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/kernel.h>
12 #include <linux/module.h>
13 #include <linux/mtd/rawnand.h>
14 #include <linux/mtd/mtd.h>
15 #include <linux/mtd/partitions.h>
16 #include <linux/platform_device.h>
18 #include <linux/slab.h>
19 #include <linux/version.h>
21 #include <asm/mach-ath79/ar71xx_regs.h>
22 #include <asm/mach-ath79/ath79.h>
23 #include <asm/mach-ath79/mach-rb750.h>
25 #define DRV_NAME "rb750-nand"
26 #define DRV_VERSION "0.1.0"
27 #define DRV_DESC "NAND flash driver for the RouterBOARD 750"
29 #define RB750_NAND_IO0 BIT(RB750_GPIO_NAND_IO0)
30 #define RB750_NAND_ALE BIT(RB750_GPIO_NAND_ALE)
31 #define RB750_NAND_CLE BIT(RB750_GPIO_NAND_CLE)
32 #define RB750_NAND_NRE BIT(RB750_GPIO_NAND_NRE)
33 #define RB750_NAND_NWE BIT(RB750_GPIO_NAND_NWE)
34 #define RB750_NAND_RDY BIT(RB750_GPIO_NAND_RDY)
36 #define RB750_NAND_DATA_SHIFT 1
37 #define RB750_NAND_DATA_BITS (0xff << RB750_NAND_DATA_SHIFT)
38 #define RB750_NAND_INPUT_BITS (RB750_NAND_DATA_BITS | RB750_NAND_RDY)
39 #define RB750_NAND_OUTPUT_BITS (RB750_NAND_ALE | RB750_NAND_CLE | \
40 RB750_NAND_NRE | RB750_NAND_NWE)
42 struct rb750_nand_info
{
43 struct nand_chip chip
;
44 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
47 struct rb7xx_nand_platform_data
*pdata
;
50 static inline struct rb750_nand_info
*mtd_to_rbinfo(struct mtd_info
*mtd
)
52 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
53 return container_of(mtd
, struct rb750_nand_info
, mtd
);
55 struct nand_chip
*chip
= mtd_to_nand(mtd
);
57 return container_of(chip
, struct rb750_nand_info
, chip
);
61 static struct mtd_info
*rbinfo_to_mtd(struct rb750_nand_info
*nfc
)
63 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
66 return nand_to_mtd(&nfc
->chip
);
70 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
72 * We need to use the OLD Yaffs-1 OOB layout, otherwise the RB bootloader
73 * will not be able to find the kernel that we load.
75 static struct nand_ecclayout rb750_nand_ecclayout
= {
77 .eccpos
= { 8, 9, 10, 13, 14, 15 },
79 .oobfree
= { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } }
84 static int rb750_ooblayout_ecc(struct mtd_info
*mtd
, int section
,
85 struct mtd_oob_region
*oobregion
)
89 oobregion
->offset
= 8;
90 oobregion
->length
= 3;
93 oobregion
->offset
= 13;
94 oobregion
->length
= 3;
101 static int rb750_ooblayout_free(struct mtd_info
*mtd
, int section
,
102 struct mtd_oob_region
*oobregion
)
106 oobregion
->offset
= 0;
107 oobregion
->length
= 4;
110 oobregion
->offset
= 4;
111 oobregion
->length
= 1;
114 oobregion
->offset
= 6;
115 oobregion
->length
= 2;
118 oobregion
->offset
= 11;
119 oobregion
->length
= 2;
126 static const struct mtd_ooblayout_ops rb750_nand_ecclayout_ops
= {
127 .ecc
= rb750_ooblayout_ecc
,
128 .free
= rb750_ooblayout_free
,
132 static struct mtd_partition rb750_nand_partitions
[] = {
136 .size
= (256 * 1024),
137 .mask_flags
= MTD_WRITEABLE
,
140 .offset
= (256 * 1024),
141 .size
= (4 * 1024 * 1024) - (256 * 1024),
144 .offset
= MTDPART_OFS_NXTBLK
,
145 .size
= MTDPART_SIZ_FULL
,
149 static void rb750_nand_write(const u8
*buf
, unsigned len
)
151 void __iomem
*base
= ath79_gpio_base
;
156 /* set data lines to output mode */
