xref: /openbmc/linux/drivers/ata/pata_falcon.c (revision 046b212a)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 /*
4  * Atari Falcon PATA controller driver
5  *
6  * Copyright (c) 2016 Samsung Electronics Co., Ltd.
7  *		http://www.samsung.com
8  *
9  * Based on falconide.c:
10  *
11  *     Created 12 Jul 1997 by Geert Uytterhoeven
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/blkdev.h>
18 #include <linux/delay.h>
19 #include <scsi/scsi_host.h>
20 #include <scsi/scsi_cmnd.h>
21 #include <linux/ata.h>
22 #include <linux/libata.h>
23 #include <linux/mm.h>
24 #include <linux/interrupt.h>
25 #include <linux/platform_device.h>
26 
27 #include <asm/setup.h>
28 #include <asm/atarihw.h>
29 #include <asm/atariints.h>
30 #include <asm/atari_stdma.h>
31 
32 #define DRV_NAME "pata_falcon"
33 #define DRV_VERSION "0.1.0"
34 
35 static int pata_falcon_swap_mask;
36 
37 module_param_named(data_swab, pata_falcon_swap_mask, int, 0444);
38 MODULE_PARM_DESC(data_swab, "Data byte swap enable/disable bitmap (0x1==drive1, 0x2==drive2, 0x4==drive3, 0x8==drive4, default==0)");
39 
40 static const struct scsi_host_template pata_falcon_sht = {
41 	ATA_PIO_SHT(DRV_NAME),
42 };
43 
44 static unsigned int pata_falcon_data_xfer(struct ata_queued_cmd *qc,
45 					  unsigned char *buf,
46 					  unsigned int buflen, int rw)
47 {
48 	struct ata_device *dev = qc->dev;
49 	struct ata_port *ap = dev->link->ap;
50 	void __iomem *data_addr = ap->ioaddr.data_addr;
51 	unsigned int words = buflen >> 1;
52 	struct scsi_cmnd *cmd = qc->scsicmd;
53 	bool swap = 1;
54 
55 	if (dev->class == ATA_DEV_ATA && cmd &&
56 	    !blk_rq_is_passthrough(scsi_cmd_to_rq(cmd)))
57 		swap = (uintptr_t)ap->private_data & BIT(dev->devno);
58 
59 	/* Transfer multiple of 2 bytes */
60 	if (rw == READ) {
61 		if (swap)
62 			raw_insw_swapw(data_addr, (u16 *)buf, words);
63 		else
64 			raw_insw(data_addr, (u16 *)buf, words);
65 	} else {
66 		if (swap)
67 			raw_outsw_swapw(data_addr, (u16 *)buf, words);
68 		else
69 			raw_outsw(data_addr, (u16 *)buf, words);
70 	}
71 
72 	/* Transfer trailing byte, if any. */
73 	if (unlikely(buflen & 0x01)) {
74 		unsigned char pad[2] = { };
75 
76 		/* Point buf to the tail of buffer */
77 		buf += buflen - 1;
78 
79 		if (rw == READ) {
80 			if (swap)
81 				raw_insw_swapw(data_addr, (u16 *)pad, 1);
82 			else
83 				raw_insw(data_addr, (u16 *)pad, 1);
84 			*buf = pad[0];
85 		} else {
86 			pad[0] = *buf;
87 			if (swap)
88 				raw_outsw_swapw(data_addr, (u16 *)pad, 1);
89 			else
90 				raw_outsw(data_addr, (u16 *)pad, 1);
91 		}
92 		words++;
93 	}
94 
95 	return words << 1;
96 }
97 
98 /*
99  * Provide our own set_mode() as we don't want to change anything that has
100  * already been configured..
