mtd: add bcmring nand driver

Signed-off-by: Leo Hao Chen <leochen@broadcom.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 213 insertions, 0 deletions

diff --git a/drivers/mtd/nand/bcm_umi_bch.c b/drivers/mtd/nand/bcm_umi_bch.c
new file mode 100644
index 0000000..a930666
--- /dev/null
+++ b/drivers/mtd/nand/bcm_umi_bch.c
@@ -0,0 +1,213 @@
+/*****************************************************************************
+* Copyright 2004 - 2009 Broadcom Corporation.  All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+/* ---- Include Files ---------------------------------------------------- */
+#include "nand_bcm_umi.h"
+
+/* ---- External Variable Declarations ----------------------------------- */
+/* ---- External Function Prototypes ------------------------------------- */
+/* ---- Public Variables ------------------------------------------------- */
+/* ---- Private Constants and Types -------------------------------------- */
+
+/* ---- Private Function Prototypes -------------------------------------- */
+static int bcm_umi_bch_read_page_hwecc(struct mtd_info *mtd,
+	struct nand_chip *chip, uint8_t *buf, int page);
+static void bcm_umi_bch_write_page_hwecc(struct mtd_info *mtd,
+	struct nand_chip *chip, const uint8_t *buf);
+
+/* ---- Private Variables ------------------------------------------------ */
+
+/*
+** nand_hw_eccoob
+** New oob placement block for use with hardware ecc generation.
+*/
+static struct nand_ecclayout nand_hw_eccoob_512 = {
+	/* Reserve 5 for BI indicator */
+	.oobfree = {
+#if (NAND_ECC_NUM_BYTES > 3)
+		    {.offset = 0, .length = 2}
+#else
+		    {.offset = 0, .length = 5},
+		    {.offset = 6, .length = 7}
+#endif
+		    }
+};
+
+/*
+** We treat the OOB for a 2K page as if it were 4 512 byte oobs,
+** except the BI is at byte 0.
+*/
+static struct nand_ecclayout nand_hw_eccoob_2048 = {
+	/* Reserve 0 as BI indicator */
+	.oobfree = {
+#if (NAND_ECC_NUM_BYTES > 10)
+		    {.offset = 1, .length = 2},
+#elif (NAND_ECC_NUM_BYTES > 7)
+		    {.offset = 1, .length = 5},
+		    {.offset = 16, .length = 6},
+		    {.offset = 32, .length = 6},
+		    {.offset = 48, .length = 6}
+#else
+		    {.offset = 1, .length = 8},
+		    {.offset = 16, .length = 9},
+		    {.offset = 32, .length = 9},
+		    {.offset = 48, .length = 9}
+#endif
+		    }
+};
+
+/* We treat the OOB for a 4K page as if it were 8 512 byte oobs,
+ * except the BI is at byte 0. */
+static struct nand_ecclayout nand_hw_eccoob_4096 = {
+	/* Reserve 0 as BI indicator */
+	.oobfree = {
+#if (NAND_ECC_NUM_BYTES > 10)
+		    {.offset = 1, .length = 2},
+		    {.offset = 16, .length = 3},
+		    {.offset = 32, .length = 3},
+		    {.offset = 48, .length = 3},
+		    {.offset = 64, .length = 3},
+		    {.offset = 80, .length = 3},
+		    {.offset = 96, .length = 3},
+		    {.offset = 112, .length = 3}
+#else
+		    {.offset = 1, .length = 5},
+		    {.offset = 16, .length = 6},
+		    {.offset = 32, .length = 6},
+		    {.offset = 48, .length = 6},
+		    {.offset = 64, .length = 6},
+		    {.offset = 80, .length = 6},
+		    {.offset = 96, .length = 6},
+		    {.offset = 112, .length = 6}
+#endif
+		    }
+};
+
+/* ---- Private Functions ------------------------------------------------ */
+/* ==== Public Functions ================================================= */
+
+/****************************************************************************
+*
+*  bcm_umi_bch_read_page_hwecc - hardware ecc based page read function
+*  @mtd:	mtd info structure
