linux/include/mtd/mtd-abi.h

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/*
* Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifndef __MTD_ABI_H__
#define __MTD_ABI_H__
#include <linux/types.h>
struct erase_info_user {
__u32 start;
__u32 length;
};
struct erase_info_user64 {
__u64 start;
__u64 length;
};
struct mtd_oob_buf {
__u32 start;
__u32 length;
unsigned char __user *ptr;
};
struct mtd_oob_buf64 {
__u64 start;
__u32 pad;
__u32 length;
__u64 usr_ptr;
};
/**
* MTD operation modes
*
* @MTD_OPS_PLACE_OOB: OOB data are placed at the given offset (default)
* @MTD_OPS_AUTO_OOB: OOB data are automatically placed at the free areas
* which are defined by the internal ecclayout
* @MTD_OPS_RAW: data are transferred as-is, with no error correction;
* this mode implies %MTD_OPS_PLACE_OOB
*
* These modes can be passed to ioctl(MEMWRITE) and are also used internally.
* See notes on "MTD file modes" for discussion on %MTD_OPS_RAW vs.
* %MTD_FILE_MODE_RAW.
*/
enum {
MTD_OPS_PLACE_OOB = 0,
MTD_OPS_AUTO_OOB = 1,
MTD_OPS_RAW = 2,
};
/**
* struct mtd_write_req - data structure for requesting a write operation
*
* @start: start address
* @len: length of data buffer
* @ooblen: length of OOB buffer
* @usr_data: user-provided data buffer
* @usr_oob: user-provided OOB buffer
* @mode: MTD mode (see "MTD operation modes")
* @padding: reserved, must be set to 0
*
* This structure supports ioctl(MEMWRITE) operations, allowing data and/or OOB
* writes in various modes. To write to OOB-only, set @usr_data == NULL, and to
* write data-only, set @usr_oob == NULL. However, setting both @usr_data and
* @usr_oob to NULL is not allowed.
*/
struct mtd_write_req {
__u64 start;
__u64 len;
__u64 ooblen;
__u64 usr_data;
__u64 usr_oob;
__u8 mode;
__u8 padding[7];
};
#define MTD_ABSENT 0
#define MTD_RAM 1
#define MTD_ROM 2
#define MTD_NORFLASH 3
#define MTD_NANDFLASH 4
#define MTD_DATAFLASH 6
UBI: Unsorted Block Images UBI (Latin: "where?") manages multiple logical volumes on a single flash device, specifically supporting NAND flash devices. UBI provides a flexible partitioning concept which still allows for wear-levelling across the whole flash device. In a sense, UBI may be compared to the Logical Volume Manager (LVM). Whereas LVM maps logical sector numbers to physical HDD sector numbers, UBI maps logical eraseblocks to physical eraseblocks. More information may be found at http://www.linux-mtd.infradead.org/doc/ubi.html Partitioning/Re-partitioning An UBI volume occupies a certain number of erase blocks. This is limited by a configured maximum volume size, which could also be viewed as the partition size. Each individual UBI volume's size can be changed independently of the other UBI volumes, provided that the sum of all volume sizes doesn't exceed a certain limit. UBI supports dynamic volumes and static volumes. Static volumes are read-only and their contents are protected by CRC check sums. Bad eraseblocks handling UBI transparently handles bad eraseblocks. When a physical eraseblock becomes bad, it is substituted by a good physical eraseblock, and the user does not even notice this. Scrubbing On a NAND flash bit flips can occur on any write operation, sometimes also on read. If bit flips persist on the device, at first they can still be corrected by ECC, but once they accumulate, correction will become impossible. Thus it is best to actively scrub the affected eraseblock, by first copying it to a free eraseblock and then erasing the original. The UBI layer performs this type of scrubbing under the covers, transparently to the UBI volume users. Erase Counts UBI maintains an erase count header per eraseblock. This frees higher-level layers (like file systems) from doing this and allows for centralized erase count management instead. The erase counts are used by the wear-levelling algorithm in the UBI layer. The algorithm itself is exchangeable. Booting from NAND For booting directly from NAND flash the hardware must at least be capable of fetching and executing a small portion of the NAND flash. Some NAND flash controllers have this kind of support. They usually limit the window to a few kilobytes