Lines Matching +full:nand +full:- +full:ecc +full:- +full:placement
2 MTD NAND Driver Programming Interface
10 The generic NAND driver supports almost all NAND and AG-AND based chips
15 board drivers or filesystem drivers suitable for NAND devices.
31 --------------------------
37 - [MTD Interface]
43 - [NAND Interface]
45 These functions are exported and provide the interface to the NAND
48 - [GENERIC]
53 - [DEFAULT]
58 via pointers in the NAND chip description structure. The board driver
65 -------------------------------
71 - [INTERN]
73 These members are for NAND driver internal use only and must not be
77 - [REPLACEABLE]
86 - [BOARDSPECIFIC]
92 - [OPTIONAL]
95 The generic NAND driver code does not use this information.
101 functions and fill out some really board dependent members in the nand
105 -------------
109 using kmalloc or you can allocate it statically. The NAND chip structure
131 -----------------
150 -------------------------
153 NAND chip(s). The access can be done by GPIO pins or by address lines.
183 case NAND_CTL_SETCLE: this->legacy.IO_ADDR_W |= CLE_ADRR_BIT; break;
184 case NAND_CTL_CLRCLE: this->legacy.IO_ADDR_W &= ~CLE_ADRR_BIT; break;
185 case NAND_CTL_SETALE: this->legacy.IO_ADDR_W |= ALE_ADRR_BIT; break;
186 case NAND_CTL_CLRALE: this->legacy.IO_ADDR_W &= ~ALE_ADRR_BIT; break;
192 ---------------------
194 If the hardware interface has the ready busy pin of the NAND chip
200 and the function pointer this->legacy.dev_ready is set to NULL.
203 -------------
222 printk ("Unable to allocate NAND MTD device structure.\n");
223 err = -ENOMEM;
232 printk("Ioremap to access NAND chip failed\n");
233 err = -EIO;
237 /* Set address of NAND IO lines */
238 this->legacy.IO_ADDR_R = baseaddr;
239 this->legacy.IO_ADDR_W = baseaddr;
241 this->hwcontrol = board_hwcontrol;
243 this->legacy.chip_delay = CHIP_DEPENDEND_COMMAND_DELAY;
245 this->legacy.dev_ready = board_dev_ready;
246 this->eccmode = NAND_ECC_SOFT;
250 err = -ENXIO;
268 -------------
297 This chapter describes the advanced functionality of the NAND driver.
302 ---------------------
304 The nand driver can control chip arrays. Therefore the board driver must
311 The nand driver concatenates the chips to one virtual chip and provides
341 this->legacy.IO_ADDR_R &= ~BOARD_NAND_ADDR_MASK;
342 this->legacy.IO_ADDR_W &= ~BOARD_NAND_ADDR_MASK;
345 this->legacy.IO_ADDR_R |= BOARD_NAND_ADDR_CHIP0;
346 this->legacy.IO_ADDR_W |= BOARD_NAND_ADDR_CHIP0;
350 this->legacy.IO_ADDR_R |= BOARD_NAND_ADDR_CHIPn;
351 this->legacy.IO_ADDR_W |= BOARD_NAND_ADDR_CHIPn;
357 Hardware ECC support
358 --------------------
363 The nand driver supports three different types of hardware ECC.
365 - NAND_ECC_HW3_256
367 Hardware ECC generator providing 3 bytes ECC per 256 byte.
369 - NAND_ECC_HW3_512
371 Hardware ECC generator providing 3 bytes ECC per 512 byte.
373 - NAND_ECC_HW6_512
375 Hardware ECC generator providing 6 bytes ECC per 512 byte.
377 - NAND_ECC_HW8_512
379 Hardware ECC generator providing 8 bytes ECC per 512 byte.
386 - enable_hwecc
393 - calculate_ecc
396 Transfer the ECC from the hardware to the buffer. If the option
400 - correct_data
402 In case of an ECC error this function is called for error detection
404 corrected. If the error is not correctable return -1. If your
409 Hardware ECC with syndrome calculation
412 Many hardware ECC implementations provide Reed-Solomon codes and
414 standard Reed-Solomon syndrome before calling the error correction code
415 in the generic Reed-Solomon library.
