* [PATCH v2] serial: meson: add Magic SysRq support
@ 2017-09-06 13:52 Yixun Lan
2017-10-20 8:10 ` Neil Armstrong
0 siblings, 1 reply; 4+ messages in thread
From: Yixun Lan @ 2017-09-06 13:52 UTC (permalink / raw)
To: linux-arm-kernel
This dirver try to implement the Magic SysRq support[1] for
Amlogic Inc's meson platfo
>From the hardware perspective, the UART IP can't detect the 'BREAK' command
clearly via the status register. Instead, we rely on the combination of
'FRAME_ERR bit && ch == 0', and it works fine.
[1] Documentation/admin-guide/sysrq.rst
Signed-off-by: Yixun Lan <dlan@gentoo.org>
---
Changes since v1 at [0]:
- add changelog & a few more comments
[0] https://patchwork.kernel.org/patch/9728475/
---
drivers/tty/serial/meson_uart.c | 18 ++++++++++++++++--
1 file changed, 16 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 42e4a4c7597f..3fea24bafd80 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -14,6 +14,10 @@
*
*/
+#if defined(CONFIG_SERIAL_MESON_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
#include <linux/clk.h>
#include <linux/console.h>
#include <linux/delay.h>
@@ -183,12 +187,12 @@ static void meson_receive_chars(struct uart_port *port)
{
struct tty_port *tport = &port->state->port;
char flag;
- u32 status, ch, mode;
+ u32 ostatus, status, ch, mode;
do {
flag = TTY_NORMAL;
port->icount.rx++;
- status = readl(port->membase + AML_UART_STATUS);
+ ostatus = status = readl(port->membase + AML_UART_STATUS);
if (status & AML_UART_ERR) {
if (status & AML_UART_TX_FIFO_WERR)
@@ -216,6 +220,16 @@ static void meson_receive_chars(struct uart_port *port)
ch = readl(port->membase + AML_UART_RFIFO);
ch &= 0xff;
+ if ((ostatus & AML_UART_FRAME_ERR) && (ch == 0)) {
+ port->icount.brk++;
+ flag = TTY_BREAK;
+ if (uart_handle_break(port))
+ continue;
+ }
+
+ if (uart_handle_sysrq_char(port, ch))
+ continue;
+
if ((status & port->ignore_status_mask) == 0)
tty_insert_flip_char(tport, ch, flag);
--
2.14.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH v2] serial: meson: add Magic SysRq support
2017-09-06 13:52 [PATCH v2] serial: meson: add Magic SysRq support Yixun Lan
@ 2017-10-20 8:10 ` Neil Armstrong
2017-10-20 8:32 ` Yixun Lan
0 siblings, 1 reply; 4+ messages in thread
From: Neil Armstrong @ 2017-10-20 8:10 UTC (permalink / raw)
To: linux-arm-kernel
Hi Yixun,
On 06/09/2017 15:52, Yixun Lan wrote:
> This dirver try to implement the Magic SysRq support[1] for
> Amlogic Inc's meson platfo
Please fix these typos.
> From the hardware perspective, the UART IP can't detect the 'BREAK' command
> clearly via the status register. Instead, we rely on the combination of
> 'FRAME_ERR bit && ch == 0', and it works fine.
