@@ -319,6 +319,18 @@ config MTD_NAND_DISKONCHIP_BBTWRITE
load time (assuming you build diskonchip as a module) with the module
parameter "inftl_bbt_write=1".
+config MTD_NAND_DOCG4
+ tristate "Support for DiskOnChip G4 (EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ select BCH
+ select BITREVERSE
+ help
+ Support for diskonchip G4 nand flash, found in several smartphones,
+ such as the Palm Treo680 and HTC Prophet.
+
+ There is currently no support for the saftl filesystem; however a
+ ubifs has been succesfully tested on the device.
+
config MTD_NAND_SHARPSL
tristate "Support for NAND Flash on Sharp SL Series (C7xx + others)"
depends on ARCH_PXA
@@ -20,6 +20,7 @@ obj-$(CONFIG_MTD_NAND_PPCHAMELEONEVB) += ppchameleonevb.o
obj-$(CONFIG_MTD_NAND_S3C2410) += s3c2410.o
obj-$(CONFIG_MTD_NAND_DAVINCI) += davinci_nand.o
obj-$(CONFIG_MTD_NAND_DISKONCHIP) += diskonchip.o
+obj-$(CONFIG_MTD_NAND_DOCG4) += docg4.o
obj-$(CONFIG_MTD_NAND_FSMC) += fsmc_nand.o
obj-$(CONFIG_MTD_NAND_H1900) += h1910.o
obj-$(CONFIG_MTD_NAND_RTC_FROM4) += rtc_from4.o
new file mode 100644
@@ -0,0 +1,1220 @@
+/*
+ * drivers/mtd/nand/docg4.c
+ *
+ * Copyright (C) 2011 Mike Dunn <mikedunn@newsguy.com>
+ *
+ * mtd nand driver for M-Systems DiskOnChip G4 device
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ *
+ * TODO:
+ *
+ * Read factory bad block table (on page 4) during initialization and update
+ * the memory bbt accordingly.
+ *
+ * Implement power mgmt fns (suspend and resume)
+ *
+ * Support cmd-line partitions?
+ *
+ * Support raw reads / writes?
+ *
+ * Hamming ecc when reading oob only
+ *
+ * Support for multiple cascaded devices ("floors") ?
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/bitops.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/docg4.h>
+#include <linux/bch.h>
+#include <linux/bitrev.h>
+
+static int ignore_badblocks;
+module_param(ignore_badblocks, int, 0);
+MODULE_PARM_DESC(ignore_badblocks, "no badblock checking performed");
+
+struct docg4_priv {
+ struct mtd_info *mtd;
+ struct device *dev;
+ void __iomem *virtadr;
+ int status;
+ struct {
+ unsigned int command;
+ int column;
+ int page;
+ } last_command;
+ uint8_t oob_buf[16];
+ uint8_t ecc_buf[7];
+ int oob_page;
+ struct bch_control *bch;
+};
+
+/*
+ * Defines prefixed with DOCG4 are unique to the diskonchip G4.
+ * All others are shared with other diskonchip devices (e.g., P3, G3).
+ *
+ * Functions with names prefixed with docg4_ are mtd / nand interface functions
+ * (though they may also be called internally). All others are internal.
+ */
+
+#define DOC_IOSPACE_DATA 0x0800
+
+/* register offsets */
+#define DOC_CHIPID 0x1000
+#define DOC_DEVICESELECT 0x100a
+#define DOC_ASICMODE 0x100c
+#define DOC_DATAEND 0x101e
+#define DOC_NOP 0x103e
+
+#define DOC_FLASHSEQUENCE 0x1032
+#define DOC_FLASHCOMMAND 0x1034
+#define DOC_FLASHADDRESS 0x1036
+#define DOC_FLASHCONTROL 0x1038
+#define DOC_ECCCONF0 0x1040
+#define DOC_ECCCONF1 0x1042
+#define DOC_HAMMINGPARITY 0x1046
+#define DOC_BCH_SYNDROM(idx) (0x1048 + idx)
+
+#define DOC_ASICMODECONFIRM 0x1072
+#define DOC_CHIPID_INV 0x1074
+
+#define DOCG4_MYSTERY_REG 0x1050
+#define DOCG4_MYSTERY_REG_2 0x1052
+
+/* DOC_FLASHSEQUENCE register commands */
+#define DOC_SEQ_RESET 0x00
+#define DOC_SEQ_PAGE_SIZE_532 0x03
+#define DOCG4_SEQ_FLUSH 0x29
+#define DOCG4_SEQ_PAGEWRITE 0x16
+#define DOCG4_SEQ_PAGEPROG 0x1e
+#define DOCG4_SEQ_BLOCKERASE 0x24
+
+/* DOC_FLASHCOMMAND register commands */
+#define DOC_CMD_READ_PLANE1 0x00
+#define DOC_CMD_ERASECYCLE2 0xd0
+#define DOC_CMD_READ_STATUS 0x70
+#define DOC_CMD_READ_ALL_PLANES 0x30
+#define DOC_CMD_PROG_BLOCK_ADDR 0x60
+#define DOC_CMD_PROG_CYCLE1 0x80
+#define DOC_CMD_PROG_CYCLE2 0x10
+#define DOC_CMD_RESET 0xff
+
+/* DOC_FLASHCONTROL register bits */
+#define DOC_CTRL_CE 0x10
+#define DOC_CTRL_UNKNOWN 0x40
+#define DOC_CTRL_FLASHREADY 0x01
+
+/* DOC_ECCCONF0 register bits */
+#define DOC_ECCCONF0_READ_MODE 0x8000
+#define DOC_ECCCONF0_AUTO_ECC_ENABLE 0x4000
+#define DOC_ECCCONF0_HAMMING_ENABLE 0x1000
+#define DOC_ECCCONF0_UNKNOWN 0x2000
+#define DOC_ECCCONF0_DATA_BYTES_MASK 0x07ff
+
+/* DOC_ECCCONF1 register bits */
+#define DOC_ECCCONF1_BCH_SYNDROM_ERR 0x80
+#define DOC_ECCCONF1_ECC_ENABLE 0x07
+
+/* DOC_ASICMODE register bits */
+#define DOCG4_RESET 0x04 /* TODO: these two should apply... */
+#define DOCG4_NORMAL 0x05 /* ...to the G3 as well */
+
+/* good status values read after read/write/erase operations */
+#define DOCG4_PROGSTATUS_GOOD 0x51
+#define DOCG4_PROGSTATUS_GOOD_2 0xe0
+
+/*
+ * On read operations (page and oob-only), the first byte read from I/O reg is a
+ * status. On error, it reads 0x73; otherwise, it reads either 0x71 (first read
+ * after reset only) or 0x51, so bit 1 is presumed to be an error indicator.
