On Monday 13 October 2008 03:01:35 Peter Stuge wrote: > Hi Roman, > > Roman Yeryomin wrote: > > >>> on system with native bios (tinybios): > > >>> cat /proc/tty/driver/serial > > >>> serinfo:1.0 driver revision: > > >>> 0: uart:16550A port:000003F8 irq:4 tx:945 rx:15 RTS|CTS|DTR|DSR|CD > > >>> 1: uart:16550A port:000002F8 irq:3 tx:0 rx:0 CTS|DSR|CD > > >>> > > >>> but on system with coreboot: > > >>> cat /proc/tty/driver/serial > > >>> serinfo:1.0 driver revision: > > >>> 0: uart:NS16550A port:000003F8 irq:4 tx:0 rx:0 RTS|DTR > > >>> 1: uart:unknown port:000002F8 irq:3 > > Did I overlook this message on the the list? If it wasn't sent to the > list, please keep in mind that it's nicer both for you and for others > after you to keep discussion on the list, for you because you may get > quicker replies and for others because the solutions are archived.
I understand... didn't look at the TO: address when sending email > What I find most interesting about the output above is how uart 1 is > identified differently when starting with coreboot. It would be good > to find out why. yes, that's the main question I think > > >> OK, this is kind of the problem I remember. If you have time go into > > >> the kernel, IIRC, there is a test for some modem signal and the device > > >> is not available otherwise. I am sorry to be so fuzzy but this was > > >> seven years ago. It was a weird problem. > > > > > > you think this is kernel problem? > > I don't think serial control signals is the source of your problems. > Even if they are, the problem is not in the kernel but in the > application. Unless your kernel has a bad bug in the UART layer it > will not withhold data based on control signals. > > It is much more likely that the hardware is not configured correctly. agree > > >> It seems whatever you have on that port is not asserting DTR, > > >> which is also odd. > > Please comment on this. What do you have connected to the serial > port? I'm trying to get serial console on it -- I connect to alix from my desktop with null modem cable > Does DTR on the Geode go high when your terminal software is > running? m? > > > I've asked Pascal Dornier (pcengines) how he sets up uart in his > > > bios but didn't receive an answer yet. > > Please don't ever bother Pascal Dornier with coreboot issues. That is > what this mailing list and the #coreboot IRC channel is meant for. I just asked how he sets up uart in his tinyBIOS, that's it. I think this is normal question to hw manufacturer. > > > I still think the problem is in coreboot (or libpayload)... > > > > Pascal answered me: > > > > After init -> changes to Linux driver, or does it still use Int 10 > > + Int 16 ? > > My BIOS does a redirect of these BIOS interrupts to the serial > > console. > > You can safely assume that no Linux kernel driver requires real mode > interrupts. This is an almost universal truth. > > In particular: no, the Linux serial driver does not use BIOS > interrupt services. maybe coreboot could try to use similar behavior? just to see what it gives? Roman -- coreboot mailing list: [email protected] http://www.coreboot.org/mailman/listinfo/coreboot
