[coreboot] SST25VF016B (2MB) flash on m57sli (IT8716F).

Ward Vandewege ward at gnu.org
Thu Jan 17 02:48:45 CET 2008


Hi Ronald,

On Thu, Jan 17, 2008 at 12:13:48AM +0100, Ronald Hoogenboom wrote:
> Problem1 (for reading) is solved by NOT using the mmap method for
> reading the flash contents, but using outb() for sending the flash read
> commands (using a specific 25vf016 read function). Also the normal read
> command is only supported up to 25MHz by this chip, so I cannot use the
> 33MHz speed as used normally by spi.c. There is also a 'high speed' read
> command (0x0b), which inserts an extra dummy byte between address and
> data, but as the 8716 only allows max. 3 bytes read per io transfer, the
> gain (3 bytes per io transfer @ 16MHz versus 2 bytes per io transfer @
> 33MHz) is negligible.

Can you elaborate a bit about that - I see the two read speeds in the
datasheet, but how do you get to 16MHz in that last sentence?

Thanks,
Ward.

-- 
Ward Vandewege <ward at fsf.org>
Free Software Foundation - Senior System Administrator




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