xref: /openbmc/linux/drivers/mtd/nand/raw/pasemi_nand.c (revision 5c816641)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2006-2007 PA Semi, Inc
4  *
5  * Author: Egor Martovetsky <egor@pasemi.com>
6  * Maintained by: Olof Johansson <olof@lixom.net>
7  *
8  * Driver for the PWRficient onchip NAND flash interface
9  */
10 
11 #undef DEBUG
12 
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/mtd/mtd.h>
16 #include <linux/mtd/rawnand.h>
17 #include <linux/of_address.h>
18 #include <linux/of_irq.h>
19 #include <linux/of_platform.h>
20 #include <linux/platform_device.h>
21 #include <linux/pci.h>
22 
23 #include <asm/io.h>
24 
25 #define LBICTRL_LPCCTL_NR		0x00004000
26 #define CLE_PIN_CTL			15
27 #define ALE_PIN_CTL			14
28 
29 static unsigned int lpcctl;
30 static struct mtd_info *pasemi_nand_mtd;
31 static struct nand_controller controller;
32 static const char driver_name[] = "pasemi-nand";
33 
34 static void pasemi_read_buf(struct nand_chip *chip, u_char *buf, int len)
35 {
36 	while (len > 0x800) {
37 		memcpy_fromio(buf, chip->legacy.IO_ADDR_R, 0x800);
38 		buf += 0x800;
39 		len -= 0x800;
40 	}
41 	memcpy_fromio(buf, chip->legacy.IO_ADDR_R, len);
42 }
43 
44 static void pasemi_write_buf(struct nand_chip *chip, const u_char *buf,
45 			     int len)
46 {
47 	while (len > 0x800) {
48 		memcpy_toio(chip->legacy.IO_ADDR_R, buf, 0x800);
49 		buf += 0x800;
50 		len -= 0x800;
51 	}
52 	memcpy_toio(chip->legacy.IO_ADDR_R, buf, len);
53 }
54 
55 static void pasemi_hwcontrol(struct nand_chip *chip, int cmd,
56 			     unsigned int ctrl)
57 {
58 	if (cmd == NAND_CMD_NONE)
59 		return;
60 
61 	if (ctrl & NAND_CLE)
62 		out_8(chip->legacy.IO_ADDR_W + (1 << CLE_PIN_CTL), cmd);
63 	else
64 		out_8(chip->legacy.IO_ADDR_W + (1 << ALE_PIN_CTL), cmd);
65 
66 	/* Push out posted writes */
67 	eieio();
68 	inl(lpcctl);
69 }
70 
71 static int pasemi_device_ready(struct nand_chip *chip)
72 {
73 	return !!(inl(lpcctl) & LBICTRL_LPCCTL_NR);
74 }
75 
76 static int pasemi_attach_chip(struct nand_chip *chip)
77 {
78 	if (chip->ecc.engine_type == NAND_ECC_ENGINE_TYPE_SOFT &&
79 	    chip->ecc.algo == NAND_ECC_ALGO_UNKNOWN)
80 		chip->ecc.algo = NAND_ECC_ALGO_HAMMING;
81 
82 	return 0;
83 }
84 
85 static const struct nand_controller_ops pasemi_ops = {
86 	.attach_chip = pasemi_attach_chip,
87 };
88 
89 static int pasemi_nand_probe(struct platform_device *ofdev)
90 {
91 	struct device *dev = &ofdev->dev;
92 	struct pci_dev *pdev;
93 	struct device_node *np = dev->of_node;
94 	struct resource res;
95 	struct nand_chip *chip;
96 	int err = 0;
97 
98 	err = of_address_to_resource(np, 0, &res);
99 
100 	if (err)
101 		return -EINVAL;
102 
103 	/* We only support one device at the moment */
104 	if (pasemi_nand_mtd)
105 		return -ENODEV;
106 
107 	dev_dbg(dev, "pasemi_nand at %pR\n", &res);
108 
109 	/* Allocate memory for MTD device structure and private data */
110 	chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
111 	if (!chip) {
112 		err = -ENOMEM;
113 		goto out;
114 	}
115 
116 	controller.ops = &pasemi_ops;
117 	nand_controller_init(&controller);
118 	chip->controller = &controller;
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->legacy.IO_ADDR_R = of_iomap(np, 0);
126 	chip->legacy.IO_ADDR_W = chip->legacy.IO_ADDR_R;
127 
128 	if (!chip->legacy.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->legacy.cmd_ctrl = pasemi_hwcontrol;
148 	chip->legacy.dev_ready = pasemi_device_ready;
149 	chip->legacy.read_buf = pasemi_read_buf;
150 	chip->legacy.write_buf = pasemi_write_buf;
151 	chip->legacy.chip_delay = 0;
152 
153 	/* Enable the following for a flash based bad block table */
154 	chip->bbt_options = NAND_BBT_USE_FLASH;
155 
156 	/*
157 	 * This driver assumes that the default ECC engine should be TYPE_SOFT.
158 	 * Set ->engine_type before registering the NAND devices in order to
159 	 * provide a driver specific default value.
160 	 */
161 	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
162 
163 	/* Scan to find existence of the device */
164 	err = nand_scan(chip, 1);
165 	if (err)
166 		goto out_lpc;
167 
168 	if (mtd_device_register(pasemi_nand_mtd, NULL, 0)) {
169 		dev_err(dev, "Unable to register MTD device\n");
170 		err = -ENODEV;
171 		goto out_cleanup_nand;
172 	}
173 
174 	dev_info(dev, "PA Semi NAND flash at %pR, control at I/O %x\n", &res,
175 		 lpcctl);
176 
177 	return 0;
178 
179  out_cleanup_nand:
180 	nand_cleanup(chip);
181  out_lpc:
182 	release_region(lpcctl, 4);
183  out_ior:
184 	iounmap(chip->legacy.IO_ADDR_R);
185  out_mtd:
186 	kfree(chip);
187  out:
188 	return err;
189 }
190 
191 static int pasemi_nand_remove(struct platform_device *ofdev)
192 {
193 	struct nand_chip *chip;
194 	int ret;
195 
196 	if (!pasemi_nand_mtd)
197 		return 0;
198 
199 	chip = mtd_to_nand(pasemi_nand_mtd);
200 
201 	/* Release resources, unregister device */
202 	ret = mtd_device_unregister(pasemi_nand_mtd);
203 	WARN_ON(ret);
204 	nand_cleanup(chip);
205 
206 	release_region(lpcctl, 4);
207 
208 	iounmap(chip->legacy.IO_ADDR_R);
209 
210 	/* Free the MTD device structure */
211 	kfree(chip);
212 
213 	pasemi_nand_mtd = NULL;
214 
215 	return 0;
216 }
217 
218 static const struct of_device_id pasemi_nand_match[] =
219 {
220 	{
221 		.compatible   = "pasemi,localbus-nand",
222 	},
223 	{},
224 };
225 
226 MODULE_DEVICE_TABLE(of, pasemi_nand_match);
227 
228 static struct platform_driver pasemi_nand_driver =
229 {
230 	.driver = {
231 		.name = driver_name,
232 		.of_match_table = pasemi_nand_match,
233 	},
234 	.probe		= pasemi_nand_probe,
235 	.remove		= pasemi_nand_remove,
236 };
237 
238 module_platform_driver(pasemi_nand_driver);
239 
240 MODULE_LICENSE("GPL");
241 MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>");
242 MODULE_DESCRIPTION("NAND flash interface driver for PA Semi PWRficient");
243