[U-Boot] [PATCH 5/5] mtd/nand: workaround for Freescale FCM to support 4k pagesize Nand chip

Shengzhou Liu Shengzhou.Liu at freescale.com
Thu Dec 8 11:49:12 CET 2011


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: Shengzhou Liu <Shengzhou.Liu at freescale.com>
Signed-off-by: Liu Shuo <b35362 at freescale.com>
---
 drivers/mtd/nand/fsl_elbc_nand.c |  279 +++++++++++++++++++++++++++++++++----
 1 files changed, 248 insertions(+), 31 deletions(-)

diff --git a/drivers/mtd/nand/fsl_elbc_nand.c b/drivers/mtd/nand/fsl_elbc_nand.c
index 52362b1..3983c8c 100644
--- a/drivers/mtd/nand/fsl_elbc_nand.c
+++ b/drivers/mtd/nand/fsl_elbc_nand.c
@@ -64,7 +64,6 @@ struct fsl_elbc_mtd {
 	struct device *dev;
 	int bank;               /* Chip select bank number           */
 	u8 __iomem *vbase;      /* Chip select base virtual address  */
-	int page_size;          /* NAND page size (0=512, 1=2048)    */
 	unsigned int fmr;       /* FCM Flash Mode Register value     */
 };
 
@@ -85,6 +84,8 @@ struct fsl_elbc_ctrl {
 	unsigned int mdr;        /* UPM/FCM Data Register value           */
 	unsigned int use_mdr;    /* Non zero if the MDR is to be set      */
 	unsigned int oob;        /* Non zero if operating on OOB data     */
+	char *buffer;            /* just used when pagesize is greater    */
+				 /* than FCM RAM 2K limitation		  */
 };
 
 /* These map to the positions used by the FCM hardware ECC generator */
@@ -159,6 +160,44 @@ static struct nand_bbt_descr bbt_mirror_descr = {
 	.pattern = mirror_pattern,
 };
 
+static void io_to_buffer(struct mtd_info *mtd, int subpage, int oob)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+	void *src, *dst;
+	int len = (oob ? 64 : 2048);
+
+	/* for emulating 4096+ bytes NAND using 2048-byte FCM RAM */
+	if (oob)
+		dst = ctrl->buffer + mtd->writesize + subpage * 64;
+	else
+		dst = ctrl->buffer + subpage * 2048;
+
+	src = ctrl->addr + (oob ? 2048 : 0);
+	memcpy_fromio(dst, src, len);
+}
+
+static void buffer_to_io(struct mtd_info *mtd, int subpage, int oob)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct fsl_elbc_mtd *priv = chip->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+	void *src, *dst;
+	int len = (oob ? 64 : 2048);
+
+	if (oob)
+		src = ctrl->buffer + mtd->writesize + subpage * 64;
+	else
+		src = ctrl->buffer + subpage * 2048;
+
+	dst = ctrl->addr + (oob ? 2048 : 0);
+
+	memcpy_toio(dst, src, len);
+	/* See the in_8() in fsl_elbc_write_buf() */
+	in_8(ctrl->addr);
+}
+
 /*=================================*/
 
 /*
@@ -175,7 +214,7 @@ static void set_addr(struct mtd_info *mtd, int column, int page_addr, int oob)
 
 	ctrl->page = page_addr;
 
-	if (priv->page_size) {
+	if (mtd->writesize >= 2048) {
 		out_be32(&lbc->fbar, page_addr >> 6);
 		out_be32(&lbc->fpar,
 			 ((page_addr << FPAR_LP_PI_SHIFT) & FPAR_LP_PI) |
@@ -194,7 +233,7 @@ 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)
-		ctrl->index += priv->page_size ? 2048 : 512;
+		ctrl->index += mtd->writesize;
 
 	vdbg("set_addr: bank=%d, ctrl->addr=0x%p (0x%p), "
 	     "index %x, pes %d ps %d\n",
@@ -256,13 +295,14 @@ static int fsl_elbc_run_command(struct mtd_info *mtd)
 	return ctrl->status == LTESR_CC ? 0 : -EIO;
 }
 
-static void fsl_elbc_do_read(struct nand_chip *chip, int oob)
+static void fsl_elbc_do_read(struct mtd_info *mtd, int oob)
 {
+	struct nand_chip *chip = mtd->priv;
 	struct fsl_elbc_mtd *priv = chip->priv;
 	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
 	fsl_lbc_t *lbc = ctrl->regs;
 
-	if (priv->page_size) {
+	if (mtd->writesize >= 2048) {
 		out_be32(&lbc->fir,
 			 (FIR_OP_CW0 << FIR_OP0_SHIFT) |
 			 (FIR_OP_CA  << FIR_OP1_SHIFT) |
@@ -295,6 +335,7 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
 	struct fsl_elbc_mtd *priv = chip->priv;
 	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
 	fsl_lbc_t *lbc = ctrl->regs;
+	int i, nps = mtd->writesize / 2048;
 
 	ctrl->use_mdr = 0;
 
