Which Linux driver (source code) is used for tty0 (console) on MALTA?

Which Linux driver (source code) is used for tty0 (console) on MALTA?

[Ardelean, Andrei]

Hi,

I am using MALTA and my goal is to port MIPS Linux on a new platform.
Which driver (source code) is used for tty0 (console)? I see the support
for "early console" but I think that this is not the real Linux driver
used after boot stage.

More general, how to find which code source is used for an embedded
driver (part of the Kernel at compiling time) for each h/w resource.
MIPS Linux distribution comes with a lot of drivers but I have
difficulties to figure out which one is used for MALTA. Is it a files
where all those are registered?

Thanks,
Andrei
  

Which Linux driver (source code) is used for tty0 (console) on MALTA?

[Ardelean, Andrei]

Hi,

I am using MALTA and my goal is to port MIPS Linux on a new platform.
Which driver (source code) is used for tty0 (console)? I see the support
for "early console" but I think that this is not the real Linux driver
used after boot stage.

More general, how to find which code source is used for an embedded
driver (part of the Kernel at compiling time) for each h/w resource.
MIPS Linux distribution comes with a lot of drivers but I have
difficulties to figure out which one is used for MALTA. Is it a files
where all those are registered?

Thanks,
Andrei
  

RE: Which Linux driver (source code) is used for tty0 (console) on MALTA?

[Chen, Tiejun]

> -----Original Message-----
> From: linux-mips-bounce@linux-mips.org 
> [mailto:linux-mips-bounce@linux-mips.org] On Behalf Of 
> Ardelean, Andrei
> Sent: Thursday, September 23, 2010 2:49 AM
> To: linux-mips@linux-mips.org
> Subject: Which Linux driver (source code) is used for tty0 
> (console) on MALTA? 
> 
> Hi,
> 
> I am using MALTA and my goal is to port MIPS Linux on a new platform.
> Which driver (source code) is used for tty0 (console)? I see 
> the support for "early console" but I think that this is not 
> the real Linux driver used after boot stage.

$ cat arch/mips/configs/malta_defconfig | grep SERIAL
# CONFIG_SERIAL_NONSTANDARD is not set
CONFIG_SERIAL_8250=y
CONFIG_SERIAL_8250_CONSOLE=y
CONFIG_SERIAL_8250_PCI=y
CONFIG_SERIAL_8250_NR_UARTS=4
CONFIG_SERIAL_8250_RUNTIME_UARTS=4
# CONFIG_SERIAL_8250_EXTENDED is not set
CONFIG_SERIAL_CORE=y
CONFIG_SERIAL_CORE_CONSOLE=y
# CONFIG_SERIAL_JSM is not set

Cheers
Tiejun

> 
> More general, how to find which code source is used for an 
> embedded driver (part of the Kernel at compiling time) for 
> each h/w resource.
> MIPS Linux distribution comes with a lot of drivers but I 
> have difficulties to figure out which one is used for MALTA. 
> Is it a files where all those are registered?
> 
> Thanks,
> Andrei
>   
> 
> 

RE: Which Linux driver (source code) is used for tty0 (console) on MALTA?

[Chen, Tiejun]

> -----Original Message-----
> From: linux-mips-bounce@linux-mips.org 
> [mailto:linux-mips-bounce@linux-mips.org] On Behalf Of 
> Ardelean, Andrei
> Sent: Thursday, September 23, 2010 2:49 AM
> To: linux-mips@linux-mips.org
> Subject: Which Linux driver (source code) is used for tty0 
> (console) on MALTA? 
> 
> Hi,
> 
> I am using MALTA and my goal is to port MIPS Linux on a new platform.
> Which driver (source code) is used for tty0 (console)? I see 
> the support for "early console" but I think that this is not 
> the real Linux driver used after boot stage.

$ cat arch/mips/configs/malta_defconfig | grep SERIAL
# CONFIG_SERIAL_NONSTANDARD is not set
CONFIG_SERIAL_8250=y
CONFIG_SERIAL_8250_CONSOLE=y
CONFIG_SERIAL_8250_PCI=y
CONFIG_SERIAL_8250_NR_UARTS=4
CONFIG_SERIAL_8250_RUNTIME_UARTS=4
# CONFIG_SERIAL_8250_EXTENDED is not set
CONFIG_SERIAL_CORE=y
CONFIG_SERIAL_CORE_CONSOLE=y
# CONFIG_SERIAL_JSM is not set

Cheers
Tiejun

> 
> More general, how to find which code source is used for an 
> embedded driver (part of the Kernel at compiling time) for 
> each h/w resource.
> MIPS Linux distribution comes with a lot of drivers but I 
> have difficulties to figure out which one is used for MALTA. 
> Is it a files where all those are registered?
> 
> Thanks,
> Andrei
>   
> 
> 

Re: Which Linux driver (source code) is used for tty0 (console) on MALTA?

[Ralf Baechle]

On Wed, Sep 22, 2010 at 11:49:25AM -0700, Ardelean, Andrei wrote:

> I am using MALTA and my goal is to port MIPS Linux on a new platform.
> Which driver (source code) is used for tty0 (console)? I see the support
> for "early console" but I think that this is not the real Linux driver
> used after boot stage.

Correct.  Early console uses an extremly simple driver which in general
is separate from the full blown driver that takes over later.

> More general, how to find which code source is used for an embedded
> driver (part of the Kernel at compiling time) for each h/w resource.
> MIPS Linux distribution comes with a lot of drivers but I have
> difficulties to figure out which one is used for MALTA. Is it a files
> where all those are registered?

For any modern style driver that information is available through sysfs.
For example on this laptop here:

# cd /sys/devices/platform/serial8250
# ls -l
total 0
lrwxrwxrwx. 1 root root    0 Sep 24 12:20 driver -> ../../../bus/platform/drivers/serial8250
-r--r--r--. 1 root root 4096 Sep 24 12:20 modalias
drwxr-xr-x. 2 root root    0 Sep 24 12:20 power
lrwxrwxrwx. 1 root root    0 Sep 24 12:20 subsystem -> ../../../bus/platform
drwxr-xr-x. 5 root root    0 Sep 24 12:20 tty
-rw-r--r--. 1 root root 4096 Sep 24 12:20 uevent
#

So you see the driver being used is the 8250 driver.  Similar you can
find the driver for a PCI device in /sys/devices/pci* etc.

  Ralf