2 * NAND flash driver for the MikroTik RouterBOARD 750
4 * Copyright (C) 2010-2012 Gabor Juhos <juhosg@openwrt.org>
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published
8 * by the Free Software Foundation.
11 #include <linux/version.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,14,0)
15 #include <linux/mtd/nand.h>
17 #include <linux/mtd/rawnand.h>
19 #include <linux/mtd/mtd.h>
20 #include <linux/mtd/partitions.h>
21 #include <linux/platform_device.h>
23 #include <linux/slab.h>
25 #include <asm/mach-ath79/ar71xx_regs.h>
26 #include <asm/mach-ath79/ath79.h>
27 #include <asm/mach-ath79/mach-rb750.h>
29 #define DRV_NAME "rb750-nand"
30 #define DRV_VERSION "0.1.0"
31 #define DRV_DESC "NAND flash driver for the RouterBOARD 750"
33 #define RB750_NAND_IO0 BIT(RB750_GPIO_NAND_IO0)
34 #define RB750_NAND_ALE BIT(RB750_GPIO_NAND_ALE)
35 #define RB750_NAND_CLE BIT(RB750_GPIO_NAND_CLE)
36 #define RB750_NAND_NRE BIT(RB750_GPIO_NAND_NRE)
37 #define RB750_NAND_NWE BIT(RB750_GPIO_NAND_NWE)
38 #define RB750_NAND_RDY BIT(RB750_GPIO_NAND_RDY)
40 #define RB750_NAND_DATA_SHIFT 1
41 #define RB750_NAND_DATA_BITS (0xff << RB750_NAND_DATA_SHIFT)
42 #define RB750_NAND_INPUT_BITS (RB750_NAND_DATA_BITS | RB750_NAND_RDY)
43 #define RB750_NAND_OUTPUT_BITS (RB750_NAND_ALE | RB750_NAND_CLE | \
44 RB750_NAND_NRE | RB750_NAND_NWE)
46 struct rb750_nand_info
{
47 struct nand_chip chip
;
48 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
51 struct rb7xx_nand_platform_data
*pdata
;
54 static inline struct rb750_nand_info
*mtd_to_rbinfo(struct mtd_info
*mtd
)
56 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
57 return container_of(mtd
, struct rb750_nand_info
, mtd
);
59 struct nand_chip
*chip
= mtd_to_nand(mtd
);
61 return container_of(chip
, struct rb750_nand_info
, chip
);
65 static struct mtd_info
*rbinfo_to_mtd(struct rb750_nand_info
*nfc
)
67 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
70 return nand_to_mtd(&nfc
->chip
);
74 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
76 * We need to use the OLD Yaffs-1 OOB layout, otherwise the RB bootloader
77 * will not be able to find the kernel that we load.
79 static struct nand_ecclayout rb750_nand_ecclayout
= {
81 .eccpos
= { 8, 9, 10, 13, 14, 15 },
83 .oobfree
= { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } }
88 static int rb750_ooblayout_ecc(struct mtd_info
*mtd
, int section
,
89 struct mtd_oob_region
*oobregion
)
93 oobregion
->offset
= 8;
94 oobregion
->length
= 3;
97 oobregion
->offset
= 13;
98 oobregion
->length
= 3;
105 static int rb750_ooblayout_free(struct mtd_info
*mtd
, int section
,
106 struct mtd_oob_region
*oobregion
)
110 oobregion
->offset
= 0;
111 oobregion
->length
= 4;
114 oobregion
->offset
= 4;
115 oobregion
->length
= 1;
118 oobregion
->offset
= 6;
119 oobregion
->length
= 2;
122 oobregion
->offset
= 11;
123 oobregion
->length
= 2;
130 static const struct mtd_ooblayout_ops rb750_nand_ecclayout_ops
= {
131 .ecc
= rb750_ooblayout_ecc
,
132 .free
= rb750_ooblayout_free
,
136 static struct mtd_partition rb750_nand_partitions
[] = {
140 .size
= (256 * 1024),
141 .mask_flags
= MTD_WRITEABLE
,
144 .offset
= (256 * 1024),
145 .size
= (4 * 1024 * 1024) - (256 * 1024),
148 .offset
= MTDPART_OFS_NXTBLK
,
149 .size
= MTDPART_SIZ_FULL
,
