy paranoia */
250 		pp->state = adma_state_mmio;
251 	adma_reinit_engine(ap);
252 
253 	return ata_sff_prereset(link, deadline);
254 }
255 
256 static int adma_fill_sg(struct ata_queued_cmd *qc)
257 {
258 	struct scatterlist *sg;
259 	struct ata_port *ap = qc->ap;
260 	struct adma_port_priv *pp = ap->private_data;
261 	u8  *buf = pp->pkt, *last_buf = NULL;
262 	int i = (2 + buf[3]) * 8;
263 	u8 pFLAGS = pORD | ((qc->tf.flags & ATA_TFLAG_WRITE) ? pDIRO : 0);
264 	unsigned int si;
265 
266 	for_each_sg(qc->sg, sg, qc->n_elem, si) {
267 		u32 addr;
268 		u32 len;
269 
270 		addr = (u32)sg_dma_address(sg);
271 		*(__le32 *)(buf + i) = cpu_to_le32(addr);
272 		i += 4;
273 
274 		len = sg_dma_len(sg) >> 3;
275 		*(__le32 *)(buf + i) = cpu_to_le32(len);
276 		i += 4;
277 
278 		last_buf = &buf[i];
279 		buf[i++] = pFLAGS;
280 		buf[i++] = qc->dev->dma_mode & 0xf;
281 		buf[i++] = 0;	/* pPKLW */
282 		buf[i++] = 0;	/* reserved */
283 
284 		*(__le32 *)(buf + i) =
285 			(pFLAGS & pEND) ? 0 : cpu_to_le32(pp->pkt_dma + i + 4);
286 		i += 4;
287 	}
288 
289 	if (likely(last_buf))
290 		*last_buf |= pEND;
291 
292 	return i;
293 }
294 
295 static enum ata_completion_errors adma_qc_prep(struct ata_queued_cmd *qc)
296 {
297 	struct adma_port_priv *pp = qc->ap->private_data;
298 	u8  *buf = pp->pkt;
299 	u32 pkt_dma = (u32)pp->pkt_dma;
300 	int i = 0;
301 
302 	adma_enter_reg_mode(qc->ap);
303 	if (qc->tf.protocol != ATA_PROT_DMA)
304 		return AC_ERR_OK;
305 
306 	buf[i++] = 0;	/* Response flags */
307 	buf[i++] = 0;	/* reserved */
308 	buf[i++] = cVLD | cDAT | cIEN;
309 	i++;		/* cLEN, gets filled in below */
310 
311 	*(__le32 *)(buf+i) = cpu_to_le32(pkt_dma);	/* cNCPB */
312 	i += 4;		/* cNCPB */
313 	i += 4;		/* cPRD, gets filled in below */
314 
315 	buf[i++] = 0;	/* reserved */
316 	buf[i++] = 0;	/* reserved */
317 	buf[i++] = 0;	/* reserved */
318 	buf[i++] = 0;	/* reserved */
319 
320 	/* ATA registers; must be a multiple of 4 */
321 	buf[i++] = qc->tf.device;
322 	buf[i++] = ADMA_REGS_DEVICE;
323 	if ((qc->tf.flags & ATA_TFLAG_LBA48)) {
324 		buf[i++] = qc->tf.hob_nsect;
325 		buf[i++] = ADMA_REGS_SECTOR_COUNT;
326 		buf[i++] = qc->tf.hob_lbal;
327 		buf[i++] = ADMA_REGS_LBA_LOW;
328 		buf[i++] = qc->tf.hob_lbam;
329 		buf[i++] = ADMA_REGS_LBA_MID;
330 		buf[i++] = qc->tf.hob_lbah;
331 		buf[i++] = ADMA_REGS_LBA_HIGH;
332 	}
333 	buf[i++] = qc->tf.nsect;
334 	buf[i++] = ADMA_REGS_SECTOR_COUNT;
335 	buf[i++] = qc->tf.lbal;
336 	buf[i++] = ADMA_REGS_LBA_LOW;
337 	buf[i++] = qc->tf.lbam;
338 	buf[i++] = ADMA_REGS_LBA_MID;
339 	buf[i++] = qc->tf.lbah;
340 	buf[i++] = ADMA_REGS_LBA_HIGH;
341 	buf[i++] = 0;
342 	buf[i++] = ADMA_REGS_CONTROL;
343 	buf[i++] = rIGN;
344 	buf[i++] = 0;
345 	buf[i++] = qc->tf.command;
346 	buf[i++] = ADMA_REGS_COMMAND | rEND;
347 
348 	buf[3] = (i >> 3) - 2;				/* cLEN */
349 	*(__le32 *)(buf+8) = cpu_to_le32(pkt_dma + i);	/* cPRD */
350 
351 	i = adma_fill_sg(qc);
352 	wmb();	/* flush PRDs and pkt to memory */
353 	return AC_ERR_OK;
354 }
355 
356 static inline void adma_packet_start(struct ata_queued_cmd *qc)
357 {
358 	struct ata_port *ap = qc->ap;
359 	void __iomem *chan = ADMA_PORT_REGS(ap);
360 
361 	/* fire up the ADMA engine */
362 	writew(aPIOMD4 | aGO, chan + ADMA_CONTROL);
363 }
364 
365 static unsigned int adma_qc_issue(struct ata_queued_cmd *qc)
366 {
367 	struct adma_port_priv *pp = qc->ap->private_data;
368 
369 	switch (qc->tf.protocol) {