+ */
+#define DOCG4_READ_ERROR 0x02 /* bit 1 indicates read error */
+
+/* anatomy of the device */
+#define DOCG4_CHIP_SIZE 0x8000000
+#define DOCG4_PAGE_SIZE 0x200
+#define DOCG4_PAGES_PER_BLOCK 0x200
+#define DOCG4_BLOCK_SIZE (DOCG4_PAGES_PER_BLOCK * DOCG4_PAGE_SIZE)
+#define DOCG4_NUMBLOCKS (DOCG4_CHIP_SIZE / DOCG4_BLOCK_SIZE)
+#define DOCG4_OOB_SIZE 0x10
+#define DOCG4_CHIP_SHIFT 27 /* log_2(DOCG4_CHIP_SIZE) */
+#define DOCG4_PAGE_SHIFT 9 /* log_2(DOCG4_PAGE_SIZE) */
+#define DOCG4_ERASE_SHIFT 18 /* log_2(DOCG4_BLOCK_SIZE) */
+
+/* all but the last byte is included in ecc calculation */
+#define DOCG4_BCH_SIZE (DOCG4_PAGE_SIZE + DOCG4_OOB_SIZE - 1)
+
+#define DOCG4_USERDATA_LEN 520 /* 512 byte page plus 8 oob avail to user */
+
+/* expected values from the ID registers */
+#define DOCG4_IDREG1_VALUE 0x0400
+#define DOCG4_IDREG2_VALUE 0xfbff
+
+/* primitive polynomial used to build the Galois field used by hw ecc gen */
+#define DOCG4_PRIMITIVE_POLY 0x4443
+
+#define DOCG4_M 14 /* Galois field is of order 2^14 */
+#define DOCG4_T 4 /* BCH alg corrects up to 4 bit errors */
+
+
+/* value generated by the HW ecc generator upon reading blank page */
+static uint8_t blank_read_hwecc[7] = {
+ 0xcf, 0x72, 0xfc, 0x1b, 0xa9, 0xc7, 0xb9 };
+
+/*
+ * Oob bytes 0 - 6 are available to the user.
+ * Byte 7 is hamming ecc for first 7 bytes. Bytes 8 - 14 are hw-generated ecc.
+ * Byte 15 (the last) is used by the driver as a "page programmed" flag.
+ */
+static struct nand_ecclayout docg4_oobinfo = {
+ .eccbytes = 9,
+ .eccpos = {7, 8, 9, 10, 11, 12, 13, 14, 15},
+ .oobavail = 7,
+ .oobfree = { {0, 7} }
+};
+
+/* the device has a nop register used to insert precise delays */
+static inline void doc_nop(void __iomem *docptr)
+{
+ writew(0, docptr + DOC_NOP);
+}
+
+static void docg4_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+ int i;
+ struct nand_chip *nand = mtd->priv;
+ uint16_t *p = (uint16_t *) buf;
+ len >>= 1;
+
+ for (i = 0; i < len; i++)
+ p[i] = readw(nand->IO_ADDR_R);
+}
+
+static void docg4_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+ int i;
+ struct nand_chip *nand = mtd->priv;
+ uint16_t *p = (uint16_t *) buf;
+ len >>= 1;
+
+ for (i = 0; i < len; i++)
+ writew(p[i], nand->IO_ADDR_W);
+}
+
+static int docg4_wait(struct mtd_info *mtd, struct nand_chip *nand)
+{
+ /* polls the doc status register waiting for device ready */
+
+ uint16_t flash_status;
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+ unsigned long timeo = jiffies + (HZ * 10);
+
+ dev_dbg(doc->dev, "%s...\n", __func__);
+
+ /* report any previously unreported error */
+ if (doc->status) {
+ int stat = doc->status;
+ doc->status = 0;
+ return stat;
+ }
+
+ /* hardware quirk of g4 requires reading twice initially */
+ flash_status = readw(docptr + DOC_FLASHCONTROL);
+ flash_status = readw(docptr + DOC_FLASHCONTROL);
+
+ while (!(flash_status & DOC_CTRL_FLASHREADY)) {
+ if (time_after(jiffies, timeo)) {
+ dev_err(doc->dev, "docg4_wait timed out\n");
+ return NAND_STATUS_FAIL;
+ }
+ cpu_relax();
+ flash_status = readb(docptr + DOC_FLASHCONTROL);
+ }
+
+ return NAND_STATUS_READY;
+}
+
+static void docg4_select_chip(struct mtd_info *mtd, int chip)
+{
+ /*
+ * Select among multiple cascaded chips ("floors"). Multiple floors are
+ * not yet supported, so the only valid positive value is 0.
