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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/mtd/nand/fsmc_nand.c
Initial import
Diffstat (limited to 'drivers/mtd/nand/fsmc_nand.c')
-rw-r--r--drivers/mtd/nand/fsmc_nand.c1242
1 files changed, 1242 insertions, 0 deletions
diff --git a/drivers/mtd/nand/fsmc_nand.c b/drivers/mtd/nand/fsmc_nand.c
new file mode 100644
index 000000000..e58af4bfa
--- /dev/null
+++ b/drivers/mtd/nand/fsmc_nand.c
@@ -0,0 +1,1242 @@
+/*
+ * drivers/mtd/nand/fsmc_nand.c
+ *
+ * ST Microelectronics
+ * Flexible Static Memory Controller (FSMC)
+ * Driver for NAND portions
+ *
+ * Copyright © 2010 ST Microelectronics
+ * Vipin Kumar <vipin.kumar@st.com>
+ * Ashish Priyadarshi
+ *
+ * Based on drivers/mtd/nand/nomadik_nand.c
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/resource.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/nand_ecc.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/mtd/partitions.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/mtd/fsmc.h>
+#include <linux/amba/bus.h>
+#include <mtd/mtd-abi.h>
+
+static struct nand_ecclayout fsmc_ecc1_128_layout = {
+ .eccbytes = 24,
+ .eccpos = {2, 3, 4, 18, 19, 20, 34, 35, 36, 50, 51, 52,
+ 66, 67, 68, 82, 83, 84, 98, 99, 100, 114, 115, 116},
+ .oobfree = {
+ {.offset = 8, .length = 8},
+ {.offset = 24, .length = 8},
+ {.offset = 40, .length = 8},
+ {.offset = 56, .length = 8},
+ {.offset = 72, .length = 8},
+ {.offset = 88, .length = 8},
+ {.offset = 104, .length = 8},
+ {.offset = 120, .length = 8}
+ }
+};
+
+static struct nand_ecclayout fsmc_ecc1_64_layout = {
+ .eccbytes = 12,
+ .eccpos = {2, 3, 4, 18, 19, 20, 34, 35, 36, 50, 51, 52},
+ .oobfree = {
+ {.offset = 8, .length = 8},
+ {.offset = 24, .length = 8},
+ {.offset = 40, .length = 8},
+ {.offset = 56, .length = 8},
+ }
+};
+
+static struct nand_ecclayout fsmc_ecc1_16_layout = {
+ .eccbytes = 3,
+ .eccpos = {2, 3, 4},
+ .oobfree = {
+ {.offset = 8, .length = 8},
+ }
+};
+
+/*
+ * ECC4 layout for NAND of pagesize 8192 bytes & OOBsize 256 bytes. 13*16 bytes
+ * of OB size is reserved for ECC, Byte no. 0 & 1 reserved for bad block and 46
+ * bytes are free for use.
+ */
+static struct nand_ecclayout fsmc_ecc4_256_layout = {
+ .eccbytes = 208,
+ .eccpos = { 2, 3, 4, 5, 6, 7, 8,
+ 9, 10, 11, 12, 13, 14,
+ 18, 19, 20, 21, 22, 23, 24,
+ 25, 26, 27, 28, 29, 30,
+ 34, 35, 36, 37, 38, 39, 40,
+ 41, 42, 43, 44, 45, 46,
+ 50, 51, 52, 53, 54, 55, 56,
+ 57, 58, 59, 60, 61, 62,
+ 66, 67, 68, 69, 70, 71, 72,
+ 73, 74, 75, 76, 77, 78,
+ 82, 83, 84, 85, 86, 87, 88,
+ 89, 90, 91, 92, 93, 94,
+ 98, 99, 100, 101, 102, 103, 104,
+ 105, 106, 107, 108, 109, 110,
+ 114, 115, 116, 117, 118, 119, 120,
+ 121, 122, 123, 124, 125, 126,
+ 130, 131, 132, 133, 134, 135, 136,
+ 137, 138, 139, 140, 141, 142,
+ 146, 147, 148, 149, 150, 151, 152,
+ 153, 154, 155, 156, 157, 158,
+ 162, 163, 164, 165, 166, 167, 168,
+ 169, 170, 171, 172, 173, 174,
+ 178, 179, 180, 181, 182, 183, 184,
+ 185, 186, 187, 188, 189, 190,
+ 194, 195, 196, 197, 198, 199, 200,
+ 201, 202, 203, 204, 205, 206,
+ 210, 211, 212, 213, 214, 215, 216,
+ 217, 218, 219, 220, 221, 222,
+ 226, 227, 228, 229, 230, 231, 232,
+ 233, 234, 235, 236, 237, 238,
+ 242, 243, 244, 245, 246, 247, 248,
+ 249, 250, 251, 252, 253, 254
+ },
+ .oobfree = {
+ {.offset = 15, .length = 3},
+ {.offset = 31, .length = 3},
+ {.offset = 47, .length = 3},
+ {.offset = 63, .length = 3},
+ {.offset = 79, .length = 3},
+ {.offset = 95, .length = 3},
+ {.offset = 111, .length = 3},
+ {.offset = 127, .length = 3},
+ {.offset = 143, .length = 3},
+ {.offset = 159, .length = 3},
+ {.offset = 175, .length = 3},
+ {.offset = 191, .length = 3},
+ {.offset = 207, .length = 3},
+ {.offset = 223, .length = 3},
+ {.offset = 239, .length = 3},
+ {.offset = 255, .length = 1}
+ }
+};
+
+/*
+ * ECC4 layout for NAND of pagesize 4096 bytes & OOBsize 224 bytes. 13*8 bytes
+ * of OOB size is reserved for ECC, Byte no. 0 & 1 reserved for bad block & 118
+ * bytes are free for use.
