Current Cell hardware is using the console through a set
of rtas calls. This driver is needed to get console
output on those boards.
Signed-off-by: Arnd Bergmann <[email protected]>
Index: linus-2.6/drivers/char/hvc_rtas.c
===================================================================
--- /dev/null
+++ linus-2.6/drivers/char/hvc_rtas.c
@@ -0,0 +1,138 @@
+/*
+ * IBM RTAS driver interface to hvc_console.c
+ *
+ * (C) Copyright IBM Corporation 2001-2005
+ * (C) Copyright Red Hat, Inc. 2005
+ *
+ * Author(s): Maximino Augilar <IBM STI Design Center>
+ * : Ryan S. Arnold <[email protected]>
+ * : Utz Bacher <[email protected]>
+ * : David Woodhouse <[email protected]>
+ *
+ * inspired by drivers/char/hvc_console.c
+ * written by Anton Blanchard and Paul Mackerras
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+
+#include <asm/irq.h>
+#include <asm/rtas.h>
+#include "hvc_console.h"
+
+#define hvc_rtas_cookie 0x67781e15
+struct hvc_struct *hvc_rtas_dev;
+
+#define RTASCONS_PUT_ATTEMPTS 16
+
+static int rtascons_put_char_token = RTAS_UNKNOWN_SERVICE;
+static int rtascons_get_char_token = RTAS_UNKNOWN_SERVICE;
+static int rtascons_put_delay = 100;
+module_param_named(put_delay, rtascons_put_delay, int, 0644);
+
+static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf, int count)
+{
+ int done;
+
+ /* if there is more than one character to be displayed, wait a bit */
+ for (done = 0; done < count; done++) {
+ int result;
+ result = rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[done]);
+ if (result)
+ break;
+ }
+ /* the calling routine expects to receive the number of bytes sent */
+ return done;
+}
+
+static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count)
+{
+ int i;
+
+ for (i = 0; i < count; i++) {
+ int c, err;
+
+ err = rtas_call(rtascons_get_char_token, 0, 2, &c);
+ if (err)
+ break;
+
+ buf[i] = c;
+ }
+
+ return i;
+}
+
+static struct hv_ops hvc_rtas_get_put_ops = {
+ .get_chars = hvc_rtas_read_console,
+ .put_chars = hvc_rtas_write_console,
+};
+
+static int hvc_rtas_init(void)
+{
+ struct hvc_struct *hp;
+
+ if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
+ rtascons_put_char_token = rtas_token("put-term-char");
+ if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
+ return -EIO;
+
+ if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
+ rtascons_get_char_token = rtas_token("get-term-char");
+ if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
+ return -EIO;
+
+ BUG_ON(hvc_rtas_dev);
+
+ /* Allocate an hvc_struct for the console device we instantiated
+ * earlier. Save off hp so that we can return it on exit */
+ hp = hvc_alloc(hvc_rtas_cookie, NO_IRQ, &hvc_rtas_get_put_ops);
+ if (IS_ERR(hp))
+ return PTR_ERR(hp);
+ hvc_rtas_dev = hp;
+ return 0;
+}
+module_init(hvc_rtas_init);
+
+/* This will tear down the tty portion of the driver */
+static void __exit hvc_rtas_exit(void)
+{
+ /* Really the fun isn't over until the worker thread breaks down and the
+ * tty cleans up */
+ if (hvc_rtas_dev)
+ hvc_remove(hvc_rtas_dev);
+}
+module_exit(hvc_rtas_exit); /* before drivers/char/hvc_console.c */
+
+/* This will happen prior to module init. There is no tty at this time? */
+static int hvc_rtas_console_init(void)
+{
+ rtascons_put_char_token = rtas_token("put-term-char");
+ if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
+ return -EIO;
+ rtascons_get_char_token = rtas_token("get-term-char");
+ if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
+ return -EIO;
+
+ hvc_instantiate(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops );
+ add_preferred_console("hvc", 0, NULL);
+ return 0;
+}
+console_initcall(hvc_rtas_console_init);
Index: linus-2.6/drivers/char/Makefile
===================================================================
--- linus-2.6.orig/drivers/char/Makefile
+++ linus-2.6/drivers/char/Makefile
@@ -43,6 +43,7 @@ obj-$(CONFIG_SX) += sx.o generic_serial
obj-$(CONFIG_RIO) += rio/ generic_serial.o
obj-$(CONFIG_HVC_DRIVER) += hvc_console.o
obj-$(CONFIG_HVC_CONSOLE) += hvc_vio.o hvsi.o
+obj-$(CONFIG_HVC_RTAS) += hvc_rtas.o
obj-$(CONFIG_RAW_DRIVER) += raw.o
obj-$(CONFIG_SGI_SNSC) += snsc.o snsc_event.o
obj-$(CONFIG_MMTIMER) += mmtimer.o
Index: linus-2.6/drivers/char/Kconfig
===================================================================
--- linus-2.6.orig/drivers/char/Kconfig
+++ linus-2.6/drivers/char/Kconfig
@@ -578,6 +578,13 @@ config HVC_CONSOLE
console. This driver allows each pSeries partition to have a console
which is accessed via the HMC.
