[PATCH RESEND 0/2] Misc OMAP GPIO/UART fixes

[PATCH RESEND 0/2] Misc OMAP GPIO/UART fixes

[Judith Mendez]

This patch series carries some miscellaneous
OMAP driver fixes for GPIO and UART drivers.

For GPIO, add gpio_enable and gpio_disable calls
to gpio-omap which fixes an issue where if there
is an irq storm, serial console is unresponsive.

For UART, move pm_runtime_get_sync since the
current order of omap_8250_rx_dma_flush and
pm_runtime_get_sync calls are set in a way that
when omap_8250_shutdown returns, dma->rx_running
is set and this causes issues next time the UART
is re-opened.

Changes since v1:
- Fix CC list
- Drop Fixes tag

Judith Mendez (2):
  gpio: omap: Add omap_gpio_disable/enable_irq calls
  serial: 8250: omap: Move pm_runtime_get_sync

 drivers/gpio/gpio-omap.c            | 29 +++++++++++++++++++++++++++++
 drivers/tty/serial/8250/8250_omap.c |  4 ++--
 2 files changed, 31 insertions(+), 2 deletions(-)


base-commit: f45840d172a06d07a1a408b38bdb0be9ab3fd8cb
-- 
2.47.0

[PATCH RESEND 1/2] gpio: omap: Add omap_gpio_disable/enable_irq calls

[Judith Mendez]

Add omap_gpio_disable_irq and omap_gpio_enable_irq
calls in gpio-omap.

Currently, kernel cannot disable gpio interrupts in
case of a irq storm, so add omap_gpio_disable_irq
so that interrupts can be disabled/enabled.

Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Judith Mendez <jm@ti.com>
---
 drivers/gpio/gpio-omap.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index 76d5d87e9681..913e6ece1238 100644
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -711,6 +711,31 @@ static void omap_gpio_unmask_irq(struct irq_data *d)
 	raw_spin_unlock_irqrestore(&bank->lock, flags);
 }
 
+static void omap_gpio_set_irq(struct irq_data *d, bool enable)
+{
+	struct gpio_bank *bank = omap_irq_data_get_bank(d);
+	unsigned int offset = d->hwirq;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&bank->lock, flags);
+	omap_set_gpio_irqenable(bank, offset, enable);
+	raw_spin_unlock_irqrestore(&bank->lock, flags);
+}
+
+static void omap_gpio_disable_irq(struct irq_data *d)
+{
+	bool enable = 1;
+
+	omap_gpio_set_irq(d, !enable);
+}
+
+static void omap_gpio_enable_irq(struct irq_data *d)
+{
+	bool enable = 1;
+
+	omap_gpio_set_irq(d, enable);
+}
+
 static void omap_gpio_irq_print_chip(struct irq_data *d, struct seq_file *p)
 {
 	struct gpio_bank *bank = omap_irq_data_get_bank(d);
@@ -723,6 +748,8 @@ static const struct irq_chip omap_gpio_irq_chip = {
 	.irq_shutdown = omap_gpio_irq_shutdown,
 	.irq_mask = omap_gpio_mask_irq,
 	.irq_unmask = omap_gpio_unmask_irq,
+	.irq_disable = omap_gpio_disable_irq,
+	.irq_enable = omap_gpio_enable_irq,
 	.irq_set_type = omap_gpio_irq_type,
 	.irq_set_wake = omap_gpio_wake_enable,
 	.irq_bus_lock = omap_gpio_irq_bus_lock,
@@ -737,6 +764,8 @@ static const struct irq_chip omap_gpio_irq_chip_nowake = {
 	.irq_shutdown = omap_gpio_irq_shutdown,
 	.irq_mask = omap_gpio_mask_irq,
 	.irq_unmask = omap_gpio_unmask_irq,
+	.irq_disable = omap_gpio_disable_irq,
+	.irq_enable = omap_gpio_enable_irq,
 	.irq_set_type = omap_gpio_irq_type,
 	.irq_bus_lock = omap_gpio_irq_bus_lock,
 	.irq_bus_sync_unlock = gpio_irq_bus_sync_unlock,
-- 
2.47.0

