1/*
2 * Copyright (C) 2006-2007 PA Semi, Inc
3 *
4 * Author: Egor Martovetsky <egor@pasemi.com>
5 * Maintained by: Olof Johansson <olof@lixom.net>
6 *
7 * Driver for the PWRficient onchip NAND flash interface
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
21 */
22
23#undef DEBUG
24
25#include <linux/slab.h>
26#include <linux/module.h>
27#include <linux/mtd/mtd.h>
28#include <linux/mtd/nand.h>
29#include <linux/mtd/nand_ecc.h>
30#include <linux/of_address.h>
31#include <linux/of_irq.h>
32#include <linux/of_platform.h>
33#include <linux/platform_device.h>
34#include <linux/pci.h>
35
36#include <asm/io.h>
37
38#define LBICTRL_LPCCTL_NR		0x00004000
39#define CLE_PIN_CTL			15
40#define ALE_PIN_CTL			14
41
42static unsigned int lpcctl;
43static struct mtd_info *pasemi_nand_mtd;
44static const char driver_name[] = "pasemi-nand";
45
46static void pasemi_read_buf(struct mtd_info *mtd, u_char *buf, int len)
47{
48	struct nand_chip *chip = mtd->priv;
49
50	while (len > 0x800) {
51		memcpy_fromio(buf, chip->IO_ADDR_R, 0x800);
52		buf += 0x800;
53		len -= 0x800;
54	}
55	memcpy_fromio(buf, chip->IO_ADDR_R, len);
56}
57
58static void pasemi_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
59{
60	struct nand_chip *chip = mtd->priv;
61
62	while (len > 0x800) {
63		memcpy_toio(chip->IO_ADDR_R, buf, 0x800);
64		buf += 0x800;
65		len -= 0x800;
66	}
67	memcpy_toio(chip->IO_ADDR_R, buf, len);
68}
69
70static void pasemi_hwcontrol(struct mtd_info *mtd, int cmd,
71			     unsigned int ctrl)
72{
73	struct nand_chip *chip = mtd->priv;
74
75	if (cmd == NAND_CMD_NONE)
76		return;
77
78	if (ctrl & NAND_CLE)
79		out_8(chip->IO_ADDR_W + (1 << CLE_PIN_CTL), cmd);
80	else
81		out_8(chip->IO_ADDR_W + (1 << ALE_PIN_CTL), cmd);
82
83	/* Push out posted writes */
84	eieio();
85	inl(lpcctl);
86}
87
88int pasemi_device_ready(struct mtd_info *mtd)
89{
90	return !!(inl(lpcctl) & LBICTRL_LPCCTL_NR);
91}
92
93static int pasemi_nand_probe(struct platform_device *ofdev)
94{
95	struct pci_dev *pdev;
96	struct device_node *np = ofdev->dev.of_node;
97	struct resource res;
98	struct nand_chip *chip;
99	int err = 0;
100
101	err = of_address_to_resource(np, 0, &res);
102
103	if (err)
104		return -EINVAL;
105
106	/* We only support one device at the moment */
107	if (pasemi_nand_mtd)
108		return -ENODEV;
109
110	pr_debug("pasemi_nand at %pR\n", &res);
111
112	/* Allocate memory for MTD device structure and private data */
113	pasemi_nand_mtd = kzalloc(sizeof(struct mtd_info) +
114				  sizeof(struct nand_chip), GFP_KERNEL);
115	if (!pasemi_nand_mtd) {
116		printk(KERN_WARNING
117		       "Unable to allocate PASEMI NAND MTD device structure\n");
118		err = -ENOMEM;
119		goto out;
120	}
121
122	/* Get pointer to private data */
123	chip = (struct nand_chip *)&pasemi_nand_mtd[1];
124
125	/* Link the private data with the MTD structure */
126	pasemi_nand_mtd->priv = chip;
127	pasemi_nand_mtd->owner = THIS_MODULE;
128
129	chip->IO_ADDR_R = of_iomap(np, 0);
130	chip->IO_ADDR_W = chip->IO_ADDR_R;
131
132	if (!chip->IO_ADDR_R) {
133		err = -EIO;
134		goto out_mtd;
135	}
136
137	pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa008, NULL);
138	if (!pdev) {
139		err = -ENODEV;
140		goto out_ior;
141	}
142
143	lpcctl = pci_resource_start(pdev, 0);
144	pci_dev_put(pdev);
145
146	if (!request_region(lpcctl, 4, driver_name)) {
147		err = -EBUSY;
148		goto out_ior;
149	}
150
151	chip->cmd_ctrl = pasemi_hwcontrol;
152	chip->dev_ready = pasemi_device_ready;
153	chip->read_buf = pasemi_read_buf;
154	chip->write_buf = pasemi_write_buf;
155	chip->chip_delay = 0;
156	chip->ecc.mode = NAND_ECC_SOFT;
157
158	/* Enable the following for a flash based bad block table */
159	chip->bbt_options = NAND_BBT_USE_FLASH;
160
161	/* Scan to find existence of the device */
162	if (nand_scan(pasemi_nand_mtd, 1)) {
163		err = -ENXIO;
164		goto out_lpc;
165	}
166
167	if (mtd_device_register(pasemi_nand_mtd, NULL, 0)) {
168		printk(KERN_ERR "pasemi_nand: Unable to register MTD device\n");
169		err = -ENODEV;
170		goto out_lpc;
171	}
172
173	printk(KERN_INFO "PA Semi NAND flash at %08llx, control at I/O %x\n",
174	       res.start, lpcctl);
175
176	return 0;
177
178 out_lpc:
179	release_region(lpcctl, 4);
180 out_ior:
181	iounmap(chip->IO_ADDR_R);
182 out_mtd:
183	kfree(pasemi_nand_mtd);
184 out:
185	return err;
186}
187
188static int pasemi_nand_remove(struct platform_device *ofdev)
189{
190	struct nand_chip *chip;
191
192	if (!pasemi_nand_mtd)
193		return 0;
194
195	chip = pasemi_nand_mtd->priv;
196
197	/* Release resources, unregister device */
198	nand_release(pasemi_nand_mtd);
199
200	release_region(lpcctl, 4);
201
202	iounmap(chip->IO_ADDR_R);
203
204	/* Free the MTD device structure */
205	kfree(pasemi_nand_mtd);
206
207	pasemi_nand_mtd = NULL;
208
209	return 0;
210}
211
212static const struct of_device_id pasemi_nand_match[] =
213{
214	{
215		.compatible   = "pasemi,localbus-nand",
216	},
217	{},
218};
219
220MODULE_DEVICE_TABLE(of, pasemi_nand_match);
221
222static struct platform_driver pasemi_nand_driver =
223{
224	.driver = {
225		.name = driver_name,
226		.of_match_table = pasemi_nand_match,
227	},
228	.probe		= pasemi_nand_probe,
229	.remove		= pasemi_nand_remove,
230};
231
232module_platform_driver(pasemi_nand_driver);
233
234MODULE_LICENSE("GPL");
235MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>");
236MODULE_DESCRIPTION("NAND flash interface driver for PA Semi PWRficient");
237