> On Wed, Jun 24, 2009 at 14:56:32, Young, Joseph wrote:
> > > On Mon, Jun 22, 2009 at 13:16:55, Young, Joseph wrote:
> > > > >> I am porting the Davinci Linux kernel to a new and similar TI 
> > > > >> device, called Jacinto2. I am at the point where the init 
> > > > >> program passed to the kernel by the bootloader is initialized.
> > > > >> The problem that I am experiencing is that, whichever init 
> > > > >> program I pass, it can display text, but it cannot receive 
> > > > >> characters from the keyboard.
> > > > >> 
> > > > >> I know the serial interface is ok, because I inserted 
> > > > >> prinktk's and it both issues a serial interrupt when I press 
> > > > >> any key, as well as retrieves the correct character from the UART 
> > > > >> buffer.
> > > > >> However, the characters I type do not show up in the shell, and it 
> > > > >> doesn't seem to react to keyboard signals.
> > > > >> 
> > > > >> When one passes /bin/sh as the init program, it will display the '# 
> > > > >> /'
> > > > >> of the shell prompt, but the keyboard has no effect. When I 
> > > > >> wrote a simple 'hello world' program to print text, receive 
> > > > >> text from the user, and then print another line, it will print but 
> > > > >> not receive the keystrokes.
> > > > >> 
> > > > >> Passing /bin/ls (which redirects to busybox) will display my 
> > > > >> file system as I expect, so I don't think that my busybox is broken.
> > > > >> 
> > > > >> Is anyone familiar with how this is initialized when the kernel is 
> > > > >> booting?
> > > > >> Does anyone have a clue what I could be missing so that the 
> > > > >> serial interface would record keystrokes but not pass it to the tty 
> > > > >> interface or shell?
> > > > >
> > > > > Not sure about the details of Jacinto2, but on the other SoCs 
> > > > > in the family, the UART TX and RX signals are > commonly mux'd with 
> > > > > other pins.
> > > >
> > > > This is correct, the UART0 TX,RX, RTS, and CTS are muxed with some GPIO 
> > > > pins.
> > > >
> > > > > Have you confirmed that all the UART signals are mux'd correctly?
> > > >
> > > > Yes, because the characters I type are appearing in the serial 
> > > > buffer on the device (I am printing out the characters received 
> > > > with printk's) but they are not having an impact on the console.
> > > >
> > >
> > > I would like to guess there is something wrong with your kernel 
> > > configuration. Can you start from davinci_all_defconfig and then 
> > > modify only the parts absolutely required (like enabling
> > > ARCH_DAVINCI_JACINTO2 (??)).
> > 
> > Hmm. I tried this, using only the ARCH_JACINTO2 options, and it 
> > performed the same way. I think it's a problem with the tty layer 
> > passing the data to the shell. I don't think it's the serial layer 
> > because when I press a key, the serial interrupt kicks in, and if I 
> > add a printk to the uart_insert_char function in 
> > /include/linux/serial_core.h, I can print out the serial buffer, and it has 
> > the characters I type. I think somewhere the tty_driver or tty_buffer isn't 
> > getting initialized properly.
> > 
> > How does the tty layer pass characters to user-space processes?
> > 
> > > Also, within TI we are using filesystem from Arago project for testing 
> > > http://arago-project.org/files/releases/.
> > 
> > Thanks! As soon as I can boot my RAMDISK fs, I'll start testing with 
> > Arago :)
> 
> I meant to ask you to use the pre-built ramdisk image available from Arago to 
> eliminate any issues with the filesystem you > may be using.
> 

Well, I tried the Arago FS, and it still doesn't receive keyboard input. 
However, it provided me with additional input:
----------------------------
RAMDISK: gzip image found at block 0
EXT2-fs warning: mounting unchecked fs, running e2fsck is recommended
VFS: Mounted root (ext2 filesystem) on device 1:0.
Freeing init memory: 148K
uart_open(0) called
ttyS0 - using backup timer
*** run_init_process(/bin/sh)
/bin/sh: can't access tty; job control turned off / #
---------------------------

It says it can't access the tty. Is this normal when booting with a serial 
console through ttyS0?

Thanks for your time,
Joe_______________________________________________
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