Re: [PATCH RESEND 1/2] gpio: omap: Add omap_gpio_disable/enable_irq calls

[Andrew Davis]

On 10/11/24 12:33 PM, Judith Mendez wrote:
> Add omap_gpio_disable_irq and omap_gpio_enable_irq
> calls in gpio-omap.
> 
> Currently, kernel cannot disable gpio interrupts in
> case of a irq storm, so add omap_gpio_disable_irq
> so that interrupts can be disabled/enabled.
> 
> Signed-off-by: Bin Liu <b-liu@ti.com>
> Signed-off-by: Judith Mendez <jm@ti.com>
> ---
>   drivers/gpio/gpio-omap.c | 29 +++++++++++++++++++++++++++++
>   1 file changed, 29 insertions(+)
> 
> diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
> index 76d5d87e9681..913e6ece1238 100644
> --- a/drivers/gpio/gpio-omap.c
> +++ b/drivers/gpio/gpio-omap.c
> @@ -711,6 +711,31 @@ static void omap_gpio_unmask_irq(struct irq_data *d)
>   	raw_spin_unlock_irqrestore(&bank->lock, flags);
>   }
>   
> +static void omap_gpio_set_irq(struct irq_data *d, bool enable)
> +{
> +	struct gpio_bank *bank = omap_irq_data_get_bank(d);
> +	unsigned int offset = d->hwirq;
> +	unsigned long flags;
> +
> +	raw_spin_lock_irqsave(&bank->lock, flags);
> +	omap_set_gpio_irqenable(bank, offset, enable);
> +	raw_spin_unlock_irqrestore(&bank->lock, flags);
> +}
> +
> +static void omap_gpio_disable_irq(struct irq_data *d)
> +{
> +	bool enable = 1;
> +
> +	omap_gpio_set_irq(d, !enable);

Seems like an odd way to make "false", why not:

omap_gpio_set_irq(d, false);

Andrew

> +}
> +
> +static void omap_gpio_enable_irq(struct irq_data *d)
> +{
> +	bool enable = 1;
> +
> +	omap_gpio_set_irq(d, enable);
> +}
> +
>   static void omap_gpio_irq_print_chip(struct irq_data *d, struct seq_file *p)
>   {
>   	struct gpio_bank *bank = omap_irq_data_get_bank(d);
> @@ -723,6 +748,8 @@ static const struct irq_chip omap_gpio_irq_chip = {
>   	.irq_shutdown = omap_gpio_irq_shutdown,
>   	.irq_mask = omap_gpio_mask_irq,
>   	.irq_unmask = omap_gpio_unmask_irq,
> +	.irq_disable = omap_gpio_disable_irq,
> +	.irq_enable = omap_gpio_enable_irq,
>   	.irq_set_type = omap_gpio_irq_type,
>   	.irq_set_wake = omap_gpio_wake_enable,
>   	.irq_bus_lock = omap_gpio_irq_bus_lock,
> @@ -737,6 +764,8 @@ static const struct irq_chip omap_gpio_irq_chip_nowake = {
>   	.irq_shutdown = omap_gpio_irq_shutdown,
>   	.irq_mask = omap_gpio_mask_irq,
>   	.irq_unmask = omap_gpio_unmask_irq,
> +	.irq_disable = omap_gpio_disable_irq,
> +	.irq_enable = omap_gpio_enable_irq,
>   	.irq_set_type = omap_gpio_irq_type,
>   	.irq_bus_lock = omap_gpio_irq_bus_lock,
>   	.irq_bus_sync_unlock = gpio_irq_bus_sync_unlock,

Re: [PATCH RESEND 1/2] gpio: omap: Add omap_gpio_disable/enable_irq calls

[Judith Mendez]