+ */
+static struct nand_ecclayout fsmc_ecc4_224_layout = {
+ .eccbytes = 104,
+ .eccpos = { 2, 3, 4, 5, 6, 7, 8,
+ 9, 10, 11, 12, 13, 14,
+ 18, 19, 20, 21, 22, 23, 24,
+ 25, 26, 27, 28, 29, 30,
+ 34, 35, 36, 37, 38, 39, 40,
+ 41, 42, 43, 44, 45, 46,
+ 50, 51, 52, 53, 54, 55, 56,
+ 57, 58, 59, 60, 61, 62,
+ 66, 67, 68, 69, 70, 71, 72,
+ 73, 74, 75, 76, 77, 78,
+ 82, 83, 84, 85, 86, 87, 88,
+ 89, 90, 91, 92, 93, 94,
+ 98, 99, 100, 101, 102, 103, 104,
+ 105, 106, 107, 108, 109, 110,
+ 114, 115, 116, 117, 118, 119, 120,
+ 121, 122, 123, 124, 125, 126
+ },
+ .oobfree = {
+ {.offset = 15, .length = 3},
+ {.offset = 31, .length = 3},
+ {.offset = 47, .length = 3},
+ {.offset = 63, .length = 3},
+ {.offset = 79, .length = 3},
+ {.offset = 95, .length = 3},
+ {.offset = 111, .length = 3},
+ {.offset = 127, .length = 97}
+ }
+};
+
+/*
+ * ECC4 layout for NAND of pagesize 4096 bytes & OOBsize 128 bytes. 13*8 bytes
+ * of OOB size is reserved for ECC, Byte no. 0 & 1 reserved for bad block & 22
+ * bytes are free for use.
+ */
+static struct nand_ecclayout fsmc_ecc4_128_layout = {
+ .eccbytes = 104,
+ .eccpos = { 2, 3, 4, 5, 6, 7, 8,
+ 9, 10, 11, 12, 13, 14,
+ 18, 19, 20, 21, 22, 23, 24,
+ 25, 26, 27, 28, 29, 30,
+ 34, 35, 36, 37, 38, 39, 40,
+ 41, 42, 43, 44, 45, 46,
+ 50, 51, 52, 53, 54, 55, 56,
+ 57, 58, 59, 60, 61, 62,
+ 66, 67, 68, 69, 70, 71, 72,
+ 73, 74, 75, 76, 77, 78,
+ 82, 83, 84, 85, 86, 87, 88,
+ 89, 90, 91, 92, 93, 94,
+ 98, 99, 100, 101, 102, 103, 104,
+ 105, 106, 107, 108, 109, 110,
+ 114, 115, 116, 117, 118, 119, 120,
+ 121, 122, 123, 124, 125, 126
+ },
+ .oobfree = {
+ {.offset = 15, .length = 3},
+ {.offset = 31, .length = 3},
+ {.offset = 47, .length = 3},
+ {.offset = 63, .length = 3},
+ {.offset = 79, .length = 3},
+ {.offset = 95, .length = 3},
+ {.offset = 111, .length = 3},
+ {.offset = 127, .length = 1}
+ }
+};
+
+/*
+ * ECC4 layout for NAND of pagesize 2048 bytes & OOBsize 64 bytes. 13*4 bytes of
+ * OOB size is reserved for ECC, Byte no. 0 & 1 reserved for bad block and 10
+ * bytes are free for use.
+ */
+static struct nand_ecclayout fsmc_ecc4_64_layout = {
+ .eccbytes = 52,
+ .eccpos = { 2, 3, 4, 5, 6, 7, 8,
+ 9, 10, 11, 12, 13, 14,
+ 18, 19, 20, 21, 22, 23, 24,
+ 25, 26, 27, 28, 29, 30,
+ 34, 35, 36, 37, 38, 39, 40,
+ 41, 42, 43, 44, 45, 46,
+ 50, 51, 52, 53, 54, 55, 56,
+ 57, 58, 59, 60, 61, 62,
+ },
+ .oobfree = {
+ {.offset = 15, .length = 3},
+ {.offset = 31, .length = 3},
+ {.offset = 47, .length = 3},
+ {.offset = 63, .length = 1},
+ }
+};
+
+/*
+ * ECC4 layout for NAND of pagesize 512 bytes & OOBsize 16 bytes. 13 bytes of
+ * OOB size is reserved for ECC, Byte no. 4 & 5 reserved for bad block and One
+ * byte is free for use.
+ */
+static struct nand_ecclayout fsmc_ecc4_16_layout = {
+ .eccbytes = 13,
+ .eccpos = { 0, 1, 2, 3, 6, 7, 8,
+ 9, 10, 11, 12, 13, 14
+ },
+ .oobfree = {
+ {.offset = 15, .length = 1},
+ }
+};
+
+/*
+ * ECC placement definitions in oobfree type format.
+ * There are 13 bytes of ecc for every 512 byte block and it has to be read
+ * consecutively and immediately after the 512 byte data block for hardware to
+ * generate the error bit offsets in 512 byte data.
+ * Managing the ecc bytes in the following way makes it easier for software to
+ * read ecc bytes consecutive to data bytes. This way is similar to
+ * oobfree structure maintained already in generic nand driver
+ */
+static struct fsmc_eccplace fsmc_ecc4_lp_place = {
+ .eccplace = {
+ {.offset = 2, .length = 13},
+ {.offset = 18, .length = 13},
+ {.offset = 34, .length = 13},
+ {.offset = 50, .length = 13},
+ {.offset = 66, .length = 13},
+ {.offset = 82, .length = 13},
+ {.offset = 98, .length = 13},
+ {.offset = 114, .length = 13}
+ }
+};
+
+static struct fsmc_eccplace fsmc_ecc4_sp_place = {
+ .eccplace = {
+ {.offset = 0, .length = 4},
+ {.offset = 6, .length = 9}
+ }
+};
+
+/**
+ * struct fsmc_nand_data - structure for FSMC NAND device state
+ *
+ * @pid: Part ID on the AMBA PrimeCell format
+ * @mtd: MTD info for a NAND flash.
+ * @nand: Chip related info for a NAND flash.
