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#include <asm/ide.h>
 32
 33#define DRV_NAME "pata_falcon"
 34#define DRV_VERSION "0.1.0"
 35
 36#define ATA_HD_BASE	0xfff00000
 37#define ATA_HD_CONTROL	0x39
 38
 39static struct scsi_host_template pata_falcon_sht = {
 40	ATA_PIO_SHT(DRV_NAME),
 41};
 42
 43static unsigned int pata_falcon_data_xfer(struct ata_queued_cmd *qc,
 44					  unsigned char *buf,
 45					  unsigned int buflen, int rw)
 46{
 47	struct ata_device *dev = qc->dev;
 48	struct ata_port *ap = dev->link->ap;
 49	void __iomem *data_addr = ap->ioaddr.data_addr;
 50	unsigned int words = buflen >> 1;
 51	struct scsi_cmnd *cmd = qc->scsicmd;
 52	bool swap = 1;
 53
 54	if (dev->class == ATA_DEV_ATA && cmd && cmd->request &&
 55	    !blk_rq_is_passthrough(cmd->request))
 56		swap = 0;
 57
 58	/* Transfer multiple of 2 bytes */
 59	if (rw == READ) {
 60		if (swap)
 61			raw_insw_swapw((u16 *)data_addr, (u16 *)buf, words);
 62		else
 63			raw_insw((u16 *)data_addr, (u16 *)buf, words);
 64	} else {
 65		if (swap)
 66			raw_outsw_swapw((u16 *)data_addr, (u16 *)buf, words);
 67		else
 68			raw_outsw((u16 *)data_addr, (u16 *)buf, words);
 69	}
 70
 71	/* Transfer trailing byte, if any. */
 72	if (unlikely(buflen & 0x01)) {
 73		unsigned char pad[2] = { };
 74
 75		/* Point buf to the tail of buffer */
 76		buf += buflen - 1;
 77
 78		if (rw == READ) {
 79			if (swap)
 80				raw_insw_swapw((u16 *)data_addr, (u16 *)pad, 1);
 81			else
 82				raw_insw((u16 *)data_addr, (u16 *)pad, 1);
 83			*buf = pad[0];
 84		} else {
 85			pad[0] = *buf;
 86			if (swap)
 87				raw_outsw_swapw((u16 *)data_addr, (u16 *)pad, 1);
 88			else
 89				raw_outsw((u16 *)data_addr, (u16 *)pad, 1);
 90		}
 91		words++;
 92	}
 93
 94	return words << 1;
 95}
 96
 97/*
 98 * Provide our own set_mode() as we don't want to change anything that has
 99 * already been configured..
100 */
101static int pata_falcon_set_mode(struct ata_link *link,
102				struct ata_device **unused)
103{
104	struct ata_device *dev;
105
106	ata_for_each_dev(dev, link, ENABLED) {
107		/* We don't really care */
108		dev->pio_mode = dev->xfer_mode = XFER_PIO_0;
109		dev->xfer_shift = ATA_SHIFT_PIO;
110		dev->flags |= ATA_DFLAG_PIO;
111		ata_dev_info(dev, "configured for PIO\n");
112	}
113	return 0;
114}
115
116static struct ata_port_operations pata_falcon_ops = {
117	.inherits	= &ata_sff_port_ops,
118	.sff_data_xfer	= pata_falcon_data_xfer,
119	.cable_detect	= ata_cable_unknown,
120	.set_mode	= pata_falcon_set_mode,
121};
122
123static int pata_falcon_init_one(void)
124{
125	struct ata_host *host;
126	struct ata_port *ap;
127	struct platform_device *pdev;
128	void __iomem *base;
129
130	if (!MACH_IS_ATARI || !ATARIHW_PRESENT(IDE))
131		return -ENODEV;
132
133	pr_info(DRV_NAME ": Atari Falcon PATA controller\n");
134
135	pdev = platform_device_register_simple(DRV_NAME, 0, NULL, 0);
136	if (IS_ERR(pdev))
137		return PTR_ERR(pdev);
138
139	if (!devm_request_mem_region(&pdev->dev, ATA_HD_BASE, 0x40, DRV_NAME)) {
140		pr_err(DRV_NAME ": resources busy\n");
141		return -EBUSY;
142	}
143
144	/* allocate host */
145	host = ata_host_alloc(&pdev->dev, 1);
146	if (!host)
147		return -ENOMEM;
148	ap = host->ports[0];
149
150	ap->ops = &pata_falcon_ops;
151	ap->pio_mask = ATA_PIO4;
152	ap->flags |= ATA_FLAG_SLAVE_POSS | ATA_FLAG_NO_IORDY;
153	ap->flags |= ATA_FLAG_PIO_POLLING;
154
155	base = (void __iomem *)ATA_HD_BASE;
156	ap->ioaddr.data_addr		= base;
157	ap->ioaddr.error_addr		= base + 1 + 1 * 4;
158	ap->ioaddr.feature_addr		= base + 1 + 1 * 4;
159	ap->ioaddr.nsect_addr		= base + 1 + 2 * 4;
160	ap->ioaddr.lbal_addr		= base + 1 + 3 * 4;
161	ap->ioaddr.lbam_addr		= base + 1 + 4 * 4;
162	ap->ioaddr.lbah_addr		= base + 1 + 5 * 4;
163	ap->ioaddr.device_addr		= base + 1 + 6 * 4;
164	ap->ioaddr.status_addr		= base + 1 + 7 * 4;
165	ap->ioaddr.command_addr		= base + 1 + 7 * 4;
166
167	ap->ioaddr.altstatus_addr	= base + ATA_HD_CONTROL;
168	ap->ioaddr.ctl_addr		= base + ATA_HD_CONTROL;
169
170	ata_port_desc(ap, "cmd 0x%lx ctl 0x%lx", (unsigned long)base,
171		      (unsigned long)base + ATA_HD_CONTROL);
172
173	/* activate */
174	return ata_host_activate(host, 0, NULL, 0, &pata_falcon_sht);
175}
176
177module_init(pata_falcon_init_one);
178
179MODULE_AUTHOR("Bartlomiej Zolnierkiewicz");
180MODULE_DESCRIPTION("low-level driver for Atari Falcon PATA");
181MODULE_LICENSE("GPL v2");
182MODULE_VERSION(DRV_VERSION);