[PATCH] mtd/nand : workaround for Freescale FCM to support large-page Nand chip
b35362 at freescale.com
b35362 at freescale.com
Mon Sep 26 01:10:06 EDT 2011
From: Liu Shuo <b35362 at freescale.com>
Freescale FCM controller has a 2K size limitation of buffer RAM. In order
to support the Nand flash chip whose page size is larger than 2K bytes,
we read/write 2k data repeatedly by issuing FIR_OP_RB/FIR_OP_WB and save
them to a large buffer.
Signed-off-by: Liu Shuo <b35362 at freescale.com>
Signed-off-by: Li Yang <leoli at freescale.com>
---
drivers/mtd/nand/fsl_elbc_nand.c | 182 ++++++++++++++++++++++++++++++++++---
1 files changed, 167 insertions(+), 15 deletions(-)
diff --git a/drivers/mtd/nand/fsl_elbc_nand.c b/drivers/mtd/nand/fsl_elbc_nand.c
index a212116..183e532 100644
--- a/drivers/mtd/nand/fsl_elbc_nand.c
+++ b/drivers/mtd/nand/fsl_elbc_nand.c
@@ -76,6 +76,9 @@ struct fsl_elbc_fcm_ctrl {
unsigned int oob; /* Non zero if operating on OOB data */
unsigned int counter; /* counter for the initializations */
char *oob_poi; /* Place to write ECC after read back */
+
+ char *buffer;
+ int page_size; /* the mutiple of 2048 */
};
/* These map to the positions used by the FCM hardware ECC generator */
@@ -151,6 +154,44 @@ static struct nand_bbt_descr bbt_mirror_descr = {
};
/*=================================*/
+static void io_to_buffer(struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl,
+ int subpage, int off, int len, int oob)
+{
+ void *src, *dst;
+
+ if (!len)
+ len = (oob ? 64 : 2048);
+
+ if (oob)
+ dst = elbc_fcm_ctrl->buffer + elbc_fcm_ctrl->page_size +
+ subpage * 64 + off;
+ else
+ dst = elbc_fcm_ctrl->buffer + subpage * 2048 + off;
+
+ src = elbc_fcm_ctrl->addr + (oob ? 2048 : 0) + off;
+ memcpy_fromio(dst, src, len);
+}
+
+static void buffer_to_io(struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl,
+ int subpage, int off, int len, int oob)
+{
+ void *src, *dst;
+
+ if (!len)
+ len = (oob ? 64 : 2048);
+
+ if (oob)
+ src = elbc_fcm_ctrl->buffer + elbc_fcm_ctrl->page_size +
+ subpage * 64 + off;
+ else
+ src = elbc_fcm_ctrl->buffer + subpage * 2048 + off;
+
+ dst = elbc_fcm_ctrl->addr + (oob ? 2048 : 0) + off;
+
+ memcpy_toio(dst, src, len);
+ in_8(elbc_fcm_ctrl->addr);
+}
+
/*
* Set up the FCM hardware block and page address fields, and the fcm
@@ -167,15 +208,14 @@ static void set_addr(struct mtd_info *mtd, int column, int page_addr, int oob)
elbc_fcm_ctrl->page = page_addr;
- out_be32(&lbc->fbar,
- page_addr >> (chip->phys_erase_shift - chip->page_shift));
-
if (priv->page_size) {
+ out_be32(&lbc->fbar, page_addr >> 6);
out_be32(&lbc->fpar,
((page_addr << FPAR_LP_PI_SHIFT) & FPAR_LP_PI) |
(oob ? FPAR_LP_MS : 0) | column);
buf_num = (page_addr & 1) << 2;
} else {
+ out_be32(&lbc->fbar, page_addr >> 5);
out_be32(&lbc->fpar,
((page_addr << FPAR_SP_PI_SHIFT) & FPAR_SP_PI) |
(oob ? FPAR_SP_MS : 0) | column);
@@ -187,7 +227,7 @@ static void set_addr(struct mtd_info *mtd, int column, int page_addr, int oob)
/* for OOB data point to the second half of the buffer */
if (oob)
- elbc_fcm_ctrl->index += priv->page_size ? 2048 : 512;
+ elbc_fcm_ctrl->index += mtd->writesize;
dev_vdbg(priv->dev, "set_addr: bank=%d, "
"elbc_fcm_ctrl->addr=0x%p (0x%p), "
@@ -286,6 +326,7 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
struct fsl_lbc_ctrl *ctrl = priv->ctrl;
struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
+ int i;
elbc_fcm_ctrl->use_mdr = 0;
@@ -314,6 +355,27 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
fsl_elbc_do_read(chip, 0);
fsl_elbc_run_command(mtd);
+
+ if (priv->page_size <= 1)
+ return;
+
+ /* Continue to read the rest bytes if writesize > 2048 */
+ io_to_buffer(elbc_fcm_ctrl, 0, 0, 0, 0);
+ io_to_buffer(elbc_fcm_ctrl, 0, 0, 0, 1);
+
+ for (i = 1; i < priv->page_size; i++) {
+ /*
+ * Maybe there are some reasons of FCM hardware timming,
+ * we must insert a FIR_OP_NOP(0x00) before FIR_OP_RB.
+ */
+ out_be32(&lbc->fir, FIR_OP_RB << FIR_OP1_SHIFT);
+ out_be32(&lbc->fbcr, 0);
+ fsl_elbc_run_command(mtd);
+
+ io_to_buffer(elbc_fcm_ctrl, i, 0, 0, 0);
+ io_to_buffer(elbc_fcm_ctrl, i, 0, 0, 1);
+ }
+
return;
/* READOOB reads only the OOB because no ECC is performed. */
@@ -322,13 +384,31 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
"fsl_elbc_cmdfunc: NAND_CMD_READOOB, page_addr:"
" 0x%x, column: 0x%x.\n", page_addr, column);
- out_be32(&lbc->fbcr, mtd->oobsize - column);
- set_addr(mtd, column, page_addr, 1);
+ out_be32(&lbc->fbcr, 64);
+ set_addr(mtd, 0, page_addr, 1);
elbc_fcm_ctrl->read_bytes = mtd->writesize + mtd->oobsize;
+ elbc_fcm_ctrl->index += column;
fsl_elbc_do_read(chip, 1);
fsl_elbc_run_command(mtd);
+
+ if (priv->page_size <= 1)
+ return;
+
+ if (column < 64)
+ io_to_buffer(elbc_fcm_ctrl, 0, 0, 0, 1);
+
+ out_be32(&lbc->fpar, in_be32(&lbc->fpar) & ~FPAR_LP_MS);
+ for (i = 1; i < priv->page_size; i++) {
+ fsl_elbc_do_read(chip, 0);
+ out_be32(&lbc->fir, FIR_OP_RB << FIR_OP1_SHIFT);
+ out_be32(&lbc->fbcr, 2112);
+ fsl_elbc_run_command(mtd);
+
+ if (column < (64 * (i + 1)))
+ io_to_buffer(elbc_fcm_ctrl, i, 0, 0, 1);
+ }
return;
/* READID must read all 5 possible bytes while CEB is active */
@@ -396,7 +476,14 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
(NAND_CMD_SEQIN << FCR_CMD2_SHIFT) |
(NAND_CMD_PAGEPROG << FCR_CMD3_SHIFT);
- if (priv->page_size) {
+ if (priv->page_size > 1) {
+ /* writesize > 2048 */
+ out_be32(&lbc->fir,
+ (FIR_OP_CM2 << FIR_OP0_SHIFT) |
+ (FIR_OP_CA << FIR_OP1_SHIFT) |
+ (FIR_OP_PA << FIR_OP2_SHIFT) |
+ (FIR_OP_WB << FIR_OP3_SHIFT));
+ } else if (priv->page_size) {
out_be32(&lbc->fir,
(FIR_OP_CM2 << FIR_OP0_SHIFT) |
(FIR_OP_CA << FIR_OP1_SHIFT) |
@@ -453,8 +540,29 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
full_page = 1;
}
+ if (priv->page_size > 1) {
+ buffer_to_io(elbc_fcm_ctrl, 0, 0, 0, 0);
+ buffer_to_io(elbc_fcm_ctrl, 0, 0, 0, 1);
+ }
+
fsl_elbc_run_command(mtd);
+ for (i = 1; i < priv->page_size; i++) {
+ elbc_fcm_ctrl->use_mdr = 1;
+ if (i == priv->page_size - 1)
+ out_be32(&lbc->fir,
+ (FIR_OP_WB << FIR_OP1_SHIFT) |
+ (FIR_OP_CM3 << FIR_OP2_SHIFT) |
+ (FIR_OP_CW1 << FIR_OP3_SHIFT) |
+ (FIR_OP_RS << FIR_OP4_SHIFT));
+ else
+ out_be32(&lbc->fir, FIR_OP_WB << FIR_OP1_SHIFT);
+ out_be32(&lbc->fbcr, 0);
+ buffer_to_io(elbc_fcm_ctrl, i, 0, 0, 0);
+ buffer_to_io(elbc_fcm_ctrl, i, 0, 0, 1);
+ fsl_elbc_run_command(mtd);
+ }
+
/* Read back the page in order to fill in the ECC for the
* caller. Is this really needed?
*/
@@ -541,7 +649,14 @@ static void fsl_elbc_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
len = bufsize - elbc_fcm_ctrl->index;
}
- memcpy_toio(&elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index], buf, len);
+ if (mtd->writesize > 2048)
+ memcpy(&elbc_fcm_ctrl->buffer[elbc_fcm_ctrl->index],
+ buf, len);
+ else {
+ memcpy_toio(&elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index],
+ buf, len);
+ }
+
/*
* This is workaround for the weird elbc hangs during nand write,
* Scott Wood says: "...perhaps difference in how long it takes a
@@ -587,7 +702,12 @@ static void fsl_elbc_read_buf(struct mtd_info *mtd, u8 *buf, int len)
avail = min((unsigned int)len,
elbc_fcm_ctrl->read_bytes - elbc_fcm_ctrl->index);
- memcpy_fromio(buf, &elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index], avail);
+ if (mtd->writesize > 2048)
+ memcpy(buf, &elbc_fcm_ctrl->buffer[elbc_fcm_ctrl->index],
+ avail);
+ else
+ memcpy_fromio(buf, &elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index],
+ avail);
elbc_fcm_ctrl->index += avail;
if (len > avail)
@@ -623,10 +743,16 @@ static int fsl_elbc_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
return -EINVAL;
}
- for (i = 0; i < len; i++)
- if (in_8(&elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index + i])
- != buf[i])
- break;
+ if (mtd->writesize > 2048)
+ for (i = 0; i < len; i++)
+ if (elbc_fcm_ctrl->buffer[elbc_fcm_ctrl->index + i]
+ != buf[i])
+ break;
+ else
+ for (i = 0; i < len; i++)
+ if (in_8(&elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index + i])
+ != buf[i])
+ break;
elbc_fcm_ctrl->index += len;
return i == len && elbc_fcm_ctrl->status == LTESR_CC ? 0 : -EIO;
@@ -655,6 +781,7 @@ static int fsl_elbc_chip_init_tail(struct mtd_info *mtd)
struct fsl_elbc_mtd *priv = chip->priv;
struct fsl_lbc_ctrl *ctrl = priv->ctrl;
struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
+ struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
unsigned int al;
/* calculate FMR Address Length field */
@@ -705,12 +832,17 @@ static int fsl_elbc_chip_init_tail(struct mtd_info *mtd)
dev_dbg(priv->dev, "fsl_elbc_init: mtd->oobsize = %d\n",
mtd->oobsize);
+ kfree(elbc_fcm_ctrl->buffer);
+ elbc_fcm_ctrl->buffer = NULL;
+
/* adjust Option Register and ECC to match Flash page size */
if (mtd->writesize == 512) {
priv->page_size = 0;
clrbits32(&lbc->bank[priv->bank].or, OR_FCM_PGS);
- } else if (mtd->writesize == 2048) {
- priv->page_size = 1;
+ } else if (mtd->writesize >= 2048) {
+ /* page_size = writesize / 2048 */
+ priv->page_size = mtd->writesize >> 11;
+
setbits32(&lbc->bank[priv->bank].or, OR_FCM_PGS);
/* adjust ecc setup if needed */
if ((in_be32(&lbc->bank[priv->bank].br) & BR_DECC) ==
@@ -721,6 +853,15 @@ static int fsl_elbc_chip_init_tail(struct mtd_info *mtd)
&fsl_elbc_oob_lp_eccm0;
chip->badblock_pattern = &largepage_memorybased;
}
+ elbc_fcm_ctrl->page_size = mtd->writesize;
+
+ /* re-malloc if pagesize > 2048*/
+ if (mtd->writesize > 2048) {
+ elbc_fcm_ctrl->buffer = kmalloc(mtd->writesize +
+ mtd->oobsize, GFP_KERNEL);
+ if (!elbc_fcm_ctrl->buffer)
+ return -ENOMEM;
+ }
} else {
dev_err(priv->dev,
"fsl_elbc_init: page size %d is not supported\n",
@@ -888,6 +1029,17 @@ static int __devinit fsl_elbc_nand_probe(struct platform_device *pdev)
goto err;
}
elbc_fcm_ctrl->counter++;
+ /*
+ * Freescale FCM controller has a 2K size limitation of buffer
+ * RAM, so elbc_fcm_ctrl->buffer have to be used if writesize
+ * of chip is greater than 2048.
+ * We malloc a large enough buffer at this point, because we
+ * don't know writesize before calling nand_scan(). We will
+ * re-malloc later if needed.
+ */
+ elbc_fcm_ctrl->buffer = kmalloc(4096 * 6, GFP_KERNEL);
+ if (!elbc_fcm_ctrl->buffer)
+ return -ENOMEM;
spin_lock_init(&elbc_fcm_ctrl->controller.lock);
init_waitqueue_head(&elbc_fcm_ctrl->controller.wq);
--
1.7.1
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