+ */
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+
+ dev_dbg(doc->dev, "%s: chip %d\n", __func__, chip);
+
+ if (chip < 0)
+ return; /* deselected */
+
+ if (chip > 0)
+ dev_warn(doc->dev, "multiple floors currently unsupported\n");
+
+ writew(0, docptr + DOC_DEVICESELECT);
+}
+
+static void reset(struct mtd_info *mtd, struct nand_chip *nand)
+{
+ /* full device reset */
+
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+
+ writew(DOCG4_RESET, docptr + DOC_ASICMODE);
+ writew(~DOCG4_RESET, docptr + DOC_ASICMODECONFIRM);
+ doc_nop(docptr);
+ writew(DOCG4_NORMAL, docptr + DOC_ASICMODE);
+ writew(~DOCG4_NORMAL, docptr + DOC_ASICMODECONFIRM);
+
+ writew(DOC_ECCCONF1_ECC_ENABLE, docptr + DOC_ECCCONF1);
+
+ docg4_wait(mtd, nand);
+}
+
+static void read_hw_ecc(void __iomem *docptr, uint8_t *ecc_buf)
+{
+ /* read the 7 hw-generated ecc bytes */
+
+ int i;
+ for (i = 0; i < 7; i++) { /* hw quirk; read twice */
+ ecc_buf[i] = readb(docptr + DOC_BCH_SYNDROM(i));
+ ecc_buf[i] = readb(docptr + DOC_BCH_SYNDROM(i));
+ }
+}
+
+static int correct_data(struct mtd_info *mtd, uint8_t *buf, int page)
+{
+ /*
+ * Called after a page read to check for bit errors, and correct them if
+ * so. Up to four bits can be corrected.
+ */
+
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+ uint16_t edc_err;
+ int i, numerrs, errpos[4];
+
+ /* read the register that tells us if a read error was detected */
+ edc_err = readw(docptr + DOC_ECCCONF1);
+ edc_err = readw(docptr + DOC_ECCCONF1); /* hw quirk: read twice */
+
+ dev_dbg(doc->dev, "%s: edc_err = 0x%02x\n", __func__, edc_err);
+
+ if (!(edc_err & DOC_ECCCONF1_BCH_SYNDROM_ERR))
+ return 0; /* no error bits */
+
+ /* data contains error(s); read the 7 hw-generated ecc bytes */
+ read_hw_ecc(docptr, doc->ecc_buf);
+
+ /* check if ecc bytes are those of a blank page */
+ if (!memcmp(doc->ecc_buf, blank_read_hwecc, 7))
+ return 0; /* blank page; ecc error normal */
+
+ /*
+ * If the hw ecc bytes are not those of a blank page, there's still a
+ * chance that the page is blank, but was read with errors. Check the
+ * programmed flag in last oob byte, which is set to zero when a page is
+ * programmed. If more than half the bits are set, assume a blank
+ * page. Unfortunately, the read error(s) are not reported in stats.
+ */
+ if (doc->oob_buf[15]) {
+ int bit, numsetbits = 0;
+ unsigned long programmed_flag = doc->oob_buf[15];
+ for_each_set_bit(bit, &programmed_flag, 8)
+ numsetbits++;
+ if (numsetbits > 4) { /* assume blank page */
+ dev_warn(doc->dev,
+ "error(s) in blank page at offset %08x\n",
+ page * DOCG4_PAGE_SIZE);
+ memset(buf, 0xff, DOCG4_PAGE_SIZE);
+ memset(doc->oob_buf, 0xff, DOCG4_OOB_SIZE);
+ return 0;
+ }
+ }
+
+ /*
+ * The hardware ecc unit produces oob_ecc ^ calc_ecc. The kernel's bch
+ * algorithm is used to decode this. However the hw operates on page
+ * data in a bit order that is the reverse of that of the bch alg,
+ * requiring that the bits be reversed on the result. Thanks to Ivan
+ * Djelic for his analysis!
+ */
+ for (i = 0; i < 7; i++)
+ doc->ecc_buf[i] = bitrev8(doc->ecc_buf[i]);
+
+ numerrs = decode_bch(doc->bch, NULL, DOCG4_USERDATA_LEN, NULL,
+ doc->ecc_buf, NULL, errpos);
+
+ if (numerrs == -EBADMSG) {
+ dev_warn(doc->dev, "uncorrectable errors at offset %08x\n",
+ page * DOCG4_PAGE_SIZE);
+ return -1;
+ }
+
+ BUG_ON(numerrs < 0); /* -EINVAL, or anything other than -EBADMSG */
+
+ /* undo last step in BCH alg (modulo mirroring not needed) */
+ for (i = 0; i < numerrs; i++)
+ errpos[i] = (errpos[i] & ~7)|(7-(errpos[i] & 7));
+
+ /* fix the errors */
+ for (i = 0; i < numerrs; i++) {
+
+ /* ignore if error within oob ecc bytes */
+ if (errpos[i] > DOCG4_USERDATA_LEN * 8)
+ continue;
+
+ /* if error within oob area preceeding ecc bytes */
+ if (errpos[i] > DOCG4_PAGE_SIZE * 8)
+ change_bit(errpos[i] - DOCG4_PAGE_SIZE * 8,
+ (unsigned long *)doc->oob_buf);
+
+ else /* error in page data */
+ change_bit(errpos[i], (unsigned long *)buf);
+ }
+
+ dev_notice(doc->dev, "%d error(s) corrected at offset %08x\n",
+ numerrs, page * DOCG4_PAGE_SIZE);
+
+ return numerrs;
+}
+
+static uint8_t docg4_read_byte(struct mtd_info *mtd)
+{
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+
+ dev_dbg(doc->dev, "%s\n", __func__);
+
+ if (doc->last_command.command == NAND_CMD_STATUS) {
+ int status;
+
+ /*
+ * Previous nand command was status request, so nand
+ * infrastructure code expects to read the status here. If an
+ * error occurred in a previous operation, report it.
