[MTD] Add support for NDFC NAND controller

NDFC NAND Flash controller is embedded in PPC EP44x SoCs.
Add platform driver based support.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 4d235b91..c2cb87f 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -129,6 +129,12 @@
 	  currently not be able to switch to software, as there is no
 	  implementation for ECC method used by the S3C2410
 
+config MTD_NAND_NDFC
+	tristate "NDFC NanD Flash Controller"
+	depends on MTD_NAND && 44x
+	help
+	 NDFC Nand Flash Controllers are integrated in EP44x SoCs
+
 config MTD_NAND_DISKONCHIP
 	tristate "DiskOnChip 2000, Millennium and Millennium Plus (NAND reimplementation) (EXPERIMENTAL)"
 	depends on MTD_NAND && EXPERIMENTAL
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index 3347508..f747593 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -21,5 +21,6 @@
 obj-$(CONFIG_MTD_NAND_TS7250)		+= ts7250.o
 obj-$(CONFIG_MTD_NAND_NANDSIM)		+= nandsim.o
 obj-$(CONFIG_MTD_NAND_CS553X)		+= cs553x_nand.o
+obj-$(CONFIG_MTD_NAND_NDFC)		+= ndfc.o
 
 nand-objs = nand_base.o nand_bbt.o
diff --git a/drivers/mtd/nand/ndfc.c b/drivers/mtd/nand/ndfc.c
new file mode 100644
index 0000000..22fd682
--- /dev/null
+++ b/drivers/mtd/nand/ndfc.c
@@ -0,0 +1,317 @@
+/*
+ *  drivers/mtd/ndfc.c
+ *
+ *  Overview:
+ *   Platform independend driver for NDFC (NanD Flash Controller)
+ *   integrated into EP440 cores
+ *
+ *  Author: Thomas Gleixner
+ *
+ *  Copyright 2006 IBM
+ *
+ *  This program is free software; you can redistribute	 it and/or modify it
+ *  under  the terms of	 the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the	License, or (at your
+ *  option) any later version.
+ *
+ */
+#include <linux/module.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/nand_ecc.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/ndfc.h>
+#include <linux/mtd/ubi.h>
+#include <linux/mtd/mtd.h>
+#include <linux/platform_device.h>
+
+#include <asm/io.h>
+#include <asm/ibm44x.h>
+
+struct ndfc_nand_mtd {
+	struct mtd_info			mtd;
+	struct nand_chip		chip;
+	struct platform_nand_chip	*pl_chip;
+};
+
+static struct ndfc_nand_mtd ndfc_mtd[NDFC_MAX_BANKS];
+
+struct ndfc_controller {
+	void __iomem		*ndfcbase;
+	struct nand_hw_control	ndfc_control;
+	atomic_t		childs_active;
+};
+
+static struct ndfc_controller ndfc_ctrl;
+
+static void ndfc_select_chip(struct mtd_info *mtd, int chip)
+{
+	uint32_t ccr;
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *nandchip = mtd->priv;
+	struct ndfc_nand_mtd *nandmtd = nandchip->priv;
+	struct platform_nand_chip *pchip = nandmtd->pl_chip;
+
+	ccr = __raw_readl(ndfc->ndfcbase + NDFC_CCR);
+	if (chip >= 0) {
+		ccr &= ~NDFC_CCR_BS_MASK;
+		ccr |= NDFC_CCR_BS(chip + pchip->chip_offset);
+	} else
+		ccr |= NDFC_CCR_RESET_CE;
+	writel(ccr, ndfc->ndfcbase + NDFC_CCR);
+}
+
+static void ndfc_hwcontrol(struct mtd_info *mtd, int cmd)
+{
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *chip = mtd->priv;
+
+	switch (cmd) {
+	case NAND_CTL_SETCLE:
+		chip->IO_ADDR_W = ndfc->ndfcbase + NDFC_CMD;