>
> [1] Documentation/admin-guide/sysrq.rst
>
> Signed-off-by: Yixun Lan <dlan@gentoo.org>
>
> ---
> Changes since v1 at [0]:
> - add changelog & a few more comments
>
> [0] https://patchwork.kernel.org/patch/9728475/
> ---
> drivers/tty/serial/meson_uart.c | 18 ++++++++++++++++--
> 1 file changed, 16 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
> index 42e4a4c7597f..3fea24bafd80 100644
> --- a/drivers/tty/serial/meson_uart.c
> +++ b/drivers/tty/serial/meson_uart.c
> @@ -14,6 +14,10 @@
> *
> */
>
> +#if defined(CONFIG_SERIAL_MESON_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
> +#define SUPPORT_SYSRQ
> +#endif
> +
> #include <linux/clk.h>
> #include <linux/console.h>
> #include <linux/delay.h>
> @@ -183,12 +187,12 @@ static void meson_receive_chars(struct uart_port *port)
> {
> struct tty_port *tport = &port->state->port;
> char flag;
> - u32 status, ch, mode;
> + u32 ostatus, status, ch, mode;
>
> do {
> flag = TTY_NORMAL;
> port->icount.rx++;
> - status = readl(port->membase + AML_UART_STATUS);
> + ostatus = status = readl(port->membase + AML_UART_STATUS);
>
> if (status & AML_UART_ERR) {
> if (status & AML_UART_TX_FIFO_WERR)
> @@ -216,6 +220,16 @@ static void meson_receive_chars(struct uart_port *port)
> ch = readl(port->membase + AML_UART_RFIFO);
> ch &= 0xff;
>
> + if ((ostatus & AML_UART_FRAME_ERR) && (ch == 0)) {
> + port->icount.brk++;
> + flag = TTY_BREAK;
> + if (uart_handle_break(port))
> + continue;
> + }
> +
> + if (uart_handle_sysrq_char(port, ch))
> + continue;
> +
> if ((status & port->ignore_status_mask) == 0)
> tty_insert_flip_char(tport, ch, flag);
>
>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
^ permalink raw reply [flat|nested] 4+ messages in thread* [PATCH v2] serial: meson: add Magic SysRq support
2017-10-20 8:10 ` Neil Armstrong
@ 2017-10-20 8:32 ` Yixun Lan
2017-10-20 8:48 ` Neil Armstrong
0 siblings, 1 reply; 4+ messages in thread
From: Yixun Lan @ 2017-10-20 8:32 UTC (permalink / raw)
To: linux-arm-kernel
Hi Greg-KH
I think you've already accepted this patch (and merged into your git repo)
so, is it possible for you to amend the commit message? or do you want me
to send a PATCH v3 then?
On 10:10 Fri 20 Oct , Neil Armstrong wrote:
> Hi Yixun,
>
> On 06/09/2017 15:52, Yixun Lan wrote:
> > This dirver try to implement the Magic SysRq support[1] for
> > Amlogic Inc's meson platfo
>
> Please fix these typos.
>
oops, not sure why this line is broken..
s/platfo/platform./
and should squash next line .
> > From the hardware perspective, the UART IP can't detect the 'BREAK' command
> > clearly via the status register. Instead, we rely on the combination of
> > 'FRAME_ERR bit && ch == 0', and it works fine.
> >
> > [1] Documentation/admin-guide/sysrq.rst
> >
> > Signed-off-by: Yixun Lan <dlan@gentoo.org>
> >
> > ---
> > Changes since v1 at [0]:
> > - add changelog & a few more comments
> >
> > [0] https://patchwork.kernel.org/patch/9728475/
> > ---
> > drivers/tty/serial/meson_uart.c | 18 ++++++++++++++++--
> > 1 file changed, 16 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
> > index 42e4a4c7597f..3fea24bafd80 100644
> > --- a/drivers/tty/serial/meson_uart.c
> > +++ b/drivers/tty/serial/meson_uart.c
> > @@ -14,6 +14,10 @@
> > *
> > */
> >
> > +#if defined(CONFIG_SERIAL_MESON_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
> > +#define SUPPORT_SYSRQ
> > +#endif
> > +
> > #include <linux/clk.h>
> > #include <linux/console.h>
> > #include <linux/delay.h>
> > @@ -183,12 +187,12 @@ static void meson_receive_chars(struct uart_port *port)
> > {
> > struct tty_port *tport = &port->state->port;
> > char flag;
> > - u32 status, ch, mode;
> > + u32 ostatus, status, ch, mode;
> >
> > do {
> > flag = TTY_NORMAL;
> > port->icount.rx++;
> > - status = readl(port->membase + AML_UART_STATUS);
> > + ostatus = status = readl(port->membase + AML_UART_STATUS);
> >
> > if (status & AML_UART_ERR) {
> > if (status & AML_UART_TX_FIFO_WERR)
> > @@ -216,6 +220,16 @@ static void meson_receive_chars(struct uart_port *port)
> > ch = readl(port->membase + AML_UART_RFIFO);
> > ch &= 0xff;
> >
> > + if ((ostatus & AML_UART_FRAME_ERR) && (ch == 0)) {
> > + port->icount.brk++;
> > + flag = TTY_BREAK;
> > + if (uart_handle_break(port))
> > + continue;
> > + }
> > +
> > + if (uart_handle_sysrq_char(port, ch))
> > + continue;
> > +
> > if ((status & port->ignore_status_mask) == 0)
> > tty_insert_flip_char(tport, ch, flag);
> >
> >
>
> Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
>
> _______________________________________________
> linux-amlogic mailing list
> linux-amlogic at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-amlogic
--
Yixun Lan (dlan)
Gentoo Linux Developer
GPG Key ID AABEFD55
^ permalink raw reply [flat|nested] 4+ messages in thread* [PATCH v2] serial: meson: add Magic SysRq support
2017-10-20 8:32 ` Yixun Lan
@ 2017-10-20 8:48 ` Neil Armstrong
0 siblings, 0 replies; 4+ messages in thread
From: Neil Armstrong @ 2017-10-20 8:48 UTC (permalink / raw)
To: linux-arm-kernel
I Yixun,
On 20/10/2017 10:32, Yixun Lan wrote:
> Hi Greg-KH
>
> I think you've already accepted this patch (and merged into your git repo)
>
> so, is it possible for you to amend the commit message? or do you want me
> to send a PATCH v3 then?