153 static void rb750_nand_write(const u8
*buf
, unsigned len
)
155 void __iomem
*base
= ath79_gpio_base
;
160 /* set data lines to output mode */
161 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
162 __raw_writel(t
| RB750_NAND_DATA_BITS
, base
+ AR71XX_GPIO_REG_OE
);
164 out
= __raw_readl(base
+ AR71XX_GPIO_REG_OUT
);
165 out
&= ~(RB750_NAND_DATA_BITS
| RB750_NAND_NWE
);
166 for (i
= 0; i
!= len
; i
++) {
170 data
<<= RB750_NAND_DATA_SHIFT
;
172 __raw_writel(data
, base
+ AR71XX_GPIO_REG_OUT
);
174 __raw_writel(data
| RB750_NAND_NWE
, base
+ AR71XX_GPIO_REG_OUT
);
176 __raw_readl(base
+ AR71XX_GPIO_REG_OUT
);
179 /* set data lines to input mode */
180 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
181 __raw_writel(t
& ~RB750_NAND_DATA_BITS
, base
+ AR71XX_GPIO_REG_OE
);
183 __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
186 static void rb750_nand_read(u8
*read_buf
, unsigned len
)
188 void __iomem
*base
= ath79_gpio_base
;
191 for (i
= 0; i
< len
; i
++) {
194 /* activate RE line */
195 __raw_writel(RB750_NAND_NRE
, base
+ AR71XX_GPIO_REG_CLEAR
);
197 __raw_readl(base
+ AR71XX_GPIO_REG_CLEAR
);
199 /* read input lines */
200 data
= __raw_readl(base
+ AR71XX_GPIO_REG_IN
) >>
201 RB750_NAND_DATA_SHIFT
;
203 /* deactivate RE line */
204 __raw_writel(RB750_NAND_NRE
, base
+ AR71XX_GPIO_REG_SET
);
210 static void rb750_nand_select_chip(struct mtd_info
*mtd
, int chip
)
212 struct rb750_nand_info
*rbinfo
= mtd_to_rbinfo(mtd
);
213 void __iomem
*base
= ath79_gpio_base
;
217 rbinfo
->pdata
->enable_pins();
219 /* set input mode for data lines */
220 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
221 __raw_writel(t
& ~RB750_NAND_INPUT_BITS
,
222 base
+ AR71XX_GPIO_REG_OE
);
224 /* deactivate RE and WE lines */
225 __raw_writel(RB750_NAND_NRE
| RB750_NAND_NWE
,
226 base
+ AR71XX_GPIO_REG_SET
);
228 (void) __raw_readl(base
+ AR71XX_GPIO_REG_SET
);
230 /* activate CE line */
231 __raw_writel(rbinfo
->pdata
->nce_line
,
232 base
+ AR71XX_GPIO_REG_CLEAR
);
234 /* deactivate CE line */
235 __raw_writel(rbinfo
->pdata
->nce_line
,
236 base
+ AR71XX_GPIO_REG_SET
);
238 (void) __raw_readl(base
+ AR71XX_GPIO_REG_SET
);
240 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
241 __raw_writel(t
| RB750_NAND_IO0
| RB750_NAND_RDY
,
242 base
+ AR71XX_GPIO_REG_OE
);
244 rbinfo
->pdata
->disable_pins();
248 static int rb750_nand_dev_ready(struct mtd_info
*mtd
)
250 void __iomem
*base
= ath79_gpio_base
;
252 return !!(__raw_readl(base
+ AR71XX_GPIO_REG_IN
) & RB750_NAND_RDY
);
255 static void rb750_nand_cmd_ctrl(struct mtd_info
*mtd
, int cmd
,
258 if (ctrl
& NAND_CTRL_CHANGE
) {
259 void __iomem
*base
= ath79_gpio_base
;
262 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OUT
);
264 t
&= ~(RB750_NAND_CLE
| RB750_NAND_ALE
);
265 t
|= (ctrl
& NAND_CLE
) ? RB750_NAND_CLE
: 0;
266 t
|= (ctrl
& NAND_ALE
) ? RB750_NAND_ALE
: 0;
268 __raw_writel(t
, base
+ AR71XX_GPIO_REG_OUT
);
270 __raw_readl(base
+ AR71XX_GPIO_REG_OUT
);
273 if (cmd
!= NAND_CMD_NONE
) {
275 rb750_nand_write(&t
, 1);
279 static u8
rb750_nand_read_byte(struct mtd_info
*mtd
)
282 rb750_nand_read(&data
, 1);
286 static void rb750_nand_read_buf(struct mtd_info
*mtd
, u8
*buf
, int len
)
288 rb750_nand_read(buf
, len
);
291 static void rb750_nand_write_buf(struct mtd_info
*mtd
