Under qemu there is a race between the TDxE read-and-clear and the SCxTDR
write. While on hardware it can be gauranteed that the read-and-clear
will happen prior to the character being written out, no such assumption
can be made under emulation. As this path happens with IRQs off and the
hardware itself doesn't care about the ordering, move the SCxTDR write
until after the read-and-clear.
Signed-off-by: Vladimir Prus <vladimir@codesourcery.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Reset the transmitter and receiver when setting up early printk.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Drain by waiting for all characters to be sent, and make sure to
wait a little bit after setting up the baud rate.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Use sci_out() instead of ctrl_outw() for early printk setup code.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
setup_early_printk() can be static, and with that, we can kill off
the early initialization variable and move the CON_BOOT check in
to the function body.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds support for the SH7720 (SH3-DSP) CPU.
Signed-off by: Markus Brunner <super.firetwister@gmail.com>
Signed-off by: Mark Jonas <toertel@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
It seems we have gained an extraneous trailing ';' on one of the
wait loops in scif_sercon_putc(). Although this is completely
benign as the apparent payload is also the empty statement, it
invites error in the future. Clean it up now.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The console subsystem already has an idea of a boot console, using the
CON_BOOT flag. The implementation has some flaws though. The major
problem is that presence of a boot console makes register_console() ignore
any other console devices (unless explicitly specified on the kernel
command line).
This patch fixes the console selection code to *not* consider a boot
console a full-featured one, so the first non-boot console registering will
become the default console instead. This way the unregister call for the
boot console in the register_console() function actually triggers and the
handover from the boot console to the real console device works smoothly.
Added a printk for the handover, so you know which console device the
output goes to when the boot console stops printing messages.
The disable_early_printk() call is obsolete with that patch, explicitly
disabling the early console isn't needed any more as it works automagically
with that patch.
I've walked through the tree, dropped all disable_early_printk() instances
found below arch/ and tagged the consoles with CON_BOOT if needed. The
code is tested on x86, sh (thanks to Paul) and mips (thanks to Ralf).
Changes to last version: Rediffed against -rc3, adapted to mips cleanups by
Ralf, fixed "udbg-immortal" cmd line arg on powerpc.
Signed-off-by: Gerd Hoffmann <kraxel@exsuse.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This allows the baud rate for earlyprintk for sh4 without the
standard BIOS to be set via the command line. This uses the same
format as i386 and x86_64, which is:
earlyprintk=serial,ttySC1,38400
The second parameter (ttySC1 above) is usually the console device
name or the io address of the serial port. I allow that to be
specified but ignore it in order to keep the format the same as
i386/x86_64.
Signed-off-by: Jamie Lenehan <lenehan@twibble.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This makes the early printk support somewhat more flexible,
moving the port definition to a config option, and making the
port initialization configurable for sh-ipl+g users.
At the same time, this allows us to trivially wire up the
SH7780 SCIF0, so that's thrown in too more or less for free.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Allow multiple early printk consoles via earlyprintk=.
With this change earlyprintk is no longer enabled by default,
it must be specified on the kernel command line. Optionally
with ,keep to prevent unreg by tty_io.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Paul Mundt