| /* |
| * 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 <mach/hardware.h> |
| #include <asm/sizes.h> |
| #include <mach/gpio.h> |
| #include <mach/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) ? AMS_DELTA_LATCH2_NAND_NCE : 0; |
| bits |= (ctrl & NAND_CLE) ? AMS_DELTA_LATCH2_NAND_CLE : 0; |
| bits |= (ctrl & NAND_ALE) ? AMS_DELTA_LATCH2_NAND_ALE : 0; |
| |
| ams_delta_latch2_write(AMS_DELTA_LATCH2_NAND_CLE | |
| AMS_DELTA_LATCH2_NAND_ALE | |
| AMS_DELTA_LATCH2_NAND_NCE, bits); |
| } |
| |
| if (cmd != NAND_CMD_NONE) |
| ams_delta_write_byte(mtd, cmd); |
| } |
| |
| static int ams_delta_nand_ready(struct mtd_info *mtd) |
| { |
| return gpio_get_value(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 (gpio_request(AMS_DELTA_GPIO_PIN_NAND_RB, "nand_rdy") == 0) { |
| 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)"); |