commit 9e7b399d6528 ("serial: imx: remove unbalanced clk_prepare").
Otherwise below warning happen since there are some printk logs in
interrupt.
[ 14.868319] udevd[501]: starting version 182
[ 16.386107] random: nonblocking pool is initialized
[ 16.386123] ------------[ cut here ]------------
[ 16.386140] WARNING: CPU: 0 PID: 501 at kernel/locking/mutex.c:868 mutex_trylock+0x210/0x230()
[ 16.386146] DEBUG_LOCKS_WARN_ON(in_interrupt())
[ 16.386149] Modules linked in:
[ 16.386157] CPU: 0 PID: 501 Comm: udevd Not tainted 4.3.0-rc1-00014-gf843df8 #28
[ 16.386160] Hardware name: Freescale i.MX6 SoloX (Device Tree)
[ 16.386165] Backtrace:
[ 16.386182] [<c0013e98>] (dump_backtrace) from [<c0014090>] (show_stack+0x18/0x1c)
[ 16.386192] r6:c0af1840 r5:00000000 r4:00000000 r3:00000000
[ 16.386201] [<c0014078>] (show_stack) from [<c02d4af8>] (dump_stack+0x8c/0xa4)
[ 16.386216] [<c02d4a6c>] (dump_stack) from [<c002be14>] (warn_slowpath_common+0x80/0xbc)
[ 16.386225] r6:c07b1ccc r5:00000009 r4:edcf5c60 r3:00000001
[ 16.386234] [<c002bd94>] (warn_slowpath_common) from [<c002be88>] (warn_slowpath_fmt+0x38/0x40)
[ 16.386246] r8:c0564694 r7:eeb76880 r6:c13323ec r5:00000001 r4:c0976990
[ 16.386255] [<c002be54>] (warn_slowpath_fmt) from [<c07b1ccc>] (mutex_trylock+0x210/0x230)
[ 16.386261] r3:c0978f50 r2:c0976990
[ 16.386264] r4:c0b29a70
[ 16.386278] [<c07b1abc>] (mutex_trylock) from [<c0564694>] (clk_prepare_lock+0x14/0xf4)
[ 16.386289] r8:c133000c r7:eeb76880 r6:00000037 r5:c12efbc8 r4:eeb76880
[ 16.386297] [<c0564680>] (clk_prepare_lock) from [<c0565e04>] (clk_prepare+0x18/0x38)
[ 16.386303] r5:c12efbc8 r4:eeb76880
[ 16.386311] [<c0565dec>] (clk_prepare) from [<c0379a90>] (imx_console_write+0x34/0x248)
[ 16.386317] r4:ee999c10 r3:c134a92c
[ 16.386329] [<c0379a5c>] (imx_console_write) from [<c007ac74>] (call_console_drivers.constprop.25+0xe0/0x104)
[ 16.386342] r10:c07b938c r9:00000000 r8:c133000c r7:00000037 r6:edcf4000 r5:c12ef6c0
[ 16.386345] r4:c0afef38
[ 16.386355] [<c007ab94>] (call_console_drivers.constprop.25) from [<c007be84>] (console_unlock+0x3fc/0x57c)
[ 16.386367] r10:c132fff0 r9:00000100 r8:00000037 r7:00000000 r6:00000005 r5:c12f4df0
Signed-off-by: Robin Gong <[email protected]>
---
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 Wed, Nov 4, 2015 at 12:58 AM, Robin Gong <[email protected]> wrote:
> commit 9e7b399d6528 ("serial: imx: remove unbalanced clk_prepare").
> Otherwise below warning happen since there are some printk logs in
> interrupt.
This has already been reverted since v4.3-rc5.
From: Robin Gong <[email protected]> Sent: Wednesday, November 04, 2015 10:58 AM
> To: [email protected]; [email protected]
> Cc: Duan Fugang-B38611; [email protected]; linux-
> [email protected]
> Subject: [PATCH v1] Revert "serial: imx: remove unbalanced clk_prepare"
>
> commit 9e7b399d6528 ("serial: imx: remove unbalanced clk_prepare").
