Hi Jose,

and I do similar to you under romstage.c -> mainboard_early_init:

outb(0x55, 0x2e);

outb(0x05, 0x0a3f); /* GP50= RI_2 : in /

outb(0x05, 0x0a40); / GP51= DCD_2 : in /

outb(0x05, 0x0a41); / GP52= RXD_2 : in /

outb(0x04, 0x0a42); / GP53= TXD_2 : out /

outb(0x05, 0x0a43); / GP54= DSR_2 : in /

outb(0x04, 0x0a44); / GP55= RTS_2 : out /

outb(0x05, 0x0a45); / GP56= CTS_2 : in /

outb(0x04, 0x0a46); / GP57= DTR_2 : out */outb(0xaa, 0x2e);

but It doesn't work.

Also I set the same code under mainboard.c -> mainboard_init but

neither work.

You should not copy my code for the two major reasons:

1. SCH5545 and SCH3114 are very different.
   
2. GPIO configuration on SCH5545 is not accessible from SuperIO. The
   

   code I have written communicates with Environmental Controller (ARC
   

   coprocessor) which resides inside the SCH5545, because only the EC had
   

   access to those registers. The SCH5545 did not have GPIO config
   

   registers in the Runtime Registers block.
   
   This will obviously not work.
   

Any advice on this? because I cannot find any information on the

datasheet on how to set those registers and I suppose I just have to

set to the 0xa00 base address + register.

I suggest to look at TABLE 26-3 in the datasheet of your part

http://ww1.microchip.com/downloads/en/DeviceDoc/00001872A.pdf

and using these runtime registers definitions, write the right code that

will set the GPIOs up for UARTs.  Just use the appropriate 0xa00 base +

REG OFFSET from the table and you should be allright. For simplicity you

may also compare these registers to reference values from original

firmware (but with care! sometimes firmware vendors tend to make stupid

mistakes).

Thank you,

Jose Trujillo.

Best regards,

---

Michał Żygowski

Firmware Engineer

https://3mdeb.com | @3mdeb_com

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