AMD S3: Program the flash in a bigger data packet

According to spi.c in src/southbridge/amd/agesa/hudson
readwrite = (bytesin + readoffby1) << 4 | bytesout;
We can see that Hudson limits the SPI programming data
packet size as 15.

We used to write data to SPI in dword mode. It didn't
take full advantage of the data packet size. We need to
leverage that to speed up programming time.

Change-Id: I615e3c8e754e58702247bc26cfffbedaf5827ea8
Signed-off-by: Zheng Bao <zheng.bao@amd.com>
Signed-off-by: Zheng Bao <fishbaozi@gmail.com>
Reviewed-on: http://review.coreboot.org/2306
Tested-by: build bot (Jenkins)
Reviewed-by: Dave Frodin <dave.frodin@se-eng.com>
Reviewed-by: Martin Roth <martin.roth@se-eng.com>
1 file changed