+ */
+ doc->last_command.command = 0;
+
+ if (doc->status) {
+ status = doc->status;
+ doc->status = 0;
+ }
+
+ /* why is NAND_STATUS_WP inverse logic?? */
+ else
+ status = NAND_STATUS_WP | NAND_STATUS_READY;
+
+ return status;
+ }
+
+ dev_warn(doc->dev, "unexpectd call to read_byte()\n");
+
+ return 0;
+}
+
+static void write_addr(struct docg4_priv *doc, uint32_t docg4_addr)
+{
+ /* write the four address bytes packed in docg4_addr to the device */
+
+ void __iomem *docptr = doc->virtadr;
+ writeb(docg4_addr & 0xff, docptr + DOC_FLASHADDRESS);
+ docg4_addr >>= 8;
+ writeb(docg4_addr & 0xff, docptr + DOC_FLASHADDRESS);
+ docg4_addr >>= 8;
+ writeb(docg4_addr & 0xff, docptr + DOC_FLASHADDRESS);
+ docg4_addr >>= 8;
+ writeb(docg4_addr & 0xff, docptr + DOC_FLASHADDRESS);
+}
+
+static int read_progstatus(struct docg4_priv *doc)
+{
+ /*
+ * This apparently checks the status of programming.
+ * Called after an erasure, and after page data is written.
+ */
+ void __iomem *docptr = doc->virtadr;
+
+ /* status is read from the I/O reg */
+ uint16_t status1 = readw(docptr + DOC_IOSPACE_DATA);
+ uint16_t status2 = readw(docptr + DOC_IOSPACE_DATA);
+ uint16_t status3 = readw(docptr + DOCG4_MYSTERY_REG);
+
+ dev_dbg(doc->dev, "docg4: %s: %02x %02x %02x\n",
+ __func__, status1, status2, status3);
+
+ if (status1 != DOCG4_PROGSTATUS_GOOD
+ || status2 != DOCG4_PROGSTATUS_GOOD_2
+ || status3 != DOCG4_PROGSTATUS_GOOD_2) {
+ doc->status = NAND_STATUS_FAIL;
+ dev_warn(doc->dev, "read_progstatus failed: "
+ "%02x, %02x, %02x\n", status1, status2, status3);
+ return -EIO;
+ }
+ return 0;
+}
+
+static int pageprog(struct mtd_info *mtd)
+{
+ /*
+ * Final step in writing a page. Writes the contents of its
+ * internal buffer out the flash array, or some such.
+ */
+
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+ int retval = 0;
+
+ dev_dbg(doc->dev, "docg4: %s\n", __func__);
+
+ writew(DOCG4_SEQ_PAGEPROG, docptr + DOC_FLASHSEQUENCE);
+ writew(DOC_CMD_PROG_CYCLE2, docptr + DOC_FLASHCOMMAND);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ docg4_wait(mtd, nand);
+ writew(DOCG4_SEQ_FLUSH, docptr + DOC_FLASHSEQUENCE);
+ writew(DOC_CMD_READ_STATUS, docptr + DOC_FLASHCOMMAND);
+ writew(DOC_ECCCONF0_READ_MODE | 4, docptr + DOC_ECCCONF0);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ retval = read_progstatus(doc); /* read status from device */
+ writew(0, docptr + DOC_DATAEND);
+ doc_nop(docptr);
+ docg4_wait(mtd, nand);
+ doc_nop(docptr);
+
+ return retval;
+}
+
+static void sequence_reset(struct mtd_info *mtd)
+{
+ /* common starting sequence for all operations */
+
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+
+ writew(DOC_CTRL_UNKNOWN | DOC_CTRL_CE, docptr + DOC_FLASHCONTROL);
+ writew(DOC_SEQ_RESET, docptr + DOC_FLASHSEQUENCE);
+ writew(DOC_CMD_RESET, docptr + DOC_FLASHCOMMAND);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ docg4_wait(mtd, nand);
+ doc_nop(docptr);
+}
+
+static void read_page_prologue(struct mtd_info *mtd, uint32_t docg4_addr)
+{
+ /* first step in reading a page */
+
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+
+ dev_dbg(doc->dev,
+ "docg4: %s: g4 page %08x\n", __func__, docg4_addr);
+
+ sequence_reset(mtd);
+
+ writew(DOC_SEQ_PAGE_SIZE_532, docptr + DOC_FLASHSEQUENCE);
+ writew(DOC_CMD_READ_PLANE1, docptr + DOC_FLASHCOMMAND);
+ doc_nop(docptr);
+
+ write_addr(doc, docg4_addr);
+
+ doc_nop(docptr);
+ writew(DOC_CMD_READ_ALL_PLANES, docptr + DOC_FLASHCOMMAND);
+ doc_nop(docptr);
+ doc_nop(docptr);
+
+ docg4_wait(mtd, nand);
+}
+
+static void write_page_prologue(struct mtd_info *mtd, uint32_t docg4_addr)
+{
+ /* first step in writing a page */
+
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+
+ dev_dbg(doc->dev,
+ "docg4: %s: g4 addr: %x\n", __func__, docg4_addr);
+ sequence_reset(mtd);
+ writew(DOCG4_SEQ_PAGEWRITE, docptr + DOC_FLASHSEQUENCE);
+ writew(DOC_CMD_PROG_CYCLE1, docptr + DOC_FLASHCOMMAND);
+ doc_nop(docptr);
+ write_addr(doc, docg4_addr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ docg4_wait(mtd, nand);
+}
+
+static uint32_t mtd_to_docg4_address(int page, int column)
+{
+ /*
+ * Convert mtd address to format used by the device, 32 bit packed.
+ *
+ * Some notes on G4 addressing... The M-Sys documentation on this device
+ * claims that pages are 2K in length, and indeed, the format of the
+ * address used by the device reflects that. But within each page are
+ * four 512 byte "sub-pages", each with its own oob data that is
+ * read/written immediately after the 512 bytes of page data. This oob
+ * data contains the ecc bytes for the preceeding 512 bytes.
+ *
+ * Rather than tell the mtd nand infrastructure that page size is 2k,
+ * with four sub-pages each, we engage in a little subterfuge and tell
+ * the infrastructure code that pages are 512 bytes in size. This is
+ * done because during the course of reverse-engineering the device, I
+ * never observed an instance where an entire 2K "page" was read or
+ * written as a unit. Each "sub-page" is always addressed individually,
+ * its data read/written, and ecc handled before the next "sub-page" is
+ * addressed. Also, MLC nand devices are reported to not have
+ * sub-pages, so they're probably not sub-pages in the mtd sense.
