RE: [U-Boot-Users] Serial Port Configuration on MPC8xx
Hi
Is there something clean to do under Uboot to make it
configure SMC2 ?
Why should U-Boot initialize a port it does not use?
Where should this init done ?
This should be done, and actually it _is_ done, in the Linux UART driver. No help from U-Boot needed here.
Ummm... what exactly is the problem?
Hum I think that I don't understand something. In fact when I change the baudrate of SMC1 in UBoot, I see that the same baudrate remains used in the linux console ( am I getting mad ?? :-)) ) So I thought that the IO Connfiguration & The BRG settings was done only by UBoot. BTW, depending on the hardware the IO pins ( and the IO Config ) are not the same and nothing in the linux config allow to choose that... So it should mean that the Linux Uart Driver should be patched depending on your hardware.
Chris
In message D96E2AFA0DF3D211B139009027454948034CBEB1@helios.gnv.tcc.thomson-csf.com you wrote:
In fact when I change the baudrate of SMC1 in UBoot, I see that the same baudrate remains used in the linux console ( am I getting mad ?? :-)) )
This is just lucky coincidence if you happen to use the same serial port for cosole in U-Boot and Linux. Normally, you will have to pass the required information to the Linux kernel as a boot argument, like "console=ttyS2,115200"
So I thought that the IO Connfiguration & The BRG settings was done only by UBoot.
No, the philosophy is that each part of the software, each driver, is responsible to initialize the hardware it accesses. So the LInux UART driver will initialize the serial port(s) itself.
BTW, depending on the hardware the IO pins ( and the IO Config ) are not the same and nothing in the linux config allow to choose that... So it should
There are some de-facto standard configurations, which are supported by the Linux driver.
mean that the Linux Uart Driver should be patched depending on your hardware.
Indeed. If your hardware guys decided to build some different confi- guration, this may require to add some #ifdef's to the Linux kernel code. If you have a look at the UART drivers in our kernel treee you will see what I mean :-(
Best regards,
Wolfgang Denk
participants (2)
-
Christophe.LINDHEIMER＠fr.thalesgroup.com -
Wolfgang Denk