I found that my 68040/68360 test programs would not run even after
I fixed the `wrong BSP' problem.
It seems that there's a bug in the interrupt handling code for
processors with hardware interrupt stacks (e.g. 68040). The wrong
status register was getting pushed on the stack for the `return
from exception' to call _ISR__Dispatch. This ended up making
the context switch code run on the interrupt stack, so interrupt-driven
context switches would always fail.
I guess that no one has tried running any of the RTEMS-4.0 snapshots
on a 68040 machine!
Anyhow, here are the patches for
1) gen68360.cfg --- to fix the `wrong-BSP' problem.
2) m68k/cpu_asm.s --- to fix the hardware interrupt stack problem.
With these patches in place, the network demo programs run on my
68040/68360 system. The paranoia program runs with no failures,
defects nor flaws.
Remember the test to see if a socket could be read and written at
the same time by two different tasks? I discovered that if both
tasks attempt to close the socket a panic can occur from inside the
BSD code.
Closing the same socket twice from two different threads is
certainly an error, but a panic is not the greatest error reporting
method :-)
The following small change to the socket close routine should reduce
the chances of the panic.
1. Finally fixes raw interrupts for pc386
2. Makes some minor cleanup in console and startup
3. Makes rtems_termios_dequeue_characters() to return count of
outstanding chars - it allows to simplify console isrs a little
bit.
4. pc386 uart modified to be friendlier to termios parameter changes,
to have minor performance improvement and to take advantage of
of above termios modification.
Here's a patch to make the rtems_showroute routine a little more
useful. For `host' route table entries the link-level address is now
displayed. This is equivalent to the old `show arp table'
information displayed by the KA9Q code.
I fixed the problems noted by Victor Vengerov.
1) Fix typo in cfsetispeed().
2) In rtems_termios_open, ensure that args->iop->data1 is set before calling
device-specific open routine.
I've fixed a few minor probs with the optimised version that Eric put
together for me the other day and sent the fixes back to him. Provided he
doesn't have a problem with it we've got a pretty solid in_cksum for the
ColdFire as well as straight m68k. I've enclosed my updated in_cksum_m68k.c
At the moment my own bottlenecks are elsewhere...as my driver is pulling
16bit data chunks through a libchip-esq access routine from the chip which
for a polled I/O device is never going to be quick.
Eric> NB : there is still a bug on PC386 serial line : exit does not
Eric> flush the remaining output queue. As this is not a bug in the
Eric> driver itself but somewhere in PC386 initialization/termios
Eric> relationship it will be part of another patch.
Eric> NB2 : As Emmanuel excerced the exception hanlder code, while
Eric> porting the SMC driver to the new BSD stack, we found a bug
Eric> in the exception handler : it shall not delete the current
Eric> thread in case we are running at interrupt level. This will
Eric> be part of another patch...
So here is the patch. This patch fixes the two problems mentionned above
+ it use vpath mechanism intead of copying the irq related files in
the right directory. This avoid to compile them each time and is
more homogenous with other Makefiles.
I think I figured out why rtems_panic was locking up instead of
shutting down the executive and returning to the code that called
boot_card().
Later on there is code to print some messages on the standard error
stream, a recursive call back to rtems_verror (through rtems_error)
and finally a call to _exit().
I think that the _Thread_Disable_dispatch() is preventing the final
context switch back to the boot_card() code. Does this sound right
to you?
Here is a patch that enables to catch exception
and get message before crashing RTEMS :)
It should be generic to any Intel port although enabled
only for pc386 BSP...
[Joel] I fixed the bug I introduced in irq_asm.s...
"Thomas Doerfler" <td@imd.m.isar.de> wrote:
>
> While implementing/testing the console/termios support for
> PPC403 in RTEMS-4.0.0-beta3, I am stuck at a certain location in
> termios.c:
>
> During "rtems_termios_initialize", the main control data structure
> "*tty" is allocated using malloc(). (Note, that malloc does not
> clear the allocated memory and my BSP does not clear memory during
> startup). Furtheron, a lot of fields of that structure are
> initialized, but the field "rawOutBufState" is not, and therefore
> keeps an arbitrary contents.
>
> When "osend()" is called the first time(with the serial device
> driver working in interrupt mode), termios gets stuck and will not
> call the device drivers output function.
>
> My questions now are:
>
> - anybody already experienced this bug?
> - is it a bug at all or did I do anything fundamentally wrong?
> - is there already a common bugfix for that?
>
> I don't like poking around in other people code, as long as I am
> not absolutely sure, what I do...
Yes, there's a bug there.
I thought that Joel had patched this already, but here's a patch to
fix this. This patch also addresses a concern that many others have
raised regarding enabling and disabling of transmitter interrupts.
First, here's the example I've been using of a simple UART-style
interrupt-driven driver:
===============================================================
void
device_write_routine (int minor, char *buf, int count)
{
UART->control_register &= ~UART_TRANSMITTER_READY;
UART->output_register = *buf;
UART->control_register |= UART_TRANSMIT_INTERRUPT_ENABLE;
}
void
device_transmit_interrupt_routine (int vector)
{
UART->control_register &= ~UART_TRANSMIT_INTERRUPT_ENABLE;
rtems_termios_dequeue_characters (device_ttyp, 1);
}
==============================================================
Several people have expressed their concern about the disable/enable
of transmitter interrupts for every character. On some machines
this disable/enable is an expensive operation. With the attached
patch applied you can write the two routines as:
==============================================================
void
device_write_routine (int minor, char *buf, int count)
{
code_to_clear_transmitter_ready_status ();
if (device_ttyp->rawOutBufState == rob_idle)
code_to_enable_transmitter_interrupts ();
code_to_send_one_character_to_transmitter (*buf);
}
void
device_transmit_interrupt_routine (int vector)
{
rtems_termios_dequeue_characters (device_ttyp, 1);
if (device_ttyp->rawOutBufState == rob_idle)
code_to_disable_transmitter_interrupts ();
}
===============================================================
- Use the "hlt" instruction for the Idle thread,
- Optimise interrupt PATH leadding to thread wakeup,
- Preparation for Intel exception management that should
come before the end of the week...
make solaris target buildable.
> 1. The ipc check fails since solaris does not define union semun.
> The unix port code actually defines this type itself on solaris. Doing
> the same thing lets it get configured. Then...
> 2. It looks like BSDINSTALL is not defined properly.
BSDINSTALL is defined in make/host.cfg.in as
BSDINSTALL=@INSTALL@
@INSTALL@ is generated by autoconf's standard macro AC_PROG_INSTALL, which
is widely used in almost any autoconf/automake configured package. In case
there is really something wrong with it, then it must be considered a bug
in autoconf.
I can see a doubious fragment in AC_PROG_INSTALL, which is used when no
appropriate bsd-install is found.
Finally Ralf saw a problem with the find on solaris which I also saw and
fixed.