+*  @chip:	nand chip info structure
+*  @buf:	buffer to store read data
+*
+***************************************************************************/
+static int bcm_umi_bch_read_page_hwecc(struct mtd_info *mtd,
+				       struct nand_chip *chip, uint8_t * buf,
+						 int page)
+{
+	int sectorIdx = 0;
+	int eccsize = chip->ecc.size;
+	int eccsteps = chip->ecc.steps;
+	uint8_t *datap = buf;
+	uint8_t eccCalc[NAND_ECC_NUM_BYTES];
+	int sectorOobSize = mtd->oobsize / eccsteps;
+	int stat;
+
+	for (sectorIdx = 0; sectorIdx < eccsteps;
+			sectorIdx++, datap += eccsize) {
+		if (sectorIdx > 0) {
+			/* Seek to page location within sector */
+			chip->cmdfunc(mtd, NAND_CMD_RNDOUT, sectorIdx * eccsize,
+				      -1);
+		}
+
+		/* Enable hardware ECC before reading the buf */
+		nand_bcm_umi_bch_enable_read_hwecc();
+
+		/* Read in data */
+		bcm_umi_nand_read_buf(mtd, datap, eccsize);
+
+		/* Pause hardware ECC after reading the buf */
+		nand_bcm_umi_bch_pause_read_ecc_calc();
+
+		/* Read the OOB ECC */
+		chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
+			      mtd->writesize + sectorIdx * sectorOobSize, -1);
+		nand_bcm_umi_bch_read_oobEcc(mtd->writesize, eccCalc,
+					     NAND_ECC_NUM_BYTES,
+					     chip->oob_poi +
+					     sectorIdx * sectorOobSize);
+
+		/* Correct any ECC detected errors */
+		stat =
+		    nand_bcm_umi_bch_correct_page(datap, eccCalc,
+						  NAND_ECC_NUM_BYTES);
+
+		/* Update Stats */
+		if (stat < 0) {
+#if defined(NAND_BCM_UMI_DEBUG)
+			printk(KERN_WARNING "%s uncorr_err sectorIdx=%d\n",
+			       __func__, sectorIdx);
+			printk(KERN_WARNING
+			       "%s data %02x %02x %02x %02x "
+					 "%02x %02x %02x %02x\n",
+			       __func__, datap[0], datap[1], datap[2], datap[3],
+			       datap[4], datap[5], datap[6], datap[7]);
+			printk(KERN_WARNING
+			       "%s ecc  %02x %02x %02x %02x "
+					 "%02x %02x %02x %02x %02x %02x "
+					 "%02x %02x %02x\n",
+			       __func__, eccCalc[0], eccCalc[1], eccCalc[2],
+			       eccCalc[3], eccCalc[4], eccCalc[5], eccCalc[6],
+			       eccCalc[7], eccCalc[8], eccCalc[9], eccCalc[10],
+			       eccCalc[11], eccCalc[12]);
+			BUG();
+#endif
+			mtd->ecc_stats.failed++;
+		} else {
+#if defined(NAND_BCM_UMI_DEBUG)
+			if (stat > 0) {
+				printk(KERN_INFO
+				       "%s %d correctable_errors detected\n",
+				       __func__, stat);
+			}
+#endif
+			mtd->ecc_stats.corrected += stat;
+		}
+	}
+	return 0;
+}
+
+/****************************************************************************
+*
+*  bcm_umi_bch_write_page_hwecc - hardware ecc based page write function
+*  @mtd:	mtd info structure
+*  @chip:	nand chip info structure
+*  @buf:	data buffer
+*
+***************************************************************************/
+static void bcm_umi_bch_write_page_hwecc(struct mtd_info *mtd,
+	struct nand_chip *chip, const uint8_t *buf)
+{
+	int sectorIdx = 0;
+	int eccsize = chip->ecc.size;
+	int eccsteps = chip->ecc.steps;
+	const uint8_t *datap = buf;
+	uint8_t *oobp = chip->oob_poi;
+	int sectorOobSize = mtd->oobsize / eccsteps;
+
+	for (sectorIdx = 0; sectorIdx < eccsteps;
+	     sectorIdx++, datap += eccsize, oobp += sectorOobSize) {
+		/* Enable hardware ECC before writing the buf */
+		nand_bcm_umi_bch_enable_write_hwecc();
+		bcm_umi_nand_write_buf(mtd, datap, eccsize);
+		nand_bcm_umi_bch_write_oobEcc(mtd->writesize, oobp,
+					      NAND_ECC_NUM_BYTES);
+	}
+
+	bcm_umi_nand_write_buf(mtd, chip->oob_poi, mtd->oobsize);
+}