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
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Quoted 2 lines · In message <[email protected]> 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.
Quoted 2 lines
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.
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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.
Quoted 2 lines
What will happen if there are 2 ethernet controllers in the board. how u-boot responds to this.
If just does what you configure...
Quoted 2 lines
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.
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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.
Quoted 1 line
Any description is available in this matter will be very useful.
Read the README and the manual.
Best regards,
Wolfgang Denk
Signature · 3 lines
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