| Message ID | 1439912592-14779-1-git-send-email-fabio.estevam@freescale.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Aug 18, 2015 at 12:43:12PM -0300, Fabio Estevam wrote: > This reverts commit 9e7b399d6528eac33a6fbfceb2b92af209c3454d. > > Commit ("9e7b399d6528ea") causes the following warning and sometimes > also hangs the system: > > ------------[ cut here ]------------ > WARNING: CPU: 0 PID: 0 at kernel/locking/mutex.c:868 mutex_trylock+0x20c/0x22c() > DEBUG_LOCKS_WARN_ON(in_interrupt()) > Modules linked in: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.2.0-rc7-next-20150818-00001-g14418a6 #4 > Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) > Backtrace: > [<80012f08>] (dump_backtrace) from [<800130a4>] (show_stack+0x18/0x1c) > r6:00000364 r5:00000000 r4:00000000 r3:00000000 > [<8001308c>] (show_stack) from [<807902b8>] (dump_stack+0x88/0xa4) > [<80790230>] (dump_stack) from [<8002a604>] (warn_slowpath_common+0x80/0xbc) > r5:807945c4 r4:80ab3b50 > [<8002a584>] (warn_slowpath_common) from [<8002a6e4>] (warn_slowpath_fmt+0x38/0x40) > r8:00000000 r7:8131100c r6:8054c3cc r5:8131300c r4:80b0a570 > [<8002a6b0>] (warn_slowpath_fmt) from [<807945c4>] (mutex_trylock+0x20c/0x22c) > r3:8095d0d8 r2:8095ab28 > [<807943b8>] (mutex_trylock) from [<8054c3cc>] (clk_prepare_lock+0x14/0xf4) > r7:8131100c r6:be3f0c80 r5:00000037 r4:be3f0c80 > [<8054c3b8>] (clk_prepare_lock) from [<8054dbfc>] (clk_prepare+0x18/0x30) > r5:00000037 r4:be3f0c80 > [<8054dbe4>] (clk_prepare) from [<8036a600>] (imx_console_write+0x30/0x244) > r4:812d0bc8 r3:8132b9a4 > > To reproduce the problem we only need to let the board idle for something > like 30 seconds. hmmm.. I really did not see this one. Looking at the code looks like we could be atomic in some of the uart console callbacks. For this one: Reviewed-by: Eduardo Valentin <edubezval@gmail.com> Did you try the runtime pm patch on your end? BR, > > Tested on a imx6q-sabresd. > > Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> > --- > drivers/tty/serial/imx.c | 20 ++++++++++++++------ > 1 file changed, 14 insertions(+), 6 deletions(-) > > diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c > index fe3d41c..d0388a0 100644 > --- a/drivers/tty/serial/imx.c > +++ b/drivers/tty/serial/imx.c > @@ -1631,12 +1631,12 @@ imx_console_write(struct console *co, const char *s, unsigned int count) > int locked = 1; > int retval; > > - retval = clk_prepare_enable(sport->clk_per); > + retval = clk_enable(sport->clk_per); > if (retval) > return; > - retval = clk_prepare_enable(sport->clk_ipg); > + retval = clk_enable(sport->clk_ipg); > if (retval) { > - clk_disable_unprepare(sport->clk_per); > + clk_disable(sport->clk_per); > return; > } > > @@ -1675,8 +1675,8 @@ imx_console_write(struct console *co, const char *s, unsigned int count) > if (locked) > spin_unlock_irqrestore(&sport->port.lock, flags); > > - clk_disable_unprepare(sport->clk_ipg); > - clk_disable_unprepare(sport->clk_per); > + clk_disable(sport->clk_ipg); > + clk_disable(sport->clk_per); > } > > /* > @@ -1777,7 +1777,15 @@ imx_console_setup(struct console *co, char *options) > > retval = uart_set_options(&sport->port, co, baud, parity, bits, flow); > > - clk_disable_unprepare(sport->clk_ipg); > + clk_disable(sport->clk_ipg); > + if (retval) { > + clk_unprepare(sport->clk_ipg); > + goto error_console; > + } > + > + retval = clk_prepare(sport->clk_per); > + if (retval) > + clk_disable_unprepare(sport->clk_ipg); > > error_console: > return retval; > -- > 1.9.1 >
On Tue, Aug 18, 2015 at 8:33 PM, Eduardo Valentin <edubezval@gmail.com> wrote: > hmmm.. I really did not see this one. Looking at the code looks like we > could be atomic in some of the uart console callbacks. > > For this one: > > Reviewed-by: Eduardo Valentin <edubezval@gmail.com> > > Did you try the runtime pm patch on your end? I have only tested linux-next.
Hi Greg, On Tue, Aug 18, 2015 at 12:43 PM, Fabio Estevam <fabio.estevam@freescale.com> wrote: > This reverts commit 9e7b399d6528eac33a6fbfceb2b92af209c3454d. > > Commit ("9e7b399d6528ea") causes the following warning and sometimes > also hangs the system: > > ------------[ cut here ]------------ > WARNING: CPU: 0 PID: 0 at kernel/locking/mutex.c:868 mutex_trylock+0x20c/0x22c() > DEBUG_LOCKS_WARN_ON(in_interrupt()) > Modules linked in: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.2.0-rc7-next-20150818-00001-g14418a6 #4 > Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) > Backtrace: > [<80012f08>] (dump_backtrace) from [<800130a4>] (show_stack+0x18/0x1c) > r6:00000364 r5:00000000 r4:00000000 r3:00000000 > [<8001308c>] (show_stack) from [<807902b8>] (dump_stack+0x88/0xa4) > [<80790230>] (dump_stack) from [<8002a604>] (warn_slowpath_common+0x80/0xbc) > r5:807945c4 r4:80ab3b50 > [<8002a584>] (warn_slowpath_common) from [<8002a6e4>] (warn_slowpath_fmt+0x38/0x40) > r8:00000000 r7:8131100c r6:8054c3cc r5:8131300c r4:80b0a570 > [<8002a6b0>] (warn_slowpath_fmt) from [<807945c4>] (mutex_trylock+0x20c/0x22c) > r3:8095d0d8 r2:8095ab28 > [<807943b8>] (mutex_trylock) from [<8054c3cc>] (clk_prepare_lock+0x14/0xf4) > r7:8131100c r6:be3f0c80 r5:00000037 r4:be3f0c80 > [<8054c3b8>] (clk_prepare_lock) from [<8054dbfc>] (clk_prepare+0x18/0x30) > r5:00000037 r4:be3f0c80 > [<8054dbe4>] (clk_prepare) from [<8036a600>] (imx_console_write+0x30/0x244) > r4:812d0bc8 r3:8132b9a4 > > To reproduce the problem we only need to let the board idle for something > like 30 seconds. > > Tested on a imx6q-sabresd. > > Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Could you please consider applying this one for 4.3-rc? Thanks
Am Samstag, den 26.09.2015, 17:14 -0300 schrieb Fabio Estevam: > Hi Greg, > > On Tue, Aug 18, 2015 at 12:43 PM, Fabio Estevam > <fabio.estevam@freescale.com> wrote: > > This reverts commit 9e7b399d6528eac33a6fbfceb2b92af209c3454d. > > > > Commit ("9e7b399d6528ea") causes the following warning and sometimes > > also hangs the system: > > > > ------------[ cut here ]------------ > > WARNING: CPU: 0 PID: 0 at kernel/locking/mutex.c:868 mutex_trylock+0x20c/0x22c() > > DEBUG_LOCKS_WARN_ON(in_interrupt()) > > Modules linked in: > > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.2.0-rc7-next-20150818-00001-g14418a6 #4 > > Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) > > Backtrace: > > [<80012f08>] (dump_backtrace) from [<800130a4>] (show_stack+0x18/0x1c) > > r6:00000364 r5:00000000 r4:00000000 r3:00000000 > > [<8001308c>] (show_stack) from [<807902b8>] (dump_stack+0x88/0xa4) > > [<80790230>] (dump_stack) from [<8002a604>] (warn_slowpath_common+0x80/0xbc) > > r5:807945c4 r4:80ab3b50 > > [<8002a584>] (warn_slowpath_common) from [<8002a6e4>] (warn_slowpath_fmt+0x38/0x40) > > r8:00000000 r7:8131100c r6:8054c3cc r5:8131300c r4:80b0a570 > > [<8002a6b0>] (warn_slowpath_fmt) from [<807945c4>] (mutex_trylock+0x20c/0x22c) > > r3:8095d0d8 r2:8095ab28 > > [<807943b8>] (mutex_trylock) from [<8054c3cc>] (clk_prepare_lock+0x14/0xf4) > > r7:8131100c r6:be3f0c80 r5:00000037 r4:be3f0c80 > > [<8054c3b8>] (clk_prepare_lock) from [<8054dbfc>] (clk_prepare+0x18/0x30) > > r5:00000037 r4:be3f0c80 > > [<8054dbe4>] (clk_prepare) from [<8036a600>] (imx_console_write+0x30/0x244) > > r4:812d0bc8 r3:8132b9a4 > > > > To reproduce the problem we only need to let the board idle for something > > like 30 seconds. > > > > Tested on a imx6q-sabresd. > > > > Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> > > Could you please consider applying this one for 4.3-rc? > To put a bit more wight behind this: without this revert i.MX6 with an active serial console boards are not even able to boot into userspace. Please apply this as a critical fix. Regards, Lucas