+ *
+ * This requires us to convert addresses passed by the mtd nand
+ * infrastructure code to those used by the device.
+ *
+ * The address that is written to the device consists of four bytes: the
+ * first two are the 2k page number, and the second is the index into
+ * the page. The index is in terms of 16-bit half-words and includes
+ * the preceeding oob data, so e.g., the index into the second
+ * "sub-page" is 0x108, and the full device address of the start of mtd
+ * page 0x201 is 0x00800108. Note that the only valid index values are
+ * those for the start of a 512-byte page, or the start of the oob for
+ * one of those pages (oob-only reads).
+ */
+ int g4_page = page / 4; /* device's 2K page */
+ int g4_index = (page % 4) * 0x108 + column/2; /* offset into page */
+ return (g4_page << 16) | g4_index;
+}
+
+static void docg4_command(struct mtd_info *mtd, unsigned command, int column,
+ int page_addr)
+{
+ /* handle standard nand commands */
+
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+ uint32_t g4_addr = mtd_to_docg4_address(page_addr, column);
+
+ dev_dbg(doc->dev, "%s %x, page_addr=%x, column=%x\n",
+ __func__, command, page_addr, column);
+
+ /*
+ * Save the command and its arguments. This enables emulation of
+ * standard flash devices, and also some optimizations.
+ */
+ doc->last_command.command = command;
+ doc->last_command.column = column;
+ doc->last_command.page = page_addr;
+
+ switch (command) {
+
+ case NAND_CMD_RESET:
+ reset(mtd, nand);
+ break;
+
+ case NAND_CMD_READ0:
+ read_page_prologue(mtd, g4_addr);
+ break;
+
+ case NAND_CMD_STATUS:
+ /* next call to read_byte() will expect a status */
+ break;
+
+ case NAND_CMD_SEQIN:
+ write_page_prologue(mtd, g4_addr);
+
+ /* hack for deferred write of oob bytes */
+ if (doc->oob_page == page_addr)
+ memcpy(nand->oob_poi, doc->oob_buf, 16);
+ break;
+
+ case NAND_CMD_PAGEPROG:
+ pageprog(mtd);
+ break;
+
+ /* we don't expect these, based on review of nand_base.c */
+ case NAND_CMD_READOOB:
+ case NAND_CMD_READID:
+ case NAND_CMD_ERASE1:
+ case NAND_CMD_ERASE2:
+ dev_warn(doc->dev, "docg4_command: "
+ "unexpected command 0x%x\n", command);
+ break;
+
+ }
+}
+
+static int docg4_read_page_raw(struct mtd_info *mtd, struct nand_chip *nand,
+ uint8_t *buf, int page)
+{
+ /* TODO: support raw read? */
+ return -ENOTSUPP;
+}
+
+static int docg4_read_page(struct mtd_info *mtd, struct nand_chip *nand,
+ uint8_t *buf, int page)
+{
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+ uint16_t status, *buf16;
+ int bits_corrected;
+
+ dev_dbg(doc->dev, "%s: page %08x\n", __func__, page);
+
+ writew(DOC_ECCCONF0_READ_MODE |
+ DOC_ECCCONF0_HAMMING_ENABLE |
+ DOC_ECCCONF0_UNKNOWN |
+ DOCG4_BCH_SIZE,
+ docptr + DOC_ECCCONF0);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+
+ /* the 1st byte from the I/O reg is a status; the rest is page data */
+ status = readw(docptr + DOC_IOSPACE_DATA);
+ if (status & DOCG4_READ_ERROR) {
+ dev_err(doc->dev,
+ "docg4_read_page: bad status: 0x%02x\n", status);
+ doc->status = NAND_STATUS_FAIL;
+ return -EIO;
+ }
+
+ dev_dbg(doc->dev, "%s: status = 0x%x\n", __func__, status);
+
+ docg4_read_buf(mtd, buf, DOCG4_PAGE_SIZE); /* read the page data */
+
+ /*
+ * Diskonchips read oob immediately after a page read. Mtd
+ * infrastructure issues a separate command for reading oob after the
+ * page is read. So we save the oob bytes in a local buffer and just
+ * copy it when the command for reading oob arrives.
+ */
+
+ /* first 14 oob bytes read from I/O reg */
+ docg4_read_buf(mtd, doc->oob_buf, 14);
+
+ /* last 2 read from another reg */
+ buf16 = (uint16_t *)(doc->oob_buf + 14);
+ *buf16 = readw(docptr + DOCG4_MYSTERY_REG);
+
+ doc_nop(docptr);
+
+ bits_corrected = correct_data(mtd, buf, page);
+ if (bits_corrected < 0)
+ mtd->ecc_stats.failed++;
+ else
+ mtd->ecc_stats.corrected += bits_corrected;
+
+ writew(0, docptr + DOC_DATAEND);
+
+ return 0;
+}
+
+static int docg4_read_oob(struct mtd_info *mtd, struct nand_chip *nand,
+ int page, int sndcmd)
+{
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+ uint16_t status;
+
+ dev_dbg(doc->dev, "%s: page %x\n", __func__, page);
+
+ /*
+ * Oob bytes are read as part of a normal page read. If the last nand
+ * command was a read of the page whose oob is now being read, just copy
+ * the oob bytes that we saved in a local buffer and avoid a separate
+ * oob read.
+ */
+ if (doc->last_command.command == NAND_CMD_READ0 &&
+ doc->last_command.page == page) {
+ memcpy(nand->oob_poi, doc->oob_buf, 16);
+ return 0;
+ }
+
+ /*
+ * Separate read of oob data only.
+ */
+ docg4_command(mtd, NAND_CMD_READ0, nand->ecc.size, page);
+
+ writew(DOC_ECCCONF0_READ_MODE | DOCG4_OOB_SIZE, docptr + DOC_ECCCONF0);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+
+ /* the 1st byte from the I/O reg is a status; the rest is oob data */
+ status = readw(docptr + DOC_IOSPACE_DATA);
+ if (status & DOCG4_READ_ERROR) {
+ doc->status = NAND_STATUS_FAIL;
+ dev_warn(doc->dev,
+ "docg4_read_oob failed: status = 0x%02x\n", status);
+ return -EIO;
+ }
+
+ dev_dbg(doc->dev, "%s: status = 0x%x\n", __func__, status);
+
+ docg4_read_buf(mtd, nand->oob_poi, 16);
+
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ writew(0, docptr + DOC_DATAEND);
+ doc_nop(docptr);
+
+ return 0;
+}
+
+static void docg4_erase_block(struct mtd_info *mtd, int page)
+{
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+ uint16_t g4_page;
+
+ dev_dbg(doc->dev, "%s: page %04x\n", __func__, page);
+
+ sequence_reset(mtd);
+
+ writew(DOCG4_SEQ_BLOCKERASE, docptr + DOC_FLASHSEQUENCE);
+ writew(DOC_CMD_PROG_BLOCK_ADDR, docptr + DOC_FLASHCOMMAND);
+ doc_nop(docptr);
+
+ /* only 2 bytes of address are written to specify erase block */
+ g4_page = (uint16_t)(page / 4); /* to g4's 2k page addressing */
+ writeb(g4_page & 0xff, docptr + DOC_FLASHADDRESS);
+ g4_page >>= 8;
+ writeb(g4_page & 0xff, docptr + DOC_FLASHADDRESS);
+ doc_nop(docptr);
+
+ /* start the erasure */
+ writew(DOC_CMD_ERASECYCLE2, docptr + DOC_FLASHCOMMAND);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ docg4_wait(mtd, nand); /* long wait for erasure */
+
+ writew(DOCG4_SEQ_FLUSH, docptr + DOC_FLASHSEQUENCE);
+ writew(DOC_CMD_READ_STATUS, docptr + DOC_FLASHCOMMAND);
+ writew(DOC_ECCCONF0_READ_MODE | 4, docptr + DOC_ECCCONF0);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+ doc_nop(docptr);
+
+ read_progstatus(doc);
+
+ writew(0, docptr + DOC_DATAEND);
+ doc_nop(docptr);
+ docg4_wait(mtd, nand);
+ doc_nop(docptr);
+}
+
+static void docg4_write_page_raw(struct mtd_info *mtd, struct nand_chip *nand,
+ const uint8_t *buf)
+{
+ /* TODO: support raw write? */
+}
+
+static void docg4_write_page(struct mtd_info *mtd, struct nand_chip *nand,
+ const uint8_t *buf)
+{
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+ uint8_t hamming;
+ uint8_t ecc_buf[8];
+
+ dev_dbg(doc->dev, "%s...\n", __func__);
+
+ writew(DOC_ECCCONF0_HAMMING_ENABLE |
+ DOC_ECCCONF0_UNKNOWN |
+ DOCG4_BCH_SIZE,
+ docptr + DOC_ECCCONF0);
+ doc_nop(docptr);
+
+ /* write the page data */
+ docg4_write_buf16(mtd, buf, DOCG4_PAGE_SIZE);
+
+ /* oob bytes 0 through 5 are written to I/O reg */
+ docg4_write_buf16(mtd, nand->oob_poi, 6);
+
+ /* oob byte 6 written to a separate reg */
+ writew(nand->oob_poi[6], docptr + DOCG4_MYSTERY_REG_2);
+
+ doc_nop(docptr);
+ doc_nop(docptr);
+
+ /* oob byte 7 is hamming code */
+ hamming = readb(docptr + DOC_HAMMINGPARITY);
+ hamming = readb(docptr + DOC_HAMMINGPARITY); /* gotta read twice */
+ writew(hamming, docptr + DOCG4_MYSTERY_REG_2);
+ doc_nop(docptr);
+
+ /* read the 7 bytes from ecc regs and write to next oob area */
+ read_hw_ecc(docptr, ecc_buf);
+ ecc_buf[7] = 0; /* clear the "page programmed" byte */
+ docg4_write_buf16(mtd, ecc_buf, 8);
+
+ doc_nop(docptr);
+ doc_nop(docptr);
+ writew(0, docptr + DOC_DATAEND);
+ doc_nop(docptr);
+}
+
+static int docg4_write_oob(struct mtd_info *mtd, struct nand_chip *nand,
+ int page)
+{
+ /*
+ * This is not really supported, because MLC nand must write oob bytes
+ * at the same time as page data. Nonetheless, we save the oob buffer
+ * contents here, and then write it along with the page data if the same
+ * page is subsequently written. This allows user space utilities that
+ * write the oob data prior to the page data to work (e.g., nandwrite).
+ * The disdvantage is that, if the intention was to write oob only, the
+ * operation is quietly ignored. As the nand infrastructure code is
+ * currently written, this scenario has been carefully avoided.
+ */
+
+ /* note that bytes 7..14 are hw generated hamming/ecc and overwritten */
+ struct docg4_priv *doc = nand->priv;
+ doc->oob_page = page;
+ memcpy(doc->oob_buf, nand->oob_poi, 16);
+ return 0;
+}
+
+static int __init read_factory_bbt(struct mtd_info *mtd)
+{
+ /*
+ * The device contains a factory bad block table on page 4, but the
+ * table is not updated by this driver. Instead, this function is
+ * called during initialization to read it and update the memory-based
+ * bbt accordingly.
+ */
+
+ /* TODO: figure out how to interpret the table; mine is all ff's */
+ return 0;
+}
+
+static int docg4_block_markbad(struct mtd_info *mtd, loff_t ofs)
+{
+ /*
+ * Bad blocks are marked in the oob area of the first page of the block.
+ * The default scan_bbt() in the nand infrastructure code works fine for
+ * building the memory-based bbt during initialization. Likewise, the
+ * nand infrastructure function that checks if a block is bad works when
+ * a memory-based bbt is used. This function for marking a block as bad
+ * must replace the nand default because this device does not support
+ * writing only to the oob area (whole page must be written along with
+ * oob).
