MTD wrapper for emulated MTD devices

MTD device that is emulated in RAM for test purposes. More...

Detailed Description

MTD device that is emulated in RAM for test purposes.

Helpers for using emulated MTDs.

The emulated MTD reproduces the programming behavior of a NOR flash. Programming a location can only clear bits, it can never set a bit from 0 back to 1. The sector a location belongs to has to be erased for that.

Modern NOR flash devices may even prohibit writing to a location that has not been erased before. This behavior is not emulated by this driver.

Author

Gunar Schorcht gunar.nosp@m.@sch.nosp@m.orcht.nosp@m..net

Data Structures
struct	mtd_emulated_t
	Device descriptor for a MTD device that is emulated in RAM. More...

Macros
#define	MTD_EMULATED_DEV(n, sc, pps, ps)
	Macro to define an emulated MTD.
#define	MTD_EMULATED_DEV_FS(n, m, fs)
	Macro to define an automatic VFS mount point for an emulated MTD.

Variables
const mtd_desc_t	_mtd_emulated_driver
	Emulated MTD device operations table for mtd.

Macro Definition Documentation

MTD_EMULATED_DEV

#define MTD_EMULATED_DEV	(		n,
			sc,
			pps,
			ps )

Value:

    uint8_t _mtd_emulated_memory ## n[sc * pps * ps];   \
                                                        \
    mtd_emulated_t mtd_emulated_dev ## n = {            \
        .base = {                                       \
            .driver = &_mtd_emulated_driver,            \
            .sector_count = sc,                         \
            .pages_per_sector = pps,                    \
            .page_size = ps,                            \
            .write_size = 1,                            \
        },                                              \
        .size = sc * pps * ps,                          \
        .memory = _mtd_emulated_memory ## n,            \
        .init_done = false,                             \
    };                                                  \
                                                        \
    XFA_CONST(mtd_dev_t, mtd_dev_xfa, 99) CONCAT(*mtd_emulated, n) = (mtd_dev_t *)&mtd_emulated_dev ## n

Macro to define an emulated MTD.

This macro creates a MTD device that is emulated in RAM. For example, using

MTD_EMULATED_DEV(0, 16, 4, 64)

creates the emulated MTD device mtd_emulated_dev0 with 16 sectors, 4 pages per sector and a page size of 64 bytes. The write size is always 1 byte.

Note

The emulated devices are added to the XFA of MTD device pointers mtd_dev_xfa with priority 99 to place them at the end of the XFA.

Parameters

n	index of the emulated MTD (results into symbol mtd_emulated_dev<n>)
sc	sectors of the emulated MTD
pps	pages per sector of the emulated MTD
ps	page size in bytes

Definition at line 54 of file mtd_emulated.h.

MTD_EMULATED_DEV_FS

#define MTD_EMULATED_DEV_FS	(		n,
			m,
			fs )

Value:

    VFS_AUTO_MOUNT(fs, VFS_MTD(mtd_emulated_dev ## n), "/mtde" # n, m)

Macro to define an automatic VFS mount point for an emulated MTD.

For example, using

MTD_EMULATED_DEV_FS(0, 2, fatfs);

automatically mounts the emulated MTD mtd_emulated_dev0 with FAT file system under mount point /mtde0 with unique index 2.

Parameters

n	index of the emulated MTD (symbol mtd_emulated_dev<n>, mount point /mtde0)
m	unique overall index of VFS mount point
fs	filesystem type used

Definition at line 87 of file mtd_emulated.h.