[PATCH] [kgdb] Start kgdboc uart port to answer gdb break signal Ctrl+C without openning ttys.

[PATCH] [kgdb] Start kgdboc uart port to answer gdb break signal Ctrl+C without openning ttys.

[sonic zhang]

 Current kgdboc only configures the uart port in poll mode, which block
 any gdb break signal Ctrl+C from taking effect till a tty on the port is
 opened by an application. This patch introduces 2 hook functions in
 struct tty_operations and uart_operations. The kgdboc port can be start
 up without openning ttys after gdb is connected.

Signed-off-by: Sonic Zhang <sonic.adi@gmail.com>
---
 drivers/serial/kgdboc.c      |    8 +++++++-
 drivers/serial/serial_core.c |   38 ++++++++++++++++++++++++++++++++++++++
 include/linux/serial_core.h  |    9 +++++++++
 include/linux/tty_driver.h   |    5 +++++
 4 files changed, 59 insertions(+), 1 deletions(-)

diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index eadc1ab..5d91f3d 100644
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -70,6 +70,9 @@ static int configure_kgdboc(void)
 
 	configured = 1;
 
+	kgdb_tty_driver->ops->kgdboc_port_startup(kgdb_tty_driver,
+					kgdb_tty_line);
+
 	return 0;
 
 noconfig:
@@ -90,8 +93,11 @@ static int __init init_kgdboc(void)
 
 static void cleanup_kgdboc(void)
 {
-	if (configured == 1)
+	if (configured == 1) {
+		kgdb_tty_driver->ops->kgdboc_port_shutdown(kgdb_tty_driver,
+					kgdb_tty_line);
 		kgdb_unregister_io_module(&kgdboc_io_ops);
+	}
 }
 
 static int kgdboc_get_char(void)
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 73e9b8f..07f1b04 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -2244,6 +2244,39 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
 	}
 }
 
+#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
+	defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
+static int uart_kgdboc_port_startup(struct tty_driver *driver, int line)
+{
+	struct uart_driver *drv = driver->driver_state;
+	struct uart_state *state = drv->state + line;
+	struct uart_port *port;
+
+	if (!state || !state->port)
+		return -1;
+
+	port = state->port;
+	if (port->ops->kgdboc_port_startup)
+		return port->ops->kgdboc_port_startup(port);
+	else
+		return -1;
+}
+
+static void uart_kgdboc_port_shutdown(struct tty_driver *driver, int line)
+{
+	struct uart_driver *drv = driver->driver_state;
+	struct uart_state *state = drv->state + line;
+	struct uart_port *port;
+
+	if (!state || !state->port)
+		return;
+
+	port = state->port;
+	if (port->ops->kgdboc_port_shutdown)
+		port->ops->kgdboc_port_shutdown(port);
+}
+#endif
+
 #ifdef CONFIG_CONSOLE_POLL
 
 static int uart_poll_init(struct tty_driver *driver, int line, char *options)
@@ -2323,6 +2356,11 @@ static const struct tty_operations uart_ops = {
 #endif
 	.tiocmget	= uart_tiocmget,
 	.tiocmset	= uart_tiocmset,
+#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
+	defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
+	.kgdboc_port_startup	= uart_kgdboc_port_startup,
+	.kgdboc_port_shutdown	= uart_kgdboc_port_shutdown,
+#endif
 #ifdef CONFIG_CONSOLE_POLL
 	.poll_init	= uart_poll_init,
 	.poll_get_char	= uart_poll_get_char,
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 3b2f6c0..4a15311 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -214,6 +214,15 @@ struct uart_ops {
 	void		(*config_port)(struct uart_port *, int);
 	int		(*verify_port)(struct uart_port *, struct serial_struct *);
 	int		(*ioctl)(struct uart_port *, unsigned int, unsigned long);
+#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
+	defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
+	/*
+	 * Start up serial port earlier in kgdboc to support gdb break
+	 * signal Ctrl+C.
+	 */
+	int		(*kgdboc_port_startup)(struct uart_port *);
+	void		(*kgdboc_port_shutdown)(struct uart_port *);
+#endif
 #ifdef CONFIG_CONSOLE_POLL
 	void	(*poll_put_char)(struct uart_port *, unsigned char);
 	int		(*poll_get_char)(struct uart_port *);
diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h
index 16d2794..efd26cf 100644
--- a/include/linux/tty_driver.h
+++ b/include/linux/tty_driver.h
@@ -220,6 +220,11 @@ struct tty_operations {
 			unsigned int set, unsigned int clear);
 	int (*resize)(struct tty_struct *tty, struct tty_struct *real_tty,
 				struct winsize *ws);
+#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
+	defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
+	int (*kgdboc_port_startup)(struct tty_driver *driver, int line);
+	int (*kgdboc_port_shutdown)(struct tty_driver *driver, int line);
+#endif
 #ifdef CONFIG_CONSOLE_POLL
 	int (*poll_init)(struct tty_driver *driver, int line, char *options);
 	int (*poll_get_char)(struct tty_driver *driver, int line);
-- 
1.6.0

