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_to_nand(mtd);
 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_to_nand(mtd);
 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_to_nand(mtd);
 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 device *dev = &ofdev->dev;
 96	struct pci_dev *pdev;
 97	struct device_node *np = dev->of_node;
 98	struct resource res;
 99	struct nand_chip *chip;
100	int err = 0;
101
102	err = of_address_to_resource(np, 0, &res);
103
104	if (err)
105		return -EINVAL;
106
107	/* We only support one device at the moment */
108	if (pasemi_nand_mtd)
109		return -ENODEV;
110
111	dev_dbg(dev, "pasemi_nand at %pR\n", &res);
112
113	/* Allocate memory for MTD device structure and private data */
114	chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
115	if (!chip) {
116		err = -ENOMEM;
117		goto out;
118	}
119
120	pasemi_nand_mtd = nand_to_mtd(chip);
121
122	/* Link the private data with the MTD structure */
123	pasemi_nand_mtd->dev.parent = dev;
124
125	chip->IO_ADDR_R = of_iomap(np, 0);
126	chip->IO_ADDR_W = chip->IO_ADDR_R;
127
128	if (!chip->IO_ADDR_R) {
129		err = -EIO;
130		goto out_mtd;
131	}
132
133	pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa008, NULL);
134	if (!pdev) {
135		err = -ENODEV;
136		goto out_ior;
137	}
138
139	lpcctl = pci_resource_start(pdev, 0);
140	pci_dev_put(pdev);
141
142	if (!request_region(lpcctl, 4, driver_name)) {
143		err = -EBUSY;
144		goto out_ior;
145	}
146
147	chip->cmd_ctrl = pasemi_hwcontrol;
148	chip->dev_ready = pasemi_device_ready;
149	chip->read_buf = pasemi_read_buf;
150	chip->write_buf = pasemi_write_buf;
151	chip->chip_delay = 0;
152	chip->ecc.mode = NAND_ECC_SOFT;
153	chip->ecc.algo = NAND_ECC_HAMMING;
154
155	/* Enable the following for a flash based bad block table */
156	chip->bbt_options = NAND_BBT_USE_FLASH;
157
158	/* Scan to find existence of the device */
159	err = nand_scan(pasemi_nand_mtd, 1);
160	if (err)
161		goto out_lpc;
162
163	if (mtd_device_register(pasemi_nand_mtd, NULL, 0)) {
164		dev_err(dev, "Unable to register MTD device\n");
165		err = -ENODEV;
166		goto out_lpc;
167	}
168
169	dev_info(dev, "PA Semi NAND flash at %pR, control at I/O %x\n", &res,
170		 lpcctl);
171
172	return 0;
173
174 out_lpc:
175	release_region(lpcctl, 4);
176 out_ior:
177	iounmap(chip->IO_ADDR_R);
178 out_mtd:
179	kfree(chip);
180 out:
181	return err;
182}
183
184static int pasemi_nand_remove(struct platform_device *ofdev)
185{
186	struct nand_chip *chip;
187
188	if (!pasemi_nand_mtd)
189		return 0;
190
191	chip = mtd_to_nand(pasemi_nand_mtd);
192
193	/* Release resources, unregister device */
194	nand_release(pasemi_nand_mtd);
195
196	release_region(lpcctl, 4);
197
198	iounmap(chip->IO_ADDR_R);
199
200	/* Free the MTD device structure */
201	kfree(chip);
202
203	pasemi_nand_mtd = NULL;
204
205	return 0;
206}
207
208static const struct of_device_id pasemi_nand_match[] =
209{
210	{
211		.compatible   = "pasemi,localbus-nand",
212	},
213	{},
214};
215
216MODULE_DEVICE_TABLE(of, pasemi_nand_match);
217
218static struct platform_driver pasemi_nand_driver =
219{
220	.driver = {
221		.name = driver_name,
222		.of_match_table = pasemi_nand_match,
223	},
224	.probe		= pasemi_nand_probe,
225	.remove		= pasemi_nand_remove,
226};
227
228module_platform_driver(pasemi_nand_driver);
229
230MODULE_LICENSE("GPL");
231MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>");
232MODULE_DESCRIPTION("NAND flash interface driver for PA Semi PWRficient");