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index fe3d41c..d0388a0 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -1631,12 +1631,12 @@ imx_console_write(struct console *co, const char *s, unsigned int count) int locked = 1; int retval; - retval = clk_prepare_enable(sport->clk_per); + retval = clk_enable(sport->clk_per); if (retval) return; - retval = clk_prepare_enable(sport->clk_ipg); + retval = clk_enable(sport->clk_ipg); if (retval) { - clk_disable_unprepare(sport->clk_per); + clk_disable(sport->clk_per); return; } @@ -1675,8 +1675,8 @@ imx_console_write(struct console *co, const char *s, unsigned int count) if (locked) spin_unlock_irqrestore(&sport->port.lock, flags); - clk_disable_unprepare(sport->clk_ipg); - clk_disable_unprepare(sport->clk_per); + clk_disable(sport->clk_ipg); + clk_disable(sport->clk_per); } /* @@ -1777,7 +1777,15 @@ imx_console_setup(struct console *co, char *options) retval = uart_set_options(&sport->port, co, baud, parity, bits, flow); - clk_disable_unprepare(sport->clk_ipg); + clk_disable(sport->clk_ipg); + if (retval) { + clk_unprepare(sport->clk_ipg); + goto error_console; + } + + retval = clk_prepare(sport->clk_per); + if (retval) + clk_disable_unprepare(sport->clk_ipg); error_console: return retval;
This reverts commit 9e7b399d6528eac33a6fbfceb2b92af209c3454d. Commit ("9e7b399d6528ea") causes the following warning and sometimes also hangs the system: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at kernel/locking/mutex.c:868 mutex_trylock+0x20c/0x22c() DEBUG_LOCKS_WARN_ON(in_interrupt()) Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.2.0-rc7-next-20150818-00001-g14418a6 #4 Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) Backtrace: [<80012f08>] (dump_backtrace) from [<800130a4>] (show_stack+0x18/0x1c) r6:00000364 r5:00000000 r4:00000000 r3:00000000 [<8001308c>] (show_stack) from [<807902b8>] (dump_stack+0x88/0xa4) [<80790230>] (dump_stack) from [<8002a604>] (warn_slowpath_common+0x80/0xbc) r5:807945c4 r4:80ab3b50 [<8002a584>] (warn_slowpath_common) from [<8002a6e4>] (warn_slowpath_fmt+0x38/0x40) r8:00000000 r7:8131100c r6:8054c3cc r5:8131300c r4:80b0a570 [<8002a6b0>] (warn_slowpath_fmt) from [<807945c4>] (mutex_trylock+0x20c/0x22c) r3:8095d0d8 r2:8095ab28 [<807943b8>] (mutex_trylock) from [<8054c3cc>] (clk_prepare_lock+0x14/0xf4) r7:8131100c r6:be3f0c80 r5:00000037 r4:be3f0c80 [<8054c3b8>] (clk_prepare_lock) from [<8054dbfc>] (clk_prepare+0x18/0x30) r5:00000037 r4:be3f0c80 [<8054dbe4>] (clk_prepare) from [<8036a600>] (imx_console_write+0x30/0x244) r4:812d0bc8 r3:8132b9a4 To reproduce the problem we only need to let the board idle for something like 30 seconds. Tested on a imx6q-sabresd. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> --- drivers/tty/serial/imx.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-)