mtd: rawnand: pasemi: Keep the driver compatible with on-die ECC engines
[platform/kernel/linux-rpi.git] / drivers / mtd / nand / raw / pasemi_nand.c
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");