Hi Ken,
First of all, thanks for your quick response.
One of the first things I tried was to change the values of
MTD_SMART_SECTOR_SIZE [=2048] and MTD_SMART_SECTOR_CACHE_SIZE [=2048] but
the smartfs_mount() is still failing to validate the low-level format. For
reference the struct fs->fs_llformat has the following values just before
the error
fs->fs_llformat.sectorsize:2048
fs->fs_llformat.availbytes:2043
fs->fs_llformat.nsectors:16384
fs->fs_llformat.nfreesectors:16378
fs->fs_llformat.flags:0 '\000'
fs->fs_llformat.namesize:16 '\020'
Changing the capacity to W25_JEDEC_CAPACITY_128MBIT and keeping
MTD_SMART_SECTOR_SIZE and MTD_SMART_SECTOR_CACHE_SIZE the same [2048] the
file system works as expected. For reference the struct fs->fs_llformat has
the following values just before the function validates the low level
format.
fs->fs_llformat.sectorsize:2048
fs->fs_llformat.availbytes:2043
fs->fs_llformat.nsectors:8192
fs->fs_llformat.nfreesectors:8183
fs->fs_llformat.flags:1 '\001'
fs->fs_llformat.namesize:16 '\020'
Thanks
Daniel Pereira de Carvalho
Em qua., 19 de out. de 2022 às 21:26, Ken Pettit <petti...@gmail.com>
escreveu:
> Hi Daniel,
>
> The SmartFS FS *can* work with devices greater than 16M Bytes. I have
> used it with a 256MBit / 32M Byte SPI flash before quite successfully.
>
> But you have to ensure the logical sector size is large enough. One
> limitation of the SMART MTD (and therefore SMART FS) implementation is
> that it uses unsigned 16-bit integers for logical sector numbers. This
> means you can only have 65536 maximum logical sectors (actually a few
> less than that, but the code knows how to deal with 65536 values and
> simply "waste" a few reserved values like zero and 0xFFFF).
>
> This means that for a 32M byte flash, you would need to ensure the
> logical sector size is at least 32M / 65536 = 512 bytes. Typically for
> the SMART MTD layer, a logical sector size of 1024 or 2048 (or larger)
> is preferred because the code can manage erase blocks / free sector
> collection management better.
>
> In your 'make menuconfig', check your SMART logical sector size and try
> setting it to 2048. For the W25256JEVIEQ part with 256-byte pages,
> this will be 8 pages per logical sector, which is a good setting. Of
> course this also means that the smallest file size is 2K bytes, even if
> the file only has 1 byte stored in it. That's the price you pay for a
> structured file system though.
>
> Ken
>
>
> On 10/19/22 4:39 PM, Daniel Pereira Carvalho wrote:
> > Hi guys,
> >
> > I am trying to use the memory W25Q256JVEIQ, with SMARTS FS. To do it I
> > added the support for this memory in "drivers/mtd/w25.c". I just added
> the
> > code below
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > *..#define W25_JEDEC_CAPACITY_256MBIT 0x19 /* 8192x4096 = 256Mbit memory
> > capacity */../* 256M-bit / 32M-byte (33,554,432) * * W25Q256JV (Standard
> > SPI) */else if (capacity == W25_JEDEC_CAPACITY_256MBIT) {
> > priv->nsectors = NSECTORS_256MBIT; }..*
> >
> > The memory initialization seems to go well. I can run the mksmartfs
> > utility, mount and write to the filesystem. However when I reboot the
> board
> > I can't mount the filesystem again. The function smartfs_mount() returns
> > the error "ERROR: No low-level format found".
> >
> > The documentation says that SMARTS FS is designed to work with 1M byte to
> > 16M byte in size (though this is not a limitation). So I changed the
> > priv->nsectors from NSECTORS_256MBIT to NSECTORS_128MBIT to see if the
> > problem was with the size of the memory. After this change the file
> system
> > started to work as expected.
> >
> > Should SMARTS FS work with memories larger than 16M, since in the docs it
> > is said that this is not a limitation? If SMART FS is limited to memories
> > smaller than 16M do you recommend another filesystem?
> >
> > Thanks
> >
> > Daniel Pereira de Carvalho
> >
>
>
