[MTD] OneNAND: Add support for auto-placement of out-of-band data

Enable the use of oob operation mode MTD_OOB_AUTO with OneNAND.
Note that MTD_OOB_RAW is still not supported.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>

2 files changed, 171 insertions, 37 deletions

diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index daf298948b9b..67efbc70019e 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -787,20 +787,60 @@ static int onenand_read(struct mtd_info *mtd, loff_t from, size_t len,
 }
 
 /**
+ * onenand_transfer_auto_oob - [Internal] oob auto-placement transfer
+ * @param mtd           MTD device structure
+ * @param buf           destination address
+ * @param column        oob offset to read from
+ * @param thislen       oob length to read
+ */
+static int onenand_transfer_auto_oob(struct mtd_info *mtd, uint8_t *buf, int column,
+                                int thislen)
+{
+        struct onenand_chip *this = mtd->priv;
+        struct nand_oobfree *free;
+        int readcol = column;
+        int readend = column + thislen;
+        int lastgap = 0;
+        uint8_t *oob_buf = this->page_buf + mtd->writesize;
+
+        for (free = this->ecclayout->oobfree; free->length; ++free) {
+                if (readcol >= lastgap)
+                        readcol += free->offset - lastgap;
+                if (readend >= lastgap)
+                        readend += free->offset - lastgap;
+                lastgap = free->offset + free->length;
+        }
+        this->read_bufferram(mtd, ONENAND_SPARERAM, oob_buf + readcol,
+                             readcol, readend - readcol);
+        for (free = this->ecclayout->oobfree; free->length; ++free) {
+                int free_end = free->offset + free->length;
+                if (free->offset < readend && free_end > readcol) {
+                        int st = max_t(int,free->offset,readcol);
+                        int ed = min_t(int,free_end,readend);
+                        int n = ed - st;
+                        memcpy(buf, oob_buf + st, n);
+                        buf += n;
+                }
+        }
+        return 0;
+}
+
+/**
  * onenand_do_read_oob - [MTD Interface] OneNAND read out-of-band
  * @param mtd           MTD device structure
  * @param from          offset to read from
  * @param len           number of bytes to read
  * @param retlen        pointer to variable to store the number of read bytes
  * @param buf           the databuffer to put data
+ * @param mode          operation mode
  *
  * OneNAND read out-of-band data from the spare area
  */
 int onenand_do_read_oob(struct mtd_info *mtd, loff_t from, size_t len,
-                        size_t *retlen, u_char *buf)
+                        size_t *retlen, u_char *buf, mtd_oob_mode_t mode)
 {
         struct onenand_chip *this = mtd->priv;
-        int read = 0, thislen, column;
+        int read = 0, thislen, column, oobsize;
         int ret = 0;
 
         DEBUG(MTD_DEBUG_LEVEL3, "onenand_read_oob: from = 0x%08x, len = %i\n", (unsigned int) from, (int) len);
@@ -808,21 +848,33 @@ int onenand_do_read_oob(struct mtd_info *mtd, loff_t from, size_t len,
         /* Initialize return length value */
         *retlen = 0;
 
+        if (mode == MTD_OOB_AUTO)
+                oobsize = this->ecclayout->oobavail;
+        else
+                oobsize = mtd->oobsize;
+
+        column = from & (mtd->oobsize - 1);
+
+        if (unlikely(column >= oobsize)) {
+                DEBUG(MTD_DEBUG_LEVEL0, "onenand_read_oob: Attempted to start read outside oob\n");
+                return -EINVAL;
+        }
+
         /* Do not allow reads past end of device */
-        if (unlikely((from + len) > mtd->size)) {
-                DEBUG(MTD_DEBUG_LEVEL0, "onenand_read_oob: Attempt read beyond end of device\n");
+        if (unlikely(from >= mtd->size ||
+                     column + len > ((mtd->size >> this->page_shift) -
+                                     (from >> this->page_shift)) * oobsize)) {
+                DEBUG(MTD_DEBUG_LEVEL0, "onenand_read_oob: Attempted to read beyond end of device\n");
                 return -EINVAL;
         }
 
         /* Grab the lock and see if the device is available */
         onenand_get_device(mtd, FL_READING);
 
-        column = from & (mtd->oobsize - 1);
-
         while (read < len) {
                 cond_resched();
 