Hi Andrew,

On 10/11/24 2:07 PM, Andrew Davis wrote:
> On 10/11/24 12:33 PM, Judith Mendez wrote:
>> Add omap_gpio_disable_irq and omap_gpio_enable_irq
>> calls in gpio-omap.
>>
>> Currently, kernel cannot disable gpio interrupts in
>> case of a irq storm, so add omap_gpio_disable_irq
>> so that interrupts can be disabled/enabled.
>>
>> Signed-off-by: Bin Liu <b-liu@ti.com>
>> Signed-off-by: Judith Mendez <jm@ti.com>
>> ---
>>   drivers/gpio/gpio-omap.c | 29 +++++++++++++++++++++++++++++
>>   1 file changed, 29 insertions(+)
>>
>> diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
>> index 76d5d87e9681..913e6ece1238 100644
>> --- a/drivers/gpio/gpio-omap.c
>> +++ b/drivers/gpio/gpio-omap.c
>> @@ -711,6 +711,31 @@ static void omap_gpio_unmask_irq(struct irq_data *d)
>>       raw_spin_unlock_irqrestore(&bank->lock, flags);
>>   }
>> +static void omap_gpio_set_irq(struct irq_data *d, bool enable)
>> +{
>> +    struct gpio_bank *bank = omap_irq_data_get_bank(d);
>> +    unsigned int offset = d->hwirq;
>> +    unsigned long flags;
>> +
>> +    raw_spin_lock_irqsave(&bank->lock, flags);
>> +    omap_set_gpio_irqenable(bank, offset, enable);
>> +    raw_spin_unlock_irqrestore(&bank->lock, flags);
>> +}
>> +
>> +static void omap_gpio_disable_irq(struct irq_data *d)
>> +{
>> +    bool enable = 1;
>> +
>> +    omap_gpio_set_irq(d, !enable);
> 
> Seems like an odd way to make "false", why not:
> 
> omap_gpio_set_irq(d, false);

Thanks for your review, you are right, but I will
be reverting to the original patch format. Where we do
not used wrappers function around omap_gpio_set_irq().

~ Judith

> 
> Andrew
> 
>> +}
>> +
>> +static void omap_gpio_enable_irq(struct irq_data *d)
>> +{
>> +    bool enable = 1;
>> +
>> +    omap_gpio_set_irq(d, enable);
>> +}
>> +
>>   static void omap_gpio_irq_print_chip(struct irq_data *d, struct 
>> seq_file *p)
>>   {
>>       struct gpio_bank *bank = omap_irq_data_get_bank(d);
>> @@ -723,6 +748,8 @@ static const struct irq_chip omap_gpio_irq_chip = {
>>       .irq_shutdown = omap_gpio_irq_shutdown,
>>       .irq_mask = omap_gpio_mask_irq,
>>       .irq_unmask = omap_gpio_unmask_irq,
>> +    .irq_disable = omap_gpio_disable_irq,
>> +    .irq_enable = omap_gpio_enable_irq,
>>       .irq_set_type = omap_gpio_irq_type,
>>       .irq_set_wake = omap_gpio_wake_enable,
>>       .irq_bus_lock = omap_gpio_irq_bus_lock,
>> @@ -737,6 +764,8 @@ static const struct irq_chip 
>> omap_gpio_irq_chip_nowake = {
>>       .irq_shutdown = omap_gpio_irq_shutdown,
>>       .irq_mask = omap_gpio_mask_irq,
>>       .irq_unmask = omap_gpio_unmask_irq,
>> +    .irq_disable = omap_gpio_disable_irq,
>> +    .irq_enable = omap_gpio_enable_irq,
>>       .irq_set_type = omap_gpio_irq_type,
>>       .irq_bus_lock = omap_gpio_irq_bus_lock,
>>       .irq_bus_sync_unlock = gpio_irq_bus_sync_unlock,

[PATCH RESEND 2/2] serial: 8250: omap: Move pm_runtime_get_sync

[Judith Mendez]

Currently in omap_8250_shutdown, the dma->rx_running
flag is set to zero in omap_8250_rx_dma_flush. Next
pm_runtime_get_sync is called, which is a runtime
resume call stack which can re-set the flag. When the
call omap_8250_shutdown returns, the flag is expected
to be UN-SET, but this is not the case. This is causing
issues the next time UART is re-opened and omap_8250_rx_dma
is called. Fix by moving pm_runtime_get_sync before the
omap_8250_rx_dma_flush.

Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Judith Mendez <jm@ti.com>
---
 drivers/tty/serial/8250/8250_omap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 88b58f44e4e9..0dd68bdbfbcf 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -776,12 +776,12 @@ static void omap_8250_shutdown(struct uart_port *port)
 	struct uart_8250_port *up = up_to_u8250p(port);
 	struct omap8250_priv *priv = port->private_data;
 
+	pm_runtime_get_sync(port->dev);
+
 	flush_work(&priv->qos_work);
 	if (up->dma)
 		omap_8250_rx_dma_flush(up);
 
-	pm_runtime_get_sync(port->dev);
-
 	serial_out(up, UART_OMAP_WER, 0);
 	if (priv->habit & UART_HAS_EFR2)
 		serial_out(up, UART_OMAP_EFR2, 0x0);
-- 
2.47.0

Re: [PATCH RESEND 2/2] serial: 8250: omap: Move pm_runtime_get_sync

[Kevin Hilman]

Judith Mendez <jm@ti.com> writes:

> Currently in omap_8250_shutdown, the dma->rx_running
> flag is set to zero in omap_8250_rx_dma_flush. Next
> pm_runtime_get_sync is called, which is a runtime
> resume call stack which can re-set the flag. When the
> call omap_8250_shutdown returns, the flag is expected
> to be UN-SET, but this is not the case. This is causing
> issues the next time UART is re-opened and omap_8250_rx_dma
> is called. Fix by moving pm_runtime_get_sync before the
> omap_8250_rx_dma_flush.
>
> Signed-off-by: Bin Liu <b-liu@ti.com>
> Signed-off-by: Judith Mendez <jm@ti.com>

Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Kevin Hilman <khilman@baylibre.com>

Gave this a quick boot test on am335x-boneblack and am57xx-beagle-x15.

I realize that doesn't really test the DMA paths involved here, but at
least it doesn't break basic boot to serial console, and the change
looks coorect.

Thanks for sending a fix for this.

Kevin

Re: [PATCH RESEND 2/2] serial: 8250: omap: Move pm_runtime_get_sync

[Greg KH]

On Fri, Oct 11, 2024 at 12:33:56PM -0500, Judith Mendez wrote:
> Currently in omap_8250_shutdown, the dma->rx_running
> flag is set to zero in omap_8250_rx_dma_flush. Next
> pm_runtime_get_sync is called, which is a runtime
> resume call stack which can re-set the flag. When the
> call omap_8250_shutdown returns, the flag is expected
> to be UN-SET, but this is not the case. This is causing
> issues the next time UART is re-opened and omap_8250_rx_dma
> is called. Fix by moving pm_runtime_get_sync before the
> omap_8250_rx_dma_flush.

You can go to 72 columns :)

> Signed-off-by: Bin Liu <b-liu@ti.com>
> Signed-off-by: Judith Mendez <jm@ti.com>

Wait, who wrote this, Bin?  If so, there needs to be a "From:" line
saying so.

What commit id does this fix?  Do you want it backported to older
kernels?  Why mix two different subsystems in the same patch series, who
is supposed to take it?

thanks,

greg k-h

Re: [PATCH RESEND 2/2] serial: 8250: omap: Move pm_runtime_get_sync

[Judith Mendez]

Hi Greg,

On 10/12/24 3:03 AM, Greg KH wrote:
> On Fri, Oct 11, 2024 at 12:33:56PM -0500, Judith Mendez wrote:
>> Currently in omap_8250_shutdown, the dma->rx_running
>> flag is set to zero in omap_8250_rx_dma_flush. Next
>> pm_runtime_get_sync is called, which is a runtime
>> resume call stack which can re-set the flag. When the
>> call omap_8250_shutdown returns, the flag is expected
>> to be UN-SET, but this is not the case. This is causing
>> issues the next time UART is re-opened and omap_8250_rx_dma
>> is called. Fix by moving pm_runtime_get_sync before the
>> omap_8250_rx_dma_flush.
> 
> You can go to 72 columns :)

ok, will fix, thanks!