417 The ECC bytes must be placed immediately after the data bytes in order
419 layout used by software ECC. The separation of data and out of band area
420 is not longer possible. The nand driver code handles this layout and the
422 code. Provide a matching oob-layout in this case. See rts_from4.c and
424 use bad block tables on FLASH, because the ECC layout is interfering
429 -----------------------
431 Most NAND chips mark the bad blocks at a defined position in the spare
438 The nand driver supports various types of bad block tables.
440 - Per device
445 - Per chip
450 - Fixed offset
455 - Automatic placed
460 - Mirrored tables
478 AG-AND chips this is mandatory, as they have no factory marked bad
493 nand chip structure before calling nand_scan(). For AG-AND chips is
495 table functionality of the NAND driver. The default bad block table
498 - Store bad block table per chip
500 - Use 2 bits per block
502 - Automatic placement at the end of the chip
504 - Use mirrored tables with version numbers
506 - Reserve 4 blocks at the end of the chip
523 - Number of bits per block
527 - Table per chip
533 - Table location is absolute
542 - Table location is automatically detected
554 - Table creation
560 - Table write support
571 - Table version control
582 - Save block contents on write
591 - Number of reserved blocks
593 For automatic placement some blocks must be reserved for bad block
600 Spare area (auto)placement
601 --------------------------
603 The nand driver implements different possibilities for placement of
606 - Placement defined by fs driver
608 - Automatic placement
610 The default placement function is automatic placement. The nand driver
611 has built in default placement schemes for the various chiptypes. If due
612 to hardware ECC functionality the default placement does not fit then
613 the board driver can provide a own placement scheme.
615 File system drivers can provide a own placement scheme which is used
616 instead of the default placement scheme.
618 Placement schemes are defined by a nand_oobinfo structure
630 - useecc
632 The useecc member controls the ecc and placement function. The header
633 file include/mtd/mtd-abi.h contains constants to select ecc and
634 placement. MTD_NANDECC_OFF switches off the ecc complete. This is
636 MTD_NANDECC_PLACE selects caller defined placement,
637 MTD_NANDECC_AUTOPLACE selects automatic placement.
639 - eccbytes
641 The eccbytes member defines the number of ecc bytes per page.
643 - eccpos
646 ecc codes are placed.
648 - oobfree
651 used for automatic placement. The information is given in the format
656 Placement defined by fs driver
660 which defines the ecc placement. For writes the caller must provide a
663 is (number of pages) \* ((size of spare area) + (number of ecc steps per
664 page) \* sizeof (int)). The driver stores the result of the ecc check
667 <spare data page 0><ecc result 0>...<ecc result n>
671 <spare data page n><ecc result 0>...<ecc result n>
675 If the spare area buffer is NULL then only the ECC placement is done
678 Automatic placement argument
681 Automatic placement uses the built in defaults to place the ecc bytes in
687 If the spare area buffer is NULL then only the ECC placement is done
691 ----------------------------------------
699 0x00 ECC byte 0 Error correction code byte 0
700 0x01 ECC byte 1 Error correction code byte 1
701 0x02 ECC byte 2 Error correction code byte 2
719 0x00 ECC byte 0 Error correction code byte 0 of the lower
721 0x01 ECC byte 1 Error correction code byte 1 of the lower
723 0x02 ECC byte 2 Error correction code byte 2 of the lower
725 0x03 ECC byte 3 Error correction code byte 0 of the upper
732 0x06 ECC byte 4 Error correction code byte 1 of the upper
734 0x07 ECC byte 5 Error correction code byte 2 of the upper
736 0x08 - 0x0F Autoplace 0 - 7
