[U-Boot-Users] uboot basics ?
Hi, I am going through the uboot drivers code for smc91111 ethernet controller in uboot.
My Objective is to know how boot loader configures the ethernet controller.
This is for the first time i am going thru a boot loader code.
I have some doubts:
How does a boot loader know which device is connected. say i have connected the smc 91111 ethernet controller - how does it know it is smc91111 controller.
I think as soon as it detects the smc91111 controller is connected. it must configure that - i think the code in drivers/smc91111.c must be executed.
What will happen if there are 2 ethernet controllers in the board. how u-boot responds to this.
However, i am not following the code given in smc91111.c i really dont know what it is doing ?.
i have the data sheets with me and going thru it. i must admit i am totally confused.
Does anybody know what constitues configuring a ethernet controller and what the code does ?.
i would request you to kindly let me the flow in u-boot. from startup to configuring ind. devices.
Any description is available in this matter will be very useful.
Any pointers in this matter is highly appreciated.
Thanks,
Regards, Ram
In message 8bf24776050830223673cd6b8e@mail.gmail.com you wrote:
How does a boot loader know which device is connected. say i have connected>
U-Boot is stupid. It doesn't "know" anything. It just does what you tell it.
the smc 91111 ethernet controller - how does it know it is smc91111 controller.
It doesn't know. It juist runs the code you configure into it.
I think as soon as it detects the smc91111 controller is connected. it must>
It doesn;t detect it. It just runs the init code if you configure it.
What will happen if there are 2 ethernet controllers in the board. how u-boot responds to this.
If just does what you configure...
Does anybody know what constitues configuring a ethernet controller and wha> t the code does ?.
I'd say such a question is off topic here. You are supposed to have a deep understanding of the hardware and driver code when digging into boot loader code.
i would request you to kindly let me the flow in u-boot. from startup to configuring ind. devices.
Just start at the reset entry point and follow the code. Ther eis no easy way to understand it all.
Any description is available in this matter will be very useful.
Read the README and the manual.
Best regards,
Wolfgang Denk
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Ram -
Wolfgang Denk