1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ixp4xx PATA/Compact Flash driver
4 * Copyright (C) 2006-07 Tower Technologies
5 * Author: Alessandro Zummo <a.zummo@towertech.it>
6 *
7 * An ATA driver to handle a Compact Flash connected
8 * to the ixp4xx expansion bus in TrueIDE mode. The CF
9 * must have it chip selects connected to two CS lines
10 * on the ixp4xx. In the irq is not available, you might
11 * want to modify both this driver and libata to run in
12 * polling mode.
13 */
14
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/libata.h>
18#include <linux/irq.h>
19#include <linux/platform_device.h>
20#include <scsi/scsi_host.h>
21
22#define DRV_NAME	"pata_ixp4xx_cf"
23#define DRV_VERSION	"0.2"
24
25static int ixp4xx_set_mode(struct ata_link *link, struct ata_device **error)
26{
27	struct ata_device *dev;
28
29	ata_for_each_dev(dev, link, ENABLED) {
30		ata_dev_info(dev, "configured for PIO0\n");
31		dev->pio_mode = XFER_PIO_0;
32		dev->xfer_mode = XFER_PIO_0;
33		dev->xfer_shift = ATA_SHIFT_PIO;
34		dev->flags |= ATA_DFLAG_PIO;
35	}
36	return 0;
37}
38
39static unsigned int ixp4xx_mmio_data_xfer(struct ata_queued_cmd *qc,
40				unsigned char *buf, unsigned int buflen, int rw)
41{
42	unsigned int i;
43	unsigned int words = buflen >> 1;
44	u16 *buf16 = (u16 *) buf;
45	struct ata_port *ap = qc->dev->link->ap;
46	void __iomem *mmio = ap->ioaddr.data_addr;
47	struct ixp4xx_pata_data *data = dev_get_platdata(ap->host->dev);
48
49	/* set the expansion bus in 16bit mode and restore
50	 * 8 bit mode after the transaction.
51	 */
52	*data->cs0_cfg &= ~(0x01);
53	udelay(100);
54
55	/* Transfer multiple of 2 bytes */
56	if (rw == READ)
57		for (i = 0; i < words; i++)
58			buf16[i] = readw(mmio);
59	else
60		for (i = 0; i < words; i++)
61			writew(buf16[i], mmio);
62
63	/* Transfer trailing 1 byte, if any. */
64	if (unlikely(buflen & 0x01)) {
65		u16 align_buf[1] = { 0 };
66		unsigned char *trailing_buf = buf + buflen - 1;
67
68		if (rw == READ) {
69			align_buf[0] = readw(mmio);
70			memcpy(trailing_buf, align_buf, 1);
71		} else {
72			memcpy(align_buf, trailing_buf, 1);
73			writew(align_buf[0], mmio);
74		}
75		words++;
76	}
77
78	udelay(100);
79	*data->cs0_cfg |= 0x01;
80
81	return words << 1;
82}
83
84static struct scsi_host_template ixp4xx_sht = {
85	ATA_PIO_SHT(DRV_NAME),
86};
87
88static struct ata_port_operations ixp4xx_port_ops = {
89	.inherits		= &ata_sff_port_ops,
90	.sff_data_xfer		= ixp4xx_mmio_data_xfer,
91	.cable_detect		= ata_cable_40wire,
92	.set_mode		= ixp4xx_set_mode,
93};
94
95static void ixp4xx_setup_port(struct ata_port *ap,
96			      struct ixp4xx_pata_data *data,
97			      unsigned long raw_cs0, unsigned long raw_cs1)
98{
99	struct ata_ioports *ioaddr = &ap->ioaddr;
100	unsigned long raw_cmd = raw_cs0;
101	unsigned long raw_ctl = raw_cs1 + 0x06;
102
103	ioaddr->cmd_addr	= data->cs0;
104	ioaddr->altstatus_addr	= data->cs1 + 0x06;
105	ioaddr->ctl_addr	= data->cs1 + 0x06;
106
107	ata_sff_std_ports(ioaddr);
108
109#ifndef __ARMEB__
110
111	/* adjust the addresses to handle the address swizzling of the
112	 * ixp4xx in little endian mode.
