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Diffstat (limited to 'drivers/mtd/nand/ams-delta.c')
-rw-r--r--drivers/mtd/nand/ams-delta.c237
1 files changed, 237 insertions, 0 deletions
diff --git a/drivers/mtd/nand/ams-delta.c b/drivers/mtd/nand/ams-delta.c
new file mode 100644
index 00000000000..d7897dc6b3c
--- /dev/null
+++ b/drivers/mtd/nand/ams-delta.c
@@ -0,0 +1,237 @@
+/*
+ * drivers/mtd/nand/ams-delta.c
+ *
+ * Copyright (C) 2006 Jonathan McDowell <noodles@earth.li>
+ *
+ * Derived from drivers/mtd/toto.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Overview:
+ * This is a device driver for the NAND flash device found on the
+ * Amstrad E3 (Delta).
+ */
+
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/sizes.h>
+#include <asm/arch/gpio.h>
+#include <asm/arch/board-ams-delta.h>
+
+/*
+ * MTD structure for E3 (Delta)
+ */
+static struct mtd_info *ams_delta_mtd = NULL;
+
+#define NAND_MASK (AMS_DELTA_LATCH2_NAND_NRE | AMS_DELTA_LATCH2_NAND_NWE | AMS_DELTA_LATCH2_NAND_CLE | AMS_DELTA_LATCH2_NAND_ALE | AMS_DELTA_LATCH2_NAND_NCE | AMS_DELTA_LATCH2_NAND_NWP)
+
+/*
+ * Define partitions for flash devices
+ */
+
+static struct mtd_partition partition_info[] = {
+ { .name = "Kernel",
+ .offset = 0,
+ .size = 3 * SZ_1M + SZ_512K },
+ { .name = "u-boot",
+ .offset = 3 * SZ_1M + SZ_512K,
+ .size = SZ_256K },
+ { .name = "u-boot params",
+ .offset = 3 * SZ_1M + SZ_512K + SZ_256K,
+ .size = SZ_256K },
+ { .name = "Amstrad LDR",
+ .offset = 4 * SZ_1M,
+ .size = SZ_256K },
+ { .name = "File system",
+ .offset = 4 * SZ_1M + 1 * SZ_256K,
+ .size = 27 * SZ_1M },
+ { .name = "PBL reserved",
+ .offset = 32 * SZ_1M - 3 * SZ_256K,
+ .size = 3 * SZ_256K },
+};
+
+static void ams_delta_write_byte(struct mtd_info *mtd, u_char byte)
+{
+ struct nand_chip *this = mtd->priv;
+
+ omap_writew(0, (OMAP_MPUIO_BASE + OMAP_MPUIO_IO_CNTL));
+ omap_writew(byte, this->IO_ADDR_W);
+ ams_delta_latch2_write(AMS_DELTA_LATCH2_NAND_NWE, 0);
+ ndelay(40);
+ ams_delta_latch2_write(AMS_DELTA_LATCH2_NAND_NWE,
+ AMS_DELTA_LATCH2_NAND_NWE);
+}
+
+static u_char ams_delta_read_byte(struct mtd_info *mtd)
+{
+ u_char res;
+ struct nand_chip *this = mtd->priv;
+
+ ams_delta_latch2_write(AMS_DELTA_LATCH2_NAND_NRE, 0);
+ ndelay(40);
+ omap_writew(~0, (OMAP_MPUIO_BASE + OMAP_MPUIO_IO_CNTL));
+ res = omap_readw(this->IO_ADDR_R);
+ ams_delta_latch2_write(AMS_DELTA_LATCH2_NAND_NRE,
+ AMS_DELTA_LATCH2_NAND_NRE);
+
+ return res;
+}
+
+static void ams_delta_write_buf(struct mtd_info *mtd, const u_char *buf,
+ int len)
+{
+ int i;
+
+ for (i=0; i<len; i++)
+ ams_delta_write_byte(mtd, buf[i]);
+}
+
+static void ams_delta_read_buf(struct mtd_info *mtd, u_char *buf, int len)
+{
+ int i;
+
+ for (i=0; i<len; i++)
+ buf[i] = ams_delta_read_byte(mtd);
+}
+
+static int ams_delta_verify_buf(struct mtd_info *mtd, const u_char *buf,
+ int len)
+{
+ int i;
+
+ for (i=0; i<len; i++)
+ if (buf[i] != ams_delta_read_byte(mtd))
+ return -EFAULT;
+
+ return 0;
+}
+
+/*
+ * Command control function
+ *
+ * ctrl:
+ * NAND_NCE: bit 0 -> bit 2
+ * NAND_CLE: bit 1 -> bit 7
+ * NAND_ALE: bit 2 -> bit 6
+ */
+static void ams_delta_hwcontrol(struct mtd_info *mtd, int cmd,
+ unsigned int ctrl)
+{
+
+ if (ctrl & NAND_CTRL_CHANGE) {
+ unsigned long bits;
+
+ bits = (~ctrl & NAND_NCE) << 2;
+ bits |= (ctrl & NAND_CLE) << 7;
+ bits |= (ctrl & NAND_ALE) << 6;
+
+ ams_delta_latch2_write(0xC2, bits);
+ }
+
+ if (cmd != NAND_CMD_NONE)
+ ams_delta_write_byte(mtd, cmd);
+}
+
+static int ams_delta_nand_ready(struct mtd_info *mtd)
+{
+ return omap_get_gpio_datain(AMS_DELTA_GPIO_PIN_NAND_RB);
+}
+
+/*
+ * Main initialization routine
+ */
+static int __init ams_delta_init(void)
+{
+ struct nand_chip *this;
+ int err = 0;
+
+ /* Allocate memory for MTD device structure and private data */
+ ams_delta_mtd = kmalloc(sizeof(struct mtd_info) +
+ sizeof(struct nand_chip), GFP_KERNEL);
+ if (!ams_delta_mtd) {
+ printk (KERN_WARNING "Unable to allocate E3 NAND MTD device structure.\n");
+ err = -ENOMEM;
+ goto out;
+ }
+
+ ams_delta_mtd->owner = THIS_MODULE;
+
+ /* Get pointer to private data */
+ this = (struct nand_chip *) (&ams_delta_mtd[1]);
+
+ /* Initialize structures */
+ memset(ams_delta_mtd, 0, sizeof(struct mtd_info));
+ memset(this, 0, sizeof(struct nand_chip));
+
+ /* Link the private data with the MTD structure */
+ ams_delta_mtd->priv = this;
+
+ /* Set address of NAND IO lines */
+ this->IO_ADDR_R = (OMAP_MPUIO_BASE + OMAP_MPUIO_INPUT_LATCH);
+ this->IO_ADDR_W = (OMAP_MPUIO_BASE + OMAP_MPUIO_OUTPUT);
+ this->read_byte = ams_delta_read_byte;
+ this->write_buf = ams_delta_write_buf;
+ this->read_buf = ams_delta_read_buf;
+ this->verify_buf = ams_delta_verify_buf;
+ this->cmd_ctrl = ams_delta_hwcontrol;
+ if (!omap_request_gpio(AMS_DELTA_GPIO_PIN_NAND_RB)) {
+ this->dev_ready = ams_delta_nand_ready;
+ } else {
+ this->dev_ready = NULL;
+ printk(KERN_NOTICE "Couldn't request gpio for Delta NAND ready.\n");
+ }
+ /* 25 us command delay time */
+ this->chip_delay = 30;
+ this->ecc.mode = NAND_ECC_SOFT;
+
+ /* Set chip enabled, but */
+ ams_delta_latch2_write(NAND_MASK, AMS_DELTA_LATCH2_NAND_NRE |
+ AMS_DELTA_LATCH2_NAND_NWE |
+ AMS_DELTA_LATCH2_NAND_NCE |
+ AMS_DELTA_LATCH2_NAND_NWP);
+
+ /* Scan to find existance of the device */
+ if (nand_scan(ams_delta_mtd, 1)) {
+ err = -ENXIO;
+ goto out_mtd;
+ }
+
+ /* Register the partitions */
+ add_mtd_partitions(ams_delta_mtd, partition_info,
+ ARRAY_SIZE(partition_info));
+
+ goto out;
+
+ out_mtd:
+ kfree(ams_delta_mtd);
+ out:
+ return err;
+}
+
+module_init(ams_delta_init);
+
+/*
+ * Clean up routine
+ */
+static void __exit ams_delta_cleanup(void)
+{
+ /* Release resources, unregister device */
+ nand_release(ams_delta_mtd);
+
+ /* Free the MTD device structure */
+ kfree(ams_delta_mtd);
+}
+module_exit(ams_delta_cleanup);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jonathan McDowell <noodles@earth.li>");
+MODULE_DESCRIPTION("Glue layer for NAND flash on Amstrad E3 (Delta)");