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authorunsik Kim <donari75@gmail.com>2009-04-02 12:50:58 -0700
committerJens Axboe <jens.axboe@oracle.com>2009-04-07 08:12:38 +0200
commit3fbed4c61abd8458896e38633d10110cb5a589d4 (patch)
tree6024567b36cc26c4d6fddef59fab222651310dec /include/linux/mg_disk.h
parente143858104e318263689c551543dfc3f186cea12 (diff)
mflash: initial support
This driver supports mflash IO mode for linux. Mflash is embedded flash drive and mainly targeted mobile and consumer electronic devices. Internally, mflash has nand flash and other hardware logics and supports 2 different operation (ATA, IO) modes. ATA mode doesn't need any new driver and currently works well under standard IDE subsystem. Actually it's one chip SSD. IO mode is ATA-like custom mode for the host that doesn't have IDE interface. Followings are brief descriptions about IO mode. A. IO mode based on ATA protocol and uses some custom command. (read confirm, write confirm) B. IO mode uses SRAM bus interface. C. IO mode supports 4kB boot area, so host can boot from mflash. This driver is quitely similar to a standard ATA driver, but because of following reasons it is currently seperated with ATA layer. 1. ATA layer deals standard ATA protocol. ATA layer have many low- level device specific interface, but data transfer keeps ATA rule. But, mflash IO mode doesn't. 2. Even though currently not used in mflash driver code, mflash has some custom command and modes. (nand fusing, firmware patch, etc) If this feature supported in linux kernel, ATA layer more altered. 3. Currently PATA platform device driver doesn't support interrupt. (I'm not sure) But, mflash uses interrupt (polling mode is just for debug). 4. mflash is somewhat under-develop product. Even though some company already using mflash their own product, I think more time is needed for standardization of custom command and mode. That time (maybe October) I will talk to with ATA people. If they accept integration, I will integrate. Signed-off-by: unsik Kim <donari75@gmail.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'include/linux/mg_disk.h')
-rw-r--r--include/linux/mg_disk.h206
1 files changed, 206 insertions, 0 deletions
diff --git a/include/linux/mg_disk.h b/include/linux/mg_disk.h
new file mode 100644
index 000000000000..1f76b1ebf627
--- /dev/null
+++ b/include/linux/mg_disk.h
@@ -0,0 +1,206 @@
+/*
+ * include/linux/mg_disk.c
+ *
+ * Support for the mGine m[g]flash IO mode.
+ * Based on legacy hd.c
+ *
+ * (c) 2008 mGine Co.,LTD
+ * (c) 2008 unsik Kim <donari75@gmail.com>
+ *
+ * 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.
+ */
+
+#ifndef __MG_DISK_H__
+#define __MG_DISK_H__
+
+#include <linux/blkdev.h>
+#include <linux/ata.h>
+
+/* name for block device */
+#define MG_DISK_NAME "mgd"
+/* name for platform device */
+#define MG_DEV_NAME "mg_disk"
+
+#define MG_DISK_MAJ 0
+#define MG_DISK_MAX_PART 16
+#define MG_SECTOR_SIZE 512
+#define MG_MAX_SECTS 256
+
+/* Register offsets */
+#define MG_BUFF_OFFSET 0x8000
+#define MG_STORAGE_BUFFER_SIZE 0x200
+#define MG_REG_OFFSET 0xC000
+#define MG_REG_FEATURE (MG_REG_OFFSET + 2) /* write case */
+#define MG_REG_ERROR (MG_REG_OFFSET + 2) /* read case */
+#define MG_REG_SECT_CNT (MG_REG_OFFSET + 4)
+#define MG_REG_SECT_NUM (MG_REG_OFFSET + 6)
+#define MG_REG_CYL_LOW (MG_REG_OFFSET + 8)
+#define MG_REG_CYL_HIGH (MG_REG_OFFSET + 0xA)
+#define MG_REG_DRV_HEAD (MG_REG_OFFSET + 0xC)
+#define MG_REG_COMMAND (MG_REG_OFFSET + 0xE) /* write case */
+#define MG_REG_STATUS (MG_REG_OFFSET + 0xE) /* read case */
+#define MG_REG_DRV_CTRL (MG_REG_OFFSET + 0x10)
+#define MG_REG_BURST_CTRL (MG_REG_OFFSET + 0x12)
+
+/* "Drive Select/Head Register" bit values */
+#define MG_REG_HEAD_MUST_BE_ON 0xA0 /* These 2 bits are always on */
+#define MG_REG_HEAD_DRIVE_MASTER (0x00 | MG_REG_HEAD_MUST_BE_ON)
+#define MG_REG_HEAD_DRIVE_SLAVE (0x10 | MG_REG_HEAD_MUST_BE_ON)
+#define MG_REG_HEAD_LBA_MODE (0x40 | MG_REG_HEAD_MUST_BE_ON)
+
+
+/* "Device Control Register" bit values */