370 	case ATA_PROT_DMA:
371 		pp->state = adma_state_pkt;
372 		adma_packet_start(qc);
373 		return 0;
374 
375 	case ATAPI_PROT_DMA:
376 		BUG();
377 		break;
378 
379 	default:
380 		break;
381 	}
382 
383 	pp->state = adma_state_mmio;
384 	return ata_sff_qc_issue(qc);
385 }
386 
387 static inline unsigned int adma_intr_pkt(struct ata_host *host)
388 {
389 	unsigned int handled = 0, port_no;
390 
391 	for (port_no = 0; port_no < host->n_ports; ++port_no) {
392 		struct ata_port *ap = host->ports[port_no];
393 		struct adma_port_priv *pp;
394 		struct ata_queued_cmd *qc;
395 		void __iomem *chan = ADMA_PORT_REGS(ap);
396 		u8 status = readb(chan + ADMA_STATUS);
397 
398 		if (status == 0)
399 			continue;
400 		handled = 1;
401 		adma_enter_reg_mode(ap);
402 		pp = ap->private_data;
403 		if (!pp || pp->state != adma_state_pkt)
404 			continue;
405 		qc = ata_qc_from_tag(ap, ap->link.active_tag);
406 		if (qc && (!(qc->tf.flags & ATA_TFLAG_POLLING))) {
407 			if (status & aPERR)
408 				qc->err_mask |= AC_ERR_HOST_BUS;
409 			else if ((status & (aPSD | aUIRQ)))
410 				qc->err_mask |= AC_ERR_OTHER;
411 
412 			if (pp->pkt[0] & cATERR)
413 				qc->err_mask |= AC_ERR_DEV;
414 			else if (pp->pkt[0] != cDONE)
415 				qc->err_mask |= AC_ERR_OTHER;
416 
417 			if (!qc->err_mask)
418 				ata_qc_complete(qc);
419 			else {
420 				struct ata_eh_info *ehi = &ap->link.eh_info;
421 				ata_ehi_clear_desc(ehi);
422 				ata_ehi_push_desc(ehi,
423 					"ADMA-status 0x%02X", status);
424 				ata_ehi_push_desc(ehi,
425 					"pkt[0] 0x%02X", pp->pkt[0]);
426 
427 				if (qc->err_mask == AC_ERR_DEV)
428 					ata_port_abort(ap);
429 				else
430 					ata_port_freeze(ap);
431 			}
432 		}
433 	}
434 	return handled;
435 }
436 
437 static inline unsigned int adma_intr_mmio(struct ata_host *host)
438 {
439 	unsigned int handled = 0, port_no;
440 
441 	for (port_no = 0; port_no < host->n_ports; ++port_no) {
442 		struct ata_port *ap = host->ports[port_no];
443 		struct adma_port_priv *pp = ap->private_data;
444 		struct ata_queued_cmd *qc;
445 
446 		if (!pp || pp->state != adma_state_mmio)
447 			continue;
448 		qc = ata_qc_from_tag(ap, ap->link.active_tag);
449 		if (qc && (!(qc->tf.flags & ATA_TFLAG_POLLING))) {
450 
451 			/* check main status, clearing INTRQ */
452 			u8 status = ata_sff_check_status(ap);
453 			if ((status & ATA_BUSY))
454 				continue;
455 
456 			/* complete taskfile transaction */
457 			pp->state = adma_state_idle;
458 			qc->err_mask |= ac_err_mask(status);
459 			if (!qc->err_mask)
460 				ata_qc_complete(qc);
461 			else {
462 				struct ata_eh_info *ehi = &ap->link.eh_info;
463 				ata_ehi_clear_desc(ehi);
464 				ata_ehi_push_desc(ehi, "status 0x%02X", status);
465 
466 				if (qc->err_mask == AC_ERR_DEV)
467 					ata_port_abort(ap);
468 				else
469 					ata_port_freeze(ap);
470 			}
471 			handled = 1;
472 		}
473 	}
474 	return handled;
475 }
476 
477 static irqreturn_t adma_intr(int irq, void *dev_instance)
478 {
479 	struct ata_host *host = dev_instance;
480 	unsigned int handled = 0;
481 
482 	spin_lock(&host->lock);
483 	handled  = adma_intr_pkt(host) | adma_intr_mmio(host);
484 	spin_unlock(&host->lock);
485 
486 	return IRQ_RETVAL(handled);
487 }
488 
489 static void adma_ata_setup_port(struct ata_ioports *port, void __iomem *base)
490 {
491 	port->cmd_addr		=
492 	port->data_addr		= base + 0x000;
493 	port->error_addr	=
494 	port->feature_addr	= base + 0x004;