+		break;
+	case NAND_CTL_SETALE:
+		chip->IO_ADDR_W = ndfc->ndfcbase + NDFC_ALE;
+		break;
+	default:
+		chip->IO_ADDR_W = ndfc->ndfcbase + NDFC_DATA;
+		break;
+	}
+}
+
+static int ndfc_ready(struct mtd_info *mtd)
+{
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+
+	return __raw_readl(ndfc->ndfcbase + NDFC_STAT) & NDFC_STAT_IS_READY;
+}
+
+static void ndfc_enable_hwecc(struct mtd_info *mtd, int mode)
+{
+	uint32_t ccr;
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+
+	ccr = __raw_readl(ndfc->ndfcbase + NDFC_CCR);
+	ccr |= NDFC_CCR_RESET_ECC;
+	__raw_writel(ccr, ndfc->ndfcbase + NDFC_CCR);
+	wmb();
+}
+
+static int ndfc_calculate_ecc(struct mtd_info *mtd,
+			      const u_char *dat, u_char *ecc_code)
+{
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	uint32_t ecc;
+	uint8_t *p = (uint8_t *)&ecc;
+
+	wmb();
+	ecc = __raw_readl(ndfc->ndfcbase + NDFC_ECC);
+	ecc_code[0] = p[1];
+	ecc_code[1] = p[2];
+	ecc_code[2] = p[3];
+
+	return 0;
+}
+
+/*
+ * Speedups for buffer read/write/verify
+ *
+ * NDFC allows 32bit read/write of data. So we can speed up the buffer
+ * functions. No further checking, as nand_base will always read/write
+ * page aligned.
+ */
+static void ndfc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	uint32_t *p = (uint32_t *) buf;
+
+	for(;len > 0; len -= 4)
+		*p++ = __raw_readl(ndfc->ndfcbase + NDFC_DATA);
+}
+
+static void ndfc_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	uint32_t *p = (uint32_t *) buf;
+
+	for(;len > 0; len -= 4)
+		__raw_writel(*p++, ndfc->ndfcbase + NDFC_DATA);
+}
+
+static int ndfc_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	uint32_t *p = (uint32_t *) buf;
+
+	for(;len > 0; len -= 4)
+		if (*p++ != __raw_readl(ndfc->ndfcbase + NDFC_DATA))
+			return -EFAULT;
+	return 0;
+}
+
+/*
+ * Initialize chip structure
+ */
+static void ndfc_chip_init(struct ndfc_nand_mtd *mtd)
+{
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *chip = &mtd->chip;
+
+	chip->IO_ADDR_R = ndfc->ndfcbase + NDFC_DATA;
+	chip->IO_ADDR_W = ndfc->ndfcbase + NDFC_DATA;
+	chip->hwcontrol = ndfc_hwcontrol;
+	chip->dev_ready = ndfc_ready;
+	chip->select_chip = ndfc_select_chip;
+	chip->chip_delay = 50;
+	chip->priv = mtd;
+	chip->options = mtd->pl_chip->options;
+	chip->controller = &ndfc->ndfc_control;
+	chip->read_buf = ndfc_read_buf;
+	chip->write_buf = ndfc_write_buf;
+	chip->verify_buf = ndfc_verify_buf;
+	chip->correct_data  = nand_correct_data;
+	chip->enable_hwecc  = ndfc_enable_hwecc;
+	chip->calculate_ecc = ndfc_calculate_ecc;
+	chip->eccmode = NAND_ECC_HW3_256;
+	chip->autooob = mtd->pl_chip->autooob;
+	mtd->mtd.priv = chip;
+	mtd->mtd.owner = THIS_MODULE;
+}
+
+static int ndfc_chip_probe(struct platform_device *pdev)
+{
+	int rc;
+	struct platform_nand_chip *nc = pdev->dev.platform_data;
+	struct ndfc_chip_settings *settings = nc->priv;
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct ndfc_nand_mtd *nandmtd;
+
+	if (nc->chip_offset >= NDFC_MAX_BANKS || nc->nr_chips > NDFC_MAX_BANKS)
+		return -EINVAL;
+