-                thislen = mtd->oobsize - column;
+                thislen = oobsize - column;
                 thislen = min_t(int, thislen, len);
 
                 this->command(mtd, ONENAND_CMD_READOOB, from, mtd->oobsize);
@@ -832,7 +884,10 @@ int onenand_do_read_oob(struct mtd_info *mtd, loff_t from, size_t len,
                 ret = this->wait(mtd, FL_READING);
                 /* First copy data and check return value for ECC handling */
 
-                this->read_bufferram(mtd, ONENAND_SPARERAM, buf, column, thislen);
+                if (mode == MTD_OOB_AUTO)
+                        onenand_transfer_auto_oob(mtd, buf, column, thislen);
+                else
+                        this->read_bufferram(mtd, ONENAND_SPARERAM, buf, column, thislen);
 
                 if (ret) {
                         DEBUG(MTD_DEBUG_LEVEL0, "onenand_read_oob: read failed = 0x%x\n", ret);
@@ -871,10 +926,18 @@ out:
 static int onenand_read_oob(struct mtd_info *mtd, loff_t from,
                             struct mtd_oob_ops *ops)
 {
-        BUG_ON(ops->mode != MTD_OOB_PLACE);
-
+        switch (ops->mode)
+        {
+        case MTD_OOB_PLACE:
+        case MTD_OOB_AUTO:
+                break;
+        case MTD_OOB_RAW:
+                return -EINVAL; /* Not implemented yet */
+        default:
+                return -EINVAL;
+        }
         return onenand_do_read_oob(mtd, from + ops->ooboffs, ops->ooblen,
-                                   &ops->oobretlen, ops->oobbuf);
+                                   &ops->oobretlen, ops->oobbuf, ops->mode);
 }
 
 #ifdef CONFIG_MTD_ONENAND_VERIFY_WRITE
@@ -883,14 +946,12 @@ static int onenand_read_oob(struct mtd_info *mtd, loff_t from,
  * @param mtd           MTD device structure
  * @param buf           the databuffer to verify
  * @param to            offset to read from
- * @param len           number of bytes to read and compare
  *
  */
-static int onenand_verify_oob(struct mtd_info *mtd, const u_char *buf, loff_t to, int len)
+static int onenand_verify_oob(struct mtd_info *mtd, const u_char *buf, loff_t to)
 {
         struct onenand_chip *this = mtd->priv;
-        char *readp = this->page_buf;
-        int column = to & (mtd->oobsize - 1);
+        char *readp = this->page_buf + mtd->writesize;
         int status, i;
 
         this->command(mtd, ONENAND_CMD_READOOB, to, mtd->oobsize);
@@ -899,9 +960,8 @@ static int onenand_verify_oob(struct mtd_info *mtd, const u_char *buf, loff_t to
         if (status)
                 return status;
 
-        this->read_bufferram(mtd, ONENAND_SPARERAM, readp, column, len);
-
-        for(i = 0; i < len; i++)
+        this->read_bufferram(mtd, ONENAND_SPARERAM, readp, 0, mtd->oobsize);
+        for(i = 0; i < mtd->oobsize; i++)
                 if (buf[i] != 0xFF && buf[i] != readp[i])
                         return -EBADMSG;
 
@@ -1060,20 +1120,59 @@ static int onenand_write(struct mtd_info *mtd, loff_t to, size_t len,
 }
 
