[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 186ea9dc094..e5ed081c42c 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 243c7592a11..932301a888e 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 00000000000..cb376b20695
--- /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");