RE: [PATCH][MIPS][5/6]: AR7: serial hack

RE: [PATCH][MIPS][5/6]: AR7: serial hack

[Nico Coesel]

Hello all,
I didn't follow the entire discussion, but I might have similar problems
on the AU1100 SoC. The AU1100 also has 16550 style serial ports. The
serial console doesn't work even though I specify console=/dev/ttyS0 on
the kernel command line. Once a getty is started, the serial port is
active and working fine.

Nico

> -----Oorspronkelijk bericht-----
> Van: linux-mips-bounce@linux-mips.org 
> [mailto:linux-mips-bounce@linux-mips.org] Namens Alan Cox
> Verzonden: dinsdag 18 maart 2008 15:02
> Aan: Thomas Bogendoerfer
> CC: Matteo Croce; linux-mips@linux-mips.org; Florian 
> Fainelli; Felix Fietkau; Nicolas Thill; 
> linux-serial@vger.kernel.org; Andrew Morton
> Onderwerp: Re: [PATCH][MIPS][5/6]: AR7: serial hack
> 
> > Is there a good reason, why we don't check for BOTH_EMPTY in
> > serial8250_console_putchar() ? To match the 2.6.10 behaviour we
> 
> A very good one - we have at least 1 byte of FIFO and the 
> serial-ethernet magic console devices also use that fifo 
> emptying entirely to deduce when to send a new packet.
> 
> > would need that and this would fix the AR7 case without any special 
> > handling.
> 
> If the AR7 is an 8250 why does it need special handling? and 
> indeed why does serial work on it except for console - or 
> does that fail too.
> 
> 

RE: [PATCH][MIPS][5/6]: AR7: serial hack

[Nico Coesel]

Hello all,
I didn't follow the entire discussion, but I might have similar problems
on the AU1100 SoC. The AU1100 also has 16550 style serial ports. The
serial console doesn't work even though I specify console=/dev/ttyS0 on
the kernel command line. Once a getty is started, the serial port is
active and working fine.

Nico

> -----Oorspronkelijk bericht-----
> Van: linux-mips-bounce@linux-mips.org 
> [mailto:linux-mips-bounce@linux-mips.org] Namens Alan Cox
> Verzonden: dinsdag 18 maart 2008 15:02
> Aan: Thomas Bogendoerfer
> CC: Matteo Croce; linux-mips@linux-mips.org; Florian 
> Fainelli; Felix Fietkau; Nicolas Thill; 
> linux-serial@vger.kernel.org; Andrew Morton
> Onderwerp: Re: [PATCH][MIPS][5/6]: AR7: serial hack
> 
> > Is there a good reason, why we don't check for BOTH_EMPTY in
> > serial8250_console_putchar() ? To match the 2.6.10 behaviour we
> 
> A very good one - we have at least 1 byte of FIFO and the 
> serial-ethernet magic console devices also use that fifo 
> emptying entirely to deduce when to send a new packet.
> 
> > would need that and this would fix the AR7 case without any special 
> > handling.
> 
> If the AR7 is an 8250 why does it need special handling? and 
> indeed why does serial work on it except for console - or 
> does that fail too.
> 
> 

Serial console on Au1100

[Sergei Shtylyov]

Hello.

Nico Coesel wrote:

> Hello all,
> I didn't follow the entire discussion, but I might have similar problems
> on the AU1100 SoC. The AU1100 also has 16550 style serial ports. The
> serial console doesn't work even though I specify console=/dev/ttyS0 on
> the kernel command line. Once a getty is started, the serial port is
> active and working fine.

    This is not at all related to the discussed issue, so I've changed the 
subject. The console works like charm (seemingly for everybody, which kernel 
version are you using?

> Nico

WBR, Sergei

RE: Serial console on Au1100

[Nico Coesel]

Sergei,
I'm using kernel 2.6.24 now (before I used 2.6.21-rc4). I do see the
console messages on the framebuffer device.

Kernel options:
console=ttyS0 root=/dev/mtdblock0 rootfstype=jffs2 rw
video=au1100fb:panel:KERN_AU1100 tsdev.xres=320 tsdev.yres=234
console=tty0

If I omit console=tty0, then there is no output on the framebuffer
device or the serial port. I also tried setting the I/O address and so
on, but no luck.

Nico Coesel
 

> -----Oorspronkelijk bericht-----
> Van: Sergei Shtylyov [mailto:sshtylyov@ru.mvista.com] 
> Verzonden: dinsdag 18 maart 2008 17:44
> Aan: Nico Coesel
> CC: linux-mips@linux-mips.org
> Onderwerp: Serial console on Au1100 
> 
> Hello.
> 
> Nico Coesel wrote:
> 
> > Hello all,
> > I didn't follow the entire discussion, but I might have similar 
> > problems on the AU1100 SoC. The AU1100 also has 16550 style serial 
> > ports. The serial console doesn't work even though I specify 
> > console=/dev/ttyS0 on the kernel command line. Once a getty is 
> > started, the serial port is active and working fine.
> 
>     This is not at all related to the discussed issue, so 
> I've changed the subject. The console works like charm 
> (seemingly for everybody, which kernel version are you using?
> 
> > Nico
> 
> WBR, Sergei
> 

RE: Serial console on Au1100

[Nico Coesel]

Sergei,
I'm using kernel 2.6.24 now (before I used 2.6.21-rc4). I do see the
console messages on the framebuffer device.

Kernel options:
console=ttyS0 root=/dev/mtdblock0 rootfstype=jffs2 rw
video=au1100fb:panel:KERN_AU1100 tsdev.xres=320 tsdev.yres=234
console=tty0

If I omit console=tty0, then there is no output on the framebuffer
device or the serial port. I also tried setting the I/O address and so
on, but no luck.

Nico Coesel
 

> -----Oorspronkelijk bericht-----
> Van: Sergei Shtylyov [mailto:sshtylyov@ru.mvista.com] 
> Verzonden: dinsdag 18 maart 2008 17:44
> Aan: Nico Coesel
> CC: linux-mips@linux-mips.org
> Onderwerp: Serial console on Au1100 
> 
> Hello.
> 
> Nico Coesel wrote:
> 
> > Hello all,
> > I didn't follow the entire discussion, but I might have similar 
> > problems on the AU1100 SoC. The AU1100 also has 16550 style serial 
> > ports. The serial console doesn't work even though I specify 
> > console=/dev/ttyS0 on the kernel command line. Once a getty is 
> > started, the serial port is active and working fine.
> 
>     This is not at all related to the discussed issue, so 
> I've changed the subject. The console works like charm 
> (seemingly for everybody, which kernel version are you using?
> 
> > Nico
> 
> WBR, Sergei
> 

Re: Serial console on Au1100

[Manuel Lauss]

On Wed, Mar 19, 2008 at 10:34:40AM +0100, Nico Coesel wrote:
> Sergei,
> I'm using kernel 2.6.24 now (before I used 2.6.21-rc4). I do see the
> console messages on the framebuffer device.
> 
> Kernel options:
> console=ttyS0 root=/dev/mtdblock0 rootfstype=jffs2 rw

try adding a baudrate to the commandline, like so:
 console=ttyS0,115200

-- 
 Manuel Lauss

Re: Serial console on Au1100

[Sergei Shtylyov]

Hello.

Nico Coesel wrote:

> Sergei,
> I'm using kernel 2.6.24 now (before I used 2.6.21-rc4). I do see the
> console messages on the framebuffer device.

> Kernel options:
> console=ttyS0 root=/dev/mtdblock0 rootfstype=jffs2 rw
> video=au1100fb:panel:KERN_AU1100 tsdev.xres=320 tsdev.yres=234
> console=tty0

> If I omit console=tty0, then there is no output on the framebuffer

    You're specifying console twice, but without a baud rate. Also, do you 
have  CONFIG_SERIAL_8250_CONSOLE enabled?

> device or the serial port. I also tried setting the I/O address and so
> on, but no luck.

> Nico Coesel

WBR, Sergei