ibm4xx_quiesce_eth?
What exactly does this function do?
/* Quiesce the MAL and EMAC(s) since PIBS/OpenBIOS don't
* do this for us
*/
On the taco, with the 440EP, it doesn't seem to make any difference if I call this or not. Since I am using u-boot, is it not needed?
Cheers,
Sean
Quoted 8 lines · On Thu, 10 Jan 2008 13:38:12 -0500 Sean MacLennan <[email protected]>…
What exactly does this function do?
/* Quiesce the MAL and EMAC(s) since PIBS/OpenBIOS don't * do this for us */On the taco, with the 440EP, it doesn't seem to make any difference if I call this or not. Since I am using u-boot, is it not needed?
There are firmwares that do not reset the EMAC and MAL before passing control to the client program (Linux in our case). This can cause weird things to happen, like spurious interrupts or DMAs from the hardware overwriting kernel memory. So we quiesce the hardware really early on those.
I don't believe U-Boot has that problem. If it does, it should be fixed :)
josh
Quoted 12 lines · Josh Boyer
On Thu, 10 Jan 2008 13:38:12 -0500
Quoted 8 lines · Sean MacLennan
What exactly does this function do?
/* Quiesce the MAL and EMAC(s) since PIBS/OpenBIOS don't * do this for us */On the taco, with the 440EP, it doesn't seem to make any difference if I call this or not. Since I am using u-boot, is it not needed?
Quoted 8 lines
There are firmwares that do not reset the EMAC and MAL before passing control to the client program (Linux in our case). This can cause weird things to happen, like spurious interrupts or DMAs from the hardware overwriting kernel memory. So we quiesce the hardware really early on those.
I don't believe U-Boot has that problem. If it does, it should be fixed :)
No, U-Boot doesn't have this problem.
Best regards,
Stefan
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Quoted 6 lines · Stefan Roese
Quoted 6 lines
There are firmwares that do not reset the EMAC and MAL before passing control to the client program (Linux in our case). This can cause weird things to happen, like spurious interrupts or DMAs from the hardware overwriting kernel memory. So we quiesce the hardware really early on those.
Quoted 9 lines
Quoted 3 lines
I don't believe U-Boot has that problem. If it does, it should be fixed :)
No, U-Boot doesn't have this problem.
Best regards,
Stefan
Thanks for the confirmation! One less thing to worry about.
Cheers,
Sean