2 * drivers/mtd/nand/au1550nd.c
4 * Copyright (C) 2004 Embedded Edge, LLC
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
12 #include <linux/slab.h>
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/interrupt.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/mtd/nand.h>
18 #include <linux/mtd/partitions.h>
21 #include <asm/mach-au1x00/au1xxx.h>
24 * MTD structure for NAND controller
26 static struct mtd_info
*au1550_mtd
= NULL
;
27 static void __iomem
*p_nand
;
28 static int nand_width
= 1; /* default x8 */
29 static void (*au1550_write_byte
)(struct mtd_info
*, u_char
);
32 * Define partitions for flash device
34 static const struct mtd_partition partition_info
[] = {
38 .size
= 8 * 1024 * 1024},
41 .offset
= MTDPART_OFS_APPEND
,
42 .size
= MTDPART_SIZ_FULL
}
46 * au_read_byte - read one byte from the chip
47 * @mtd: MTD device structure
49 * read function for 8bit buswith
51 static u_char
au_read_byte(struct mtd_info
*mtd
)
53 struct nand_chip
*this = mtd
->priv
;
54 u_char ret
= readb(this->IO_ADDR_R
);
60 * au_write_byte - write one byte to the chip
61 * @mtd: MTD device structure
62 * @byte: pointer to data byte to write
64 * write function for 8it buswith
66 static void au_write_byte(struct mtd_info
*mtd
, u_char byte
)
68 struct nand_chip
*this = mtd
->priv
;
69 writeb(byte
, this->IO_ADDR_W
);
74 * au_read_byte16 - read one byte endianess aware from the chip
75 * @mtd: MTD device structure
77 * read function for 16bit buswith with
78 * endianess conversion
80 static u_char
au_read_byte16(struct mtd_info
*mtd
)
82 struct nand_chip
*this = mtd
->priv
;
83 u_char ret
= (u_char
) cpu_to_le16(readw(this->IO_ADDR_R
));
89 * au_write_byte16 - write one byte endianess aware to the chip
90 * @mtd: MTD device structure
91 * @byte: pointer to data byte to write
93 * write function for 16bit buswith with
94 * endianess conversion
96 static void au_write_byte16(struct mtd_info
*mtd
, u_char byte
)
98 struct nand_chip
*this = mtd
->priv
;
99 writew(le16_to_cpu((u16
) byte
), this->IO_ADDR_W
);
104 * au_read_word - read one word from the chip
105 * @mtd: MTD device structure
107 * read function for 16bit buswith without
108 * endianess conversion
110 static u16
au_read_word(struct mtd_info
*mtd
)
112 struct nand_chip
*this = mtd
->priv
;
113 u16 ret
= readw(this->IO_ADDR_R
);
119 * au_write_buf - write buffer to chip
120 * @mtd: MTD device structure
122 * @len: number of bytes to write
124 * write function for 8bit buswith
126 static void au_write_buf(struct mtd_info
*mtd
, const u_char
*buf
, int len
)
129 struct nand_chip
*this = mtd
->priv
;
131 for (i
= 0; i
< len
; i
++) {
132 writeb(buf
[i
], this->IO_ADDR_W
);
138 * au_read_buf - read chip data into buffer
139 * @mtd: MTD device structure
140 * @buf: buffer to store date
141 * @len: number of bytes to read
143 * read function for 8bit buswith
145 static void au_read_buf(struct mtd_info
*mtd
, u_char
*buf
, int len
)
148 struct nand_chip
*this = mtd
->priv
;
150 for (i
= 0; i
< len
; i
++) {
151 buf
[i
] = readb(this->IO_ADDR_R
);
157 * au_verify_buf - Verify chip data against buffer
158 * @mtd: MTD device structure
159 * @buf: buffer containing the data to compare
160 * @len: number of bytes to compare
162 * verify function for 8bit buswith
164 static int au_verify_buf(struct mtd_info
*mtd
, const u_char
*buf
, int len
)
167 struct nand_chip
*this = mtd
->priv
;
169 for (i
= 0; i
< len
; i
++) {
170 if (buf
[i
] != readb(this->IO_ADDR_R
))
179 * au_write_buf16 - write buffer to chip
180 * @mtd: MTD device structure
182 * @len: number of bytes to write
184 * write function for 16bit buswith
