On Friday, February 26, 2016, <victorascroft@xxxxxxxxx> wrote:
Hi,
On 16-02-26 00:55:40, Woody Wu wrote:
> Hi,
>
> It seems, at least in 4.4.2 kernel, earlyprintk parameter supports
> something like 's3c24xx,<addr>'. But I dont know where to find out the addr
> value of the first uart port on my *s3c2416* based board. Can someone
> please tell me?
>
> Also, I desire to know if the earlycon parameter supports the Samsung
> S3C24xx uarts, if so, what should the value of the parameter look like?
Have a look in the documentation here
https://www.kernel.org/doc/Documentation/kernel-parameters.txt
The kernels kernel-parameter.txt documentation file lists the supported drivers.
Generally the UART0 port is used for debugging but I guess there is
no such hard and fast rule.
For your particular board, you can check which UART port is used
as the debug serial console and then get the address for the concerned
UART by checking the relevant dtsi file in
arch/arm/boot/dts/s3c24xx.dtsi or perhaps one of the exynosX.dtsi files?
UART0 port seems to have address of 0x50000000?
Regards,
Sanchayan.
Thanks for you pointing me to the dtsi files, very informational ! And, yes, the uart0 address os 0x50000000 and I has made it work via 'earlyprintk=serial,0x50000000,115200'. By the way, is this a physical address or mmap-ed address?
>
> Thank in advance,
>
> -woody
>
>
> --
> Life is the only flaw in an otherwise perfect nonexistence
> -- Schopenhauer
>
> woody
> public key at http://subkeys.pgp.net:11371 (narkewoody@xxxxxxxxx)
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies@xxxxxxxxxxxxxxxxx
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
--
Life is the only flaw in an otherwise perfect nonexistence
-- Schopenhauer
woody
public key at http://subkeys.pgp.net:11371 (narkewoody@xxxxxxxxx)
_______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