Re: [PATCH] [kgdb] Start kgdboc uart port to answer gdb break signal Ctrl+C without openning ttys.

[Sonic Zhang]

Yes, I am doing the same thing to deal with Ctrl+C as you expected. If
you have already got a solution, that's great. Please send out your
patch and I can implement UART specific code in bf5xx_serial driver
accordingly.

Sonic

On Fri, Sep 19, 2008 at 7:26 PM, Jason Wessel
<jason.wessel@windriver.com> wrote:
> I had been out for part of this week, and I started to look at your
> patches yesterday and will complete it some time today :-)
>
> The "control-c" without opening a tty is one I have a direct conflict
> with in that I have a completely different implementation of this that
> does the same thing.  In this other implementation (which I'll probably
> post publicly in response to this patch) there is a rx_poll hook for
> kgdboc to allow it to intercept and correctly process the control-c.
>
> How were you dealing with the control-c?  I assume it had to be in a
> similar sort of manner, because there two issues.
>
> 1) hook up the irq with the low level uart start
> 2) Issue a break on the control-c
>
> Certainly I would like to consolidate the implementations, which is why
> the review of the patch was not trivial.
>
> Thanks,
> Jason.
>
> Sonic Zhang wrote:
>> Hi Jason,
>>
>> Any comments?
>>
>> Sonic Zhang
>>
>>
>> On Wed, Sep 17, 2008 at 4:28 PM, sonic zhang <sonic.adi@gmail.com> wrote:
>>
>>>  Current kgdboc only configures the uart port in poll mode, which block
>>>  any gdb break signal Ctrl+C from taking effect till a tty on the port is
>>>  opened by an application. This patch introduces 2 hook functions in
>>>  struct tty_operations and uart_operations. The kgdboc port can be start
>>>  up without openning ttys after gdb is connected.
>>>
>>> Signed-off-by: Sonic Zhang <sonic.adi@gmail.com>
>>> ---
>>>  drivers/serial/kgdboc.c      |    8 +++++++-
>>>  drivers/serial/serial_core.c |   38 ++++++++++++++++++++++++++++++++++++++
>>>  include/linux/serial_core.h  |    9 +++++++++
>>>  include/linux/tty_driver.h   |    5 +++++
>>>  4 files changed, 59 insertions(+), 1 deletions(-)
>>>
>>> diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
>>> index eadc1ab..5d91f3d 100644
>>> --- a/drivers/serial/kgdboc.c
>>> +++ b/drivers/serial/kgdboc.c
>>> @@ -70,6 +70,9 @@ static int configure_kgdboc(void)
>>>
>>>        configured = 1;
>>>
>>> +       kgdb_tty_driver->ops->kgdboc_port_startup(kgdb_tty_driver,
>>> +                                       kgdb_tty_line);
>>> +
>>>        return 0;
>>>
>>>  noconfig:
>>> @@ -90,8 +93,11 @@ static int __init init_kgdboc(void)
>>>
>>>  static void cleanup_kgdboc(void)
>>>  {
>>> -       if (configured == 1)
>>> +       if (configured == 1) {
>>> +               kgdb_tty_driver->ops->kgdboc_port_shutdown(kgdb_tty_driver,
>>> +                                       kgdb_tty_line);
>>>                kgdb_unregister_io_module(&kgdboc_io_ops);
>>> +       }
>>>  }
>>>
>>>  static int kgdboc_get_char(void)
>>> diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
>>> index 73e9b8f..07f1b04 100644
>>> --- a/drivers/serial/serial_core.c
>>> +++ b/drivers/serial/serial_core.c
>>> @@ -2244,6 +2244,39 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
>>>        }
>>>  }
>>>
>>> +#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
>>> +       defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
>>> +static int uart_kgdboc_port_startup(struct tty_driver *driver, int line)
>>> +{
>>> +       struct uart_driver *drv = driver->driver_state;