+ * @partitions: Partition info for a NAND Flash.
+ * @nr_partitions: Total number of partition of a NAND flash.
+ *
+ * @ecc_place: ECC placing locations in oobfree type format.
+ * @bank: Bank number for probed device.
+ * @clk: Clock structure for FSMC.
+ *
+ * @read_dma_chan: DMA channel for read access
+ * @write_dma_chan: DMA channel for write access to NAND
+ * @dma_access_complete: Completion structure
+ *
+ * @data_pa: NAND Physical port for Data.
+ * @data_va: NAND port for Data.
+ * @cmd_va: NAND port for Command.
+ * @addr_va: NAND port for Address.
+ * @regs_va: FSMC regs base address.
+ */
+struct fsmc_nand_data {
+ u32 pid;
+ struct mtd_info mtd;
+ struct nand_chip nand;
+ struct mtd_partition *partitions;
+ unsigned int nr_partitions;
+
+ struct fsmc_eccplace *ecc_place;
+ unsigned int bank;
+ struct device *dev;
+ enum access_mode mode;
+ struct clk *clk;
+
+ /* DMA related objects */
+ struct dma_chan *read_dma_chan;
+ struct dma_chan *write_dma_chan;
+ struct completion dma_access_complete;
+
+ struct fsmc_nand_timings *dev_timings;
+
+ dma_addr_t data_pa;
+ void __iomem *data_va;
+ void __iomem *cmd_va;
+ void __iomem *addr_va;
+ void __iomem *regs_va;
+
+ void (*select_chip)(uint32_t bank, uint32_t busw);
+};
+
+/* Assert CS signal based on chipnr */
+static void fsmc_select_chip(struct mtd_info *mtd, int chipnr)
+{
+ struct nand_chip *chip = mtd->priv;
+ struct fsmc_nand_data *host;
+
+ host = container_of(mtd, struct fsmc_nand_data, mtd);
+
+ switch (chipnr) {
+ case -1:
+ chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
+ break;
+ case 0:
+ case 1:
+ case 2:
+ case 3:
+ if (host->select_chip)
+ host->select_chip(chipnr,
+ chip->options & NAND_BUSWIDTH_16);
+ break;
+
+ default:
+ BUG();
+ }
+}
+
+/*
+ * fsmc_cmd_ctrl - For facilitaing Hardware access
+ * This routine allows hardware specific access to control-lines(ALE,CLE)
+ */
+static void fsmc_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
+{
+ struct nand_chip *this = mtd->priv;
+ struct fsmc_nand_data *host = container_of(mtd,
+ struct fsmc_nand_data, mtd);
+ void __iomem *regs = host->regs_va;
+ unsigned int bank = host->bank;
+
+ if (ctrl & NAND_CTRL_CHANGE) {
+ u32 pc;
+
+ if (ctrl & NAND_CLE) {
+ this->IO_ADDR_R = host->cmd_va;
+ this->IO_ADDR_W = host->cmd_va;
+ } else if (ctrl & NAND_ALE) {
+ this->IO_ADDR_R = host->addr_va;
+ this->IO_ADDR_W = host->addr_va;
+ } else {
+ this->IO_ADDR_R = host->data_va;
+ this->IO_ADDR_W = host->data_va;
+ }
+
+ pc = readl(FSMC_NAND_REG(regs, bank, PC));
+ if (ctrl & NAND_NCE)
+ pc |= FSMC_ENABLE;
+ else
+ pc &= ~FSMC_ENABLE;
+ writel_relaxed(pc, FSMC_NAND_REG(regs, bank, PC));
+ }
+
+ mb();
+
+ if (cmd != NAND_CMD_NONE)
+ writeb_relaxed(cmd, this->IO_ADDR_W);
+}
+
+/*
+ * fsmc_nand_setup - FSMC (Flexible Static Memory Controller) init routine
+ *
+ * This routine initializes timing parameters related to NAND memory access in
+ * FSMC registers
+ */
+static void fsmc_nand_setup(void __iomem *regs, uint32_t bank,
+ uint32_t busw, struct fsmc_nand_timings *timings)
+{
+ uint32_t value = FSMC_DEVTYPE_NAND | FSMC_ENABLE | FSMC_WAITON;
+ uint32_t tclr, tar, thiz, thold, twait, tset;
+ struct fsmc_nand_timings *tims;
+ struct fsmc_nand_timings default_timings = {
+ .tclr = FSMC_TCLR_1,
+ .tar = FSMC_TAR_1,
+ .thiz = FSMC_THIZ_1,
+ .thold = FSMC_THOLD_4,
+ .twait = FSMC_TWAIT_6,
+ .tset = FSMC_TSET_0,
+ };
+
+ if (timings)
+ tims = timings;
+ else
+ tims = &default_timings;
+
+ tclr = (tims->tclr & FSMC_TCLR_MASK) << FSMC_TCLR_SHIFT;
+ tar = (tims->tar & FSMC_TAR_MASK) << FSMC_TAR_SHIFT;
+ thiz = (tims->thiz & FSMC_THIZ_MASK) << FSMC_THIZ_SHIFT;
+ thold = (tims->thold & FSMC_THOLD_MASK) << FSMC_THOLD_SHIFT;
+ twait = (tims->twait & FSMC_TWAIT_MASK) << FSMC_TWAIT_SHIFT;
+ tset = (tims->tset & FSMC_TSET_MASK) << FSMC_TSET_SHIFT;
+
+ if (busw)
+ writel_relaxed(value | FSMC_DEVWID_16,
+ FSMC_NAND_REG(regs, bank, PC));
+ else
+ writel_relaxed(value | FSMC_DEVWID_8,
+ FSMC_NAND_REG(regs, bank, PC));
+
+ writel_relaxed(readl(FSMC_NAND_REG(regs, bank, PC)) | tclr | tar,
+ FSMC_NAND_REG(regs, bank, PC));
+ writel_relaxed(thiz | thold | twait | tset,
+ FSMC_NAND_REG(regs, bank, COMM));
+ writel_relaxed(thiz | thold | twait | tset,
+ FSMC_NAND_REG(regs, bank, ATTRIB));
+}
+
+/*
+ * fsmc_enable_hwecc - Enables Hardware ECC through FSMC registers
+ */
+static void fsmc_enable_hwecc(struct mtd_info *mtd, int mode)
+{
+ struct fsmc_nand_data *host = container_of(mtd,
+ struct fsmc_nand_data, mtd);
+ void __iomem *regs = host->regs_va;
+ uint32_t bank = host->bank;
+
+ writel_relaxed(readl(FSMC_NAND_REG(regs, bank, PC)) & ~FSMC_ECCPLEN_256,
+ FSMC_NAND_REG(regs, bank, PC));
+ writel_relaxed(readl(FSMC_NAND_REG(regs, bank, PC)) & ~FSMC_ECCEN,
+ FSMC_NAND_REG(regs, bank, PC));
+ writel_relaxed(readl(FSMC_NAND_REG(regs, bank, PC)) | FSMC_ECCEN,
+ FSMC_NAND_REG(regs, bank, PC));
+}
+
+/*
+ * fsmc_read_hwecc_ecc4 - Hardware ECC calculator for ecc4 option supported by
+ * FSMC. ECC is 13 bytes for 512 bytes of data (supports error correction up to
+ * max of 8-bits)
+ */
+static int fsmc_read_hwecc_ecc4(struct mtd_info *mtd, const uint8_t *data,
+ uint8_t *ecc)
+{
+ struct fsmc_nand_data *host = container_of(mtd,
+ struct fsmc_nand_data, mtd);
+ void __iomem *regs = host->regs_va;
+ uint32_t bank = host->bank;
+ uint32_t ecc_tmp;
+ unsigned long deadline = jiffies + FSMC_BUSY_WAIT_TIMEOUT;
+
+ do {
+ if (readl_relaxed(FSMC_NAND_REG(regs, bank, STS)) & FSMC_CODE_RDY)
+ break;
+ else
+ cond_resched();
+ } while (!time_after_eq(jiffies, deadline));
+
+ if (time_after_eq(jiffies, deadline)) {
+ dev_err(host->dev, "calculate ecc timed out\n");
+ return -ETIMEDOUT;
+ }
+
+ ecc_tmp = readl_relaxed(FSMC_NAND_REG(regs, bank, ECC1));
+ ecc[0] = (uint8_t) (ecc_tmp >> 0);
+ ecc[1] = (uint8_t) (ecc_tmp >> 8);
+ ecc[2] = (uint8_t) (ecc_tmp >> 16);
+ ecc[3] = (uint8_t) (ecc_tmp >> 24);
+
+ ecc_tmp = readl_relaxed(FSMC_NAND_REG(regs, bank, ECC2));
+ ecc[4] = (uint8_t) (ecc_tmp >> 0);
+ ecc[5] = (uint8_t) (ecc_tmp >> 8);
+ ecc[6] = (uint8_t) (ecc_tmp >> 16);
+ ecc[7] = (uint8_t) (ecc_tmp >> 24);
+
+ ecc_tmp = readl_relaxed(FSMC_NAND_REG(regs, bank, ECC3));
+ ecc[8] = (uint8_t) (ecc_tmp >> 0);
+ ecc[9] = (uint8_t) (ecc_tmp >> 8);
+ ecc[10] = (uint8_t) (ecc_tmp >> 16);
+ ecc[11] = (uint8_t) (ecc_tmp >> 24);
+
+ ecc_tmp = readl_relaxed(FSMC_NAND_REG(regs, bank, STS));
+ ecc[12] = (uint8_t) (ecc_tmp >> 16);
+
+ return 0;
+}
+
+/*
+ * fsmc_read_hwecc_ecc1 - Hardware ECC calculator for ecc1 option supported by
+ * FSMC. ECC is 3 bytes for 512 bytes of data (supports error correction up to
+ * max of 1-bit)
+ */
+static int fsmc_read_hwecc_ecc1(struct mtd_info *mtd, const uint8_t *data,
+ uint8_t *ecc)
+{
+ struct fsmc_nand_data *host = container_of(mtd,
+ struct fsmc_nand_data, mtd);
+ void __iomem *regs = host->regs_va;
+ uint32_t bank = host->bank;
+ uint32_t ecc_tmp;
+
+ ecc_tmp = readl_relaxed(FSMC_NAND_REG(regs, bank, ECC1));
+ ecc[0] = (uint8_t) (ecc_tmp >> 0);
+ ecc[1] = (uint8_t) (ecc_tmp >> 8);
+ ecc[2] = (uint8_t) (ecc_tmp >> 16);
+
+ return 0;
+}
+
+/* Count the number of 0's in buff upto a max of max_bits */
+static int count_written_bits(uint8_t *buff, int size, int max_bits)
+{
+ int k, written_bits = 0;
+
+ for (k = 0; k < size; k++) {
+ written_bits += hweight8(~buff[k]);
+ if (written_bits > max_bits)
+ break;
+ }
+
+ return written_bits;
+}
+
+static void dma_complete(void *param)
+{
+ struct fsmc_nand_data *host = param;
+
+ complete(&host->dma_access_complete);
+}
+
+static int dma_xfer(struct fsmc_nand_data *host, void *buffer, int len,
+ enum dma_data_direction direction)
+{
+ struct dma_chan *chan;
+ struct dma_device *dma_dev;
+ struct dma_async_tx_descriptor *tx;
+ dma_addr_t dma_dst, dma_src, dma_addr;
+ dma_cookie_t cookie;
+ unsigned long flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
+ int ret;
+
+ if (direction == DMA_TO_DEVICE)
+ chan = host->write_dma_chan;
+ else if (direction == DMA_FROM_DEVICE)
+ chan = host->read_dma_chan;
+ else
+ return -EINVAL;
+
+ dma_dev = chan->device;
+ dma_addr = dma_map_single(dma_dev->dev, buffer, len, direction);
+
+ if (direction == DMA_TO_DEVICE) {
+ dma_src = dma_addr;
+ dma_dst = host->data_pa;
+ } else {
+ dma_src = host->data_pa;
+ dma_dst = dma_addr;
+ }
+
+ tx = dma_dev->device_prep_dma_memcpy(chan, dma_dst, dma_src,
+ len, flags);
+ if (!tx) {
+ dev_err(host->dev, "device_prep_dma_memcpy error\n");
+ ret = -EIO;
+ goto unmap_dma;
+ }
+
+ tx->callback = dma_complete;
+ tx->callback_param = host;
+ cookie = tx->tx_submit(tx);
+
+ ret = dma_submit_error(cookie);
+ if (ret) {
+ dev_err(host->dev, "dma_submit_error %d\n", cookie);
+ goto unmap_dma;
+ }
+
+ dma_async_issue_pending(chan);
+
+ ret =
+ wait_for_completion_timeout(&host->dma_access_complete,
+ msecs_to_jiffies(3000));
+ if (ret <= 0) {
+ dmaengine_terminate_all(chan);
+ dev_err(host->dev, "wait_for_completion_timeout\n");
+ if (!ret)
+ ret = -ETIMEDOUT;
+ goto unmap_dma;
+ }
+
+ ret = 0;
+
+unmap_dma:
+ dma_unmap_single(dma_dev->dev, dma_addr, len, direction);
