This patch tries to change hvc_console to not use request_irq/free_irq if
the backend does not use irqs. This allows virtio_console to use hvc_console
without having a linker reference to request_irq/free_irq.

In addition, together with patch 2/3 it improves the performance for virtio
console input. (an earlier version of this patch was tested by Yajin on lguest)

The irq specific code is moved to hvc_irq.c and selected by the drivers that
use irqs (System p, System i, XEN).

I replaced "int irq" with the opaque "int data". The request_irq and
free_irq calls are replaced with notifier_add and notifier_del. I have also
changed the code a bit to call the notifier_add and notifier_del inside the
spinlock area as the callbacks are found via hp->ops.

Changes since last version:
o remove ifdef
o reintroduce "irq_requested" as "notified"
o cleanups, sparse..

I did not move the timer based polling into a separate polling scheme. I
played with several variants, but it seems we need to sleep/schedule in
a thread even for irq based consoles, as there are throttleing and buffer
size constraints.

I also kept hvc_struct defined in hvc_console.h so that hvc_irq.c can access
the irq_requested element.

Feedback is appreciated. virtio_console is currently the only available console
for kvm on s390. I plan to push this change as soon as all affected parties
agree on it. I would love to get test results from System p, Xen etc.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

for consistency with other Open Firmware interfaces (and Sparc).

This is just a straight replacement.

This leaves the compatibility define in place.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This does drivers/machintosh and the hvc code.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This reverts commit d05c7a80,
which included changes which should go via other subsystem
maintainers.

Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Make sure only one of them actually registers as a driver.

Also, remove cast from get_property().
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Now that get_property() returns a void *, there's no need to cast its
return value. Also, treat the return value as const, so we can
constify get_property later.

pseries platform changes.

Built for pseries_defconfig
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

So the iSeries console will be faster since it can send up to 200 bytes at
a time to the Hypervisor.  This only affects the tty part of the console,
the console writes are still in 16 byte lots.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

These are some updates from both Ryan and Arnd for the hvc_console
driver:

The main point is to enable the inclusion of a console driver
for rtas, which is currrently needed for the cell platform.

Also shuffle around some data-type declarations and moves some
functions out of include/asm-ppc64/hvconsole.h and into a new
drivers/char/hvc_console.h file.
Signed-off-by: N"Ryan S. Arnold" <rsa@us.ibm.com>
Signed-off-by: NArnd Bergmann <abergman@de.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Just set the name field directly in the device_driver structure
contained in the vio_driver struct.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Make MODULE_DEVICE_TABLE work for vio devices.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Separate the NUL character filtering from get_hvc_chars.
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When registering the hvc console port, register a list of ops (read and write)
to go with it, instead of calling fixed function names.

This allows different ports to encode the data differently.
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Remove all the vio device driver code from hvc_console.c

This will allow us to separate hvsi, hvc, and allow hvc_console to be used
without the ppc64 vio layer.
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>