On Fri, 28 Oct 2016, Mac User wrote: > > > Penguin options: > > > root=/dev/sda3 console=ttyS0 nologo > > > Serial: blank (I tried setting serial ports to 9600 baud, > > > 1 stop bit, no parity -- didn't work. I learned through > > > trial and error that the kernel communicates at 38400 > > > baud regardless of serial settings). > > > > As soon as the ttyS0 console starts, the pmac_zilog driver will switch > > speed to whatever you asked for on the kernel command line. E.g. > > "console=ttyS0,9600n8" > > > > If you use "earlyprintk", the Mac early serial console uses 38400 > > baud. (This also applies to the output of the initial "ABCFGHIJK" > > message.) This speed isn't configurable. It uses 38400 only because > > the pmac_zilog (ttyS0) serial driver defaults to 38400 baud when it > > starts up later on. > > > > The framebuffer console (tty0) uses macfb, which is worse than 9600 > > baud, so I tend to leave that disabled and use the ttyS0 default. > > > > Since you are using a serial console, it is wise to preconfigure the > > serial ports in Penguin. The benefit of doing this depends on the Mac > > model but it never hurts and could potentially avoid an unhandled > > interrupt. > > > > ok, I only had "console-ttyS0" on the command line; I'll try > "console=ttyS0,38400n8" and "earlyprintk", as well as configuring > the serial ports in Penguin.
"console=ttyS0,38400n8" is equivalent to "console=ttyS0" for this particular serial driver (pmac_zilog). So I wouldn't change that part of your kernel command line. I'd just add "earlyprintk" to try to get some kernel messages leading up to the crash. If you then pre-configure the serial port in Penguin, the crash may go away entirely, which might be an interesting result too. -- > > -Stan > >