I was not aware greg applied it, no need to amen anything, ignore my tag.
Neil
>
> On 10:10 Fri 20 Oct , Neil Armstrong wrote:
>> Hi Yixun,
>>
>> On 06/09/2017 15:52, Yixun Lan wrote:
>>> This dirver try to implement the Magic SysRq support[1] for
>>> Amlogic Inc's meson platfo
>>
>> Please fix these typos.
>>
> oops, not sure why this line is broken..
>
> s/platfo/platform./
> and should squash next line .
>
>>> From the hardware perspective, the UART IP can't detect the 'BREAK' command
>>> clearly via the status register. Instead, we rely on the combination of
>>> 'FRAME_ERR bit && ch == 0', and it works fine.
>>>
>>> [1] Documentation/admin-guide/sysrq.rst
>>>
>>> Signed-off-by: Yixun Lan <dlan@gentoo.org>
>>>
>>> ---
>>> Changes since v1 at [0]:
>>> - add changelog & a few more comments
>>>
>>> [0] https://patchwork.kernel.org/patch/9728475/
>>> ---
>>> drivers/tty/serial/meson_uart.c | 18 ++++++++++++++++--
>>> 1 file changed, 16 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
>>> index 42e4a4c7597f..3fea24bafd80 100644
>>> --- a/drivers/tty/serial/meson_uart.c
>>> +++ b/drivers/tty/serial/meson_uart.c
>>> @@ -14,6 +14,10 @@
>>> *
>>> */
>>>
>>> +#if defined(CONFIG_SERIAL_MESON_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
>>> +#define SUPPORT_SYSRQ
>>> +#endif
>>> +
>>> #include <linux/clk.h>
>>> #include <linux/console.h>
>>> #include <linux/delay.h>
>>> @@ -183,12 +187,12 @@ static void meson_receive_chars(struct uart_port *port)
>>> {
>>> struct tty_port *tport = &port->state->port;
>>> char flag;
>>> - u32 status, ch, mode;
>>> + u32 ostatus, status, ch, mode;
>>>
>>> do {
>>> flag = TTY_NORMAL;
>>> port->icount.rx++;
>>> - status = readl(port->membase + AML_UART_STATUS);
>>> + ostatus = status = readl(port->membase + AML_UART_STATUS);
>>>
>>> if (status & AML_UART_ERR) {
>>> if (status & AML_UART_TX_FIFO_WERR)
>>> @@ -216,6 +220,16 @@ static void meson_receive_chars(struct uart_port *port)
>>> ch = readl(port->membase + AML_UART_RFIFO);
>>> ch &= 0xff;
>>>
>>> + if ((ostatus & AML_UART_FRAME_ERR) && (ch == 0)) {
>>> + port->icount.brk++;
>>> + flag = TTY_BREAK;
>>> + if (uart_handle_break(port))
>>> + continue;
>>> + }
>>> +
>>> + if (uart_handle_sysrq_char(port, ch))
>>> + continue;
>>> +
>>> if ((status & port->ignore_status_mask) == 0)
>>> tty_insert_flip_char(tport, ch, flag);
>>>
>>>
>>
>> Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
>>
>> _______________________________________________
>> linux-amlogic mailing list
>> linux-amlogic at lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-amlogic
>
^ permalink raw reply [flat|nested] 4+ messages in thread
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2017-09-06 13:52 [PATCH v2] serial: meson: add Magic SysRq support Yixun Lan
2017-10-20 8:10 ` Neil Armstrong
2017-10-20 8:32 ` Yixun Lan
2017-10-20 8:48 ` Neil Armstrong
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