101  */
102 static int pata_falcon_set_mode(struct ata_link *link,
103 				struct ata_device **unused)
104 {
105 	struct ata_device *dev;
106 
107 	ata_for_each_dev(dev, link, ENABLED) {
108 		/* We don't really care */
109 		dev->pio_mode = dev->xfer_mode = XFER_PIO_0;
110 		dev->xfer_shift = ATA_SHIFT_PIO;
111 		dev->flags |= ATA_DFLAG_PIO;
112 		ata_dev_info(dev, "configured for PIO\n");
113 	}
114 	return 0;
115 }
116 
117 static struct ata_port_operations pata_falcon_ops = {
118 	.inherits	= &ata_sff_port_ops,
119 	.sff_data_xfer	= pata_falcon_data_xfer,
120 	.cable_detect	= ata_cable_unknown,
121 	.set_mode	= pata_falcon_set_mode,
122 };
123 
124 static int __init pata_falcon_init_one(struct platform_device *pdev)
125 {
126 	struct resource *base_mem_res, *ctl_mem_res;
127 	struct resource *base_res, *ctl_res, *irq_res;
128 	struct ata_host *host;
129 	struct ata_port *ap;
130 	void __iomem *base, *ctl_base;
131 	int mask_shift = 0; /* Q40 & Falcon default */
132 	int irq = 0, io_offset = 1, reg_shift = 2; /* Falcon defaults */
133 
134 	dev_info(&pdev->dev, "Atari Falcon and Q40/Q60 PATA controller\n");
135 
136 	base_res = platform_get_resource(pdev, IORESOURCE_IO, 0);
137 	if (base_res && !devm_request_region(&pdev->dev, base_res->start,
138 					   resource_size(base_res), DRV_NAME)) {
139 		dev_err(&pdev->dev, "resources busy\n");
140 		return -EBUSY;
141 	}
142 
143 	ctl_res = platform_get_resource(pdev, IORESOURCE_IO, 1);
144 	if (ctl_res && !devm_request_region(&pdev->dev, ctl_res->start,
145 					    resource_size(ctl_res), DRV_NAME)) {
146 		dev_err(&pdev->dev, "resources busy\n");
147 		return -EBUSY;
148 	}
149 
150 	base_mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
151 	if (!base_mem_res)
152 		return -ENODEV;
153 	if (!devm_request_mem_region(&pdev->dev, base_mem_res->start,
154 				     resource_size(base_mem_res), DRV_NAME)) {
155 		dev_err(&pdev->dev, "resources busy\n");
156 		return -EBUSY;
157 	}
158 
159 	ctl_mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
160 	if (!ctl_mem_res)
161 		return -ENODEV;
162 
163 	/* allocate host */
164 	host = ata_host_alloc(&pdev->dev, 1);
165 	if (!host)
166 		return -ENOMEM;
167 	ap = host->ports[0];
168 
169 	ap->ops = &pata_falcon_ops;
170 	ap->pio_mask = ATA_PIO4;
171 	ap->flags |= ATA_FLAG_SLAVE_POSS | ATA_FLAG_NO_IORDY;
172 
173 	/* N.B. this assumes data_addr will be used for word-sized I/O only */
174 	ap->ioaddr.data_addr = (void __iomem *)base_mem_res->start;
175 
176 	if (base_res) {		/* only Q40 has IO resources */
177 		io_offset = 0x10000;
178 		reg_shift = 0;
179 		base = (void __iomem *)base_res->start;
180 		ctl_base = (void __iomem *)ctl_res->start;
181 	} else {
182 		base = (void __iomem *)base_mem_res->start;
183 		ctl_base = (void __iomem *)ctl_mem_res->start;
184 	}
185 
186 	ap->ioaddr.error_addr	= base + io_offset + (1 << reg_shift);
187 	ap->ioaddr.feature_addr	= base + io_offset + (1 << reg_shift);
188 	ap->ioaddr.nsect_addr	= base + io_offset + (2 << reg_shift);
189 	ap->ioaddr.lbal_addr	= base + io_offset + (3 << reg_shift);
190 	ap->ioaddr.lbam_addr	= base + io_offset + (4 << reg_shift);
191 	ap->ioaddr.lbah_addr	= base + io_offset + (5 << reg_shift);
192 	ap->ioaddr.device_addr	= base + io_offset + (6 << reg_shift);
193 	ap->ioaddr.status_addr	= base + io_offset + (7 << reg_shift);
194 	ap->ioaddr.command_addr	= base + io_offset + (7 << reg_shift);
195 
196 	ap->ioaddr.altstatus_addr	= ctl_base + io_offset;
197 	ap->ioaddr.ctl_addr		= ctl_base + io_offset;
198 
199 	ata_port_desc(ap, "cmd %px ctl %px data %px",
200 		      base, ctl_base, ap->ioaddr.data_addr);
201 
202 	if (pdev->id > 0)
203 		mask_shift = 2;
204 	ap->private_data = (void *)(uintptr_t)(pata_falcon_swap_mask >> mask_shift);
205 
206 	irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
207 	if (irq_res && irq_res->start > 0) {
208 		irq = irq_res->start;
209 	} else {
210 		ap->flags |= ATA_FLAG_PIO_POLLING;
211 		ata_port_desc(ap, "no IRQ, using PIO polling");
212 	}
213 
214 	/* activate */
215 	return ata_host_activate(host, irq, irq ? ata_sff_interrupt : NULL,
216 				 IRQF_SHARED, &pata_falcon_sht);
217 }
218 
219 static int __exit pata_falcon_remove_one(struct platform_device *pdev)
220 {
221 	struct ata_host *host = platform_get_drvdata(pdev);
222 
223 	ata_host_detach(host);
224 
225 	return 0;
226 }
227 
228 static struct platform_driver pata_falcon_driver = {
229 	.remove = __exit_p(pata_falcon_remove_one),
230 	.driver   = {
231 		.name	= "atari-falcon-ide",
232 	},
233 };
234 
235 module_platform_driver_probe(pata_falcon_driver, pata_falcon_init_one);
236 
237 MODULE_AUTHOR("Bartlomiej Zolnierkiewicz");
238 MODULE_DESCRIPTION("low-level driver for Atari Falcon PATA");
239 MODULE_LICENSE("GPL v2");
240 MODULE_ALIAS("platform:atari-falcon-ide");
241 MODULE_VERSION(DRV_VERSION);
242