@@ -319,8 +360,27 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
 		ctrl->read_bytes = mtd->writesize + mtd->oobsize;
 		ctrl->index += column;
 
-		fsl_elbc_do_read(chip, 0);
+		fsl_elbc_do_read(mtd, 0);
 		fsl_elbc_run_command(mtd);
+
+		if (mtd->writesize <= 2048)
+			return;
+
+		/* Continue to read the rest bytes if writesize > 2048 */
+		io_to_buffer(mtd, 0, 0);
+		io_to_buffer(mtd, 0, 1);
+		/*
+		 * Maybe there are some reasons of FCM hardware timing,
+		 * we must insert a FIR_OP_NOP(0x00) before FIR_OP_RB.
+		 */
+		out_be32(&lbc->fir, FIR_OP_RB << FIR_OP1_SHIFT);
+
+		for (i = 1; i < nps; i++) {
+			fsl_elbc_run_command(mtd);
+			io_to_buffer(mtd, i, 0);
+			io_to_buffer(mtd, i, 1);
+		}
+
 		return;
 
 	/* READOOB reads only the OOB because no ECC is performed. */
@@ -328,14 +388,35 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
 		vdbg("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);
+		if (mtd->writesize <= 2048) {
+			out_be32(&lbc->fbcr, mtd->oobsize - column);
+			set_addr(mtd, column, page_addr, 1);
+		} else {
+			out_be32(&lbc->fbcr, 64);
+			set_addr(mtd, 0, page_addr, 1);
+			ctrl->index += column;
+		}
 
 		ctrl->read_bytes = mtd->writesize + mtd->oobsize;
-
-		fsl_elbc_do_read(chip, 1);
+		fsl_elbc_do_read(mtd, 1);
 		fsl_elbc_run_command(mtd);
 
+		if (mtd->writesize <= 2048)
+			return;
+
+		if (column < 64)
+			io_to_buffer(mtd, 0, 1);
+
+		out_be32(&lbc->fpar, in_be32(&lbc->fpar) & ~FPAR_LP_MS);
+		out_be32(&lbc->fir, FIR_OP_RB << FIR_OP1_SHIFT);
+		out_be32(&lbc->fbcr, 2112);
+
+		for (i = 1; i < nps; i++) {
+			fsl_elbc_run_command(mtd);
+			if (column < (64 * (i + 1)))
+				io_to_buffer(mtd, i, 1);
+		}
+
 		return;
 
 	/* READID must read all 5 possible bytes while CEB is active */
@@ -395,9 +476,28 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
 		     page_addr, column);
 
 		ctrl->column = column;
-		ctrl->oob = 0;
+		if (column >= mtd->writesize) {
+			/* OOB area */
+			column -= mtd->writesize;
+			ctrl->oob = 1;
+		} else {
+			ctrl->oob = 0;
+		}
 
-		if (priv->page_size) {
+		if (mtd->writesize > 2048) {
+			/* writesize > 2048 */
+			fcr = (NAND_CMD_STATUS << FCR_CMD1_SHIFT) |
+				(NAND_CMD_SEQIN << FCR_CMD2_SHIFT) |
+				(NAND_CMD_PAGEPROG << FCR_CMD3_SHIFT);
+			if (ctrl->oob)
+				fcr |= NAND_CMD_RNDIN << FCR_CMD0_SHIFT;
+
+			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 (mtd->writesize == 2048) {
 			fcr = (NAND_CMD_SEQIN << FCR_CMD0_SHIFT) |
 			      (NAND_CMD_PAGEPROG << FCR_CMD1_SHIFT);
 
@@ -419,11 +519,9 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
 				 (FIR_OP_WB  << FIR_OP4_SHIFT) |
 				 (FIR_OP_CW1 << FIR_OP5_SHIFT));
 
-			if (column >= mtd->writesize) {
+			if (ctrl->oob) {
 				/* OOB area --> READOOB */
-				column -= mtd->writesize;
 				fcr |= NAND_CMD_READOOB << FCR_CMD0_SHIFT;
-				ctrl->oob = 1;
 			} else if (column < 256) {
 				/* First 256 bytes --> READ0 */
 				fcr |= NAND_CMD_READ0 << FCR_CMD0_SHIFT;
@@ -434,12 +532,19 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
 		}
 
 		out_be32(&lbc->fcr, fcr);
-		set_addr(mtd, column, page_addr, ctrl->oob);
+		if (column >= mtd->writesize && mtd->writesize > 2048) {
+			/* for write oob && writesize > 2048 */
+			set_addr(mtd, 0, page_addr, 0);
+			ctrl->index = column;
+		} else {
+			set_addr(mtd, column, page_addr, ctrl->oob);
+		}
 		return;
 	}
 
 	/* PAGEPROG reuses all of the setup from SEQIN and adds the length */
 	case NAND_CMD_PAGEPROG: {
+		int pos;
 		vdbg("fsl_elbc_cmdfunc: NAND_CMD_PAGEPROG "
 		     "writing %d bytes.\n", ctrl->index);
 
@@ -447,14 +552,71 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
 		 * then set the exact length, otherwise use a full page
 		 * write so the HW generates the ECC.
 		 */
+
 		if (ctrl->oob || ctrl->column != 0 ||
-		    ctrl->index != mtd->writesize + mtd->oobsize)
-			out_be32(&lbc->fbcr, ctrl->index);
-		else
+				ctrl->index != mtd->writesize + mtd->oobsize) {
+			if (ctrl->oob && mtd->writesize > 2048) {
+				out_be32(&lbc->fbcr, 64);
+			} else {
+				out_be32(&lbc->fbcr, ctrl->index -
+					ctrl->column);
+			}
+		} else {
 			out_be32(&lbc->fbcr, 0);
+		}
+
+		if (mtd->writesize > 2048) {
+			if (!ctrl->oob)
+				buffer_to_io(mtd, 0, 0);
+			buffer_to_io(mtd, 0, 1);
+		}
 
 		fsl_elbc_run_command(mtd);
 
+		if (mtd->writesize <= 2048)
+			return;
+
+		if (ctrl->oob) {
+			pos = 2048;
+			out_be32(&lbc->fir,
+				(FIR_OP_CM0 << FIR_OP0_SHIFT) |
+				(FIR_OP_UA  << FIR_OP1_SHIFT) |
+				(FIR_OP_UA  << FIR_OP2_SHIFT) |
+				(FIR_OP_WB  << FIR_OP3_SHIFT));
+
+			for (i = 1; i < nps; i++) {
+				pos += 2112;
+				ctrl->mdr = pos;
+				ctrl->use_mdr = 1;
+				if (i == nps - 1) {
+					out_be32(&lbc->fir,
+						(FIR_OP_CM0 << FIR_OP1_SHIFT) |
+						(FIR_OP_UA  << FIR_OP2_SHIFT) |
+						(FIR_OP_UA  << FIR_OP3_SHIFT) |
+						(FIR_OP_WB  << FIR_OP4_SHIFT) |
+						(FIR_OP_CM3 << FIR_OP5_SHIFT) |
+						(FIR_OP_CW1 << FIR_OP6_SHIFT) |
+						(FIR_OP_RS  << FIR_OP7_SHIFT));
+				}
+				buffer_to_io(mtd, i, 1);
+				fsl_elbc_run_command(mtd);
+			}
+		} else {
+			out_be32(&lbc->fir, FIR_OP_WB << FIR_OP1_SHIFT);
+			for (i = 1; i < nps; i++) {
+				if (i == nps - 1) {
+					ctrl->use_mdr = 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));
+				}
+				buffer_to_io(mtd, i, 0);
+				buffer_to_io(mtd, i, 1);
+				fsl_elbc_run_command(mtd);
+			}
+		}
 		return;
 	}
 
@@ -475,6 +637,7 @@ static void fsl_elbc_cmdfunc(struct mtd_info *mtd, unsigned int command,
 		 * write-protected, even when it is not.
 		 */
 		out_8(ctrl->addr, in_8(ctrl->addr) | NAND_STATUS_WP);
+		ctrl->buffer[0] = in_8(ctrl->addr);
 		return;
 
 	/* RESET without waiting for the ready line */
@@ -521,7 +684,11 @@ static void fsl_elbc_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
 		len = bufsize - ctrl->index;
 	}
 
-	memcpy_toio(&ctrl->addr[ctrl->index], buf, len);
+	if (mtd->writesize > 2048)
+		memcpy(&ctrl->buffer[ctrl->index], buf, len);
+	else
+		memcpy_toio(&ctrl->addr[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
@@ -545,8 +712,13 @@ static u8 fsl_elbc_read_byte(struct mtd_info *mtd)
 	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
 