750 0x02-0x27 Autoplace 0 - 37
751 0x28 ECC byte 0 Error correction code byte 0 of the first
753 0x29 ECC byte 1 Error correction code byte 1 of the first
755 0x2A ECC byte 2 Error correction code byte 2 of the first
757 0x2B ECC byte 3 Error correction code byte 0 of the second
759 0x2C ECC byte 4 Error correction code byte 1 of the second
761 0x2D ECC byte 5 Error correction code byte 2 of the second
763 0x2E ECC byte 6 Error correction code byte 0 of the third
765 0x2F ECC byte 7 Error correction code byte 1 of the third
767 0x30 ECC byte 8 Error correction code byte 2 of the third
769 0x31 ECC byte 9 Error correction code byte 0 of the fourth
771 0x32 ECC byte 10 Error correction code byte 1 of the fourth
773 0x33 ECC byte 11 Error correction code byte 2 of the fourth
775 0x34 ECC byte 12 Error correction code byte 0 of the fifth
777 0x35 ECC byte 13 Error correction code byte 1 of the fifth
779 0x36 ECC byte 14 Error correction code byte 2 of the fifth
781 0x37 ECC byte 15 Error correction code byte 0 of the sixth
783 0x38 ECC byte 16 Error correction code byte 1 of the sixth
785 0x39 ECC byte 17 Error correction code byte 2 of the sixth
787 0x3A ECC byte 18 Error correction code byte 0 of the seventh
789 0x3B ECC byte 19 Error correction code byte 1 of the seventh
791 0x3C ECC byte 20 Error correction code byte 2 of the seventh
793 0x3D ECC byte 21 Error correction code byte 0 of the eighth
795 0x3E ECC byte 22 Error correction code byte 1 of the eighth
797 0x3F ECC byte 23 Error correction code byte 2 of the eighth
804 The NAND driver provides all necessary functions for a filesystem via
807 Filesystems must be aware of the NAND peculiarities and restrictions.
808 One major restrictions of NAND Flash is, that you cannot write as often
810 it again, are restricted to 1-3 writes, depending on the manufacturers
813 Therefore NAND aware filesystems must either write in page size chunks
815 pagesize. Available NAND aware filesystems: JFFS2, YAFFS.
818 area placement functionality which is described in one of the earlier
824 The MTD project provides a couple of helpful tools to handle NAND Flash.
826 - flasherase, flasheraseall: Erase and format FLASH partitions
828 - nandwrite: write filesystem images to NAND FLASH
830 - nanddump: dump the contents of a NAND FLASH partitions
832 These tools are aware of the NAND restrictions. Please use those tools
833 instead of complaining about errors which are caused by non NAND aware
843 ---------------------
848 These constants are defined in rawnand.h. They are OR-ed together to
870 These constants are defined in rawnand.h. They are OR-ed together to
873 /* The hw ecc generator provides a syndrome instead a ecc value on read
874 * This can only work if we have the ecc bytes directly behind the
875 * data bytes. Applies for DOC and AG-AND Renesas HW Reed Solomon generators */
879 ECC selection constants
880 -----------------------
882 Use these constants to select the ECC algorithm::
884 /* No ECC. Usage is not recommended ! */
886 /* Software ECC 3 byte ECC per 256 Byte data */
888 /* Hardware ECC 3 byte ECC per 256 Byte data */
890 /* Hardware ECC 3 byte ECC per 512 Byte data */
892 /* Hardware ECC 6 byte ECC per 512 Byte data */
894 /* Hardware ECC 8 byte ECC per 512 Byte data */
899 ----------------------------------
923 ---------------------------------
956 which are used in the NAND driver and might be relevant for a driver
961 .. kernel-doc:: include/linux/mtd/rawnand.h
967 This chapter contains the autogenerated documentation of the NAND kernel
972 .. kernel-doc:: drivers/mtd/nand/raw/nand_base.c
978 This chapter contains the autogenerated documentation of the NAND driver
984 .. kernel-doc:: drivers/mtd/nand/raw/nand_base.c
987 .. kernel-doc:: drivers/mtd/nand/raw/nand_bbt.c
993 The following people have contributed to the NAND driver: