Odd-looking serial console prompt on RPI2

[Shawn Webb]

On Sat, Mar 11, 2017 at 12:17:58PM -0700, Ian Lepore wrote:
> On Sat, 2017-03-11 at 13:09 -0500, Shawn Webb wrote:
> > On Sat, Mar 11, 2017 at 11:04:04AM -0700, Ian Lepore wrote:
> > > 
> > > On Sat, 2017-03-11 at 12:49 -0500, Shawn Webb wrote:
> > > > 
> > > > On Tue, Mar 07, 2017 at 02:29:18PM -0500, Shawn Webb wrote:
> > > > > 
> > > > > 
> > > > > On Tue, Mar 07, 2017 at 02:09:37PM -0500, Shawn Webb wrote:
> > > > > > 
> > > > > > 
> > > > > > On Sat, Mar 04, 2017 at 03:02:45PM -0700, Ian Lepore wrote:
> > > > > > > 
> > > > > > > 
> > > > > > > The bugs should be fixed as of r314682. ?It looks like the
> > > > > > > bugs
> > > > > > > have
> > > > > > > long been in the pl011 driver, but were masked by having a
> > > > > > > fifo
> > > > > > > depth
> > > > > > > of 1 byte -- it all sorta worked by accident previously.
> > > > > > Thanks for the fix! But it looks to be only partial. When I
> > > > > > connect to
> > > > > > the serial console via either cu or screen, I don't get
> > > > > > corrupted
> > > > > > text,
> > > > > > but no keypresses are registered. Hitting enter at the login
> > > > > > prompt does
> > > > > > absolutely nothing. I'm at the latest commit of
> > > > > > hardened/current/master
> > > > > > on HardenedBSD for both the RPI3 and my laptop.
> > > > > > 
> > > > > > I'm using this serial cable from Adafruit:
> > > > > > https://www.adafruit.com/product/954
> > > > > It looks like I had a bad cable. Sorry for the line noise.
> > > > > Switching to
> > > > > a different cable worked.
> > > > Looks like the problem is back, but manifest in a different way.
> > > > Screenshot:
> > > > 
> > > > https://goo.gl/photos/XYx6v1jCTVCGrnhd6
> > > > 
> > > > Thanks,
> > > > 
> > > I wonder if rpi3 needs the same smaller-fifo fix as a 32-bit rpi.
> > > ?Just
> > > to test that theory, can you see if the attached patch fixes
> > > problem?
> > > ?If it does, I'll figure out how to detect rpi3 at runtime and set
> > > the
> > > sizes properly.
> > > 
> > > -- Ian
> > > 
> > > Index: sys/dev/uart/uart_dev_pl011.c
> > > ===================================================================
> > > --- sys/dev/uart/uart_dev_pl011.c	(revision 314917)
> > > +++ sys/dev/uart/uart_dev_pl011.c	(working copy)
> > > @@ -464,7 +464,7 @@ uart_pl011_bus_probe(struct uart_softc *sc)
> > > ?	is_bcm2835 = ofw_bus_is_compatible(sc->sc_dev,
> > > "brcm,bcm2835-pl011") ||
> > > ?	????ofw_bus_is_compatible(sc->sc_dev, "broadcom,bcm2835-
> > > uart");
> > > ?#else
> > > -	is_bcm2835 = false;
> > > +	is_bcm2835 = true;
> > > ?#endif
> > > ?	hwrev = __uart_getreg(&sc->sc_bas, UART_PIDREG_2) >> 4;
> > > ?	if (hwrev <= 2 || is_bcm2835) {
> > Sure. I'll report back either tonight or tomorrow.
> > 
> > Thanks,
> > 
> 
> Actually, I think a proper solution will be something like the attached
> patch. ?After some spelunking on the web I think the rpi3 fifos are the
> smaller size because the fdt data contains the linux-style workaround
> (which overrides the primecell periphid value with fdt data). ?This
> patch looks for that in addition to looking for the rpi compatible
> strings (still required to handle old-style freebsd fdt data).
> 
> -- Ian

Cool. I'll give that patch a shot soon.

Thanks a lot!

-- 
Shawn Webb
Cofounder and Security Engineer
HardenedBSD

GPG Key ID:          0x6A84658F52456EEE
GPG Key Fingerprint: 2ABA B6BD EF6A F486 BE89  3D9E 6A84 658F 5245 6EEE
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-arm/attachments/20170311/301e131c/attachment.sig>