157 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
158 __raw_writel(t
| RB750_NAND_DATA_BITS
, base
+ AR71XX_GPIO_REG_OE
);
160 out
= __raw_readl(base
+ AR71XX_GPIO_REG_OUT
);
161 out
&= ~(RB750_NAND_DATA_BITS
| RB750_NAND_NWE
);
162 for (i
= 0; i
!= len
; i
++) {
166 data
<<= RB750_NAND_DATA_SHIFT
;
168 __raw_writel(data
, base
+ AR71XX_GPIO_REG_OUT
);
170 __raw_writel(data
| RB750_NAND_NWE
, base
+ AR71XX_GPIO_REG_OUT
);
172 __raw_readl(base
+ AR71XX_GPIO_REG_OUT
);
175 /* set data lines to input mode */
176 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
177 __raw_writel(t
& ~RB750_NAND_DATA_BITS
, base
+ AR71XX_GPIO_REG_OE
);
179 __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
182 static void rb750_nand_read(u8
*read_buf
, unsigned len
)
184 void __iomem
*base
= ath79_gpio_base
;
187 for (i
= 0; i
< len
; i
++) {
190 /* activate RE line */
191 __raw_writel(RB750_NAND_NRE
, base
+ AR71XX_GPIO_REG_CLEAR
);
193 __raw_readl(base
+ AR71XX_GPIO_REG_CLEAR
);
195 /* read input lines */
196 data
= __raw_readl(base
+ AR71XX_GPIO_REG_IN
) >>
197 RB750_NAND_DATA_SHIFT
;
199 /* deactivate RE line */
200 __raw_writel(RB750_NAND_NRE
, base
+ AR71XX_GPIO_REG_SET
);
206 static void rb750_nand_select_chip(struct mtd_info
*mtd
, int chip
)
208 struct rb750_nand_info
*rbinfo
= mtd_to_rbinfo(mtd
);
209 void __iomem
*base
= ath79_gpio_base
;
213 rbinfo
->pdata
->enable_pins();
215 /* set input mode for data lines */
216 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
217 __raw_writel(t
& ~RB750_NAND_INPUT_BITS
,
218 base
+ AR71XX_GPIO_REG_OE
);
220 /* deactivate RE and WE lines */
221 __raw_writel(RB750_NAND_NRE
| RB750_NAND_NWE
,
222 base
+ AR71XX_GPIO_REG_SET
);
224 (void) __raw_readl(base
+ AR71XX_GPIO_REG_SET
);
226 /* activate CE line */
227 __raw_writel(rbinfo
->pdata
->nce_line
,
228 base
+ AR71XX_GPIO_REG_CLEAR
);
230 /* deactivate CE line */
231 __raw_writel(rbinfo
->pdata
->nce_line
,
232 base
+ AR71XX_GPIO_REG_SET
);
234 (void) __raw_readl(base
+ AR71XX_GPIO_REG_SET
);
236 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
237 __raw_writel(t
| RB750_NAND_IO0
| RB750_NAND_RDY
,
238 base
+ AR71XX_GPIO_REG_OE
);
240 rbinfo
->pdata
->disable_pins();
244 static int rb750_nand_dev_ready(struct mtd_info
*mtd
)
246 void __iomem
*base
= ath79_gpio_base
;
248 return !!(__raw_readl(base
+ AR71XX_GPIO_REG_IN
) & RB750_NAND_RDY
);
251 static void rb750_nand_cmd_ctrl(struct mtd_info
*mtd
, int cmd
,
254 if (ctrl
& NAND_CTRL_CHANGE
) {
255 void __iomem
*base
= ath79_gpio_base
;
258 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OUT
);
260 t
&= ~(RB750_NAND_CLE
| RB750_NAND_ALE
);
261 t
|= (ctrl
& NAND_CLE
) ? RB750_NAND_CLE
: 0;
262 t
|= (ctrl
& NAND_ALE
) ? RB750_NAND_ALE
: 0;
264 __raw_writel(t
, base
+ AR71XX_GPIO_REG_OUT
);
266 __raw_readl(base
+ AR71XX_GPIO_REG_OUT
);
269 if (cmd
!= NAND_CMD_NONE
) {
271 rb750_nand_write(&t
, 1);
275 static u8
rb750_nand_read_byte(struct mtd_info
*mtd
)
278 rb750_nand_read(&data
, 1);
282 static void rb750_nand_read_buf(struct mtd_info
*mtd
, u8
*buf
, int len
)
284 rb750_nand_read(buf
, len
);
287 static void rb750_nand_write_buf(struct mtd_info
*mtd
, const u8
*buf
, int len
)
289 rb750_nand_write(buf
, len
);