in erase block 0. This "initial program loader" (IPL) must then contain sufficient logic to load and execute the next boot phase. Due to bad eraseblocks, which may be randomly scattered over the flash device, it is problematic to store the "secondary program loader" (SPL) statically. Also, due to bit-flips it may become corrupted over time. UBI allows to solve this problem gracefully by storing the SPL in a small static UBI volume. UBI volumes vs. static partitions UBI volumes are still very similar to static MTD partitions: * both consist of eraseblocks (logical eraseblocks in case of UBI volumes, and physical eraseblocks in case of static partitions; * both support three basic operations - read, write, erase. But UBI volumes have the following advantages over traditional static MTD partitions: * there are no eraseblock wear-leveling constraints in case of UBI volumes, so the user should not care about this; * there are no bit-flips and bad eraseblocks in case of UBI volumes. So, UBI volumes may be considered as flash devices with relaxed restrictions. Where can it be found? Documentation, kernel code and applications can be found in the MTD gits. What are the applications for? The applications help to create binary flash images for two purposes: pfi files (partial flash images) for in-system update of UBI volumes, and plain binary images, with or without OOB data in case of NAND, for a manufacturing step. Furthermore some tools are/and will be created that allow flash content analysis after a system has crashed.. Who did UBI? The original ideas, where UBI is based on, were developed by Andreas Arnez, Frank Haverkamp and Thomas Gleixner. Josh W. Boyer and some others were involved too. The implementation of the kernel layer was done by Artem B. Bityutskiy. The user-space applications and tools were written by Oliver Lohmann with contributions from Frank Haverkamp, Andreas Arnez, and Artem. Joern Engel contributed a patch which modifies JFFS2 so that it can be run on a UBI volume. Thomas Gleixner did modifications to the NAND layer. Alexander Schmidt made some testing work as well as core functionality improvements. Signed-off-by: Artem B. Bityutskiy <dedekind@linutronix.de> Signed-off-by: Frank Haverkamp <haver@vnet.ibm.com>
2006-06-27 08:22:22 +00:00
#define MTD_UBIVOLUME 7
#define MTD_MLCNANDFLASH 8
#define MTD_WRITEABLE 0x400 /* Device is writeable */
#define MTD_BIT_WRITEABLE 0x800 /* Single bits can be flipped */
#define MTD_NO_ERASE 0x1000 /* No erase necessary */
#define MTD_POWERUP_LOCK 0x2000 /* Always locked after reset */
/* Some common devices / combinations of capabilities */
#define MTD_CAP_ROM 0
#define MTD_CAP_RAM (MTD_WRITEABLE | MTD_BIT_WRITEABLE | MTD_NO_ERASE)
#define MTD_CAP_NORFLASH (MTD_WRITEABLE | MTD_BIT_WRITEABLE)
#define MTD_CAP_NANDFLASH (MTD_WRITEABLE)
/* Obsolete ECC byte placement modes (used with obsolete MEMGETOOBSEL) */
#define MTD_NANDECC_OFF 0 // Switch off ECC (Not recommended)
#define MTD_NANDECC_PLACE 1 // Use the given placement in the structure (YAFFS1 legacy mode)
#define MTD_NANDECC_AUTOPLACE 2 // Use the default placement scheme
#define MTD_NANDECC_PLACEONLY 3 // Use the given placement in the structure (Do not store ecc result on read)
#define MTD_NANDECC_AUTOPL_USR 4 // Use the given autoplacement scheme rather than using the default
/* OTP mode selection */
#define MTD_OTP_OFF 0
#define MTD_OTP_FACTORY 1
#define MTD_OTP_USER 2
struct mtd_info_user {
__u8 type;
__u32 flags;
__u32 size; /* Total size of the MTD */
__u32 erasesize;
__u32 writesize;
__u32 oobsize; /* Amount of OOB data per block (e.g. 16) */
__u64 padding; /* Old obsolete field; do not use */
};
struct region_info_user {
__u32 offset; /* At which this region starts,
* from the beginning of the MTD */
__u32 erasesize; /* For this region */
__u32 numblocks; /* Number of blocks in this region */
__u32 regionindex;
};
struct otp_info {
__u32 start;
__u32 length;
__u32 locked;
};
/*
* Note, the following ioctl existed in the past and was removed:
* #define MEMSETOOBSEL _IOW('M', 9, struct nand_oobinfo)
* Try to avoid adding a new ioctl with the same ioctl number.
