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
43enum {
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
107typedef enum { adma_state_idle, adma_state_pkt, adma_state_mmio } adma_state_t;
108
109struct adma_port_priv {
110	u8			*pkt;
111	dma_addr_t		pkt_dma;
112	adma_state_t		state;
113};
114
115static int adma_ata_init_one(struct pci_dev *pdev,
116				const struct pci_device_id *ent);
117static int adma_port_start(struct ata_port *ap);
118static void adma_port_stop(struct ata_port *ap);
119static enum ata_completion_errors adma_qc_prep(struct ata_queued_cmd *qc);
120static unsigned int adma_qc_issue(struct ata_queued_cmd *qc);
121static int adma_check_atapi_dma(struct ata_queued_cmd *qc);
122static void adma_freeze(struct ata_port *ap);
123static void adma_thaw(struct ata_port *ap);
124static int adma_prereset(struct ata_link *link, unsigned long deadline);
125
126static const 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
132static 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
149static 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
159static const struct pci_device_id adma_ata_pci_tbl[] = {
160	{ PCI_VDEVICE(PDC, 0x1841), board_1841_idx },
161
162	{ }	/* terminate list */
163};
164
165static 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
172static int adma_check_atapi_dma(struct ata_queued_cmd *qc)
173{
174	return 1;	/* ATAPI DMA not yet supported */
175}
176
177static 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
188static 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
216static 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
224static 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
239static void adma_thaw(struct ata_port *ap)
240{
241	adma_reinit_engine(ap);
242}
243
244static 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
256static 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
295static 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
356static 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
365static 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
387static 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
437static 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
477static 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
489static 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
506static 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
530static void adma_port_stop(struct ata_port *ap)
531{
532	adma_reset_engine(ap);
533}
534
535static 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
547static 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
602module_pci_driver(adma_ata_pci_driver);
603
604MODULE_AUTHOR("Mark Lord");
605MODULE_DESCRIPTION("Pacific Digital Corporation ADMA low-level driver");
606MODULE_LICENSE("GPL");
607MODULE_DEVICE_TABLE(pci, adma_ata_pci_tbl);
608MODULE_VERSION(DRV_VERSION);
609