mtd: nand: omap: add CONFIG_NAND_OMAP_ECCSCHEME for selection of ecc-scheme

This patch adds new CONFIG_NAND_OMAP_ECCSCHEME, replacing other distributed
CONFIG_xx used for selecting NAND ecc-schemes.
This patch aims at solving following issues.

1) Currently ecc-scheme is tied to SoC platform, which prevents user to select
   other ecc-schemes also supported in hardware. like;
 - most of OMAP3 SoC platforms use only 1-bit Hamming ecc-scheme, inspite
   the fact that they can use higher ecc-schemes like 8-bit ecc-schemes with
   software based error detection (OMAP_ECC_BCH4_CODE_HW_DETECTION_SW).
 - most of AM33xx SoC plaforms use 8-bit BCH ecc-scheme for now, but hardware
   supports BCH16 ecc-scheme also.

2) Different platforms use different CONFIG_xx to select ecc-schemes, which
   adds confusion for user while migrating platforms.
 - *CONFIG_NAND_OMAP_ELM* which enables ELM hardware engine, selects only
    8-bit BCH ecc-scheme with h/w based error-correction (OMAP_ECC_BCH8_CODE_HW)
    whereas ELM hardware engine supports other ecc-schemes also like; BCH4,
    and BCH16 (in future).
 - *CONFIG_NAND_OMAP_BCH8* selects 8-bit BCH ecc-scheme with s/w based error
    correction (OMAP_ECC_BCH8_CODE_HW_DETECTION_SW).
 - *CONFIG_SPL_NAND_SOFTECC* selects 1-bit Hamming ecc-scheme using s/w library

Thus adding new *CONFIG_NAND_OMAP_ECCSCHEME* de-couples ecc-scheme dependency
on SoC platform and NAND driver. And user can select ecc-scheme independently
foreach board.
However, selection some hardware based ecc-schemes (OMAP_ECC_BCHx_CODE_HW) still
depends on presence of ELM hardware engine on SoC. (Refer doc/README.nand)

Signed-off-by: Pekon Gupta <pekon@ti.com>
This commit is contained in:
pekon gupta 2013-11-18 19:03:01 +05:30 committed by Scott Wood
parent d016dc42ce
commit 3f719069c8
17 changed files with 43 additions and 15 deletions

View file

@ -208,6 +208,29 @@ Platform specific options
detection. However ECC calculation on such plaforms would still be
done by GPMC controller.
CONFIG_NAND_OMAP_ECCSCHEME
On OMAP platforms, this CONFIG specifies NAND ECC scheme.
It can take following values:
OMAP_ECC_HAM1_CODE_SW
1-bit Hamming code using software lib.
(for legacy devices only)
OMAP_ECC_HAM1_CODE_HW
1-bit Hamming code using GPMC hardware.
(for legacy devices only)
OMAP_ECC_BCH4_CODE_HW_DETECTION_SW
4-bit BCH code (unsupported)
OMAP_ECC_BCH4_CODE_HW
4-bit BCH code (unsupported)
OMAP_ECC_BCH8_CODE_HW_DETECTION_SW
8-bit BCH code with
- ecc calculation using GPMC hardware engine,
- error detection using software library.
- requires CONFIG_BCH to enable software BCH library
(For legacy device which do not have ELM h/w engine)
OMAP_ECC_BCH8_CODE_HW
8-bit BCH code with
- ecc calculation using GPMC hardware engine,
- error detection using ELM hardware engine.
NOTE:
=====

View file

@ -161,8 +161,7 @@ BCH8
To enable hardware assisted BCH8 (8-bit BCH [Bose, Chaudhuri, Hocquenghem]) on
OMAP3 devices we can use the BCH library in lib/bch.c. To do so add CONFIG_BCH
to enable the library and CONFIG_NAND_OMAP_BCH8 to to enable hardware assisted
syndrom generation to your board config.
and set CONFIG_NAND_OMAP_ECCSCHEME=5 (refer README.nand) for selecting BCH8_SW.
The NAND OOB layout is the same as in linux kernel, if the linux kernel BCH8
implementation for OMAP3 works for you so the u-boot version should also.
When you require the SPL to read with BCH8 there are two more configs to