 /**
+ * onenand_fill_auto_oob - [Internal] oob auto-placement transfer
+ * @param mtd           MTD device structure
+ * @param oob_buf       oob buffer
+ * @param buf           source address
+ * @param column        oob offset to write to
+ * @param thislen       oob length to write
+ */
+static int onenand_fill_auto_oob(struct mtd_info *mtd, u_char *oob_buf,
+                                  const u_char *buf, int column, int thislen)
+{
+        struct onenand_chip *this = mtd->priv;
+        struct nand_oobfree *free;
+        int writecol = column;
+        int writeend = column + thislen;
+        int lastgap = 0;
+
+        for (free = this->ecclayout->oobfree; free->length; ++free) {
+                if (writecol >= lastgap)
+                        writecol += free->offset - lastgap;
+                if (writeend >= lastgap)
+                        writeend += free->offset - lastgap;
+                lastgap = free->offset + free->length;
+        }
+        writeend = mtd->oobsize;
+        for (free = this->ecclayout->oobfree; free->length; ++free) {
+                int free_end = free->offset + free->length;
+                if (free->offset < writeend && free_end > writecol) {
+                        int st = max_t(int,free->offset,writecol);
+                        int ed = min_t(int,free_end,writeend);
+                        int n = ed - st;
+                        memcpy(oob_buf + st, buf, n);
+                        buf += n;
+                }
+        }
+        return 0;
+}
+
+/**
  * onenand_do_write_oob - [Internal] OneNAND write out-of-band
  * @param mtd           MTD device structure
  * @param to            offset to write to
  * @param len           number of bytes to write
  * @param retlen        pointer to variable to store the number of written bytes
  * @param buf           the data to write
+ * @param mode          operation mode
  *
  * OneNAND write out-of-band
  */
 static int onenand_do_write_oob(struct mtd_info *mtd, loff_t to, size_t len,
-                                size_t *retlen, const u_char *buf)
+                                size_t *retlen, const u_char *buf, mtd_oob_mode_t mode)
 {
         struct onenand_chip *this = mtd->priv;
-        int column, ret = 0;
+        int column, ret = 0, oobsize;
         int written = 0;
 
         DEBUG(MTD_DEBUG_LEVEL3, "onenand_write_oob: to = 0x%08x, len = %i\n", (unsigned int) to, (int) len);
@@ -1081,9 +1180,23 @@ static int onenand_do_write_oob(struct mtd_info *mtd, loff_t to, size_t len,
         /* Initialize retlen, in case of early exit */
         *retlen = 0;
 
-        /* Do not allow writes past end of device */
-        if (unlikely((to + len) > mtd->size)) {
-                DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_oob: Attempt write to past end of device\n");
+        if (mode == MTD_OOB_AUTO)
+                oobsize = this->ecclayout->oobavail;
+        else
+                oobsize = mtd->oobsize;
+
+        column = to & (mtd->oobsize - 1);
+
+        if (unlikely(column >= oobsize)) {
+                DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_oob: Attempted to start write outside oob\n");
+                return -EINVAL;
+        }
+
+        /* Do not allow reads past end of device */
+        if (unlikely(to >= mtd->size ||
+                     column + len > ((mtd->size >> this->page_shift) -
+                                     (to >> this->page_shift)) * oobsize)) {
+                DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_oob: Attempted to write past end of device\n");
                 return -EINVAL;
         }
 
@@ -1092,18 +1205,19 @@ static int onenand_do_write_oob(struct mtd_info *mtd, loff_t to, size_t len,
 
         /* Loop until all data write */
         while (written < len) {
-                int thislen = min_t(int, mtd->oobsize, len - written);
+                int thislen = min_t(int, oobsize, len - written);
 
                 cond_resched();
 
-                column = to & (mtd->oobsize - 1);
-
                 this->command(mtd, ONENAND_CMD_BUFFERRAM, to, mtd->oobsize);
 
                 /* We send data to spare ram with oobsize
                  * to prevent byte access */
                 memset(this->page_buf, 0xff, mtd->oobsize);
-                memcpy(this->page_buf + column, buf, thislen);
+                if (mode == MTD_OOB_AUTO)
+                        onenand_fill_auto_oob(mtd, this->page_buf, buf, column, thislen);
+                else
+                        memcpy(this->page_buf + column, buf, thislen);
                 this->write_bufferram(mtd, ONENAND_SPARERAM, this->page_buf, 0, mtd->oobsize);
 
                 this->command(mtd, ONENAND_CMD_PROGOOB, to, mtd->oobsize);
@@ -1112,11 +1226,11 @@ static int onenand_do_write_oob(struct mtd_info *mtd, loff_t to, size_t len,
 
                 ret = this->wait(mtd, FL_WRITING);
                 if (ret) {
-                        DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_oob: write filaed %d\n", ret);
+                        DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_oob: write failed %d\n", ret);
                         goto out;
                 }
 
-                ret = onenand_verify_oob(mtd, buf, to, thislen);
+                ret = onenand_verify_oob(mtd, this->page_buf, to);
                 if (ret) {
                         DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_oob: verify failed %d\n", ret);
                         goto out;
@@ -1127,8 +1241,9 @@ static int onenand_do_write_oob(struct mtd_info *mtd, loff_t to, size_t len,
                 if (written == len)
                         break;
 
