Hi rdiez, On 11.01.2016 14:58, R. Diez wrote: > Hi all: > > I am trying to use flashrom with a fast generic FTDI FT2232H adapter as > an SPI Flash programmer in a small production line. Nice to here.
> > The SPI Flash chip can hold 8 MiB of data, but we are only using the > first 512 KiB of it. I guess, a very simple patch would be to change the size of the chip in flashchips.c. > I found flashrom to be surprisingly slow. I started digging and the step > "Reading old flash chip contents..." is taking minutes. It looks like > flashrom is reading the whole contents before writing anything at all. flashrom was designed with very low-latency internal programmers in mind. What makes it slow is the overhead for synchronous USB reads. This would help to reduce overall read times: http://www.flashrom.org/pipermail/flashrom/2015-August/013823.html (Needs to be enabled per chip in flashchips.c) > I am using 7.5 MHz at the moment. I cannot pump up the frequency too > much, as I am still using flywires to connect the SPI flash chip to the > programmer. With very short wires, I got my FT2232H up to the full 30MHz once... Also, sometimes I forget that 6 is a valid divisor between 8 and 4 :) > > I know that the flash chips are empty (0xFF), so flashrom does not need > to read anything beforehand. If it is going to read anything, the first > 512 KiB would suffice, because I am not touching anything else. There are some layout patches floating around that would do the trick. Yeah, more unmerged patches... > I found the following in the source code: > > int read_all_first = 1; /* FIXME: Make this configurable. */ > > I also found the following message about it: > > http://www.flashrom.org/pipermail/flashrom/2011-December/008440.html > > I guess the corresponding command-line argument is still missing. There is: http://www.flashrom.org/pipermail/flashrom/2015-December/014034.html Regards, Nico _______________________________________________ flashrom mailing list [email protected] http://www.flashrom.org/mailman/listinfo/flashrom