+ */
+ int ret, i;
+ uint8_t *buf;
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+ struct nand_bbt_descr *bbtd = nand->badblock_pattern;
+ int block = (int)(ofs >> nand->bbt_erase_shift);
+ int page = (int)(ofs >> nand->page_shift);
+ uint32_t g4_addr = mtd_to_docg4_address(page, 0);
+
+ dev_dbg(doc->dev, "%s: %08llx\n", __func__, ofs);
+
+ buf = kzalloc(DOCG4_PAGE_SIZE, GFP_KERNEL);
+ if (buf == NULL)
+ return -ENOMEM;
+
+ /* update bbt in memory */
+ nand->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);
+
+ /* write bit-wise negation of pattern to oob buffer */
+ memset(nand->oob_poi, 0xff, mtd->oobsize);
+ for (i = 0; i < bbtd->len; i++)
+ nand->oob_poi[bbtd->offs + i] = ~bbtd->pattern[i];
+
+ /* write first page of block */
+ write_page_prologue(mtd, g4_addr);
+ docg4_write_page(mtd, nand, buf);
+ ret = pageprog(mtd);
+ if (!ret)
+ mtd->ecc_stats.badblocks++;
+
+ kfree(buf);
+
+ return ret;
+}
+
+static int docg4_block_neverbad(struct mtd_info *mtd, loff_t ofs, int getchip)
+{
+ /* only called when ignore_badblocks option is set */
+ return 0;
+}
+
+static void __init init_mtd_structs(struct mtd_info *mtd)
+{
+ /* initialize mtd and nand data structures */
+
+ /*
+ * Note that some of the following initializations are not usually
+ * required within a nand driver because they are performed by the nand
+ * infrastructure code as part of nand_scan(). In this case they need
+ * to be initialized here because we skip call to nand_scan_ident() (the
+ * first half of nand_scan()). The call to nand_scan_ident() is skipped
+ * because for this device the chip id is not read in the manner of a
+ * standard nand device. Unfortunately, nand_scan_ident() does other
+ * things as well, such as call nand_set_defaults().
+ */
+
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+
+ mtd->size = DOCG4_CHIP_SIZE;
+ mtd->name = "Msys Diskonchip G4";
+ mtd->writesize = DOCG4_PAGE_SIZE;
+ mtd->erasesize = DOCG4_BLOCK_SIZE;
+ mtd->oobsize = DOCG4_OOB_SIZE;
+ nand->chipsize = DOCG4_CHIP_SIZE;
+ nand->chip_shift = DOCG4_CHIP_SHIFT;
+ nand->bbt_erase_shift = nand->phys_erase_shift = DOCG4_ERASE_SHIFT;
+ nand->chip_delay = 20;
+ nand->page_shift = DOCG4_PAGE_SHIFT;
+ nand->pagemask = 0x3ffff;
+ nand->badblockpos = NAND_LARGE_BADBLOCK_POS;
+ nand->badblockbits = 8;
+ nand->ecc.layout = &docg4_oobinfo;
+ nand->ecc.mode = NAND_ECC_HW_SYNDROME;
+ nand->ecc.size = DOCG4_PAGE_SIZE;
+ nand->ecc.prepad = 8;
+ nand->ecc.bytes = 8;
+ nand->options =
+ NAND_BUSWIDTH_16 | NAND_NO_SUBPAGE_WRITE | NAND_NO_AUTOINCR;
+ nand->IO_ADDR_R = nand->IO_ADDR_W = doc->virtadr + DOC_IOSPACE_DATA;
+ nand->controller = &nand->hwcontrol;
+ spin_lock_init(&nand->controller->lock);
+ init_waitqueue_head(&nand->controller->wq);
+
+ /* methods */
+ nand->cmdfunc = docg4_command;
+ nand->waitfunc = docg4_wait;
+ nand->select_chip = docg4_select_chip;
+ nand->read_byte = docg4_read_byte;
+ nand->block_markbad = docg4_block_markbad;
+ nand->read_buf = docg4_read_buf;
+ nand->write_buf = docg4_write_buf16;
+ nand->scan_bbt = nand_default_bbt;
+ nand->erase_cmd = docg4_erase_block;
+ nand->ecc.read_page = docg4_read_page;
+ nand->ecc.write_page = docg4_write_page;
+ nand->ecc.read_page_raw = docg4_read_page_raw;
+ nand->ecc.write_page_raw = docg4_write_page_raw;
+ nand->ecc.read_oob = docg4_read_oob;
+ nand->ecc.write_oob = docg4_write_oob;
+
+ /*
+ * The way the nand infrastructure code is written, a memory-based bbt
+ * is not created if NAND_SKIP_BBTSCAN is set. With no memory bbt,
+ * nand->block_bad() is called. So when ignoring bad blocks, we skip
+ * the scan and define a dummy block_bad() which always returns 0.