+	/* Set the bank settings */
+	__raw_writel(settings->bank_settings,
+		     ndfc->ndfcbase + NDFC_BCFG0 + (nc->chip_offset << 2));
+
+	nandmtd = &ndfc_mtd[pdev->id];
+	if (nandmtd->pl_chip)
+		return -EBUSY;
+
+	nandmtd->pl_chip = nc;
+	ndfc_chip_init(nandmtd);
+
+	/* Scan for chips */
+	if (nand_scan(&nandmtd->mtd, nc->nr_chips)) {
+		nandmtd->pl_chip = NULL;
+		return -ENODEV;
+	}
+
+#ifdef CONFIG_MTD_PARTITIONS
+	printk("Number of partitions %d\n", nc->nr_partitions);
+	if (nc->nr_partitions) {
+		struct mtd_info *mtd_ubi;
+		nc->partitions[NAND_PARTS_CONTENT_IDX].mtdp = &mtd_ubi;
+
+		add_mtd_device(&nandmtd->mtd); /* for testing */
+		add_mtd_partitions(&nandmtd->mtd,
+				   nc->partitions,
+				   nc->nr_partitions);
+
+		add_mtd_device(mtd_ubi);
+
+	} else
+#else
+		add_mtd_device(&nandmtd->mtd);
+#endif
+
+	atomic_inc(&ndfc->childs_active);
+	return 0;
+}
+
+static int ndfc_chip_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static int ndfc_nand_probe(struct platform_device *pdev)
+{
+	struct platform_nand_ctrl *nc = pdev->dev.platform_data;
+	struct ndfc_controller_settings *settings = nc->priv;
+	struct resource *res = pdev->resource;
+	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	unsigned long long phys = NDFC_PHYSADDR_OFFS | res->start;
+
+	ndfc->ndfcbase = ioremap64(phys, res->end - res->start + 1);
+	if (!ndfc->ndfcbase) {
+		printk(KERN_ERR "NDFC: ioremap failed\n");
+		return -EIO;
+	}
+
+	__raw_writel(settings->ccr_settings, ndfc->ndfcbase + NDFC_CCR);
+
+	spin_lock_init(&ndfc->ndfc_control.lock);
+	init_waitqueue_head(&ndfc->ndfc_control.wq);
+
+	platform_set_drvdata(pdev, ndfc);
+
+	printk("NDFC NAND Driver initialized. Chip-Rev: 0x%08x\n",
+	       __raw_readl(ndfc->ndfcbase + NDFC_REVID));
+
+	return 0;
+}
+
+static int ndfc_nand_remove(struct platform_device *pdev)
+{
+	struct ndfc_controller *ndfc = platform_get_drvdata(pdev);
+
+	if (atomic_read(&ndfc->childs_active))
+		return -EBUSY;
+
+	if (ndfc) {
+		platform_set_drvdata(pdev, NULL);
+		iounmap(ndfc_ctrl.ndfcbase);
+		ndfc_ctrl.ndfcbase = NULL;
+	}
+	return 0;
+}
+
+/* driver device registration */
+
+static struct platform_driver ndfc_chip_driver = {
+	.probe		= ndfc_chip_probe,
+	.remove		= ndfc_chip_remove,
+	.driver		= {
+		.name	= "ndfc-chip",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static struct platform_driver ndfc_nand_driver = {
+	.probe		= ndfc_nand_probe,
+	.remove		= ndfc_nand_remove,
+	.driver		= {
+		.name	= "ndfc-nand",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init ndfc_nand_init(void)
+{
+	int ret = platform_driver_register(&ndfc_nand_driver);
+
+	if (!ret)
+		ret = platform_driver_register(&ndfc_chip_driver);
+	return ret;
+}
+
+static void __exit ndfc_nand_exit(void)
+{
+	platform_driver_unregister(&ndfc_chip_driver);
+	platform_driver_unregister(&ndfc_nand_driver);
+}
+
+module_init(ndfc_nand_init);
+module_exit(ndfc_nand_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Thomas Gleixner <tglx@linutronix.de>");
+MODULE_DESCRIPTION("Platform driver for NDFC");