[flashrom] [PATCH/FULL/SVN] Support for 4-bytes addressing SPI flash chips 32MB+ (256Mb+)
Aleksandr.Amelkin at t-platforms.ru
Fri Jan 16 10:19:11 CET 2015
> > > Flashrom is slow because read and erase operations are written very
> > > slow now. They could be easily changed to become faster in times or
> > > in 10s of times. Probably I'll do this later. This should be another patch.
> > I'll try to describe where these issues are...
> > The read issue is in spi_read_chunked. There is a loop that reads data
> > by pages (normally by 256 bytes). So, to read 32 MB flash we'll send
> > 131k read commands with 3-7 ms wait for each.
> Everything you say is true and optimizations you propose would be very
> helpful, but the main question is - what introduces this 3-7ms delays. That is
> NOT flashrom, nor it is libfti, nor libusb. The flash chips also don't seem to
> require millisecond delays for READ/READ4B commands.
Speaking of optimizations, another thing that could greatly help would be
adding support for DPI and QPI modes.
With best regards -
More information about the flashrom