+
+ return ret;
+}
+
+/*
+ * fsmc_write_buf - write buffer to chip
+ * @mtd: MTD device structure
+ * @buf: data buffer
+ * @len: number of bytes to write
+ */
+static void fsmc_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+ int i;
+ struct nand_chip *chip = mtd->priv;
+
+ if (IS_ALIGNED((uint32_t)buf, sizeof(uint32_t)) &&
+ IS_ALIGNED(len, sizeof(uint32_t))) {
+ uint32_t *p = (uint32_t *)buf;
+ len = len >> 2;
+ for (i = 0; i < len; i++)
+ writel_relaxed(p[i], chip->IO_ADDR_W);
+ } else {
+ for (i = 0; i < len; i++)
+ writeb_relaxed(buf[i], chip->IO_ADDR_W);
+ }
+}
+
+/*
+ * fsmc_read_buf - read chip data into buffer
+ * @mtd: MTD device structure
+ * @buf: buffer to store date
+ * @len: number of bytes to read
+ */
+static void fsmc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+ int i;
+ struct nand_chip *chip = mtd->priv;
+
+ if (IS_ALIGNED((uint32_t)buf, sizeof(uint32_t)) &&
+ IS_ALIGNED(len, sizeof(uint32_t))) {
+ uint32_t *p = (uint32_t *)buf;
+ len = len >> 2;
+ for (i = 0; i < len; i++)
+ p[i] = readl_relaxed(chip->IO_ADDR_R);
+ } else {
+ for (i = 0; i < len; i++)
+ buf[i] = readb_relaxed(chip->IO_ADDR_R);
+ }
+}
+
+/*
+ * fsmc_read_buf_dma - read chip data into buffer
+ * @mtd: MTD device structure
+ * @buf: buffer to store date
+ * @len: number of bytes to read
+ */
+static void fsmc_read_buf_dma(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+ struct fsmc_nand_data *host;
+
+ host = container_of(mtd, struct fsmc_nand_data, mtd);
+ dma_xfer(host, buf, len, DMA_FROM_DEVICE);
+}
+
+/*
+ * fsmc_write_buf_dma - write buffer to chip
+ * @mtd: MTD device structure
+ * @buf: data buffer
+ * @len: number of bytes to write
+ */
+static void fsmc_write_buf_dma(struct mtd_info *mtd, const uint8_t *buf,
+ int len)
+{
+ struct fsmc_nand_data *host;
+
+ host = container_of(mtd, struct fsmc_nand_data, mtd);
+ dma_xfer(host, (void *)buf, len, DMA_TO_DEVICE);
+}
+
+/*
+ * fsmc_read_page_hwecc
+ * @mtd: mtd info structure
+ * @chip: nand chip info structure
+ * @buf: buffer to store read data
+ * @oob_required: caller expects OOB data read to chip->oob_poi
+ * @page: page number to read
+ *
+ * This routine is needed for fsmc version 8 as reading from NAND chip has to be
+ * performed in a strict sequence as follows:
+ * data(512 byte) -> ecc(13 byte)
+ * After this read, fsmc hardware generates and reports error data bits(up to a
+ * max of 8 bits)
+ */
+static int fsmc_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
+ uint8_t *buf, int oob_required, int page)
+{
+ struct fsmc_nand_data *host = container_of(mtd,
+ struct fsmc_nand_data, mtd);
+ struct fsmc_eccplace *ecc_place = host->ecc_place;
+ int i, j, s, stat, eccsize = chip->ecc.size;
+ int eccbytes = chip->ecc.bytes;
+ int eccsteps = chip->ecc.steps;
+ uint8_t *p = buf;
+ uint8_t *ecc_calc = chip->buffers->ecccalc;
+ uint8_t *ecc_code = chip->buffers->ecccode;
+ int off, len, group = 0;
+ /*
+ * ecc_oob is intentionally taken as uint16_t. In 16bit devices, we
+ * end up reading 14 bytes (7 words) from oob. The local array is
+ * to maintain word alignment
+ */
+ uint16_t ecc_oob[7];
+ uint8_t *oob = (uint8_t *)&ecc_oob[0];
+ unsigned int max_bitflips = 0;
+
+ for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, p += eccsize) {
+ chip->cmdfunc(mtd, NAND_CMD_READ0, s * eccsize, page);
+ chip->ecc.hwctl(mtd, NAND_ECC_READ);
+ chip->read_buf(mtd, p, eccsize);
+
+ for (j = 0; j < eccbytes;) {
+ off = ecc_place->eccplace[group].offset;
+ len = ecc_place->eccplace[group].length;
+ group++;
+
+ /*
+ * length is intentionally kept a higher multiple of 2
+ * to read at least 13 bytes even in case of 16 bit NAND
+ * devices
+ */
+ if (chip->options & NAND_BUSWIDTH_16)
+ len = roundup(len, 2);
+
+ chip->cmdfunc(mtd, NAND_CMD_READOOB, off, page);
+ chip->read_buf(mtd, oob + j, len);
+ j += len;
+ }
+
+ memcpy(&ecc_code[i], oob, chip->ecc.bytes);
+ chip->ecc.calculate(mtd, p, &ecc_calc[i]);
+
+ stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
+ if (stat < 0) {
+ mtd->ecc_stats.failed++;
+ } else {
+ mtd->ecc_stats.corrected += stat;
+ max_bitflips = max_t(unsigned int, max_bitflips, stat);
+ }
+ }
+
+ return max_bitflips;
+}
+
+/*
+ * fsmc_bch8_correct_data
+ * @mtd: mtd info structure
+ * @dat: buffer of read data
+ * @read_ecc: ecc read from device spare area
+ * @calc_ecc: ecc calculated from read data
+ *
+ * calc_ecc is a 104 bit information containing maximum of 8 error
+ * offset informations of 13 bits each in 512 bytes of read data.
+ */
+static int fsmc_bch8_correct_data(struct mtd_info *mtd, uint8_t *dat,
+ uint8_t *read_ecc, uint8_t *calc_ecc)
+{
+ struct fsmc_nand_data *host = container_of(mtd,
+ struct fsmc_nand_data, mtd);
+ struct nand_chip *chip = mtd->priv;
+ void __iomem *regs = host->regs_va;
+ unsigned int bank = host->bank;
+ uint32_t err_idx[8];
+ uint32_t num_err, i;
+ uint32_t ecc1, ecc2, ecc3, ecc4;
+
+ num_err = (readl_relaxed(FSMC_NAND_REG(regs, bank, STS)) >> 10) & 0xF;
+
+ /* no bit flipping */
+ if (likely(num_err == 0))
+ return 0;
+
+ /* too many errors */
+ if (unlikely(num_err > 8)) {
+ /*
+ * This is a temporary erase check. A newly erased page read
+ * would result in an ecc error because the oob data is also
+ * erased to FF and the calculated ecc for an FF data is not
+ * FF..FF.
+ * This is a workaround to skip performing correction in case
+ * data is FF..FF
+ *
+ * Logic:
+ * For every page, each bit written as 0 is counted until these
+ * number of bits are greater than 8 (the maximum correction
+ * capability of FSMC for each 512 + 13 bytes)
+ */
+
+ int bits_ecc = count_written_bits(read_ecc, chip->ecc.bytes, 8);
+ int bits_data = count_written_bits(dat, chip->ecc.size, 8);
+
+ if ((bits_ecc + bits_data) <= 8) {
+ if (bits_data)
+ memset(dat, 0xff, chip->ecc.size);
+ return bits_data;
+ }
+
+ return -EBADMSG;
+ }
+
+ /*
+ * ------------------- calc_ecc[] bit wise -----------|--13 bits--|
+ * |---idx[7]--|--.....-----|---idx[2]--||---idx[1]--||---idx[0]--|
+ *
+ * calc_ecc is a 104 bit information containing maximum of 8 error
+ * offset informations of 13 bits each. calc_ecc is copied into a
+ * uint64_t array and error offset indexes are populated in err_idx
+ * array
+ */
+ ecc1 = readl_relaxed(FSMC_NAND_REG(regs, bank, ECC1));
+ ecc2 = readl_relaxed(FSMC_NAND_REG(regs, bank, ECC2));
+ ecc3 = readl_relaxed(FSMC_NAND_REG(regs, bank, ECC3));
+ ecc4 = readl_relaxed(FSMC_NAND_REG(regs, bank, STS));
+
+ err_idx[0] = (ecc1 >> 0) & 0x1FFF;
+ err_idx[1] = (ecc1 >> 13) & 0x1FFF;
+ err_idx[2] = (((ecc2 >> 0) & 0x7F) << 6) | ((ecc1 >> 26) & 0x3F);
+ err_idx[3] = (ecc2 >> 7) & 0x1FFF;
+ err_idx[4] = (((ecc3 >> 0) & 0x1) << 12) | ((ecc2 >> 20) & 0xFFF);
+ err_idx[5] = (ecc3 >> 1) & 0x1FFF;
+ err_idx[6] = (ecc3 >> 14) & 0x1FFF;
+ err_idx[7] = (((ecc4 >> 16) & 0xFF) << 5) | ((ecc3 >> 27) & 0x1F);
+
+ i = 0;
+ while (num_err--) {
+ change_bit(0, (unsigned long *)&err_idx[i]);
+ change_bit(1, (unsigned long *)&err_idx[i]);
+
+ if (err_idx[i] < chip->ecc.size * 8) {
+ change_bit(err_idx[i], (unsigned long *)dat);
+ i++;
+ }
+ }
+ return i;
+}
+
+static bool filter(struct dma_chan *chan, void *slave)
+{
+ chan->private = slave;
+ return true;
+}
+
+#ifdef CONFIG_OF
+static int fsmc_nand_probe_config_dt(struct platform_device *pdev,
+ struct device_node *np)
+{
+ struct fsmc_nand_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ u32 val;
+ int ret;
+
+ /* Set default NAND width to 8 bits */
+ pdata->width = 8;
+ if (!of_property_read_u32(np, "bank-width", &val)) {
+ if (val == 2) {
+ pdata->width = 16;
+ } else if (val != 1) {
+ dev_err(&pdev->dev, "invalid bank-width %u\n", val);
+ return -EINVAL;
+ }
+ }
+ if (of_get_property(np, "nand-skip-bbtscan", NULL))
+ pdata->options = NAND_SKIP_BBTSCAN;
+
+ pdata->nand_timings = devm_kzalloc(&pdev->dev,
+ sizeof(*pdata->nand_timings), GFP_KERNEL);
+ if (!pdata->nand_timings)
+ return -ENOMEM;
+ ret = of_property_read_u8_array(np, "timings", (u8 *)pdata->nand_timings,
+ sizeof(*pdata->nand_timings));
+ if (ret) {
+ dev_info(&pdev->dev, "No timings in dts specified, using default timings!\n");
+ pdata->nand_timings = NULL;
+ }
+
+ /* Set default NAND bank to 0 */
+ pdata->bank = 0;
+ if (!of_property_read_u32(np, "bank", &val)) {
+ if (val > 3) {
+ dev_err(&pdev->dev, "invalid bank %u\n", val);
+ return -EINVAL;
+ }
+ pdata->bank = val;
+ }
+ return 0;
+}
+#else
+static int fsmc_nand_probe_config_dt(struct platform_device *pdev,
+ struct device_node *np)
+{
+ return -ENOSYS;
+}
+#endif
+
+/*
+ * fsmc_nand_probe - Probe function
+ * @pdev: platform device structure
+ */
+static int __init fsmc_nand_probe(struct platform_device *pdev)
+{