-                to += thislen;
+                to += mtd->writesize;
                 buf += thislen;
+                column = 0;
         }
 
 out:
@@ -1149,10 +1264,18 @@ out:
 static int onenand_write_oob(struct mtd_info *mtd, loff_t to,
                              struct mtd_oob_ops *ops)
 {
-        BUG_ON(ops->mode != MTD_OOB_PLACE);
-
+        switch (ops->mode)
+        {
+        case MTD_OOB_PLACE:
+        case MTD_OOB_AUTO:
+                break;
+        case MTD_OOB_RAW:
+                return -EINVAL; /* Not implemented yet */
+        default:
+                return -EINVAL;
+        }
         return onenand_do_write_oob(mtd, to + ops->ooboffs, ops->ooblen,
-                                    &ops->oobretlen, ops->oobbuf);
+                                    &ops->oobretlen, ops->oobbuf, ops->mode);
 }
 
 /**
@@ -1318,7 +1441,7 @@ static int onenand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
 
         /* We write two bytes, so we dont have to mess with 16 bit access */
         ofs += mtd->oobsize + (bbm->badblockpos & ~0x01);
-        return onenand_do_write_oob(mtd, ofs , 2, &retlen, buf);
+        return onenand_do_write_oob(mtd, ofs , 2, &retlen, buf, MTD_OOB_PLACE);
 }
 
 /**
@@ -1612,7 +1735,7 @@ static int do_otp_lock(struct mtd_info *mtd, loff_t from, size_t len,
         this->command(mtd, ONENAND_CMD_OTP_ACCESS, 0, 0);
         this->wait(mtd, FL_OTPING);
 
-        ret = onenand_do_write_oob(mtd, from, len, retlen, buf);
+        ret = onenand_do_write_oob(mtd, from, len, retlen, buf, MTD_OOB_PLACE);
 
         /* Exit OTP access mode */
         this->command(mtd, ONENAND_CMD_RESET, 0, 0);
@@ -2019,6 +2142,7 @@ static void onenand_resume(struct mtd_info *mtd)
  */
 int onenand_scan(struct mtd_info *mtd, int maxchips)
 {
+        int i;
         struct onenand_chip *this = mtd->priv;
 
         if (!this->read_word)
@@ -2090,6 +2214,16 @@ int onenand_scan(struct mtd_info *mtd, int maxchips)
         }
 
         this->subpagesize = mtd->writesize >> mtd->subpage_sft;
+
+        /*
+         * The number of bytes available for a client to place data into
+         * the out of band area
+         */
+        this->ecclayout->oobavail = 0;
+        for (i = 0; this->ecclayout->oobfree[i].length; i++)
+                this->ecclayout->oobavail +=
+                        this->ecclayout->oobfree[i].length;
+
         mtd->ecclayout = this->ecclayout;
 
         /* Fill in remaining MTD driver data */
diff --git a/drivers/mtd/onenand/onenand_bbt.c b/drivers/mtd/onenand/onenand_bbt.c
index aa46b7f6f496..acea9a1a7297 100644
--- a/drivers/mtd/onenand/onenand_bbt.c
+++ b/drivers/mtd/onenand/onenand_bbt.c
@@ -18,7 +18,7 @@
 #include <linux/mtd/compatmac.h>
 
 extern int onenand_do_read_oob(struct mtd_info *mtd, loff_t from, size_t len,
-                               size_t *retlen, u_char *buf);
+                               size_t *retlen, u_char *buf, mtd_oob_mode_t mode);
 
 /**
  * check_short_pattern - [GENERIC] check if a pattern is in the buffer
@@ -91,7 +91,7 @@ static int create_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
                         /* No need to read pages fully,
                          * just read required OOB bytes */
                         ret = onenand_do_read_oob(mtd, from + j * mtd->writesize + bd->offs,
-                                                  readlen, &retlen, &buf[0]);
+                                                  readlen, &retlen, &buf[0], MTD_OOB_PLACE);
 
                         /* If it is a initial bad block, just ignore it */
                         if (ret && !(ret & ONENAND_CTRL_LOAD))