On 11/5/10 12:19 AM, Bao, Zheng wrote:
According to the description in datasheet of f71889,
"To enable configuration, the entry key 0x87 must be written to the index port"
" -o 4e 87 -o 4e 87 (enable configuration) -o 4e aa (disable configuration) " This piece of text appears in most of the datasheet of fintek superio. It doesnt say it quite clear, but it seems that the 0x87 should be written twice. I tried on f81865, which is not in the coreboot tree yet. If the 0x87 is only written once, you can only R/W the index/data port once. All the subsequent RW will fail. Writing twice will be ok.
Plus, in the superiotool, the function enter_conf_mode_winbond_fintek_ite_8787 also write 8787.
The fintek superio chips seem to enable the UART automatically when the power is on. So I didnt find it failed to access.
Signed-off-by: Zheng Bao zheng.bao@amd.com
Acked-by: Stefan Reinauer stepan@coreboot.org
Stefan