+#define MG_REG_CTRL_INTR_ENABLE 0x0
+#define MG_REG_CTRL_INTR_DISABLE (0x1<<1)
+#define MG_REG_CTRL_RESET (0x1<<2)
+#define MG_REG_CTRL_INTR_POLA_ACTIVE_HIGH 0x0
+#define MG_REG_CTRL_INTR_POLA_ACTIVE_LOW (0x1<<4)
+#define MG_REG_CTRL_DPD_POLA_ACTIVE_LOW 0x0
+#define MG_REG_CTRL_DPD_POLA_ACTIVE_HIGH (0x1<<5)
+#define MG_REG_CTRL_DPD_DISABLE 0x0
+#define MG_REG_CTRL_DPD_ENABLE (0x1<<6)
+
+/* Status register bit */
+/* error bit in status register */
+#define MG_REG_STATUS_BIT_ERROR 0x01
+/* corrected error in status register */
+#define MG_REG_STATUS_BIT_CORRECTED_ERROR 0x04
+/* data request bit in status register */
+#define MG_REG_STATUS_BIT_DATA_REQ 0x08
+/* DSC - Drive Seek Complete */
+#define MG_REG_STATUS_BIT_SEEK_DONE 0x10
+/* DWF - Drive Write Fault */
+#define MG_REG_STATUS_BIT_WRITE_FAULT 0x20
+#define MG_REG_STATUS_BIT_READY 0x40
+#define MG_REG_STATUS_BIT_BUSY 0x80
+
+/* handy status */
+#define MG_STAT_READY (MG_REG_STATUS_BIT_READY | MG_REG_STATUS_BIT_SEEK_DONE)
+#define MG_READY_OK(s) (((s) & (MG_STAT_READY | \
+ (MG_REG_STATUS_BIT_BUSY | \
+ MG_REG_STATUS_BIT_WRITE_FAULT | \
+ MG_REG_STATUS_BIT_ERROR))) == MG_STAT_READY)
+
+/* Error register */
+#define MG_REG_ERR_AMNF 0x01
+#define MG_REG_ERR_ABRT 0x04
+#define MG_REG_ERR_IDNF 0x10
+#define MG_REG_ERR_UNC 0x40
+#define MG_REG_ERR_BBK 0x80
+
+/* error code for others */
+#define MG_ERR_NONE 0
+#define MG_ERR_TIMEOUT 0x100
+#define MG_ERR_INIT_STAT 0x101
+#define MG_ERR_TRANSLATION 0x102
+#define MG_ERR_CTRL_RST 0x103
+#define MG_ERR_INV_STAT 0x104
+#define MG_ERR_RSTOUT 0x105
+
+#define MG_MAX_ERRORS 6 /* Max read/write errors */
+
+/* command */
+#define MG_CMD_RD 0x20
+#define MG_CMD_WR 0x30
+#define MG_CMD_SLEEP 0x99
+#define MG_CMD_WAKEUP 0xC3
+#define MG_CMD_ID 0xEC
+#define MG_CMD_WR_CONF 0x3C
+#define MG_CMD_RD_CONF 0x40
+
+/* operation mode */
+#define MG_OP_CASCADE (1 << 0)
+#define MG_OP_CASCADE_SYNC_RD (1 << 1)
+#define MG_OP_CASCADE_SYNC_WR (1 << 2)
+#define MG_OP_INTERLEAVE (1 << 3)
+
+/* synchronous */
+#define MG_BURST_LAT_4 (3 << 4)
+#define MG_BURST_LAT_5 (4 << 4)
+#define MG_BURST_LAT_6 (5 << 4)
+#define MG_BURST_LAT_7 (6 << 4)
+#define MG_BURST_LAT_8 (7 << 4)
+#define MG_BURST_LEN_4 (1 << 1)
+#define MG_BURST_LEN_8 (2 << 1)
+#define MG_BURST_LEN_16 (3 << 1)
+#define MG_BURST_LEN_32 (4 << 1)
+#define MG_BURST_LEN_CONT (0 << 1)
+
+/* timeout value (unit: ms) */
+#define MG_TMAX_CONF_TO_CMD 1
+#define MG_TMAX_WAIT_RD_DRQ 10
+#define MG_TMAX_WAIT_WR_DRQ 500
+#define MG_TMAX_RST_TO_BUSY 10
+#define MG_TMAX_HDRST_TO_RDY 500
+#define MG_TMAX_SWRST_TO_RDY 500
+#define MG_TMAX_RSTOUT 3000
+
+/* device attribution */
+/* use mflash as boot device */
+#define MG_BOOT_DEV (1 << 0)
+/* use mflash as storage device */
+#define MG_STORAGE_DEV (1 << 1)
+/* same as MG_STORAGE_DEV, but bootloader already done reset sequence */
+#define MG_STORAGE_DEV_SKIP_RST (1 << 2)
+
+#define MG_DEV_MASK (MG_BOOT_DEV | MG_STORAGE_DEV | MG_STORAGE_DEV_SKIP_RST)
+
+/* names of GPIO resource */
+#define MG_RST_PIN "mg_rst"
+/* except MG_BOOT_DEV, reset-out pin should be assigned */
+#define MG_RSTOUT_PIN "mg_rstout"
+
+/* private driver data */
+struct mg_drv_data {
+ /* disk resource */
+ u32 use_polling;
+
+ /* device attribution */
+ u32 dev_attr;
+
+ /* internally used */
+ struct mg_host *host;
+};
+
+/* main structure for mflash driver */
+struct mg_host {
+ struct device *dev;
+
+ struct request_queue *breq;
+ spinlock_t lock;
+ struct gendisk *gd;
+
+ struct timer_list timer;
+ void (*mg_do_intr) (struct mg_host *);
+
+ u16 id[ATA_ID_WORDS];
+
+ u16 cyls;
+ u16 heads;
+ u16 sectors;
+ u32 n_sectors;
+ u32 nres_sectors;
+
+ void __iomem *dev_base;
+ unsigned int irq;
+ unsigned int rst;
+ unsigned int rstout;
+
+ u32 major;
+ u32 error;
+};
+
+/*
+ * Debugging macro and defines
+ */
+#undef DO_MG_DEBUG
+#ifdef DO_MG_DEBUG
+# define MG_DBG(fmt, args...) \
+ printk(KERN_DEBUG "%s:%d "fmt, __func__, __LINE__, ##args)
+#else /* CONFIG_MG_DEBUG */
+# define MG_DBG(fmt, args...) do { } while (0)
+#endif /* CONFIG_MG_DEBUG */
+
+#endif