Does anybody know when and how cyg_flash_devtab[] array is filled in? I see &(syg_flashdevtab[0]) == &syg_flashdevtab_end and syg_flashdevtab[0].num_block_infos < 0 whereas SYGHWR_IO_FLASH_DEVICE == 1

It is automatically filled in using the DEVTAB_ENTRY macro. I suggest reading this chapter (and the ones around it) about writing drivers for eCos: http://www.ecoscentric.com/ecospro/doc/html/ref/io-how-to-write-a-driver.html

I am afraid your link is a copy of http://ecos.sourceware.org/docs-3.0/ref/io-how-to-write-a-driver.html and there seems to be an error in DEVIO_TABLE calling: seeing devtab.h, it should be DEVIO_TABLE(l, write, read, select, get_config, set_config), they omitted select. I wrote DEVIO_TABLE( p8p_handlers, p8p_write, p8p_read, p8p_select, p8p_get_config, p8p_set_config, p8p_close ); DEVTAB_ENTRY( p8p_label, p8p_name, 0, //does not depend upon a lower level interface &p8p_handlers, p8p_init, p8p_lookup, p8p_priv ); and cdl_package CYGPKG_DEVS_FLASH_P8P { display "P8P FLASHlike memory support" parent CYGPKG_IO_FLASH description "FLASHlike memory device support for P8P" implements CYGHWR_IO_FLASH_DEVICE hardware compile p8p.c } in .cdl. It is built alright but cyg_flash_devtab does not seem to be filled in.

Yes, the DEVTAB_ENTRY macro will only fill in the generic devtab, which holds any kind of driver accessible with the generic API. eCos also has specific device tables for special kind of peripherals, such as for example cyg_flashdevtab for flash devices. Those tables need dedicated macros to be filled correctly. In that case if you can't find the documentation, it is a good idea to check the include files of the generic package. For example in your case, in the CYGPKG_IO_FLASH package, you'll find with the following macros in packages/io/flash/current/include/flash_dev.h (on my old version of eCos, so yours my differ a little):// Macros for instantiating the above structures. # ifdef CYGHWR_IO_FLASH_BLOCK_LOCKING # define CYG_FLASH_FUNS(_funs_, _init_, _query_ , _erase_, _prog_ , _read_, _lock_, _unlock_) struct cyg_flash_dev_funs _funs_ = { .flash_init = _init_, .flash_query = _query_, .flash_erase_block = _erase_, .flash_program = _prog_, .flash_read = _read_, .flash_block_lock = _lock_, .flash_block_unlock = _unlock_ } # else # define CYG_FLASH_FUNS(_funs_, _init_, _query_ , _erase_, _prog_ , _read_, _lock_, _unlock_) struct cyg_flash_dev_funs _funs_ = { .flash_init = _init_, .flash_query = _query_, .flash_erase_block = _erase_, .flash_program = _prog_, .flash_read = _read_ } # endif // We assume HAL tables are placed into RAM. # define CYG_FLASH_DRIVER(_name_, _funs_, _flags_, _start_, _end_, _num_block_infos_, _block_info_, _priv_) struct cyg_flash_dev _name_ CYG_HAL_TABLE_ENTRY(cyg_flashdev) = { .funs = _funs_, .flags = _flags_, .start = _start_, .end = _end_, .num_block_infos = _num_block_infos_, .block_info = _block_info_, .priv = _priv_ }

no this should be enough... are you sure that your custom driver is included in the eCos configuration? Could there be a# ifdef somewhere that prevents those macros from running? An easy way I have to find out if a specific part of the source code is compiled, is to voluntarily introduce a syntax error just before of after those macros. If you can still compile eCos without any errors, then it means that your code isn't compiled, or ignored. AFAIK the CYG_FLASH_DRIVER inserts an element statically in the code, during compile time, so there is no reason why the table wouldn't be populated. Are you looking at the correct table? From what I'm seeing, the table used by those macros is cyg_flashdev, not cyg_flash_devtab

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Altera_Forum

Honored Contributor

12 years ago

Filling in cyg_flash_devtab[] array

Does anybody know when and how cyg_flash_devtab[] array is filled in? I see &(syg_flashdevtab[0]) == &syg_flashdevtab_end and syg_flashdevtab[0].num_block_infos < 0 whereas SYGHWR_IO_FLASH_DEVICE == 1

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Altera_Forum
Honored Contributor
12 years ago
It's just that this is an Altera forum, and the eCos section here is more specifically about the Nios II port of eCos. If you are using a PowerPC board you'll probably have more luck on a more generic eCos forum or mailing list, or maybe on a PowerPC forum.

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Filling in cyg_flash_devtab[] array

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