 	/* If there are still bytes in the FCM, then use the next byte. */
-	if (ctrl->index < ctrl->read_bytes)
-		return in_8(&ctrl->addr[ctrl->index++]);
+	if (ctrl->index < ctrl->read_bytes) {
+		int index = ctrl->index++;
+		if (mtd->writesize > 2048)
+			return ctrl->buffer[index];
+		else
+			return in_8(&ctrl->addr[index]);
+	}
 
 	printf("read_byte beyond end of buffer\n");
 	return ERR_BYTE;
@@ -566,7 +738,10 @@ static void fsl_elbc_read_buf(struct mtd_info *mtd, u8 *buf, int len)
 		return;
 
 	avail = min((unsigned int)len, ctrl->read_bytes - ctrl->index);
-	memcpy_fromio(buf, &ctrl->addr[ctrl->index], avail);
+	if (mtd->writesize > 2048)
+		memcpy(buf, &ctrl->buffer[ctrl->index], avail);
+	else
+		memcpy_fromio(buf, &ctrl->addr[ctrl->index], avail);
 	ctrl->index += avail;
 
 	if (len > avail)
@@ -600,9 +775,17 @@ static int fsl_elbc_verify_buf(struct mtd_info *mtd,
 		return -EINVAL;
 	}
 
-	for (i = 0; i < len; i++)
-		if (in_8(&ctrl->addr[ctrl->index + i]) != buf[i])
-			break;
+	if (mtd->writesize > 2048) {
+		for (i = 0; i < len; i++) {
+			if (ctrl->buffer[ctrl->index + i] != buf[i])
+				break;
+		}
+	} else {
+		for (i = 0; i < len; i++) {
+			if (in_8(&ctrl->addr[ctrl->index + i]) != buf[i])
+				break;
+		}
+	}
 
 	ctrl->index += len;
 	return i == len && ctrl->status == LTESR_CC ? 0 : -EIO;
@@ -639,6 +822,7 @@ static int fsl_elbc_wait(struct mtd_info *mtd, struct nand_chip *chip)
 	 * write-protected, even when it is not.
 	 */
 	out_8(ctrl->addr, in_8(ctrl->addr) | NAND_STATUS_WP);
+	ctrl->buffer[0] = in_8(ctrl->addr);
 	return fsl_elbc_read_byte(mtd);
 }
 
@@ -668,11 +852,11 @@ static void fsl_elbc_write_page(struct mtd_info *mtd,
 
 static struct fsl_elbc_ctrl *elbc_ctrl;
 
-static void fsl_elbc_ctrl_init(void)
+static int fsl_elbc_ctrl_init(void)
 {
 	elbc_ctrl = kzalloc(sizeof(*elbc_ctrl), GFP_KERNEL);
 	if (!elbc_ctrl)
-		return;
+		return -ENOMEM;
 
 	elbc_ctrl->regs = LBC_BASE_ADDR;
 
@@ -686,6 +870,22 @@ static void fsl_elbc_ctrl_init(void)
 	elbc_ctrl->read_bytes = 0;
 	elbc_ctrl->index = 0;
 	elbc_ctrl->addr = NULL;
+
+	/*
+	 * 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 kmalloc a 9 KB buffer for now (if there will be 16k pagesize,
+	 * modify it later) at this point, because we don't know writesize
+	 * before calling nand_scan(). We will re-malloc later if needed.
+	 */
+	elbc_ctrl->buffer = kmalloc(1024 * 8 + 1024, GFP_KERNEL);
+	if (!elbc_ctrl->buffer) {
+		printf("failed to allocate memory for elbc_ctrl->buffer\n");
+		return -ENOMEM;
+	}
+
+	return 0;
 }
 
 int board_nand_init(struct nand_chip *nand)
@@ -694,8 +894,7 @@ int board_nand_init(struct nand_chip *nand)
 	uint32_t br = 0, or = 0;
 
 	if (!elbc_ctrl) {
-		fsl_elbc_ctrl_init();
-		if (!elbc_ctrl)
+		if (fsl_elbc_ctrl_init())
 			return -1;
 	}
 
@@ -784,7 +983,6 @@ int board_nand_init(struct nand_chip *nand)
 
 	/* Large-page-specific setup */
 	if (or & OR_FCM_PGS) {
-		priv->page_size = 1;
 		nand->badblock_pattern = &largepage_memorybased;
 
 		/* adjust ecc setup if needed */
@@ -798,3 +996,22 @@ int board_nand_init(struct nand_chip *nand)
 
 	return 0;
 }
+
+
+int board_nand_init_tail(struct mtd_info *mtd, struct nand_chip *nand)
+{
+	struct fsl_elbc_mtd *priv = nand->priv;
+	struct fsl_elbc_ctrl *ctrl = priv->ctrl;
+
+	kfree(ctrl->buffer);
+	ctrl->buffer = NULL;
+
+	if (mtd->writesize > 2048) {
+		ctrl->buffer = kmalloc(mtd->writesize + mtd->oobsize,
+						GFP_KERNEL);
+		if (!ctrl->buffer)
+			return -ENOMEM;
+	}
+
+	return 0;
+}
-- 
1.6.4




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