>>> +       struct uart_state *state = drv->state + line;
>>> +       struct uart_port *port;
>>> +
>>> +       if (!state || !state->port)
>>> +               return -1;
>>> +
>>> +       port = state->port;
>>> +       if (port->ops->kgdboc_port_startup)
>>> +               return port->ops->kgdboc_port_startup(port);
>>> +       else
>>> +               return -1;
>>> +}
>>> +
>>> +static void uart_kgdboc_port_shutdown(struct tty_driver *driver, int line)
>>> +{
>>> +       struct uart_driver *drv = driver->driver_state;
>>> +       struct uart_state *state = drv->state + line;
>>> +       struct uart_port *port;
>>> +
>>> +       if (!state || !state->port)
>>> +               return;
>>> +
>>> +       port = state->port;
>>> +       if (port->ops->kgdboc_port_shutdown)
>>> +               port->ops->kgdboc_port_shutdown(port);
>>> +}
>>> +#endif
>>> +
>>>  #ifdef CONFIG_CONSOLE_POLL
>>>
>>>  static int uart_poll_init(struct tty_driver *driver, int line, char *options)
>>> @@ -2323,6 +2356,11 @@ static const struct tty_operations uart_ops = {
>>>  #endif
>>>        .tiocmget       = uart_tiocmget,
>>>        .tiocmset       = uart_tiocmset,
>>> +#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
>>> +       defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
>>> +       .kgdboc_port_startup    = uart_kgdboc_port_startup,
>>> +       .kgdboc_port_shutdown   = uart_kgdboc_port_shutdown,
>>> +#endif
>>>  #ifdef CONFIG_CONSOLE_POLL
>>>        .poll_init      = uart_poll_init,
>>>        .poll_get_char  = uart_poll_get_char,
>>> diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
>>> index 3b2f6c0..4a15311 100644
>>> --- a/include/linux/serial_core.h
>>> +++ b/include/linux/serial_core.h
>>> @@ -214,6 +214,15 @@ struct uart_ops {
>>>        void            (*config_port)(struct uart_port *, int);
>>>        int             (*verify_port)(struct uart_port *, struct serial_struct *);
>>>        int             (*ioctl)(struct uart_port *, unsigned int, unsigned long);
>>> +#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
>>> +       defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
>>> +       /*
>>> +        * Start up serial port earlier in kgdboc to support gdb break
>>> +        * signal Ctrl+C.
>>> +        */
>>> +       int             (*kgdboc_port_startup)(struct uart_port *);
>>> +       void            (*kgdboc_port_shutdown)(struct uart_port *);
>>> +#endif
>>>  #ifdef CONFIG_CONSOLE_POLL
>>>        void    (*poll_put_char)(struct uart_port *, unsigned char);
>>>        int             (*poll_get_char)(struct uart_port *);
>>> diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h
>>> index 16d2794..efd26cf 100644
>>> --- a/include/linux/tty_driver.h
>>> +++ b/include/linux/tty_driver.h
>>> @@ -220,6 +220,11 @@ struct tty_operations {
>>>                        unsigned int set, unsigned int clear);
>>>        int (*resize)(struct tty_struct *tty, struct tty_struct *real_tty,
>>>                                struct winsize *ws);
>>> +#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
>>> +       defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
>>> +       int (*kgdboc_port_startup)(struct tty_driver *driver, int line);
>>> +       int (*kgdboc_port_shutdown)(struct tty_driver *driver, int line);
>>> +#endif
>>>  #ifdef CONFIG_CONSOLE_POLL
>>>        int (*poll_init)(struct tty_driver *driver, int line, char *options);
>>>        int (*poll_get_char)(struct tty_driver *driver, int line);
>>> --
>>> 1.6.0
>>>
>>>
>>> --
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