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
 35static int pata_falcon_swap_mask;
 36
 37module_param_named(data_swab, pata_falcon_swap_mask, int, 0444);
 38MODULE_PARM_DESC(data_swab, "Data byte swap enable/disable bitmap (0x1==drive1, 0x2==drive2, 0x4==drive3, 0x8==drive4, default==0)");
 39
 40static const struct scsi_host_template pata_falcon_sht = {
 41	ATA_PIO_SHT(DRV_NAME),
 42};
 43
 44static 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 */
102static 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
117static 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
124static int 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
219static void 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
226static struct platform_driver pata_falcon_driver = {
227	.probe = pata_falcon_init_one,
228	.remove = pata_falcon_remove_one,
229	.driver = {
230		.name	= "atari-falcon-ide",
231	},
232};
233
234module_platform_driver(pata_falcon_driver);
235
236MODULE_AUTHOR("Bartlomiej Zolnierkiewicz");
237MODULE_DESCRIPTION("low-level driver for Atari Falcon PATA");
238MODULE_LICENSE("GPL v2");
239MODULE_ALIAS("platform:atari-falcon-ide");
240MODULE_VERSION(DRV_VERSION);