+ struct fsmc_nand_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ struct device_node __maybe_unused *np = pdev->dev.of_node;
+ struct mtd_part_parser_data ppdata = {};
+ struct fsmc_nand_data *host;
+ struct mtd_info *mtd;
+ struct nand_chip *nand;
+ struct resource *res;
+ dma_cap_mask_t mask;
+ int ret = 0;
+ u32 pid;
+ int i;
+
+ if (np) {
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ pdev->dev.platform_data = pdata;
+ ret = fsmc_nand_probe_config_dt(pdev, np);
+ if (ret) {
+ dev_err(&pdev->dev, "no platform data\n");
+ return -ENODEV;
+ }
+ }
+
+ if (!pdata) {
+ dev_err(&pdev->dev, "platform data is NULL\n");
+ return -EINVAL;
+ }
+
+ /* Allocate memory for the device structure (and zero it) */
+ host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
+ if (!host)
+ return -ENOMEM;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_data");
+ host->data_va = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(host->data_va))
+ return PTR_ERR(host->data_va);
+
+ host->data_pa = (dma_addr_t)res->start;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_addr");
+ host->addr_va = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(host->addr_va))
+ return PTR_ERR(host->addr_va);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_cmd");
+ host->cmd_va = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(host->cmd_va))
+ return PTR_ERR(host->cmd_va);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fsmc_regs");
+ host->regs_va = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(host->regs_va))
+ return PTR_ERR(host->regs_va);
+
+ host->clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(host->clk)) {
+ dev_err(&pdev->dev, "failed to fetch block clock\n");
+ return PTR_ERR(host->clk);
+ }
+
+ ret = clk_prepare_enable(host->clk);
+ if (ret)
+ goto err_clk_prepare_enable;
+
+ /*
+ * This device ID is actually a common AMBA ID as used on the
+ * AMBA PrimeCell bus. However it is not a PrimeCell.
+ */
+ for (pid = 0, i = 0; i < 4; i++)
+ pid |= (readl(host->regs_va + resource_size(res) - 0x20 + 4 * i) & 255) << (i * 8);
+ host->pid = pid;
+ dev_info(&pdev->dev, "FSMC device partno %03x, manufacturer %02x, "
+ "revision %02x, config %02x\n",
+ AMBA_PART_BITS(pid), AMBA_MANF_BITS(pid),
+ AMBA_REV_BITS(pid), AMBA_CONFIG_BITS(pid));
+
+ host->bank = pdata->bank;
+ host->select_chip = pdata->select_bank;
+ host->partitions = pdata->partitions;
+ host->nr_partitions = pdata->nr_partitions;
+ host->dev = &pdev->dev;
+ host->dev_timings = pdata->nand_timings;
+ host->mode = pdata->mode;
+
+ if (host->mode == USE_DMA_ACCESS)
+ init_completion(&host->dma_access_complete);
+
+ /* Link all private pointers */
+ mtd = &host->mtd;
+ nand = &host->nand;
+ mtd->priv = nand;
+ nand->priv = host;
+
+ host->mtd.owner = THIS_MODULE;
+ nand->IO_ADDR_R = host->data_va;
+ nand->IO_ADDR_W = host->data_va;
+ nand->cmd_ctrl = fsmc_cmd_ctrl;
+ nand->chip_delay = 30;
+
+ nand->ecc.mode = NAND_ECC_HW;
+ nand->ecc.hwctl = fsmc_enable_hwecc;
+ nand->ecc.size = 512;
+ nand->options = pdata->options;
+ nand->select_chip = fsmc_select_chip;
+ nand->badblockbits = 7;
+
+ if (pdata->width == FSMC_NAND_BW16)
+ nand->options |= NAND_BUSWIDTH_16;
+
+ switch (host->mode) {
+ case USE_DMA_ACCESS:
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_MEMCPY, mask);
+ host->read_dma_chan = dma_request_channel(mask, filter,
+ pdata->read_dma_priv);
+ if (!host->read_dma_chan) {
+ dev_err(&pdev->dev, "Unable to get read dma channel\n");
+ goto err_req_read_chnl;
+ }
+ host->write_dma_chan = dma_request_channel(mask, filter,
+ pdata->write_dma_priv);
+ if (!host->write_dma_chan) {
+ dev_err(&pdev->dev, "Unable to get write dma channel\n");
+ goto err_req_write_chnl;
+ }
+ nand->read_buf = fsmc_read_buf_dma;
+ nand->write_buf = fsmc_write_buf_dma;
+ break;
+
+ default:
+ case USE_WORD_ACCESS:
+ nand->read_buf = fsmc_read_buf;
+ nand->write_buf = fsmc_write_buf;
+ break;
+ }
+
+ fsmc_nand_setup(host->regs_va, host->bank,
+ nand->options & NAND_BUSWIDTH_16,
+ host->dev_timings);
+
+ if (AMBA_REV_BITS(host->pid) >= 8) {
+ nand->ecc.read_page = fsmc_read_page_hwecc;
+ nand->ecc.calculate = fsmc_read_hwecc_ecc4;
+ nand->ecc.correct = fsmc_bch8_correct_data;
+ nand->ecc.bytes = 13;
+ nand->ecc.strength = 8;
+ } else {
+ nand->ecc.calculate = fsmc_read_hwecc_ecc1;
+ nand->ecc.correct = nand_correct_data;
+ nand->ecc.bytes = 3;
+ nand->ecc.strength = 1;
+ }
+
+ /*
+ * Scan to find existence of the device
+ */
+ if (nand_scan_ident(&host->mtd, 1, NULL)) {
+ ret = -ENXIO;
+ dev_err(&pdev->dev, "No NAND Device found!\n");
+ goto err_scan_ident;
+ }
+
+ if (AMBA_REV_BITS(host->pid) >= 8) {
+ switch (host->mtd.oobsize) {
+ case 16:
+ nand->ecc.layout = &fsmc_ecc4_16_layout;
+ host->ecc_place = &fsmc_ecc4_sp_place;
+ break;
+ case 64:
+ nand->ecc.layout = &fsmc_ecc4_64_layout;
+ host->ecc_place = &fsmc_ecc4_lp_place;
+ break;
+ case 128:
+ nand->ecc.layout = &fsmc_ecc4_128_layout;
+ host->ecc_place = &fsmc_ecc4_lp_place;
+ break;
+ case 224:
+ nand->ecc.layout = &fsmc_ecc4_224_layout;
+ host->ecc_place = &fsmc_ecc4_lp_place;
+ break;
+ case 256:
+ nand->ecc.layout = &fsmc_ecc4_256_layout;
+ host->ecc_place = &fsmc_ecc4_lp_place;
+ break;
+ default:
+ dev_warn(&pdev->dev, "No oob scheme defined for oobsize %d\n",
+ mtd->oobsize);
+ BUG();
+ }
+ } else {
+ switch (host->mtd.oobsize) {
+ case 16:
+ nand->ecc.layout = &fsmc_ecc1_16_layout;
+ break;
+ case 64:
+ nand->ecc.layout = &fsmc_ecc1_64_layout;
+ break;
+ case 128:
+ nand->ecc.layout = &fsmc_ecc1_128_layout;
+ break;
+ default:
+ dev_warn(&pdev->dev, "No oob scheme defined for oobsize %d\n",
+ mtd->oobsize);
+ BUG();
+ }
+ }
+
+ /* Second stage of scan to fill MTD data-structures */
+ if (nand_scan_tail(&host->mtd)) {
+ ret = -ENXIO;
+ goto err_probe;
+ }
+
+ /*
+ * The partition information can is accessed by (in the same precedence)
+ *
+ * command line through Bootloader,
+ * platform data,
+ * default partition information present in driver.
+ */
+ /*
+ * Check for partition info passed
+ */
+ host->mtd.name = "nand";
+ ppdata.of_node = np;
+ ret = mtd_device_parse_register(&host->mtd, NULL, &ppdata,
+ host->partitions, host->nr_partitions);
+ if (ret)
+ goto err_probe;
+
+ platform_set_drvdata(pdev, host);
+ dev_info(&pdev->dev, "FSMC NAND driver registration successful\n");
+ return 0;
+
+err_probe:
+err_scan_ident:
+ if (host->mode == USE_DMA_ACCESS)
+ dma_release_channel(host->write_dma_chan);
+err_req_write_chnl:
+ if (host->mode == USE_DMA_ACCESS)
+ dma_release_channel(host->read_dma_chan);
+err_req_read_chnl:
+ clk_disable_unprepare(host->clk);
+err_clk_prepare_enable:
+ clk_put(host->clk);
+ return ret;
+}
+
+/*
+ * Clean up routine
+ */
+static int fsmc_nand_remove(struct platform_device *pdev)
+{
+ struct fsmc_nand_data *host = platform_get_drvdata(pdev);
+
+ if (host) {
+ nand_release(&host->mtd);
+
+ if (host->mode == USE_DMA_ACCESS) {
+ dma_release_channel(host->write_dma_chan);
+ dma_release_channel(host->read_dma_chan);
+ }
+ clk_disable_unprepare(host->clk);
+ clk_put(host->clk);
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int fsmc_nand_suspend(struct device *dev)
+{
+ struct fsmc_nand_data *host = dev_get_drvdata(dev);
+ if (host)
+ clk_disable_unprepare(host->clk);
+ return 0;
+}
+
+static int fsmc_nand_resume(struct device *dev)
+{
+ struct fsmc_nand_data *host = dev_get_drvdata(dev);
+ if (host) {
+ clk_prepare_enable(host->clk);
+ fsmc_nand_setup(host->regs_va, host->bank,
+ host->nand.options & NAND_BUSWIDTH_16,
+ host->dev_timings);
+ }
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(fsmc_nand_pm_ops, fsmc_nand_suspend, fsmc_nand_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id fsmc_nand_id_table[] = {
+ { .compatible = "st,spear600-fsmc-nand" },
+ { .compatible = "stericsson,fsmc-nand" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, fsmc_nand_id_table);
+#endif
+
+static struct platform_driver fsmc_nand_driver = {
+ .remove = fsmc_nand_remove,
+ .driver = {
+ .name = "fsmc-nand",
+ .of_match_table = of_match_ptr(fsmc_nand_id_table),
+ .pm = &fsmc_nand_pm_ops,
+ },
+};
+
+module_platform_driver_probe(fsmc_nand_driver, fsmc_nand_probe);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>, Ashish Priyadarshi");
+MODULE_DESCRIPTION("NAND driver for SPEAr Platforms");