+ */
+ if (ignore_badblocks) {
+ nand->options |= NAND_SKIP_BBTSCAN;
+ nand->block_bad = docg4_block_neverbad;
+ }
+
+}
+
+static int __init read_id_reg(struct mtd_info *mtd, struct nand_chip *nand)
+{
+ struct docg4_priv *doc = nand->priv;
+ void __iomem *docptr = doc->virtadr;
+ uint16_t id1, id2;
+
+ /* check for presence of g4 chip by reading id registers */
+ id1 = readw(docptr + DOC_CHIPID);
+ id1 = readw(docptr + DOCG4_MYSTERY_REG);
+ id2 = readw(docptr + DOC_CHIPID_INV);
+ id2 = readw(docptr + DOCG4_MYSTERY_REG);
+
+ if (id1 == DOCG4_IDREG1_VALUE && id2 == DOCG4_IDREG2_VALUE) {
+ dev_info(doc->dev,
+ "NAND device: 128MiB Diskonchip G4 detected\n");
+ return 0;
+ }
+
+ return -ENODEV;
+}
+
+static int __init probe_docg4(struct platform_device *pdev)
+{
+ struct mtd_info *mtd;
+ struct nand_chip *nand;
+ void __iomem *virtadr;
+ struct docg4_priv *doc;
+ int len, retval;
+ struct resource *r;
+ struct device *dev = &pdev->dev;
+ const struct docg4_nand_platform_data *pdata = dev->platform_data;
+
+ if (pdata == NULL) {
+ dev_err(&pdev->dev, "no platform data!\n");
+ return -EINVAL;
+ }
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (r == NULL) {
+ dev_err(dev, "no io memory resource defined!\n");
+ return -ENODEV;
+ }
+
+ virtadr = ioremap(r->start, resource_size(r));
+ if (!virtadr) {
+ dev_err(dev, "Diskonchip ioremap failed: "
+ "0x%x bytes at 0x%x\n",
+ resource_size(r), r->start);
+ return -EIO;
+ }
+
+ len = sizeof(struct mtd_info) + sizeof(struct nand_chip) +
+ sizeof(struct docg4_priv);
+ mtd = kzalloc(len, GFP_KERNEL);
+ if (mtd == NULL) {
+ retval = -ENOMEM;
+ goto fail;
+ }
+ nand = (struct nand_chip *) (mtd + 1);
+ doc = (struct docg4_priv *) (nand + 1);
+ mtd->priv = nand;
+ nand->priv = doc;
+ mtd->owner = THIS_MODULE;
+ doc->virtadr = virtadr;
+ doc->dev = dev;
+
+ init_mtd_structs(mtd);
+
+ /* initialize kernel bch algorithm */
+ doc->bch = init_bch(DOCG4_M, DOCG4_T, DOCG4_PRIMITIVE_POLY);
+ if (doc->bch == NULL) {
+ retval = -EINVAL;
+ goto fail;
+ }
+
+ platform_set_drvdata(pdev, doc);
+
+ reset(mtd, nand);
+ retval = read_id_reg(mtd, nand);
+ if (retval == -ENODEV) {
+ dev_warn(dev, "No diskonchip G4 device found.\n");
+ goto fail;
+ }
+
+ retval = nand_scan_tail(mtd);
+ if (retval)
+ goto fail;
+
+ retval = read_factory_bbt(mtd);
+ if (retval)
+ goto fail;
+
+ retval = mtd_device_register(mtd, NULL, 0);
+ if (retval)
+ goto fail;
+
+ if (pdata->nr_partitions > 0) {
+ int i;
+ for (i = 0; i < pdata->nr_partitions; i++)
+ pdata->partitions[i].ecclayout = &docg4_oobinfo;
+ retval = mtd_device_register(mtd, pdata->partitions,
+ pdata->nr_partitions);
+ }
+ if (retval)
+ goto fail;
+
+ doc->mtd = mtd;
+ return 0;
+
+ fail:
+ iounmap(virtadr);
+ if (mtd) {
+ /* re-declarations avoid compiler warning */
+ struct nand_chip *nand = mtd->priv;
+ struct docg4_priv *doc = nand->priv;
+ nand_release(mtd); /* deletes partitions and mtd devices */
+ platform_set_drvdata(pdev, NULL);
+ free_bch(doc->bch);
+ kfree(mtd);
+ }
+
+ return retval;
+}
+
+static int __exit cleanup_docg4(struct platform_device *pdev)
+{
+ struct docg4_priv *doc = platform_get_drvdata(pdev);
+ nand_release(doc->mtd);
+ iounmap(doc->virtadr);
+ platform_set_drvdata(pdev, NULL);
+ free_bch(doc->bch);
+ kfree(doc);
+ return 0;
+}
+
+static struct platform_driver docg4_driver = {
+ .driver = {
+ .name = "docg4",
+ .owner = THIS_MODULE,
+ },
+ .remove = __exit_p(cleanup_docg4),
+};
+
+static int __init docg4_init(void)
+{
+ return platform_driver_probe(&docg4_driver, probe_docg4);
+}
+
+static void __exit docg4_exit(void)
+{
+ platform_driver_unregister(&docg4_driver);
+}
+
+module_init(docg4_init);
+module_exit(docg4_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mike Dunn");
+MODULE_DESCRIPTION("M-Systems DiskOnChip G4 device driver");
new file mode 100644
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2011 Mike Dunn <mikedunn@newsguy.com>
+ *
+ * Nand mtd driver for M-Systems DiskOnChip G4 device
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+struct docg4_nand_platform_data {
+ struct mtd_partition *partitions;
+ unsigned int nr_partitions;
+};
This is a nand driver for the diskonchip G4 in my Palm Treo680. It's been fairly well tested; it passes the nandtest utility in mtd-utils, and also the kernel tests mtd_pagetest and mtd_readtest. Common mtd-utils work as well (nanddump, nandwrite, flash_erase, ...). A ubifs was created on it and seems to be working well, though more stress testing is needed. Since version 2: - Replace DEBUG macros defined in mtd.h with dev_dbg (intended for V2). Compiles against l2-mtd kernel (tested against mtd-2.6 kernel). - Fix oversight I noticed which would cause read errors in user oob bytes not to be corrected (and array out-of-bounds to occur) - Implement Ivan's suggestion for detecting bit flips on read of a blank page. Signed-off-by: Mike Dunn <mikedunn@newsguy.com> --- Still hoping for some comments ragarding suitability of the nand interface for these devices. drivers/mtd/nand/Kconfig | 12 + drivers/mtd/nand/Makefile | 1 + drivers/mtd/nand/docg4.c | 1220 +++++++++++++++++++++++++++++++++++++++++++++ include/linux/mtd/docg4.h | 24 + 4 files changed, 1257 insertions(+), 0 deletions(-) create mode 100644 drivers/mtd/nand/docg4.c create mode 100644 include/linux/mtd/docg4.h