186 static void au_write_buf16(struct mtd_info
*mtd
, const u_char
*buf
, int len
)
189 struct nand_chip
*this = mtd
->priv
;
190 u16
*p
= (u16
*) buf
;
193 for (i
= 0; i
< len
; i
++) {
194 writew(p
[i
], this->IO_ADDR_W
);
201 * au_read_buf16 - read chip data into buffer
202 * @mtd: MTD device structure
203 * @buf: buffer to store date
204 * @len: number of bytes to read
206 * read function for 16bit buswith
208 static void au_read_buf16(struct mtd_info
*mtd
, u_char
*buf
, int len
)
211 struct nand_chip
*this = mtd
->priv
;
212 u16
*p
= (u16
*) buf
;
215 for (i
= 0; i
< len
; i
++) {
216 p
[i
] = readw(this->IO_ADDR_R
);
222 * au_verify_buf16 - Verify chip data against buffer
223 * @mtd: MTD device structure
224 * @buf: buffer containing the data to compare
225 * @len: number of bytes to compare
227 * verify function for 16bit buswith
229 static int au_verify_buf16(struct mtd_info
*mtd
, const u_char
*buf
, int len
)
232 struct nand_chip
*this = mtd
->priv
;
233 u16
*p
= (u16
*) buf
;
236 for (i
= 0; i
< len
; i
++) {
237 if (p
[i
] != readw(this->IO_ADDR_R
))
244 /* Select the chip by setting nCE to low */
245 #define NAND_CTL_SETNCE 1
246 /* Deselect the chip by setting nCE to high */
247 #define NAND_CTL_CLRNCE 2
248 /* Select the command latch by setting CLE to high */
249 #define NAND_CTL_SETCLE 3
250 /* Deselect the command latch by setting CLE to low */
251 #define NAND_CTL_CLRCLE 4
252 /* Select the address latch by setting ALE to high */
253 #define NAND_CTL_SETALE 5
254 /* Deselect the address latch by setting ALE to low */
255 #define NAND_CTL_CLRALE 6
257 static void au1550_hwcontrol(struct mtd_info
*mtd
, int cmd
)
259 register struct nand_chip
*this = mtd
->priv
;
263 case NAND_CTL_SETCLE
:
264 this->IO_ADDR_W
= p_nand
+ MEM_STNAND_CMD
;
267 case NAND_CTL_CLRCLE
:
268 this->IO_ADDR_W
= p_nand
+ MEM_STNAND_DATA
;
271 case NAND_CTL_SETALE
:
272 this->IO_ADDR_W
= p_nand
+ MEM_STNAND_ADDR
;
275 case NAND_CTL_CLRALE
:
276 this->IO_ADDR_W
= p_nand
+ MEM_STNAND_DATA
;
277 /* FIXME: Nobody knows why this is necessary,
278 * but it works only that way */
282 case NAND_CTL_SETNCE
:
283 /* assert (force assert) chip enable */
284 au_writel((1 << (4 + NAND_CS
)), MEM_STNDCTL
);
287 case NAND_CTL_CLRNCE
:
288 /* deassert chip enable */
289 au_writel(0, MEM_STNDCTL
);
293 this->IO_ADDR_R
= this->IO_ADDR_W
;
295 /* Drain the writebuffer */
299 int au1550_device_ready(struct mtd_info
*mtd
)
301 int ret
= (au_readl(MEM_STSTAT
) & 0x1) ? 1 : 0;
307 * au1550_select_chip - control -CE line
308 * Forbid driving -CE manually permitting the NAND controller to do this.
309 * Keeping -CE asserted during the whole sector reads interferes with the
310 * NOR flash and PCMCIA drivers as it causes contention on the static bus.
311 * We only have to hold -CE low for the NAND read commands since the flash
312 * chip needs it to be asserted during chip not ready time but the NAND
313 * controller keeps it released.
315 * @mtd: MTD device structure
316 * @chip: chipnumber to select, -1 for deselect
318 static void au1550_select_chip(struct mtd_info
*mtd
, int chip
)
323 * au1550_command - Send command to NAND device
324 * @mtd: MTD device structure
325 * @command: the command to be sent
326 * @column: the column address for this command, -1 if none
327 * @page_addr: the page address for this command, -1 if none
329 static void au1550_command(struct mtd_info
*mtd
, unsigned command
, int column
, int page_addr
)
331 register struct nand_chip
*this = mtd
->priv
;
332 int ce_override
= 0, i
;
335 /* Begin command latch cycle */
336 au1550_hwcontrol(mtd
, NAND_CTL_SETCLE
);
338 * Write out the command to the device.