+config HVC_RTAS
+ bool "IBM RTAS Console support"
+ depends on PPC_RTAS
+ select HVC_DRIVER
+ help
+ IBM Console device driver which makes use of RTAS
+
config HVCS
tristate "IBM Hypervisor Virtual Console Server support"
depends on PPC_PSERIES
--
Hi,
I have a couple of nitpicks below, nothing major.
Since it's such a simple driver, it's easy to use as a base for similar
ones, and as such it'd be nice to have it as clean as possible to avoid
others to inherit strangeness.
-Olof
On Thu, Mar 23, 2006 at 12:00:02AM +0100, Arnd Bergmann wrote:
> +static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf, int count)
> +{
> + int done;
> +
> + /* if there is more than one character to be displayed, wait a bit */
> + for (done = 0; done < count; done++) {
> + int result;
> + result = rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[done]);
> + if (result)
> + break;
Why introduce a scope-local variable just to check it?
if(rtas_call(...)) would be cleaner.
> + }
> + /* the calling routine expects to receive the number of bytes sent */
> + return done;
> +}
> +
> +static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count)
> +{
> + int i;
> +
> + for (i = 0; i < count; i++) {
> + int c, err;
> +
> + err = rtas_call(rtascons_get_char_token, 0, 2, &c);
> + if (err)
> + break;
Same here
> +
> + buf[i] = c;
> + }
> +
> + return i;
> +}
> +
> +static struct hv_ops hvc_rtas_get_put_ops = {
> + .get_chars = hvc_rtas_read_console,
> + .put_chars = hvc_rtas_write_console,
> +};
> +
> +static int hvc_rtas_init(void)
> +{
> + struct hvc_struct *hp;
> +
> + if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
> + rtascons_put_char_token = rtas_token("put-term-char");
> + if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
> + return -EIO;
> +
> + if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
> + rtascons_get_char_token = rtas_token("get-term-char");
> + if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
> + return -EIO;
> +
> + BUG_ON(hvc_rtas_dev);
> +
> + /* Allocate an hvc_struct for the console device we instantiated
> + * earlier. Save off hp so that we can return it on exit */
> + hp = hvc_alloc(hvc_rtas_cookie, NO_IRQ, &hvc_rtas_get_put_ops);
> + if (IS_ERR(hp))
> + return PTR_ERR(hp);
> + hvc_rtas_dev = hp;
> + return 0;
> +}
> +module_init(hvc_rtas_init);
> +
> +/* This will tear down the tty portion of the driver */
> +static void __exit hvc_rtas_exit(void)
> +{
> + /* Really the fun isn't over until the worker thread breaks down and the
> + * tty cleans up */
> + if (hvc_rtas_dev)
> + hvc_remove(hvc_rtas_dev);
> +}
> +module_exit(hvc_rtas_exit); /* before drivers/char/hvc_console.c */
Cryptic comment?
> +/* This will happen prior to module init. There is no tty at this time? */
> +static int hvc_rtas_console_init(void)
> +{
> + rtascons_put_char_token = rtas_token("put-term-char");
> + if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
> + return -EIO;
> + rtascons_get_char_token = rtas_token("get-term-char");
> + if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
> + return -EIO;
> +
> + hvc_instantiate(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops );
> + add_preferred_console("hvc", 0, NULL);
> + return 0;
> +}
> +console_initcall(hvc_rtas_console_init);
> Index: linus-2.6/drivers/char/Makefile
> ===================================================================
> --- linus-2.6.orig/drivers/char/Makefile
> +++ linus-2.6/drivers/char/Makefile
> @@ -43,6 +43,7 @@ obj-$(CONFIG_SX) += sx.o generic_serial
> obj-$(CONFIG_RIO) += rio/ generic_serial.o
> obj-$(CONFIG_HVC_DRIVER) += hvc_console.o
> obj-$(CONFIG_HVC_CONSOLE) += hvc_vio.o hvsi.o
> +obj-$(CONFIG_HVC_RTAS) += hvc_rtas.o
> obj-$(CONFIG_RAW_DRIVER) += raw.o
> obj-$(CONFIG_SGI_SNSC) += snsc.o snsc_event.o
> obj-$(CONFIG_MMTIMER) += mmtimer.o
> Index: linus-2.6/drivers/char/Kconfig
> ===================================================================
> --- linus-2.6.orig/drivers/char/Kconfig
> +++ linus-2.6/drivers/char/Kconfig
> @@ -578,6 +578,13 @@ config HVC_CONSOLE
> console. This driver allows each pSeries partition to have a console
> which is accessed via the HMC.