> Otherwise below warning happen since there are some printk logs in
> interrupt.
>
> [ 14.868319] udevd[501]: starting version 182
> [ 16.386107] random: nonblocking pool is initialized
> [ 16.386123] ------------[ cut here ]------------
> [ 16.386140] WARNING: CPU: 0 PID: 501 at kernel/locking/mutex.c:868
> mutex_trylock+0x210/0x230()
> [ 16.386146] DEBUG_LOCKS_WARN_ON(in_interrupt())
> [ 16.386149] Modules linked in:
> [ 16.386157] CPU: 0 PID: 501 Comm: udevd Not tainted 4.3.0-rc1-00014-
> gf843df8 #28
> [ 16.386160] Hardware name: Freescale i.MX6 SoloX (Device Tree)
> [ 16.386165] Backtrace:
> [ 16.386182] [<c0013e98>] (dump_backtrace) from [<c0014090>]
> (show_stack+0x18/0x1c)
> [ 16.386192] r6:c0af1840 r5:00000000 r4:00000000 r3:00000000
> [ 16.386201] [<c0014078>] (show_stack) from [<c02d4af8>]
> (dump_stack+0x8c/0xa4)
> [ 16.386216] [<c02d4a6c>] (dump_stack) from [<c002be14>]
> (warn_slowpath_common+0x80/0xbc)
> [ 16.386225] r6:c07b1ccc r5:00000009 r4:edcf5c60 r3:00000001
> [ 16.386234] [<c002bd94>] (warn_slowpath_common) from [<c002be88>]
> (warn_slowpath_fmt+0x38/0x40)
> [ 16.386246] r8:c0564694 r7:eeb76880 r6:c13323ec r5:00000001
> r4:c0976990
> [ 16.386255] [<c002be54>] (warn_slowpath_fmt) from [<c07b1ccc>]
> (mutex_trylock+0x210/0x230)
> [ 16.386261] r3:c0978f50 r2:c0976990
> [ 16.386264] r4:c0b29a70
> [ 16.386278] [<c07b1abc>] (mutex_trylock) from [<c0564694>]
> (clk_prepare_lock+0x14/0xf4)
> [ 16.386289] r8:c133000c r7:eeb76880 r6:00000037 r5:c12efbc8
> r4:eeb76880
> [ 16.386297] [<c0564680>] (clk_prepare_lock) from [<c0565e04>]
> (clk_prepare+0x18/0x38)
> [ 16.386303] r5:c12efbc8 r4:eeb76880
> [ 16.386311] [<c0565dec>] (clk_prepare) from [<c0379a90>]
> (imx_console_write+0x34/0x248)
> [ 16.386317] r4:ee999c10 r3:c134a92c
> [ 16.386329] [<c0379a5c>] (imx_console_write) from [<c007ac74>]
> (call_console_drivers.constprop.25+0xe0/0x104)
> [ 16.386342] r10:c07b938c r9:00000000 r8:c133000c r7:00000037
> r6:edcf4000 r5:c12ef6c0
> [ 16.386345] r4:c0afef38
> [ 16.386355] [<c007ab94>] (call_console_drivers.constprop.25) from
> [<c007be84>] (console_unlock+0x3fc/0x57c)
> [ 16.386367] r10:c132fff0 r9:00000100 r8:00000037 r7:00000000
> r6:00000005 r5:c12f4df0
>
> Signed-off-by: Robin Gong <[email protected]>
> ---
> drivers/tty/serial/imx.c | 20 ++++++++++++++------
> 1 file changed, 14 insertions(+), 6 deletions(-)
I remember there had patch for this.
On Wed, Nov 04, 2015 at 01:39:17AM -0200, Fabio Estevam wrote:
> On Wed, Nov 4, 2015 at 12:58 AM, Robin Gong <[email protected]> wrote:
> > commit 9e7b399d6528 ("serial: imx: remove unbalanced clk_prepare").
> > Otherwise below warning happen since there are some printk logs in
> > interrupt.
>
> This has already been reverted since v4.3-rc5.
That's great, please ignore this patch.