[PATCH] OneNAND: Add simulator

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

3 files changed, 474 insertions, 0 deletions

diff --git a/drivers/mtd/onenand/Kconfig b/drivers/mtd/onenand/Kconfig
index 186ea9d..e5ed081 100644
--- a/drivers/mtd/onenand/Kconfig
+++ b/drivers/mtd/onenand/Kconfig
@@ -35,4 +35,11 @@ config MTD_ONENAND_SYNC_READ
 	help
 	  This enables support for Sync. Burst Read.
 
+config MTD_ONENAND_SIM
+	tristate "Support for OneNAND flash simulator"
+	depends on MTD_ONENAND
+	help
+	  The simulator may simulate verious OneNAND flash chips for the
+          MTD onenand layer.
+
 endmenu
diff --git a/drivers/mtd/onenand/Makefile b/drivers/mtd/onenand/Makefile
index 243c759..932301a 100644
--- a/drivers/mtd/onenand/Makefile
+++ b/drivers/mtd/onenand/Makefile
@@ -8,4 +8,7 @@ obj-$(CONFIG_MTD_ONENAND)		+= onenand.o
 # Board specific.
 obj-$(CONFIG_MTD_ONENAND_OMAP)		+= omap-onenand.o
 
+# Simulator
+obj-$(CONFIG_MTD_ONENAND_SIM)		+= onenand_sim.o
+
 onenand-objs = onenand_base.o onenand_bbt.o
diff --git a/drivers/mtd/onenand/onenand_sim.c b/drivers/mtd/onenand/onenand_sim.c
new file mode 100644
index 0000000..cb376b20
--- /dev/null
+++ b/drivers/mtd/onenand/onenand_sim.c
@@ -0,0 +1,464 @@
+/*
+ *  linux/drivers/mtd/onenand/simulator.c
+ *
+ *  The OneNAND simulator
+ *
+ *  Copyright(c) 2005 Samsung Electronics
+ *  Kyungmin Park <kyungmin.park@samsung.com>
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/vmalloc.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/onenand.h>
+
+#include <asm/io.h>
+#include <asm/sizes.h>
+
+#ifndef CONFIG_ONENAND_SIM_MANUFACTURER
+#define CONFIG_ONENAND_SIM_MANUFACTURER		0xec
+#endif
+#ifndef CONFIG_ONENAND_SIM_DEVICE_ID
+#define CONFIG_ONENAND_SIM_DEVICE_ID		0x04
+#endif
+#ifndef CONFIG_ONENAND_SIM_VERSION_ID
+#define CONFIG_ONENAND_SIM_VERSION_ID		0x1e
+#endif
+
+static int manuf_id = CONFIG_ONENAND_SIM_MANUFACTURER;
+static int device_id = CONFIG_ONENAND_SIM_DEVICE_ID;
+static int version_id = CONFIG_ONENAND_SIM_VERSION_ID;
+
+struct onenand_flash {
+	void __iomem	*base;
+	void __iomem	*data;
+};
+
+#define ONENAND_CORE(flash)	(flash->data)
+
+#define ONENAND_MAIN_AREA(this, offset)					\
+	(this->base + ONENAND_DATARAM + offset)
+
+#define ONENAND_SPARE_AREA(this, offset)				\
+	(this->base + ONENAND_SPARERAM + offset)
+
+#define ONENAND_GET_WP_STATUS(this)					\
+	(readw(this->base + ONENAND_REG_WP_STATUS))
+
+#define ONENAND_SET_WP_STATUS(v, this)					\
+	(writew(v, this->base + ONENAND_REG_WP_STATUS))
+
+/* It has all 0xff chars */
+static unsigned char *ffchars;
+
+/*
+ * OneNAND simulator mtd
+ */
+struct mtd_info *onenand_sim;
+
+
+/**
+ * onenand_lock_handle - Handle Lock scheme
+ * @param this		OneNAND device structure
+ * @param cmd		The command to be sent
+ *
+ * Send lock command to OneNAND device.
+ * The lock scheme is depends on chip type.
+ */
+static void onenand_lock_handle(struct onenand_chip *this, int cmd)
+{
+	int block_lock_scheme;
+	int status;
+
+	status = ONENAND_GET_WP_STATUS(this);
+	block_lock_scheme = !(this->options & ONENAND_CONT_LOCK);
+	
+	switch (cmd) {
+	case ONENAND_CMD_UNLOCK:
+		if (block_lock_scheme)
+			ONENAND_SET_WP_STATUS(ONENAND_WP_US, this);
+		else
+			ONENAND_SET_WP_STATUS(status | ONENAND_WP_US, this);
+		break;
+
+	case ONENAND_CMD_LOCK:
+		if (block_lock_scheme)
+			ONENAND_SET_WP_STATUS(ONENAND_WP_LS, this);
+		else
+			ONENAND_SET_WP_STATUS(status | ONENAND_WP_LS, this);
+		break;
+
+	case ONENAND_CMD_LOCK_TIGHT:
+		if (block_lock_scheme)
+			ONENAND_SET_WP_STATUS(ONENAND_WP_LTS, this);
+		else
+			ONENAND_SET_WP_STATUS(status | ONENAND_WP_LTS, this);
+		break;
+
+	default:
+		break;
+	}
+}
+
+/**
+ * onenand_bootram_handle - Handle BootRAM area
+ * @param this		OneNAND device structure
+ * @param cmd		The command to be sent
+ *
+ * Emulate BootRAM area. It is possible to do basic operation using BootRAM.
+ */
+static void onenand_bootram_handle(struct onenand_chip *this, int cmd)
+{
+	switch (cmd) {
+	case ONENAND_CMD_READID:
+		writew(manuf_id, this->base);
+		writew(device_id, this->base + 2);
+		writew(version_id, this->base + 4);
+		break;
+
+	default:
+		/* REVIST: Handle other commands */
+		break;
+	}
+}
+
+/**
+ * onenand_update_interrupt - Set interrupt register
+ * @param this		OneNAND device structure
+ * @param cmd		The command to be sent
+ *
+ * Update interrupt register. The status is depends on command.
+ */
+static void onenand_update_interrupt(struct onenand_chip *this, int cmd)
+{
+	int interrupt = ONENAND_INT_MASTER;
+
+	switch (cmd) {
+	case ONENAND_CMD_READ:
+	case ONENAND_CMD_READOOB:
+		interrupt |= ONENAND_INT_READ;
+		break;
+
+	case ONENAND_CMD_PROG:
+	case ONENAND_CMD_PROGOOB:
+		interrupt |= ONENAND_INT_WRITE;
+		break;
+
+	case ONENAND_CMD_ERASE:
+		interrupt |= ONENAND_INT_ERASE;
+		break;
+
+	case ONENAND_CMD_RESET:
+		interrupt |= ONENAND_INT_RESET;
+		break;
+
+	default:
+		break;
+	}
+
+	writew(interrupt, this->base + ONENAND_REG_INTERRUPT);
+}
+
+/**
+ * onenand_check_overwrite - Check over-write if happend
+ * @param dest		The destination pointer
+ * @param src		The source pointer
+ * @param count		The length to be check
+ * @return 		0 on same, otherwise 1
+ *
+ * Compare the source with destination
+ */
+static int onenand_check_overwrite(void *dest, void *src, size_t count)
+{
+	unsigned int *s = (unsigned int *) src;
+	unsigned int *d = (unsigned int *) dest;
+	int i;
+	count >>= 2;
+
+	for (i = 0; i < count; i++)
+		if ((*s++ ^ *d++) != 0)
+			return 1;
+
+	return 0;
+}
+
+/**
+ * onenand_data_handle - Handle OneNAND Core and DataRAM
+ * @param this		OneNAND device structure
+ * @param cmd		The command to be sent
+ * @param dataram	Which dataram used
+ * @param offset	The offset to OneNAND Core
+ *
+ * Copy data from OneNAND Core to DataRAM (read)
+ * Copy data from DataRAM to OneNAND Core (write)
+ * Erase the OneNAND Core (erase)
+ */
+static void onenand_data_handle(struct onenand_chip *this, int cmd,
+					int dataram, unsigned int offset)
+{
+	struct onenand_flash *flash = this->priv;
+	int main_offset, spare_offset;
+	void __iomem *src;
+	void __iomem *dest;
+
+	if (dataram) {
+		main_offset = onenand_sim->oobblock;
+		spare_offset = onenand_sim->oobsize;
+	} else {
+		main_offset = 0;
+		spare_offset = 0;
+	}
+
+	switch (cmd) {
+	case ONENAND_CMD_READ:
+		src = ONENAND_CORE(flash) + offset;
+		dest = ONENAND_MAIN_AREA(this, main_offset);
+		memcpy(dest, src, onenand_sim->oobblock);
+		/* Fall through */
+
+	case ONENAND_CMD_READOOB:
+		src = ONENAND_CORE(flash) + this->chipsize + (offset >> 5);
+		dest = ONENAND_SPARE_AREA(this, spare_offset);
+		memcpy(dest, src, onenand_sim->oobsize);
+		break;
+
+	case ONENAND_CMD_PROG:
+		src = ONENAND_MAIN_AREA(this, main_offset);
+		dest = ONENAND_CORE(flash) + offset;
+		if (memcmp(dest, ffchars, onenand_sim->oobblock) &&
+		    onenand_check_overwrite(dest, src, onenand_sim->oobblock))
+			printk(KERN_ERR "over-write happend at 0x%08x\n", offset);
+		memcpy(dest, src, onenand_sim->oobblock);
+		/* Fall through */
+
+	case ONENAND_CMD_PROGOOB:
+		src = ONENAND_SPARE_AREA(this, spare_offset);
+		/* Check all data is 0xff chars */
+		if (!memcmp(src, ffchars, onenand_sim->oobsize))
+			break;
+
+		dest = ONENAND_CORE(flash) + this->chipsize + (offset >> 5);
+		if (memcmp(dest, ffchars, onenand_sim->oobsize) &&
+		    onenand_check_overwrite(dest, src, onenand_sim->oobsize)) 
+			printk(KERN_ERR "OOB: over-write happend at 0x%08x\n", offset);
+		memcpy(dest, src, onenand_sim->oobsize);
+		break;
+
+	case ONENAND_CMD_ERASE:
+		memset(ONENAND_CORE(flash) + offset, 0xff, (1 << this->erase_shift));
+		break;
+
+	default:
+		break;
+	}
+}
+
+/**
+ * onenand_command_handle - Handle command
+ * @param this		OneNAND device structure
+ * @param cmd		The command to be sent
+ *
+ * Emulate OneNAND command.
+ */
+static void onenand_command_handle(struct onenand_chip *this, int cmd)
+{
+	unsigned long offset = 0;
+	int block = -1, page = -1, bufferram = -1;
+	int dataram = 0;
+
+	switch (cmd) {
+	case ONENAND_CMD_UNLOCK:
+	case ONENAND_CMD_LOCK:
+	case ONENAND_CMD_LOCK_TIGHT:
+		onenand_lock_handle(this, cmd);
+		break;
+
+	case ONENAND_CMD_BUFFERRAM:
+		/* Do nothing */
+		return;
+
+	default:
+		block = (int) readw(this->base + ONENAND_REG_START_ADDRESS1);
+		if (block & (1 << ONENAND_DDP_SHIFT)) {
+			block &= ~(1 << ONENAND_DDP_SHIFT);
+			/* The half of chip block */
+			block += this->chipsize >> (this->erase_shift + 1);
+		}
+		if (cmd == ONENAND_CMD_ERASE)
+			break;
+
+		page = (int) readw(this->base + ONENAND_REG_START_ADDRESS8);
+		page = (page >> ONENAND_FPA_SHIFT);
+		bufferram = (int) readw(this->base + ONENAND_REG_START_BUFFER);
+		bufferram >>= ONENAND_BSA_SHIFT;
+		bufferram &= ONENAND_BSA_DATARAM1;
+		dataram = (bufferram == ONENAND_BSA_DATARAM1) ? 1 : 0;
+		break;
+	}
+
+	if (block != -1)
+		offset += block << this->erase_shift;
+
+	if (page != -1)
+		offset += page << this->page_shift;
+
+	onenand_data_handle(this, cmd, dataram, offset);
+
+	onenand_update_interrupt(this, cmd);
+}
+
+/**
+ * onenand_writew - [OneNAND Interface] Emulate write operation
+ * @param value		value to write
+ * @param addr		address to write
+ *
+ * Write OneNAND reigser with value
+ */
+static void onenand_writew(unsigned short value, void __iomem *addr)
+{
+	struct onenand_chip *this = onenand_sim->priv;
+
+	/* BootRAM handling */
+	if (addr < this->base + ONENAND_DATARAM) {
+		onenand_bootram_handle(this, value);
+		return;
+	}
+	/* Command handling */
+	if (addr == this->base + ONENAND_REG_COMMAND)
+		onenand_command_handle(this, value);
+
+	writew(value, addr);
+}
+
+/**
+ * flash_init - Initialize OneNAND simulator
+ * @param flash		OneNAND simulaotr data strucutres
+ *
+ * Initialize OneNAND simulator.