113	 */
114
115	*(unsigned long *)&ioaddr->data_addr		^= 0x02;
116	*(unsigned long *)&ioaddr->cmd_addr		^= 0x03;
117	*(unsigned long *)&ioaddr->altstatus_addr	^= 0x03;
118	*(unsigned long *)&ioaddr->ctl_addr		^= 0x03;
119	*(unsigned long *)&ioaddr->error_addr		^= 0x03;
120	*(unsigned long *)&ioaddr->feature_addr		^= 0x03;
121	*(unsigned long *)&ioaddr->nsect_addr		^= 0x03;
122	*(unsigned long *)&ioaddr->lbal_addr		^= 0x03;
123	*(unsigned long *)&ioaddr->lbam_addr		^= 0x03;
124	*(unsigned long *)&ioaddr->lbah_addr		^= 0x03;
125	*(unsigned long *)&ioaddr->device_addr		^= 0x03;
126	*(unsigned long *)&ioaddr->status_addr		^= 0x03;
127	*(unsigned long *)&ioaddr->command_addr		^= 0x03;
128
129	raw_cmd ^= 0x03;
130	raw_ctl ^= 0x03;
131#endif
132
133	ata_port_desc(ap, "cmd 0x%lx ctl 0x%lx", raw_cmd, raw_ctl);
134}
135
136static int ixp4xx_pata_probe(struct platform_device *pdev)
137{
138	struct resource *cs0, *cs1;
139	struct ata_host *host;
140	struct ata_port *ap;
141	struct ixp4xx_pata_data *data = dev_get_platdata(&pdev->dev);
142	int ret;
143	int irq;
144
145	cs0 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
146	cs1 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
147
148	if (!cs0 || !cs1)
149		return -EINVAL;
150
151	/* allocate host */
152	host = ata_host_alloc(&pdev->dev, 1);
153	if (!host)
154		return -ENOMEM;
155
156	/* acquire resources and fill host */
157	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
158	if (ret)
159		return ret;
160
161	data->cs0 = devm_ioremap(&pdev->dev, cs0->start, 0x1000);
162	data->cs1 = devm_ioremap(&pdev->dev, cs1->start, 0x1000);
163
164	if (!data->cs0 || !data->cs1)
165		return -ENOMEM;
166
167	irq = platform_get_irq(pdev, 0);
168	if (irq > 0)
169		irq_set_irq_type(irq, IRQ_TYPE_EDGE_RISING);
170	else if (irq < 0)
171		return irq;
172	else
173		return -EINVAL;
174
175	/* Setup expansion bus chip selects */
176	*data->cs0_cfg = data->cs0_bits;
177	*data->cs1_cfg = data->cs1_bits;
178
179	ap = host->ports[0];
180
181	ap->ops	= &ixp4xx_port_ops;
182	ap->pio_mask = ATA_PIO4;
183	ap->flags |= ATA_FLAG_NO_ATAPI;
184
185	ixp4xx_setup_port(ap, data, cs0->start, cs1->start);
186
187	ata_print_version_once(&pdev->dev, DRV_VERSION);
188
189	/* activate host */
190	return ata_host_activate(host, irq, ata_sff_interrupt, 0, &ixp4xx_sht);
191}
192
193static struct platform_driver ixp4xx_pata_platform_driver = {
194	.driver	 = {
195		.name   = DRV_NAME,
196	},
197	.probe		= ixp4xx_pata_probe,
198	.remove		= ata_platform_remove_one,
199};
200
201module_platform_driver(ixp4xx_pata_platform_driver);
202
203MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
204MODULE_DESCRIPTION("low-level driver for ixp4xx Compact Flash PATA");
205MODULE_LICENSE("GPL");
206MODULE_VERSION(DRV_VERSION);
207MODULE_ALIAS("platform:" DRV_NAME);
208