powerpc: udbg-based backend for hvc_console

This adds a new backend for the hvc console based on the low-level
udbg callbacks.  This effectively implements a working runtime console
in terms of the simple udbg primitives.  This is kind of a hack -
since udbg isn't something you really want to be using routinely - but
it's really useful during bringup.

This can be used to quickly implement a userspace-usable console while
you're working on a proper driver for whatever console I/O device the
hardware has.  Or, it can be used to avoid writing a full blown
tty/console driver entirely for quick-and-dirty I/O hardware that will
later be replaced by something else.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/char/Makefile b/drivers/char/Makefile
index 438f71317c5c..52e15524af39 100644
--- a/drivers/char/Makefile
+++ b/drivers/char/Makefile
@@ -50,6 +50,7 @@ obj-$(CONFIG_HVC_BEAT)		+= hvc_beat.o
 obj-$(CONFIG_HVC_DRIVER)        += hvc_console.o
 obj-$(CONFIG_HVC_IRQ)           += hvc_irq.o
 obj-$(CONFIG_HVC_XEN)           += hvc_xen.o
+obj-$(CONFIG_HVC_UDBG)          += hvc_udbg.o
 obj-$(CONFIG_VIRTIO_CONSOLE)    += virtio_console.o
 obj-$(CONFIG_RAW_DRIVER)        += raw.o
 obj-$(CONFIG_SGI_SNSC)          += snsc.o snsc_event.o