495 	port->nsect_addr	= base + 0x008;
496 	port->lbal_addr		= base + 0x00c;
497 	port->lbam_addr		= base + 0x010;
498 	port->lbah_addr		= base + 0x014;
499 	port->device_addr	= base + 0x018;
500 	port->status_addr	=
501 	port->command_addr	= base + 0x01c;
502 	port->altstatus_addr	=
503 	port->ctl_addr		= base + 0x038;
504 }
505 
506 static int adma_port_start(struct ata_port *ap)
507 {
508 	struct device *dev = ap->host->dev;
509 	struct adma_port_priv *pp;
510 
511 	adma_enter_reg_mode(ap);
512 	pp = devm_kzalloc(dev, sizeof(*pp), GFP_KERNEL);
513 	if (!pp)
514 		return -ENOMEM;
515 	pp->pkt = dmam_alloc_coherent(dev, ADMA_PKT_BYTES, &pp->pkt_dma,
516 				      GFP_KERNEL);
517 	if (!pp->pkt)
518 		return -ENOMEM;
519 	/* paranoia? */
520 	if ((pp->pkt_dma & 7) != 0) {
521 		ata_port_err(ap, "bad alignment for pp->pkt_dma: %08x\n",
522 			     (u32)pp->pkt_dma);
523 		return -ENOMEM;
524 	}
525 	ap->private_data = pp;
526 	adma_reinit_engine(ap);
527 	return 0;
528 }
529 
530 static void adma_port_stop(struct ata_port *ap)
531 {
532 	adma_reset_engine(ap);
533 }
534 
535 static void adma_host_init(struct ata_host *host, unsigned int chip_id)
536 {
537 	unsigned int port_no;
538 
539 	/* enable/lock aGO operation */
540 	writeb(7, host->iomap[ADMA_MMIO_BAR] + ADMA_MODE_LOCK);
541 
542 	/* reset the ADMA logic */
543 	for (port_no = 0; port_no < ADMA_PORTS; ++port_no)
544 		adma_reset_engine(host->ports[port_no]);
545 }
546 
547 static int adma_ata_init_one(struct pci_dev *pdev,
548 			     const struct pci_device_id *ent)
549 {
550 	unsigned int board_idx = (unsigned int) ent->driver_data;
551 	const struct ata_port_info *ppi[] = { &adma_port_info[board_idx], NULL };
552 	struct ata_host *host;
553 	void __iomem *mmio_base;
554 	int rc, port_no;
555 
556 	ata_print_version_once(&pdev->dev, DRV_VERSION);
557 
558 	/* alloc host */
559 	host = ata_host_alloc_pinfo(&pdev->dev, ppi, ADMA_PORTS);
560 	if (!host)
561 		return -ENOMEM;
562 
563 	/* acquire resources and fill host */
564 	rc = pcim_enable_device(pdev);
565 	if (rc)
566 		return rc;
567 
568 	if ((pci_resource_flags(pdev, 4) & IORESOURCE_MEM) == 0)
569 		return -ENODEV;
570 
571 	rc = pcim_iomap_regions(pdev, 1 << ADMA_MMIO_BAR, DRV_NAME);
572 	if (rc)
573 		return rc;
574 	host->iomap = pcim_iomap_table(pdev);
575 	mmio_base = host->iomap[ADMA_MMIO_BAR];
576 
577 	rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
578 	if (rc) {
579 		dev_err(&pdev->dev, "32-bit DMA enable failed\n");
580 		return rc;
581 	}
582 
583 	for (port_no = 0; port_no < ADMA_PORTS; ++port_no) {
584 		struct ata_port *ap = host->ports[port_no];
585 		void __iomem *port_base = ADMA_ATA_REGS(mmio_base, port_no);
586 		unsigned int offset = port_base - mmio_base;
587 
588 		adma_ata_setup_port(&ap->ioaddr, port_base);
589 
590 		ata_port_pbar_desc(ap, ADMA_MMIO_BAR, -1, "mmio");
591 		ata_port_pbar_desc(ap, ADMA_MMIO_BAR, offset, "port");
592 	}
593 
594 	/* initialize adapter */
595 	adma_host_init(host, board_idx);
596 
597 	pci_set_master(pdev);
598 	return ata_host_activate(host, pdev->irq, adma_intr, IRQF_SHARED,
599 				 &adma_ata_sht);
600 }
601 
602 module_pci_driver(adma_ata_pci_driver);
603 
604 MODULE_AUTHOR("Mark Lord");
605 MODULE_DESCRIPTION("Pacific Digital Corporation ADMA low-level driver");
606 MODULE_LICENSE("GPL");
607 MODULE_DEVICE_TABLE(pci, adma_ata_pci_tbl);
608 MODULE_VERSION(DRV_VERSION);
609