+ */
+static int __init flash_init(struct onenand_flash *flash)
+{
+	int density, size;
+	int buffer_size;
+
+	flash->base = kmalloc(SZ_128K, GFP_KERNEL);
+	if (!flash->base) {
+		printk(KERN_ERR "Unalbe to allocate base address.\n");
+		return -ENOMEM;
+	}
+
+	memset(flash->base, 0, SZ_128K);
+
+	density = device_id >> ONENAND_DEVICE_DENSITY_SHIFT;
+	size = ((16 << 20) << density);
+
+	ONENAND_CORE(flash) = vmalloc(size + (size >> 5));
+	if (!ONENAND_CORE(flash)) {
+		printk(KERN_ERR "Unalbe to allocate nand core address.\n");
+		kfree(flash->base);
+		return -ENOMEM;
+	}
+
+	memset(ONENAND_CORE(flash), 0xff, size + (size >> 5));
+
+	/* Setup registers */
+	writew(manuf_id, flash->base + ONENAND_REG_MANUFACTURER_ID);
+	writew(device_id, flash->base + ONENAND_REG_DEVICE_ID);
+	writew(version_id, flash->base + ONENAND_REG_VERSION_ID);
+
+	if (density < 2)
+		buffer_size = 0x0400;	/* 1KB page */
+	else
+		buffer_size = 0x0800;	/* 2KB page */
+	writew(buffer_size, flash->base + ONENAND_REG_DATA_BUFFER_SIZE);
+		
+	return 0;
+}
+
+/**
+ * flash_exit - Clean up OneNAND simulator
+ * @param flash		OneNAND simulaotr data strucutres
+ *
+ * Clean up OneNAND simulator.
+ */
+static void flash_exit(struct onenand_flash *flash)
+{
+	vfree(ONENAND_CORE(flash));
+	kfree(flash->base);
+	kfree(flash);
+}
+
+static int __init onenand_sim_init(void)
+{
+	struct onenand_chip *this;
+	struct onenand_flash *flash;
+	int len;
+
+	/* Allocate all 0xff chars pointer */
+	ffchars = kmalloc(MAX_ONENAND_PAGESIZE, GFP_KERNEL);
+	if (!ffchars) {
+		printk(KERN_ERR "Unable to allocate ff chars.\n");
+		return -ENOMEM;
+	}
+	memset(ffchars, 0xff, MAX_ONENAND_PAGESIZE);
+
+	len = sizeof(struct mtd_info) + sizeof(struct onenand_chip) + sizeof (struct onenand_flash);
+
+	/* Allocate OneNAND simulator mtd pointer */
+	onenand_sim = kmalloc(len, GFP_KERNEL);
+	if (!onenand_sim) {
+		printk(KERN_ERR "Unable to allocate core structures.\n");
+		kfree(ffchars);
+		return -ENOMEM;
+	}
+
+	memset(onenand_sim, 0, len);
+
+	this = (struct onenand_chip *) (onenand_sim + 1);
+	/* Override write_word function */
+	this->write_word = onenand_writew;
+
+	flash = (struct onenand_flash *) (this + 1);
+
+	if (flash_init(flash)) {
+		printk(KERN_ERR "Unable to allocat flash.\n");
+		kfree(ffchars);
+		kfree(onenand_sim);
+		return -ENOMEM;
+	}
+
+	this->base = flash->base;
+	this->priv = flash;
+	onenand_sim->priv = this;
+
+	if (onenand_scan(onenand_sim, 1)) {
+		kfree(ffchars);
+		kfree(onenand_sim);
+		flash_exit(flash);
+		return -ENXIO;
+	}
+
+	add_mtd_device(onenand_sim);
+
+	return 0;
+}
+
+static void __exit onenand_sim_exit(void)
+{
+	struct onenand_chip *this = onenand_sim->priv;
+	struct onenand_flash *flash = this->priv;
+
+	kfree(ffchars);
+	onenand_release(onenand_sim);
+	flash_exit(flash);
+	kfree(onenand_sim);
+}
+
+module_init(onenand_sim_init);
+module_exit(onenand_sim_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Kyungmin Park <kyungmin.park@samsung.com>");
+MODULE_DESCRIPTION("The OneNAND flash simulator");