340 if (command
== NAND_CMD_SEQIN
) {
343 if (column
>= mtd
->writesize
) {
345 column
-= mtd
->writesize
;
346 readcmd
= NAND_CMD_READOOB
;
347 } else if (column
< 256) {
348 /* First 256 bytes --> READ0 */
349 readcmd
= NAND_CMD_READ0
;
352 readcmd
= NAND_CMD_READ1
;
354 au1550_write_byte(mtd
, readcmd
);
356 au1550_write_byte(mtd
, command
);
358 /* Set ALE and clear CLE to start address cycle */
359 au1550_hwcontrol(mtd
, NAND_CTL_CLRCLE
);
361 if (column
!= -1 || page_addr
!= -1) {
362 au1550_hwcontrol(mtd
, NAND_CTL_SETALE
);
364 /* Serially input address */
366 /* Adjust columns for 16 bit buswidth */
367 if (this->options
& NAND_BUSWIDTH_16
)
369 au1550_write_byte(mtd
, column
);
371 if (page_addr
!= -1) {
372 au1550_write_byte(mtd
, (u8
)(page_addr
& 0xff));
374 if (command
== NAND_CMD_READ0
||
375 command
== NAND_CMD_READ1
||
376 command
== NAND_CMD_READOOB
) {
378 * NAND controller will release -CE after
379 * the last address byte is written, so we'll
380 * have to forcibly assert it. No interrupts
381 * are allowed while we do this as we don't
382 * want the NOR flash or PCMCIA drivers to
383 * steal our precious bytes of data...
386 local_irq_save(flags
);
387 au1550_hwcontrol(mtd
, NAND_CTL_SETNCE
);
390 au1550_write_byte(mtd
, (u8
)(page_addr
>> 8));
392 /* One more address cycle for devices > 32MiB */
393 if (this->chipsize
> (32 << 20))
394 au1550_write_byte(mtd
, (u8
)((page_addr
>> 16) & 0x0f));
396 /* Latch in address */
397 au1550_hwcontrol(mtd
, NAND_CTL_CLRALE
);
401 * Program and erase have their own busy handlers.
402 * Status and sequential in need no delay.
406 case NAND_CMD_PAGEPROG
:
407 case NAND_CMD_ERASE1
:
408 case NAND_CMD_ERASE2
:
410 case NAND_CMD_STATUS
:
418 case NAND_CMD_READOOB
:
419 /* Check if we're really driving -CE low (just in case) */
420 if (unlikely(!ce_override
))
423 /* Apply a short delay always to ensure that we do wait tWB. */
425 /* Wait for a chip to become ready... */
426 for (i
= this->chip_delay
; !this->dev_ready(mtd
) && i
> 0; --i
)
429 /* Release -CE and re-enable interrupts. */
430 au1550_hwcontrol(mtd
, NAND_CTL_CLRNCE
);
431 local_irq_restore(flags
);
434 /* Apply this short delay always to ensure that we do wait tWB. */
437 while(!this->dev_ready(mtd
));
442 * Main initialization routine
444 static int __init
au1xxx_nand_init(void)
446 struct nand_chip
*this;
447 u16 boot_swapboot
= 0; /* default value */
452 /* Allocate memory for MTD device structure and private data */
453 au1550_mtd
= kmalloc(sizeof(struct mtd_info
) + sizeof(struct nand_chip
), GFP_KERNEL
);
455 printk("Unable to allocate NAND MTD dev structure.\n");
459 /* Get pointer to private data */
460 this = (struct nand_chip
*)(&au1550_mtd
[1]);
462 /* Initialize structures */
463 memset(au1550_mtd
, 0, sizeof(struct mtd_info
));
464 memset(this, 0, sizeof(struct nand_chip
));
466 /* Link the private data with the MTD structure */
467 au1550_mtd
->priv
= this;
468 au1550_mtd
->owner
= THIS_MODULE
;
471 /* MEM_STNDCTL: disable ints, disable nand boot */
472 au_writel(0, MEM_STNDCTL
);
474 #ifdef CONFIG_MIPS_PB1550
475 /* set gpio206 high */
476 au_writel(au_readl(GPIO2_DIR
) & ~(1 << 6), GPIO2_DIR
);
478 boot_swapboot
= (au_readl(MEM_STSTAT
) & (0x7 << 1)) | ((bcsr
->status
>> 6) & 0x1);
479 switch (boot_swapboot
) {
497 printk("Pb1550 NAND: bad boot:swap\n");
503 /* Configure chip-select; normally done by boot code, e.g. YAMON */
506 au_writel(NAND_STCFG
, MEM_STCFG0
);
507 au_writel(NAND_STTIME
, MEM_STTIME0
);
508 au_writel(NAND_STADDR
, MEM_STADDR0
);
511 au_writel(NAND_STCFG
, MEM_STCFG1
);
512 au_writel(NAND_STTIME
, MEM_STTIME1
);
513 au_writel(NAND_STADDR
, MEM_STADDR1
);
516 au_writel(NAND_STCFG
, MEM_STCFG2
);
517 au_writel(NAND_STTIME
, MEM_STTIME2
);
518 au_writel(NAND_STADDR
, MEM_STADDR2
);
521 au_writel(NAND_STCFG
, MEM_STCFG3
);
522 au_writel(NAND_STTIME
, MEM_STTIME3
);
523 au_writel(NAND_STADDR
, MEM_STADDR3
);
527 /* Locate NAND chip-select in order to determine NAND phys address */
528 mem_staddr
= 0x00000000;
529 if (((au_readl(MEM_STCFG0
) & 0x7) == 0x5) && (NAND_CS
== 0))
530 mem_staddr
= au_readl(MEM_STADDR0
);
531 else if (((au_readl(MEM_STCFG1
) & 0x7) == 0x5) && (NAND_CS
== 1))
532 mem_staddr
= au_readl(MEM_STADDR1
);
533 else if (((au_readl(MEM_STCFG2
) & 0x7) == 0x5) && (NAND_CS
== 2))
534 mem_staddr
= au_readl(MEM_STADDR2
);
535 else if (((au_readl(MEM_STCFG3
) & 0x7) == 0x5) && (NAND_CS
== 3))
536 mem_staddr
= au_readl(MEM_STADDR3
);
538 if (mem_staddr
== 0x00000000) {
539 printk("Au1xxx NAND: ERROR WITH NAND CHIP-SELECT\n");
543 nand_phys
= (mem_staddr
<< 4) & 0xFFFC0000;
545 p_nand
= (void __iomem
*)ioremap(nand_phys
, 0x1000);
547 /* make controller and MTD agree */
549 nand_width
= au_readl(MEM_STCFG0
) & (1 << 22);
551 nand_width
= au_readl(MEM_STCFG1
) & (1 << 22);
553 nand_width
= au_readl(MEM_STCFG2
) & (1 << 22);
555 nand_width
= au_readl(MEM_STCFG3
) & (1 << 22);
557 /* Set address of hardware control function */
558 this->dev_ready
= au1550_device_ready
;
559 this->select_chip
= au1550_select_chip
;
560 this->cmdfunc
= au1550_command
;
562 /* 30 us command delay time */
563 this->chip_delay
= 30;
564 this->ecc
.mode
= NAND_ECC_SOFT
;
566 this->options
= NAND_NO_AUTOINCR
;
569 this->options
|= NAND_BUSWIDTH_16
;
571 this->read_byte
= (!nand_width
) ? au_read_byte16
: au_read_byte
;
572 au1550_write_byte
= (!nand_width
) ? au_write_byte16
: au_write_byte
;
573 this->read_word
= au_read_word
;
574 this->write_buf
= (!nand_width
) ? au_write_buf16
: au_write_buf
;
575 this->read_buf
= (!nand_width
) ? au_read_buf16
: au_read_buf
;
576 this->verify_buf
= (!nand_width
) ? au_verify_buf16
: au_verify_buf
;
578 /* Scan to find existence of the device */
579 if (nand_scan(au1550_mtd
, 1)) {
584 /* Register the partitions */
585 add_mtd_partitions(au1550_mtd
, partition_info
, ARRAY_SIZE(partition_info
));
590 iounmap((void *)p_nand
);
597 module_init(au1xxx_nand_init
);
602 static void __exit
au1550_cleanup(void)
604 /* Release resources, unregister device */
605 nand_release(au1550_mtd
);
607 /* Free the MTD device structure */
611 iounmap((void *)p_nand
);
614 module_exit(au1550_cleanup
);
616 MODULE_LICENSE("GPL");
617 MODULE_AUTHOR("Embedded Edge, LLC");
618 MODULE_DESCRIPTION("Board-specific glue layer for NAND flash on Pb1550 board");