View file

@ -1004,18 +1004,13 @@ int board_nand_init(struct nand_chip *nand)
nand->ecc.layout = &omap_ecclayout;
/* select ECC scheme */
#if defined(CONFIG_NAND_OMAP_ELM)
err = omap_select_ecc_scheme(nand, OMAP_ECC_BCH8_CODE_HW,
#if defined(CONFIG_NAND_OMAP_ECCSCHEME)
err = omap_select_ecc_scheme(nand, CONFIG_NAND_OMAP_ECCSCHEME,
CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE);
#elif defined(CONFIG_NAND_OMAP_BCH8)
err = omap_select_ecc_scheme(nand, OMAP_ECC_BCH8_CODE_HW_DETECTION_SW,
CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE);
#elif !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_NAND_SOFTECC)
#else
/* pagesize and oobsize are not required to configure sw ecc-scheme */
err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_SW,
0, 0);
#else
err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_HW,
CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE);
#endif
if (err)
return err;

View file

@ -240,7 +240,8 @@
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 14
#define CONFIG_SYS_NAND_ONFI_DETECTION
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_BCH8_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE
#define CONFIG_SYS_NAND_U_BOOT_OFFS 0x80000
#endif

View file

@ -264,6 +264,7 @@
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 14
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_BCH8_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE

View file

@ -340,6 +340,7 @@
10, 11, 12, 13}
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 3
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE
#define CONFIG_SYS_NAND_U_BOOT_OFFS 0x80000

View file

@ -334,6 +334,7 @@
10, 11, 12, 13}
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 3
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE
#define CONFIG_SYS_NAND_U_BOOT_OFFS 0x80000

View file

@ -327,6 +327,7 @@
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 3
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE

View file

@ -353,7 +353,6 @@
#define CONFIG_SPL_FRAMEWORK
#define CONFIG_SPL_BOARD_INIT
#define CONFIG_SPL_NAND_SIMPLE
#define CONFIG_SPL_NAND_SOFTECC
#define CONFIG_SPL_LIBCOMMON_SUPPORT
#define CONFIG_SPL_LIBDISK_SUPPORT
@ -395,6 +394,7 @@
56, 57, 58, 59, 60, 61, 62, 63}
#define CONFIG_SYS_NAND_ECCSIZE 256
#define CONFIG_SYS_NAND_ECCBYTES 3
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_SW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE

View file

@ -432,6 +432,7 @@
10, 11, 12, 13}
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 3
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE
#define CONFIG_SYS_NAND_U_BOOT_OFFS 0x80000

View file

@ -107,6 +107,7 @@
10, 11, 12, 13}
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 3
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE
#define CONFIG_SYS_NAND_U_BOOT_OFFS 0x80000

View file

@ -86,6 +86,7 @@
10, 11, 12, 13}
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 3
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE
#define CONFIG_SYS_NAND_U_BOOT_OFFS 0x80000

View file

@ -362,6 +362,7 @@
10, 11, 12, 13}
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 3
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE
#define CONFIG_SYS_NAND_U_BOOT_OFFS 0x80000
#endif

View file

@ -325,6 +325,7 @@
10, 11, 12, 13}
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 3
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE
#define CONFIG_SYS_NAND_U_BOOT_OFFS 0x80000

View file

@ -196,6 +196,7 @@
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 14
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_BCH8_CODE_HW
#define CONFIG_SYS_NAND_ECCSTEPS 4
#define CONFIG_SYS_NAND_ECCTOTAL (CONFIG_SYS_NAND_ECCBYTES * \

View file

@ -225,7 +225,6 @@
#define CONFIG_SPL_BOARD_INIT
#define CONFIG_SPL_CONSOLE
#define CONFIG_SPL_NAND_SIMPLE
#define CONFIG_SPL_NAND_SOFTECC
#define CONFIG_SPL_NAND_WORKSPACE 0x8f07f000 /* below BSS */
#define CONFIG_SPL_LIBCOMMON_SUPPORT
@ -262,6 +261,7 @@
56, 57, 58, 59, 60, 61, 62, 63}
#define CONFIG_SYS_NAND_ECCSIZE 256
#define CONFIG_SYS_NAND_ECCBYTES 3
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_SW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE

View file

@ -138,7 +138,6 @@
#define CONFIG_SYS_MAX_NAND_DEVICE 1 /* Max number of NAND */
/* devices */
#define CONFIG_NAND_OMAP_BCH8
#define CONFIG_BCH
#define CONFIG_SYS_NAND_MAX_OOBFREE 2
#define CONFIG_SYS_NAND_MAX_ECCPOS 56
@ -376,6 +375,7 @@
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 13
#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_BCH8_CODE_HW_DETECTION_SW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE