2 * Copyright (C) 2003 Rick Bronson
4 * Derived from drivers/mtd/nand/autcpu12.c
5 * Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
7 * Derived from drivers/mtd/spia.c
8 * Copyright (C) 2000 Steven J. Hill (sjhill@cotw.com)
11 * Add Hardware ECC support for AT91SAM9260 / AT91SAM9263
12 * Richard Genoud (richard.genoud@gmail.com), Adeneo Copyright (C) 2007
14 * Derived from Das U-Boot source code
15 * (u-boot-1.1.5/board/atmel/at91sam9263ek/nand.c)
16 * (C) Copyright 2006 ATMEL Rousset, Lacressonniere Nicolas
19 * This program is free software; you can redistribute it and/or modify
20 * it under the terms of the GNU General Public License version 2 as
21 * published by the Free Software Foundation.
25 #include <linux/slab.h>
26 #include <linux/module.h>
27 #include <linux/platform_device.h>
28 #include <linux/mtd/mtd.h>
29 #include <linux/mtd/nand.h>
30 #include <linux/mtd/partitions.h>
32 #include <linux/gpio.h>
35 #include <mach/board.h>
38 #ifdef CONFIG_MTD_NAND_ATMEL_ECC_HW
44 #ifdef CONFIG_MTD_NAND_ATMEL_ECC_NONE
50 /* Register access macros */
51 #define ecc_readl(add, reg) \
52 __raw_readl(add + ATMEL_ECC_##reg)
53 #define ecc_writel(add, reg, value) \
54 __raw_writel((value), add + ATMEL_ECC_##reg)
56 #include "atmel_nand_ecc.h" /* Hardware ECC registers */
58 /* oob layout for large page size
59 * bad block info is on bytes 0 and 1
60 * the bytes have to be consecutives to avoid
61 * several NAND_CMD_RNDOUT during read
63 static struct nand_ecclayout atmel_oobinfo_large = {
65 .eccpos = {60, 61, 62, 63},
71 /* oob layout for small page size
72 * bad block info is on bytes 4 and 5
73 * the bytes have to be consecutives to avoid
74 * several NAND_CMD_RNDOUT during read
76 static struct nand_ecclayout atmel_oobinfo_small = {
78 .eccpos = {0, 1, 2, 3},
84 struct atmel_nand_host {
85 struct nand_chip nand_chip;
87 void __iomem *io_base;
88 struct atmel_nand_data *board;
96 static void atmel_nand_enable(struct atmel_nand_host *host)
98 if (host->board->enable_pin)
99 gpio_set_value(host->board->enable_pin, 0);
105 static void atmel_nand_disable(struct atmel_nand_host *host)
107 if (host->board->enable_pin)
108 gpio_set_value(host->board->enable_pin, 1);
112 * Hardware specific access to control-lines
114 static void atmel_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
116 struct nand_chip *nand_chip = mtd->priv;
117 struct atmel_nand_host *host = nand_chip->priv;
119 if (ctrl & NAND_CTRL_CHANGE) {
121 atmel_nand_enable(host);
123 atmel_nand_disable(host);
125 if (cmd == NAND_CMD_NONE)
129 writeb(cmd, host->io_base + (1 << host->board->cle));
131 writeb(cmd, host->io_base + (1 << host->board->ale));
135 * Read the Device Ready pin.
137 static int atmel_nand_device_ready(struct mtd_info *mtd)
139 struct nand_chip *nand_chip = mtd->priv;
140 struct atmel_nand_host *host = nand_chip->priv;
142 return gpio_get_value(host->board->rdy_pin);
146 * Minimal-overhead PIO for data access.
148 static void atmel_read_buf(struct mtd_info *mtd, u8 *buf, int len)
150 struct nand_chip *nand_chip = mtd->priv;
152 __raw_readsb(nand_chip->IO_ADDR_R, buf, len);
155 static void atmel_read_buf16(struct mtd_info *mtd, u8 *buf, int len)
157 struct nand_chip *nand_chip = mtd->priv;
159 __raw_readsw(nand_chip->IO_ADDR_R, buf, len / 2);
162 static void atmel_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
164 struct nand_chip *nand_chip = mtd->priv;
166 __raw_writesb(nand_chip->IO_ADDR_W, buf, len);
169 static void atmel_write_buf16(struct mtd_info *mtd, const u8 *buf, int len)
171 struct nand_chip *nand_chip = mtd->priv;
173 __raw_writesw(nand_chip->IO_ADDR_W, buf, len / 2);
177 * write oob for small pages
179 static int atmel_nand_write_oob_512(struct mtd_info *mtd,
180 struct nand_chip *chip, int page)
182 int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
183 int eccsize = chip->ecc.size, length = mtd->oobsize;
184 int len, pos, status = 0;
185 const uint8_t *bufpoi = chip->oob_poi;
187 pos = eccsize + chunk;
189 chip->cmdfunc(mtd, NAND_CMD_SEQIN, pos, page);
190 len = min_t(int, length, chunk);
191 chip->write_buf(mtd, bufpoi, len);
195 chip->write_buf(mtd, bufpoi, length);
197 chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
198 status = chip->waitfunc(mtd, chip);
200 return status & NAND_STATUS_FAIL ? -EIO : 0;
205 * read oob for small pages
207 static int atmel_nand_read_oob_512(struct mtd_info *mtd,
208 struct nand_chip *chip, int page, int sndcmd)
211 chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
214 chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
221 * function called after a write
223 * mtd: MTD block structure
224 * dat: raw data (unused)
225 * ecc_code: buffer for ECC
227 static int atmel_nand_calculate(struct mtd_info *mtd,
228 const u_char *dat, unsigned char *ecc_code)
230 struct nand_chip *nand_chip = mtd->priv;
231 struct atmel_nand_host *host = nand_chip->priv;
232 uint32_t *eccpos = nand_chip->ecc.layout->eccpos;
233 unsigned int ecc_value;
235 /* get the first 2 ECC bytes */
236 ecc_value = ecc_readl(host->ecc, PR);
238 ecc_code[eccpos[0]] = ecc_value & 0xFF;
239 ecc_code[eccpos[1]] = (ecc_value >> 8) & 0xFF;
241 /* get the last 2 ECC bytes */
242 ecc_value = ecc_readl(host->ecc, NPR) & ATMEL_ECC_NPARITY;
244 ecc_code[eccpos[2]] = ecc_value & 0xFF;
245 ecc_code[eccpos[3]] = (ecc_value >> 8) & 0xFF;
251 * HW ECC read page function
253 * mtd: mtd info structure
254 * chip: nand chip info structure
255 * buf: buffer to store read data
257 static int atmel_nand_read_page(struct mtd_info *mtd,
258 struct nand_chip *chip, uint8_t *buf)
260 int eccsize = chip->ecc.size;
261 int eccbytes = chip->ecc.bytes;
262 uint32_t *eccpos = chip->ecc.layout->eccpos;
264 uint8_t *oob = chip->oob_poi;
269 * Errata: ALE is incorrectly wired up to the ECC controller
270 * on the AP7000, so it will include the address cycles in the
273 * Workaround: Reset the parity registers before reading the
276 if (cpu_is_at32ap7000()) {
277 struct atmel_nand_host *host = chip->priv;
278 ecc_writel(host->ecc, CR, ATMEL_ECC_RST);
282 chip->read_buf(mtd, p, eccsize);
284 /* move to ECC position if needed */
285 if (eccpos[0] != 0) {
286 /* This only works on large pages
287 * because the ECC controller waits for
288 * NAND_CMD_RNDOUTSTART after the
290 * anyway, for small pages, the eccpos[0] == 0
292 chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
293 mtd->writesize + eccpos[0], -1);
296 /* the ECC controller needs to read the ECC just after the data */
297 ecc_pos = oob + eccpos[0];
298 chip->read_buf(mtd, ecc_pos, eccbytes);
300 /* check if there's an error */
301 stat = chip->ecc.correct(mtd, p, oob, NULL);
304 mtd->ecc_stats.failed++;
306 mtd->ecc_stats.corrected += stat;
308 /* get back to oob start (end of page) */
309 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
312 chip->read_buf(mtd, oob, mtd->oobsize);
320 * function called after a read
322 * mtd: MTD block structure
323 * dat: raw data read from the chip
324 * read_ecc: ECC from the chip (unused)
327 * Detect and correct a 1 bit error for a page
329 static int atmel_nand_correct(struct mtd_info *mtd, u_char *dat,
330 u_char *read_ecc, u_char *isnull)
332 struct nand_chip *nand_chip = mtd->priv;
333 struct atmel_nand_host *host = nand_chip->priv;
334 unsigned int ecc_status;
335 unsigned int ecc_word, ecc_bit;
337 /* get the status from the Status Register */
338 ecc_status = ecc_readl(host->ecc, SR);
340 /* if there's no error */
341 if (likely(!(ecc_status & ATMEL_ECC_RECERR)))
344 /* get error bit offset (4 bits) */
345 ecc_bit = ecc_readl(host->ecc, PR) & ATMEL_ECC_BITADDR;
346 /* get word address (12 bits) */
347 ecc_word = ecc_readl(host->ecc, PR) & ATMEL_ECC_WORDADDR;
350 /* if there are multiple errors */
351 if (ecc_status & ATMEL_ECC_MULERR) {
352 /* check if it is a freshly erased block
353 * (filled with 0xff) */
354 if ((ecc_bit == ATMEL_ECC_BITADDR)
355 && (ecc_word == (ATMEL_ECC_WORDADDR >> 4))) {
356 /* the block has just been erased, return OK */
359 /* it doesn't seems to be a freshly
361 * We can't correct so many errors */
362 dev_dbg(host->dev, "atmel_nand : multiple errors detected."
363 " Unable to correct.\n");
367 /* if there's a single bit error : we can correct it */
368 if (ecc_status & ATMEL_ECC_ECCERR) {
369 /* there's nothing much to do here.
370 * the bit error is on the ECC itself.
372 dev_dbg(host->dev, "atmel_nand : one bit error on ECC code."
373 " Nothing to correct\n");
377 dev_dbg(host->dev, "atmel_nand : one bit error on data."
378 " (word offset in the page :"
379 " 0x%x bit offset : 0x%x)\n",
381 /* correct the error */
382 if (nand_chip->options & NAND_BUSWIDTH_16) {
384 ((unsigned short *) dat)[ecc_word] ^= (1 << ecc_bit);
387 dat[ecc_word] ^= (1 << ecc_bit);
389 dev_dbg(host->dev, "atmel_nand : error corrected\n");
394 * Enable HW ECC : unused on most chips
396 static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
398 if (cpu_is_at32ap7000()) {
399 struct nand_chip *nand_chip = mtd->priv;
400 struct atmel_nand_host *host = nand_chip->priv;
401 ecc_writel(host->ecc, CR, ATMEL_ECC_RST);
405 #ifdef CONFIG_MTD_PARTITIONS
406 static const char *part_probes[] = { "cmdlinepart", NULL };
410 * Probe for the NAND device.
412 static int __init atmel_nand_probe(struct platform_device *pdev)
414 struct atmel_nand_host *host;
415 struct mtd_info *mtd;
416 struct nand_chip *nand_chip;
417 struct resource *regs;
418 struct resource *mem;
421 #ifdef CONFIG_MTD_PARTITIONS
422 struct mtd_partition *partitions = NULL;
423 int num_partitions = 0;
426 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
428 printk(KERN_ERR "atmel_nand: can't get I/O resource mem\n");
432 /* Allocate memory for the device structure (and zero it) */
433 host = kzalloc(sizeof(struct atmel_nand_host), GFP_KERNEL);
435 printk(KERN_ERR "atmel_nand: failed to allocate device structure.\n");
439 host->io_base = ioremap(mem->start, mem->end - mem->start + 1);
440 if (host->io_base == NULL) {
441 printk(KERN_ERR "atmel_nand: ioremap failed\n");
443 goto err_nand_ioremap;
447 nand_chip = &host->nand_chip;
448 host->board = pdev->dev.platform_data;
449 host->dev = &pdev->dev;
451 nand_chip->priv = host; /* link the private data structures */
452 mtd->priv = nand_chip;
453 mtd->owner = THIS_MODULE;
455 /* Set address of NAND IO lines */
456 nand_chip->IO_ADDR_R = host->io_base;
457 nand_chip->IO_ADDR_W = host->io_base;
458 nand_chip->cmd_ctrl = atmel_nand_cmd_ctrl;
460 if (host->board->rdy_pin)
461 nand_chip->dev_ready = atmel_nand_device_ready;
463 regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
464 if (!regs && hard_ecc) {
465 printk(KERN_ERR "atmel_nand: can't get I/O resource "
466 "regs\nFalling back on software ECC\n");
469 nand_chip->ecc.mode = NAND_ECC_SOFT; /* enable ECC */
471 nand_chip->ecc.mode = NAND_ECC_NONE;
472 if (hard_ecc && regs) {
473 host->ecc = ioremap(regs->start, regs->end - regs->start + 1);
474 if (host->ecc == NULL) {
475 printk(KERN_ERR "atmel_nand: ioremap failed\n");
477 goto err_ecc_ioremap;
479 nand_chip->ecc.mode = NAND_ECC_HW_SYNDROME;
480 nand_chip->ecc.calculate = atmel_nand_calculate;
481 nand_chip->ecc.correct = atmel_nand_correct;
482 nand_chip->ecc.hwctl = atmel_nand_hwctl;
483 nand_chip->ecc.read_page = atmel_nand_read_page;
484 nand_chip->ecc.bytes = 4;
485 nand_chip->ecc.prepad = 0;
486 nand_chip->ecc.postpad = 0;
489 nand_chip->chip_delay = 20; /* 20us command delay time */
491 if (host->board->bus_width_16) { /* 16-bit bus width */
492 nand_chip->options |= NAND_BUSWIDTH_16;
493 nand_chip->read_buf = atmel_read_buf16;
494 nand_chip->write_buf = atmel_write_buf16;
496 nand_chip->read_buf = atmel_read_buf;
497 nand_chip->write_buf = atmel_write_buf;
500 platform_set_drvdata(pdev, host);
501 atmel_nand_enable(host);
503 if (host->board->det_pin) {
504 if (gpio_get_value(host->board->det_pin)) {
505 printk("No SmartMedia card inserted.\n");
511 /* first scan to find the device and get the page size */
512 if (nand_scan_ident(mtd, 1)) {
517 if (nand_chip->ecc.mode == NAND_ECC_HW_SYNDROME) {
518 /* ECC is calculated for the whole page (1 step) */
519 nand_chip->ecc.size = mtd->writesize;
521 /* set ECC page size and oob layout */
522 switch (mtd->writesize) {
524 nand_chip->ecc.layout = &atmel_oobinfo_small;
525 nand_chip->ecc.read_oob = atmel_nand_read_oob_512;
526 nand_chip->ecc.write_oob = atmel_nand_write_oob_512;
527 ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_528);
530 nand_chip->ecc.layout = &atmel_oobinfo_large;
531 ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_1056);
534 nand_chip->ecc.layout = &atmel_oobinfo_large;
535 ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_2112);
538 nand_chip->ecc.layout = &atmel_oobinfo_large;
539 ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_4224);
542 /* page size not handled by HW ECC */
543 /* switching back to soft ECC */
544 nand_chip->ecc.mode = NAND_ECC_SOFT;
545 nand_chip->ecc.calculate = NULL;
546 nand_chip->ecc.correct = NULL;
547 nand_chip->ecc.hwctl = NULL;
548 nand_chip->ecc.read_page = NULL;
549 nand_chip->ecc.postpad = 0;
550 nand_chip->ecc.prepad = 0;
551 nand_chip->ecc.bytes = 0;
556 /* second phase scan */
557 if (nand_scan_tail(mtd)) {
562 #ifdef CONFIG_MTD_PARTITIONS
563 #ifdef CONFIG_MTD_CMDLINE_PARTS
564 mtd->name = "atmel_nand";
565 num_partitions = parse_mtd_partitions(mtd, part_probes,
568 if (num_partitions <= 0 && host->board->partition_info)
569 partitions = host->board->partition_info(mtd->size,
572 if ((!partitions) || (num_partitions == 0)) {
573 printk(KERN_ERR "atmel_nand: No parititions defined, or unsupported device.\n");
575 goto err_no_partitions;
578 res = add_mtd_partitions(mtd, partitions, num_partitions);
580 res = add_mtd_device(mtd);
586 #ifdef CONFIG_MTD_PARTITIONS
593 atmel_nand_disable(host);
594 platform_set_drvdata(pdev, NULL);
598 iounmap(host->io_base);
605 * Remove a NAND device.
607 static int __exit atmel_nand_remove(struct platform_device *pdev)
609 struct atmel_nand_host *host = platform_get_drvdata(pdev);
610 struct mtd_info *mtd = &host->mtd;
614 atmel_nand_disable(host);
618 iounmap(host->io_base);
624 static struct platform_driver atmel_nand_driver = {
625 .remove = __exit_p(atmel_nand_remove),
627 .name = "atmel_nand",
628 .owner = THIS_MODULE,
632 static int __init atmel_nand_init(void)
634 return platform_driver_probe(&atmel_nand_driver, atmel_nand_probe);
638 static void __exit atmel_nand_exit(void)
640 platform_driver_unregister(&atmel_nand_driver);
644 module_init(atmel_nand_init);
645 module_exit(atmel_nand_exit);
647 MODULE_LICENSE("GPL");
648 MODULE_AUTHOR("Rick Bronson");
649 MODULE_DESCRIPTION("NAND/SmartMedia driver for AT91 / AVR32");
650 MODULE_ALIAS("platform:atmel_nand");