[flashrom] Try add support for SST45LF010

[Stefan Tauner]

On Fri, 1 Aug 2014 16:17:17 +0200
The Raven <originalraven at hotmail.com> wrote:

> Hello,
> i have an SST45LF010 chip here (from a nvidia graphic card) and try to
> add support for it.
> 
> The log show me this:
> Probing for SST SST25LF020A, 256 kB: probe_spi_rems: id1 0x5f, id2 0xdf
> Probing for SST SST25LF040A, 512 kB: probe_spi_res2: id1 0xff, id2 0xff
> Probing for SST SST25LF080(A), 1024 kB: probe_spi_res2: id1 0xff, id2 0xff
> Probing for SST SST25VF512A, 64 kB: probe_spi_rems: id1 0x5f, id2 0xdf
> Probing for SST SST25VF010, 128 kB: probe_spi_rems: id1 0x5f, id2 0xdf
> Probing for SST SST25VF020, 256 kB: probe_spi_rems: id1 0x5f, id2 0xdf
> Probing for SST SST25VF020B, 256 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> Probing for SST SST25VF040, 512 kB: probe_spi_rems: id1 0x5f, id2 0xdf
> Probing for SST SST25VF040B, 512 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> Probing for SST SST25VF040B.REMS, 512 kB: probe_spi_rems: id1 0x5f, id2 0xdf
> Probing for SST SST25VF080B, 1024 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> Probing for SST SST25VF016B, 2048 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> Probing for SST SST25VF032B, 4096 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> Probing for SST SST25VF064C, 8192 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> Probing for SST SST25WF512, 64 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> Probing for SST SST25WF010, 128 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> Probing for SST SST25WF020, 256 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> Probing for SST SST25WF040, 512 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> Probing for SST SST25WF080, 1024 kB: RDID byte 1 parity violation.
> probe_spi_rdid_generic: id1 0x7fff, id2 0xff
> 
> So it looks that it works similar to the "SST25VF010".
> But it has (always) an ID of 0x5F! Normally SST chips have 0xBF.
> In the datasheet i can also see that this chip should have 0xBF.
> Looks strange to me. Why i get this strange ID? Is this possible?

Hi!

That indeed looks strange. I'd guess some kind of communication
problem, e.g. too long wires or other interference (is the chip still
soldered?). The first bit of the RDID reply also indicates that. Try
lowering the SPI frequency, adding terminator resistors and/or
shortening/optimizing the wires.
You should get 0xBF 0x42 for REMS and 0xFF... for all other SPI
probers. Oh that's actually wrong. The chip implements what's normally
the RDID opcode as RDSR (read status register). That may explain the
RDID response... at least partially :) And the other opcodes are also
not what to expect normally... like with its other SST45 relatives. That
complicates adding support for it even further...

-- 
Kind regards/Mit freundlichen Grüßen, Stefan Tauner