[PATCH] NAND Flash support for Intel IXP4xx platform
Ruslan V. Sushko
rsushko at ru.mvista.com
Tue Apr 24 06:33:40 EDT 2007
The patch adds glue logic to support MTD for NAND flash devices on Intel
IXP4xx based platform
The patch made against the 2.6.21-rc4 kernel
Updated after Vitaly's comments
Signed-off-by: rsushko at ru.mvista.com <http://lists.infradead.org/mailman/listinfo/linux-mtd>
Index: linux-2.6/drivers/mtd/nand/Kconfig
===================================================================
--- linux-2.6.orig/drivers/mtd/nand/Kconfig
+++ linux-2.6/drivers/mtd/nand/Kconfig
@@ -143,6 +143,13 @@ config MTD_NAND_S3C2410_CLKSTOP
when the is NAND chip selected or released, but will save
approximately 5mA of power when there is nothing happening.
+config MTD_NAND_IXP4XX
+ tristate "Support for NAND Flash on Intel IXP4XX based systems"
+ depends on MTD_NAND && ARCH_IXP4XX
+ help
+ This enable the use of NAND flash on Intel IXP400 based platforms.
+ Currently this is only supported on KIXRP435 platform.
+
config MTD_NAND_DISKONCHIP
tristate "DiskOnChip 2000, Millennium and Millennium Plus (NAND
reimplementation) (EXPERIMENTAL)"
depends on MTD_NAND && EXPERIMENTAL
Index: linux-2.6/drivers/mtd/nand/Makefile
===================================================================
--- linux-2.6.orig/drivers/mtd/nand/Makefile
+++ linux-2.6/drivers/mtd/nand/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_MTD_NAND_CS553X) += cs553x
obj-$(CONFIG_MTD_NAND_NDFC) += ndfc.o
obj-$(CONFIG_MTD_NAND_AT91) += at91_nand.o
obj-$(CONFIG_MTD_NAND_BASLER_EXCITE) += excite_nandflash.o
+obj-$(CONFIG_MTD_NAND_IXP4XX) += ixp4xx_nand.o
nand-objs := nand_base.o nand_bbt.o
cafe_nand-objs := cafe.o cafe_ecc.o
Index: linux-2.6/drivers/mtd/nand/ixp4xx_nand.c
===================================================================
--- /dev/null
+++ linux-2.6/drivers/mtd/nand/ixp4xx_nand.c
@@ -0,0 +1,221 @@
+/*
+ * drivers/mtd/nand/ixp4xx_nand.c
+ *
+ * Copyright (C) 2006 Intel Corporation.
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+
+#include <asm/io.h>
+#include <asm/arch/nand.h>
+#include <asm/hardware.h>
+#include <asm/delay.h>
+
+/*
+ * MTD structure for NAND controller
+ */
+static struct mtd_info *ixp4xx_mtd = NULL;
+static struct mtd_partition *ixp4xx_nand_parts = NULL;
+const char *part_probes[] = { "cmdlinepart", NULL };
+
+static struct ixp4xx_faddr_info_t {
+ int offset;
+ void (*chip_select)(unsigned int ctrl);
+} ixp4xx_faddr_info;
+
+/**
+ * ixp_write_buf - write buffer to chip
+ * @mtd: MTD device structure
+ * @buf: data buffer
+ * @len: number of bytes to write
+ *
+ * write function for 8bit buswith
+ */
+static void
+ixp_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
+{
+ int i;
+ struct nand_chip *this = mtd->priv;
+
+ for ( i = 0 ; i < len ; i++ )
+ writeb(buf[i], this->IO_ADDR_W);
+}
+
+static void
+ixp4xx_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
+{
+ struct nand_chip *this = mtd->priv;
+ struct ixp4xx_faddr_info_t *addr_info = this->priv;
+ if (ctrl & NAND_CTRL_CHANGE) {
+ addr_info->offset = (ctrl & NAND_CLE) ? IXP4XX_NAND_CLE : 0;
+ addr_info->offset |= (ctrl & NAND_ALE) ? IXP4XX_NAND_ALE : 0;
+ if (addr_info->chip_select)
+ addr_info->chip_select(ctrl);
+ }
+
+ if (cmd != NAND_CMD_NONE)
+ writeb(cmd, this->IO_ADDR_W + addr_info->offset);
+}
+
+static int
+ixp4xx_nand_flash_probe(struct platform_device *dev)
+{
+ int err;
+ int nb_of_parts;
+ struct nand_chip *this;
+ void __iomem *nand_io_base;
+ struct ixp4xx_nand_platform_data *plat = dev->dev.platform_data;
+
+ if (!plat)
+ return -ENODEV;
+
+ if (plat->width != 1) {
+ printk(KERN_ERR "%s: %d bits bus width is not support for "
+ "ixp4xx driver\n", __FUNCTION__, plat->width * 8);
+ return -EINVAL;
+ }
+
+ if (plat->init) {
+ err = plat->init();
+ if (err)
+ return err;
+ }
+
+ /* Allocate memory for MTD device structure and private data */
+ ixp4xx_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct
nand_chip),
+ GFP_KERNEL);
+
+ if (ixp4xx_mtd == NULL) {
+ printk (KERN_ERR "Fail on mem alloc for NAND MTD dev\n");
+ return -ENOMEM;
+ }
+
+ /* Initialize structures and build the linkage to private data */
+ memset(ixp4xx_mtd, 0, sizeof(struct mtd_info)+sizeof(struct
nand_chip));
+ this = (struct nand_chip *)(&ixp4xx_mtd[1]);
+
+ ixp4xx_mtd->priv = this;
+
+ ixp4xx_mtd->owner = THIS_MODULE;
+ ixp4xx_mtd->name = "ixp4xx-nand";
+
+ /* ioremap the io of NAND Flash */
+ nand_io_base = ioremap(dev->resource->start,
+ dev->resource->end - dev->resource->start + 1);
+ if (!nand_io_base) {
+ printk (KERN_ERR "Unable to map nand flash IO space\n");
+ err = -EIO;
+ goto error;
+ }
+
+ ixp4xx_faddr_info.offset = 0;
+ ixp4xx_faddr_info.chip_select = plat->chip_select;
+
+ /* Set address of hardware control function */
+ this->cmd_ctrl = ixp4xx_hwcontrol;
+ this->dev_ready = NULL;/* KIXRP435 has no GPIO pins route to R/B */
+ this->chip_delay = 30; /* 30 us command delay time */
+ this->ecc.mode = NAND_ECC_SOFT;
+ this->options = NAND_NO_AUTOINCR;
+ this->IO_ADDR_R = nand_io_base;
+ this->IO_ADDR_W = nand_io_base;
+ this->priv = &ixp4xx_faddr_info;
+ this->write_buf = ixp_write_buf;
+
+ /* Scan to find existence of the device */
+ if (nand_scan(ixp4xx_mtd, 1)) {
+ err = -ENXIO;
+ goto error;
+ }
+
+ nb_of_parts = parse_mtd_partitions(ixp4xx_mtd, part_probes,
+ &ixp4xx_nand_parts, 0);
+
+ if (nb_of_parts <= 0) { /* No partition from parsing, use default */
+ printk(KERN_INFO "Loading default partition table\n");
+ ixp4xx_nand_parts = plat->parts;
+ nb_of_parts = plat->nr_parts;
+ }
+
+ /* Register the partitions */
+ err = add_mtd_partitions(ixp4xx_mtd, ixp4xx_nand_parts, nb_of_parts);
+ if (err) {
+ printk(KERN_ERR "Failed to add MTD partitions\n");
+ if(ixp4xx_nand_parts != plat->parts)
+ kfree(ixp4xx_nand_parts);
+ goto error;
+ }
+ return 0;
+
+error:
+ if (nand_io_base)
+ iounmap ((void *)nand_io_base);
+
+ if(ixp4xx_mtd)
+ kfree (ixp4xx_mtd);
+ return err;
+}
+
+static int
+ixp4xx_nand_flash_remove(struct platform_device *dev)
+{
+ struct ixp4xx_nand_platform_data *plat = dev->dev.platform_data;
+ struct nand_chip *this = (struct nand_chip *)&ixp4xx_mtd[1];
+
+ if (plat->exit)
+ plat->exit();
+
+ /* Unmap IO */
+ iounmap((void *)this->IO_ADDR_W);
+
+ /* Release resources, unregister device */
+ nand_release(ixp4xx_mtd);
+
+ /* Free the MTD device structure */
+ kfree(ixp4xx_mtd);
+
+ /* Free the parsed partition table */
+ if (ixp4xx_nand_parts != plat->parts)
+ kfree(ixp4xx_nand_parts);
+ return 0;
+}
+
+static struct platform_driver ixp4xx_nand_flash_driver = {
+ .probe = ixp4xx_nand_flash_probe,
+ .remove = ixp4xx_nand_flash_remove,
+ .driver = {
+ .name = "IXP4XX-NAND-Flash",
+ },
+};
+
+static int __init ixp4xx_nand_flash_init(void)
+{
+ return platform_driver_register(&ixp4xx_nand_flash_driver);
+}
+
+static void __exit ixp4xx_nand_flash_exit(void)
+{
+ platform_driver_unregister(&ixp4xx_nand_flash_driver);
+}
+
+module_init(ixp4xx_nand_flash_init);
+module_exit(ixp4xx_nand_flash_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("Board-specific glue layer for NAND flash on "
+ "IXP4xx-based platform");
+
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