>
> +config HVC_RTAS
> + bool "IBM RTAS Console support"
> + depends on PPC_RTAS
> + select HVC_DRIVER
> + help
> + IBM Console device driver which makes use of RTAS
> +
> config HVCS
> tristate "IBM Hypervisor Virtual Console Server support"
> depends on PPC_PSERIES
>
> --
>
> -
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> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
Am Thursday 23 March 2006 22:32 schrieb Olof Johansson:
> > +static inline int hvc_rtas_write_console(uint32_t vtermno, const char
> > *buf, int count) +{
> > +?????int done;
> > +
> > +?????/* if there is more than one character to be displayed, wait a bit */
> > +?????for (done = 0; done < count; done++) {
> > +?????????????int result;
> > +?????????????result = rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[done]);
> > +?????????????if (result)
> > +?????????????????????break;
>
> Why introduce a scope-local variable just to check it?
> ????????????????if(rtas_call(...)) ? would be cleaner.
I don't like doing the important stuff inside of another expression,
and I prefer conditions not to have side-effects.
If nobody else has a strong opinion on it, I'd prefer to leave it.
BTW, who is the current maintainer of hvc_console? Ryan is working on
glibc nowadays, right?
> > +?????/* Really the fun isn't over until the worker thread breaks down
> > and the +????? * tty cleans up */
> > +?????if (hvc_rtas_dev)
> > +?????????????hvc_remove(hvc_rtas_dev);
> > +}
> > +module_exit(hvc_rtas_exit); /* before drivers/char/hvc_console.c */
>
> Cryptic comment?
No idea how what it was about, I'll remove it.
Arnd <><
On Thu, Mar 23, 2006 at 11:36:19PM +0100, Arnd Bergmann wrote:
> Am Thursday 23 March 2006 22:32 schrieb Olof Johansson:
> > > +static inline int hvc_rtas_write_console(uint32_t vtermno, const char
> > > *buf, int count) +{
> > > +?????int done;
> > > +
> > > +?????/* if there is more than one character to be displayed, wait a bit */
> > > +?????for (done = 0; done < count; done++) {
> > > +?????????????int result;
> > > +?????????????result = rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[done]);
> > > +?????????????if (result)
> > > +?????????????????????break;
> >
> > Why introduce a scope-local variable just to check it?
> > ????????????????if(rtas_call(...)) ? would be cleaner.
>
> I don't like doing the important stuff inside of another expression,
> and I prefer conditions not to have side-effects.
> If nobody else has a strong opinion on it, I'd prefer to leave it.
Ok. It just looked silly to have the declaration/assignment/test and no
use of result outside of those three lines.
> BTW, who is the current maintainer of hvc_console? Ryan is working on
> glibc nowadays, right?
That's what I think IBM pays him to do, that's never stopped people from
maintaining other code in the past though. :-)
-Olof
As notice by Olof Johansson, the comment about module_exit
in hvc_rtas is rather confusing, so remove it.
Signed-off-by: Arnd Bergmann <[email protected]>
---
Index: linus-2.6/drivers/char/hvc_rtas.c
===================================================================
--- linus-2.6.orig/drivers/char/hvc_rtas.c
+++ linus-2.6/drivers/char/hvc_rtas.c
@@ -119,7 +119,7 @@ static void __exit hvc_rtas_exit(void)
if (hvc_rtas_dev)
hvc_remove(hvc_rtas_dev);
}
-module_exit(hvc_rtas_exit); /* before drivers/char/hvc_console.c */
+module_exit(hvc_rtas_exit);
/* This will happen prior to module init. There is no tty at this time? */
static int hvc_rtas_console_init(void)