1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *  Copyright (C) 2004 Richard Purdie
4 *  Copyright (C) 2008 Dmitry Baryshkov
5 *
6 *  Based on Sharp's NAND driver sharp_sl.c
7 */
8
9#include <linux/slab.h>
10#include <linux/module.h>
11#include <linux/delay.h>
12#include <linux/mtd/mtd.h>
13#include <linux/mtd/rawnand.h>
14#include <linux/mtd/partitions.h>
15#include <linux/mtd/sharpsl.h>
16#include <linux/interrupt.h>
17#include <linux/platform_device.h>
18#include <linux/io.h>
19
20struct sharpsl_nand {
21	struct nand_controller	controller;
22	struct nand_chip	chip;
23
24	void __iomem		*io;
25};
26
27static inline struct sharpsl_nand *mtd_to_sharpsl(struct mtd_info *mtd)
28{
29	return container_of(mtd_to_nand(mtd), struct sharpsl_nand, chip);
30}
31
32/* register offset */
33#define ECCLPLB		0x00	/* line parity 7 - 0 bit */
34#define ECCLPUB		0x04	/* line parity 15 - 8 bit */
35#define ECCCP		0x08	/* column parity 5 - 0 bit */
36#define ECCCNTR		0x0C	/* ECC byte counter */
37#define ECCCLRR		0x10	/* cleare ECC */
38#define FLASHIO		0x14	/* Flash I/O */
39#define FLASHCTL	0x18	/* Flash Control */
40
41/* Flash control bit */
42#define FLRYBY		(1 << 5)
43#define FLCE1		(1 << 4)
44#define FLWP		(1 << 3)
45#define FLALE		(1 << 2)
46#define FLCLE		(1 << 1)
47#define FLCE0		(1 << 0)
48
49/*
50 *	hardware specific access to control-lines
51 *	ctrl:
52 *	NAND_CNE: bit 0 -> ! bit 0 & 4
53 *	NAND_CLE: bit 1 -> bit 1
54 *	NAND_ALE: bit 2 -> bit 2
55 *
56 */
57static void sharpsl_nand_hwcontrol(struct nand_chip *chip, int cmd,
58				   unsigned int ctrl)
59{
60	struct sharpsl_nand *sharpsl = mtd_to_sharpsl(nand_to_mtd(chip));
61
62	if (ctrl & NAND_CTRL_CHANGE) {
63		unsigned char bits = ctrl & 0x07;
64
65		bits |= (ctrl & 0x01) << 4;
66
67		bits ^= 0x11;
68
69		writeb((readb(sharpsl->io + FLASHCTL) & ~0x17) | bits, sharpsl->io + FLASHCTL);
70	}
71
72	if (cmd != NAND_CMD_NONE)
73		writeb(cmd, chip->legacy.IO_ADDR_W);
74}
75
76static int sharpsl_nand_dev_ready(struct nand_chip *chip)
77{
78	struct sharpsl_nand *sharpsl = mtd_to_sharpsl(nand_to_mtd(chip));
79	return !((readb(sharpsl->io + FLASHCTL) & FLRYBY) == 0);
80}
81
82static void sharpsl_nand_enable_hwecc(struct nand_chip *chip, int mode)
83{
84	struct sharpsl_nand *sharpsl = mtd_to_sharpsl(nand_to_mtd(chip));
85	writeb(0, sharpsl->io + ECCCLRR);
86}
87
88static int sharpsl_nand_calculate_ecc(struct nand_chip *chip,
89				      const u_char * dat, u_char * ecc_code)
90{
91	struct sharpsl_nand *sharpsl = mtd_to_sharpsl(nand_to_mtd(chip));
92	ecc_code[0] = ~readb(sharpsl->io + ECCLPUB);
93	ecc_code[1] = ~readb(sharpsl->io + ECCLPLB);
94	ecc_code[2] = (~readb(sharpsl->io + ECCCP) << 2) | 0x03;
95	return readb(sharpsl->io + ECCCNTR) != 0;
96}
97
98static int sharpsl_attach_chip(struct nand_chip *chip)
99{
100	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
101		return 0;
102
103	chip->ecc.size = 256;
104	chip->ecc.bytes = 3;
105	chip->ecc.strength = 1;
106	chip->ecc.hwctl = sharpsl_nand_enable_hwecc;
107	chip->ecc.calculate = sharpsl_nand_calculate_ecc;
108	chip->ecc.correct = rawnand_sw_hamming_correct;
109
110	return 0;
111}
112
113static const struct nand_controller_ops sharpsl_ops = {
114	.attach_chip = sharpsl_attach_chip,
115};
116
117/*
118 * Main initialization routine
119 */
120static int sharpsl_nand_probe(struct platform_device *pdev)