*/
/* Get basic MTD characteristics info (better to use sysfs) */
#define MEMGETINFO _IOR('M', 1, struct mtd_info_user)
/* Erase segment of MTD */
#define MEMERASE _IOW('M', 2, struct erase_info_user)
/* Write out-of-band data from MTD */
#define MEMWRITEOOB _IOWR('M', 3, struct mtd_oob_buf)
/* Read out-of-band data from MTD */
#define MEMREADOOB _IOWR('M', 4, struct mtd_oob_buf)
/* Lock a chip (for MTD that supports it) */
#define MEMLOCK _IOW('M', 5, struct erase_info_user)
/* Unlock a chip (for MTD that supports it) */
#define MEMUNLOCK _IOW('M', 6, struct erase_info_user)
/* Get the number of different erase regions */
#define MEMGETREGIONCOUNT _IOR('M', 7, int)
/* Get information about the erase region for a specific index */
#define MEMGETREGIONINFO _IOWR('M', 8, struct region_info_user)
/* Get info about OOB modes (e.g., RAW, PLACE, AUTO) - legacy interface */
#define MEMGETOOBSEL _IOR('M', 10, struct nand_oobinfo)
/* Check if an eraseblock is bad */
#define MEMGETBADBLOCK _IOW('M', 11, __kernel_loff_t)
/* Mark an eraseblock as bad */
#define MEMSETBADBLOCK _IOW('M', 12, __kernel_loff_t)
/* Set OTP (One-Time Programmable) mode (factory vs. user) */
#define OTPSELECT _IOR('M', 13, int)
/* Get number of OTP (One-Time Programmable) regions */
#define OTPGETREGIONCOUNT _IOW('M', 14, int)
/* Get all OTP (One-Time Programmable) info about MTD */
#define OTPGETREGIONINFO _IOW('M', 15, struct otp_info)
/* Lock a given range of user data (must be in mode %MTD_FILE_MODE_OTP_USER) */
#define OTPLOCK _IOR('M', 16, struct otp_info)
/* Get ECC layout (deprecated) */
#define ECCGETLAYOUT _IOR('M', 17, struct nand_ecclayout_user)
/* Get statistics about corrected/uncorrected errors */
#define ECCGETSTATS _IOR('M', 18, struct mtd_ecc_stats)
/* Set MTD mode on a per-file-descriptor basis (see "MTD file modes") */
#define MTDFILEMODE _IO('M', 19)
/* Erase segment of MTD (supports 64-bit address) */
#define MEMERASE64 _IOW('M', 20, struct erase_info_user64)
/* Write data to OOB (64-bit version) */
#define MEMWRITEOOB64 _IOWR('M', 21, struct mtd_oob_buf64)
/* Read data from OOB (64-bit version) */
#define MEMREADOOB64 _IOWR('M', 22, struct mtd_oob_buf64)
/* Check if chip is locked (for MTD that supports it) */
#define MEMISLOCKED _IOR('M', 23, struct erase_info_user)
/*
* Most generic write interface; can write in-band and/or out-of-band in various
* modes (see "struct mtd_write_req"). This ioctl is not supported for flashes
* without OOB, e.g., NOR flash.
*/
#define MEMWRITE _IOWR('M', 24, struct mtd_write_req)
/*
* Obsolete legacy interface. Keep it in order not to break userspace
* interfaces
*/
struct nand_oobinfo {
__u32 useecc;
__u32 eccbytes;
__u32 oobfree[8][2];
__u32 eccpos[32];
};
struct nand_oobfree {
__u32 offset;
__u32 length;
};
#define MTD_MAX_OOBFREE_ENTRIES 8
#define MTD_MAX_ECCPOS_ENTRIES 64
/*
* OBSOLETE: ECC layout control structure. Exported to user-space via ioctl
* ECCGETLAYOUT for backwards compatbility and should not be mistaken as a
* complete set of ECC information. The ioctl truncates the larger internal
* structure to retain binary compatibility with the static declaration of the
* ioctl. Note that the "MTD_MAX_..._ENTRIES" macros represent the max size of
* the user struct, not the MAX size of the internal struct nand_ecclayout.
*/
struct nand_ecclayout_user {
__u32 eccbytes;
__u32 eccpos[MTD_MAX_ECCPOS_ENTRIES];
__u32 oobavail;
struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES];
};
/**
* struct mtd_ecc_stats - error correction stats
*
* @corrected: number of corrected bits
* @failed: number of uncorrectable errors
* @badblocks: number of bad blocks in this partition
* @bbtblocks: number of blocks reserved for bad block tables
*/
struct mtd_ecc_stats {
__u32 corrected;
__u32 failed;
__u32 badblocks;
__u32 bbtblocks;
};
/*
* MTD file modes - for read/write access to MTD
*
* @MTD_FILE_MODE_NORMAL: OTP disabled, ECC enabled
* @MTD_FILE_MODE_OTP_FACTORY: OTP enabled in factory mode
* @MTD_FILE_MODE_OTP_USER: OTP enabled in user mode
* @MTD_FILE_MODE_RAW: OTP disabled, ECC disabled
*
* These modes can be set via ioctl(MTDFILEMODE). The mode mode will be retained
* separately for each open file descriptor.
*
* Note: %MTD_FILE_MODE_RAW provides the same functionality as %MTD_OPS_RAW -
* raw access to the flash, without error correction or autoplacement schemes.
* Wherever possible, the MTD_OPS_* mode will override the MTD_FILE_MODE_* mode
* (e.g., when using ioctl(MEMWRITE)), but in some cases, the MTD_FILE_MODE is
* used out of necessity (e.g., `write()', ioctl(MEMWRITEOOB64)).
*/
enum mtd_file_modes {
MTD_FILE_MODE_NORMAL = MTD_OTP_OFF,
MTD_FILE_MODE_OTP_FACTORY = MTD_OTP_FACTORY,
MTD_FILE_MODE_OTP_USER = MTD_OTP_USER,
MTD_FILE_MODE_RAW,
};
#endif /* __MTD_ABI_H__ */