, const u8
*buf
, int len
)
293 rb750_nand_write(buf
, len
);
296 static void __init
rb750_nand_gpio_init(struct rb750_nand_info
*info
)
298 void __iomem
*base
= ath79_gpio_base
;
302 out
= __raw_readl(base
+ AR71XX_GPIO_REG_OUT
);
304 /* setup output levels */
305 __raw_writel(RB750_NAND_NCE
| RB750_NAND_NRE
| RB750_NAND_NWE
,
306 base
+ AR71XX_GPIO_REG_SET
);
308 __raw_writel(RB750_NAND_ALE
| RB750_NAND_CLE
,
309 base
+ AR71XX_GPIO_REG_CLEAR
);
311 /* setup input lines */
312 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
313 __raw_writel(t
& ~(RB750_NAND_INPUT_BITS
), base
+ AR71XX_GPIO_REG_OE
);
315 /* setup output lines */
316 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
317 t
|= RB750_NAND_OUTPUT_BITS
;
318 t
|= info
->pdata
->nce_line
;
319 __raw_writel(t
, base
+ AR71XX_GPIO_REG_OE
);
321 info
->pdata
->latch_change(~out
& RB750_NAND_IO0
, out
& RB750_NAND_IO0
);
324 static int rb750_nand_probe(struct platform_device
*pdev
)
326 struct rb750_nand_info
*info
;
327 struct rb7xx_nand_platform_data
*pdata
;
328 struct mtd_info
*mtd
;
331 printk(KERN_INFO DRV_DESC
" version " DRV_VERSION
"\n");
333 pdata
= pdev
->dev
.platform_data
;
337 info
= kzalloc(sizeof(*info
), GFP_KERNEL
);
341 info
->chip
.priv
= &info
;
343 mtd
= rbinfo_to_mtd(info
);
344 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
345 mtd
->priv
= &info
->chip
;
347 mtd
->owner
= THIS_MODULE
;
349 info
->chip
.select_chip
= rb750_nand_select_chip
;
350 info
->chip
.cmd_ctrl
= rb750_nand_cmd_ctrl
;
351 info
->chip
.dev_ready
= rb750_nand_dev_ready
;
352 info
->chip
.read_byte
= rb750_nand_read_byte
;
353 info
->chip
.write_buf
= rb750_nand_write_buf
;
354 info
->chip
.read_buf
= rb750_nand_read_buf
;
356 info
->chip
.chip_delay
= 25;
357 info
->chip
.ecc
.mode
= NAND_ECC_SOFT
;
358 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4,6,0)
359 info
->chip
.ecc
.algo
= NAND_ECC_HAMMING
;
361 info
->chip
.options
= NAND_NO_SUBPAGE_WRITE
;
365 platform_set_drvdata(pdev
, info
);
367 rb750_nand_gpio_init(info
);
369 ret
= nand_scan_ident(mtd
, 1, NULL
);
375 if (mtd
->writesize
== 512)
376 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
377 info
->chip
.ecc
.layout
= &rb750_nand_ecclayout
;
379 mtd_set_ooblayout(mtd
, &rb750_nand_ecclayout_ops
);
382 ret
= nand_scan_tail(mtd
);
385 goto err_set_drvdata
;
388 ret
= mtd_device_register(mtd
, rb750_nand_partitions
,
389 ARRAY_SIZE(rb750_nand_partitions
));
391 goto err_release_nand
;
398 platform_set_drvdata(pdev
, NULL
);
404 static int rb750_nand_remove(struct platform_device
*pdev
)
406 struct rb750_nand_info
*info
= platform_get_drvdata(pdev
);
408 nand_release(rbinfo_to_mtd(info
));
409 platform_set_drvdata(pdev
, NULL
);
415 static struct platform_driver rb750_nand_driver
= {
416 .probe
= rb750_nand_probe
,
417 .remove
= rb750_nand_remove
,
420 .owner
= THIS_MODULE
,
424 static int __init
rb750_nand_init(void)
426 return platform_driver_register(&rb750_nand_driver
);
429 static void __exit
rb750_nand_exit(void)
431 platform_driver_unregister(&rb750_nand_driver
);
434 module_init(rb750_nand_init
);
435 module_exit(rb750_nand_exit
);
437 MODULE_DESCRIPTION(DRV_DESC
);
438 MODULE_VERSION(DRV_VERSION
);
439 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
440 MODULE_LICENSE("GPL v2");