121{
122	struct nand_chip *this;
123	struct mtd_info *mtd;
124	struct resource *r;
125	int err = 0;
126	struct sharpsl_nand *sharpsl;
127	struct sharpsl_nand_platform_data *data = dev_get_platdata(&pdev->dev);
128
129	if (!data) {
130		dev_err(&pdev->dev, "no platform data!\n");
131		return -EINVAL;
132	}
133
134	/* Allocate memory for MTD device structure and private data */
135	sharpsl = kzalloc(sizeof(struct sharpsl_nand), GFP_KERNEL);
136	if (!sharpsl)
137		return -ENOMEM;
138
139	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
140	if (!r) {
141		dev_err(&pdev->dev, "no io memory resource defined!\n");
142		err = -ENODEV;
143		goto err_get_res;
144	}
145
146	/* map physical address */
147	sharpsl->io = ioremap(r->start, resource_size(r));
148	if (!sharpsl->io) {
149		dev_err(&pdev->dev, "ioremap to access Sharp SL NAND chip failed\n");
150		err = -EIO;
151		goto err_ioremap;
152	}
153
154	/* Get pointer to private data */
155	this = (struct nand_chip *)(&sharpsl->chip);
156
157	nand_controller_init(&sharpsl->controller);
158	sharpsl->controller.ops = &sharpsl_ops;
159	this->controller = &sharpsl->controller;
160
161	/* Link the private data with the MTD structure */
162	mtd = nand_to_mtd(this);
163	mtd->dev.parent = &pdev->dev;
164	mtd_set_ooblayout(mtd, data->ecc_layout);
165
166	platform_set_drvdata(pdev, sharpsl);
167
168	/*
169	 * PXA initialize
170	 */
171	writeb(readb(sharpsl->io + FLASHCTL) | FLWP, sharpsl->io + FLASHCTL);
172
173	/* Set address of NAND IO lines */
174	this->legacy.IO_ADDR_R = sharpsl->io + FLASHIO;
175	this->legacy.IO_ADDR_W = sharpsl->io + FLASHIO;
176	/* Set address of hardware control function */
177	this->legacy.cmd_ctrl = sharpsl_nand_hwcontrol;
178	this->legacy.dev_ready = sharpsl_nand_dev_ready;
179	/* 15 us command delay time */
180	this->legacy.chip_delay = 15;
181	this->badblock_pattern = data->badblock_pattern;
182
183	/* Scan to find existence of the device */
184	err = nand_scan(this, 1);
185	if (err)
186		goto err_scan;
187
188	/* Register the partitions */
189	mtd->name = "sharpsl-nand";
190
191	err = mtd_device_parse_register(mtd, data->part_parsers, NULL,
192					data->partitions, data->nr_partitions);
193	if (err)
194		goto err_add;
195
196	/* Return happy */
197	return 0;
198
199err_add:
200	nand_cleanup(this);
201
202err_scan:
203	iounmap(sharpsl->io);
204err_ioremap:
205err_get_res:
206	kfree(sharpsl);
207	return err;
208}
209
210/*
211 * Clean up routine
212 */
213static void sharpsl_nand_remove(struct platform_device *pdev)
214{
215	struct sharpsl_nand *sharpsl = platform_get_drvdata(pdev);
216	struct nand_chip *chip = &sharpsl->chip;
217	int ret;
218
219	/* Unregister device */
220	ret = mtd_device_unregister(nand_to_mtd(chip));
221	WARN_ON(ret);
222
223	/* Release resources */
224	nand_cleanup(chip);
225
226	iounmap(sharpsl->io);
227
228	/* Free the driver's structure */
229	kfree(sharpsl);
230}
231
232static struct platform_driver sharpsl_nand_driver = {
233	.driver = {
234		.name	= "sharpsl-nand",
235	},
236	.probe		= sharpsl_nand_probe,
237	.remove_new	= sharpsl_nand_remove,
238};
239
240module_platform_driver(sharpsl_nand_driver);
241
242MODULE_LICENSE("GPL");
243MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
244MODULE_DESCRIPTION("Device specific logic for NAND flash on Sharp SL-C7xx Series");
245