292 static void __init
rb750_nand_gpio_init(struct rb750_nand_info
*info
)
294 void __iomem
*base
= ath79_gpio_base
;
298 out
= __raw_readl(base
+ AR71XX_GPIO_REG_OUT
);
300 /* setup output levels */
301 __raw_writel(RB750_NAND_NCE
| RB750_NAND_NRE
| RB750_NAND_NWE
,
302 base
+ AR71XX_GPIO_REG_SET
);
304 __raw_writel(RB750_NAND_ALE
| RB750_NAND_CLE
,
305 base
+ AR71XX_GPIO_REG_CLEAR
);
307 /* setup input lines */
308 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
309 __raw_writel(t
& ~(RB750_NAND_INPUT_BITS
), base
+ AR71XX_GPIO_REG_OE
);
311 /* setup output lines */
312 t
= __raw_readl(base
+ AR71XX_GPIO_REG_OE
);
313 t
|= RB750_NAND_OUTPUT_BITS
;
314 t
|= info
->pdata
->nce_line
;
315 __raw_writel(t
, base
+ AR71XX_GPIO_REG_OE
);
317 info
->pdata
->latch_change(~out
& RB750_NAND_IO0
, out
& RB750_NAND_IO0
);
320 static int rb750_nand_probe(struct platform_device
*pdev
)
322 struct rb750_nand_info
*info
;
323 struct rb7xx_nand_platform_data
*pdata
;
324 struct mtd_info
*mtd
;
327 printk(KERN_INFO DRV_DESC
" version " DRV_VERSION
"\n");
329 pdata
= pdev
->dev
.platform_data
;
333 info
= kzalloc(sizeof(*info
), GFP_KERNEL
);
337 info
->chip
.priv
= &info
;
339 mtd
= rbinfo_to_mtd(info
);
340 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
341 mtd
->priv
= &info
->chip
;
343 mtd
->owner
= THIS_MODULE
;
345 info
->chip
.select_chip
= rb750_nand_select_chip
;
346 info
->chip
.cmd_ctrl
= rb750_nand_cmd_ctrl
;
347 info
->chip
.dev_ready
= rb750_nand_dev_ready
;
348 info
->chip
.read_byte
= rb750_nand_read_byte
;
349 info
->chip
.write_buf
= rb750_nand_write_buf
;
350 info
->chip
.read_buf
= rb750_nand_read_buf
;
352 info
->chip
.chip_delay
= 25;
353 info
->chip
.ecc
.mode
= NAND_ECC_SOFT
;
354 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4,6,0)
355 info
->chip
.ecc
.algo
= NAND_ECC_HAMMING
;
357 info
->chip
.options
= NAND_NO_SUBPAGE_WRITE
;
361 platform_set_drvdata(pdev
, info
);
363 rb750_nand_gpio_init(info
);
365 ret
= nand_scan_ident(mtd
, 1, NULL
);
371 if (mtd
->writesize
== 512)
372 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
373 info
->chip
.ecc
.layout
= &rb750_nand_ecclayout
;
375 mtd_set_ooblayout(mtd
, &rb750_nand_ecclayout_ops
);
378 ret
= nand_scan_tail(mtd
);
381 goto err_set_drvdata
;
384 ret
= mtd_device_register(mtd
, rb750_nand_partitions
,
385 ARRAY_SIZE(rb750_nand_partitions
));
387 goto err_release_nand
;
394 platform_set_drvdata(pdev
, NULL
);
400 static int rb750_nand_remove(struct platform_device
*pdev
)
402 struct rb750_nand_info
*info
= platform_get_drvdata(pdev
);
404 nand_release(rbinfo_to_mtd(info
));
405 platform_set_drvdata(pdev
, NULL
);
411 static struct platform_driver rb750_nand_driver
= {
412 .probe
= rb750_nand_probe
,
413 .remove
= rb750_nand_remove
,
416 .owner
= THIS_MODULE
,
420 static int __init
rb750_nand_init(void)
422 return platform_driver_register(&rb750_nand_driver
);
425 static void __exit
rb750_nand_exit(void)
427 platform_driver_unregister(&rb750_nand_driver
);
430 module_init(rb750_nand_init
);
431 module_exit(rb750_nand_exit
);
433 MODULE_DESCRIPTION(DRV_DESC
);
434 MODULE_VERSION(DRV_VERSION
);
435 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
436 MODULE_LICENSE("GPL v2");