> 
>> Signed-off-by: Bin Liu <b-liu@ti.com>
>> Signed-off-by: Judith Mendez <jm@ti.com>
> 
> Wait, who wrote this, Bin?  If so, there needs to be a "From:" line
> saying so.

I did not realize I could create a patch for someone, apologies, I
will be sending v3 with correct "From:".

> 
> What commit id does this fix?  Do you want it backported to older
> kernels?  Why mix two different subsystems in the same patch series, who
> is supposed to take it?


I suppose it should be backported to older kernels so I will add back
the fixes tag.

Apologies for sending two different subsystems in one series, I thought
describing as "misc" would be good enough to mix the two, but I can
separate the patches and respin. Thanks.

~ Judith


> 
> thanks,
> 
> greg k-h

Re: [PATCH RESEND 2/2] serial: 8250: omap: Move pm_runtime_get_sync

[Andreas Kemnade]

Am Fri, 11 Oct 2024 12:33:56 -0500
schrieb Judith Mendez <jm@ti.com>:

> Currently in omap_8250_shutdown, the dma->rx_running
> flag is set to zero in omap_8250_rx_dma_flush. Next
> pm_runtime_get_sync is called, which is a runtime
> resume call stack which can re-set the flag. When the
> call omap_8250_shutdown returns, the flag is expected
> to be UN-SET, but this is not the case. This is causing
> issues the next time UART is re-opened and omap_8250_rx_dma
> is called. Fix by moving pm_runtime_get_sync before the
> omap_8250_rx_dma_flush.
> 
> Signed-off-by: Bin Liu <b-liu@ti.com>
> Signed-off-by: Judith Mendez <jm@ti.com>

Is this a theorectical problem or some real practical problem?
So you are running a system with runtime pm enabled on serial
console.
How did you come across this issue?
I could run the serial console/getty with runtime pm autosuspend enabled
without issues all the years.

Regards,
Andreas

Re: [PATCH RESEND 2/2] serial: 8250: omap: Move pm_runtime_get_sync

[Andreas Kemnade]

Am Sun, 13 Oct 2024 21:52:05 -0500
schrieb Bin Liu <binmlist@gmail.com>:

> Hi,
> 
> Somehow this email wasn’t cc’d to my company email account
> b-liu@ti.com, so I am replying from my personal email which
> subscribed to the mailing list, and sorry if the formatting is wrong
> since I am writing this response on my phone. 
> 
> On Oct 12, 2024, at 7:27 AM, Andreas Kemnade <andreas@kemnade.info>
> wrote:
> > 
> > Am Fri, 11 Oct 2024 12:33:56 -0500
> > schrieb Judith Mendez <jm@ti.com>:
> > 
> > Currently in omap_8250_shutdown, the dma->rx_running
> >> flag is set to zero in omap_8250_rx_dma_flush. Next
> >> pm_runtime_get_sync is called, which is a runtime
> >> resume call stack which can re-set the flag. When the
> >> call omap_8250_shutdown returns, the flag is expected
> >> to be UN-SET, but this is not the case. This is causing
> >> issues the next time UART is re-opened and omap_8250_rx_dma
> >> is called. Fix by moving pm_runtime_get_sync before the
> >> omap_8250_rx_dma_flush.
> >> 
> >> Signed-off-by: Bin Liu <b-liu@ti.com>
> >> Signed-off-by: Judith Mendez <jm@ti.com>
> >> 
> > Is this a theorectical problem or some real practical problem?
> > So you are running a system with runtime pm enabled on serial
> > console.
> > How did you come across this issue?
> > I could run the serial console/getty with runtime pm autosuspend
> > enabled without issues all the years.
> > 
> Yes this is a real issue reported on AM335x. Please see the report
> linked below.
> 
> PROCESSOR-SDK-AM335X: Possible bug in 8250_omap UART driver -
> Processors forum - Processors - TI E2E support forums e2e.ti.com
> 
> 
Thanks for information, so it looks like material for backporting.
Maybe add the link in the description and add the cc stable and 
add back the fixes tag.

Regards,
Andreas

Re: [PATCH RESEND 0/2] Misc OMAP GPIO/UART fixes

[Kevin Hilman]

Judith Mendez <jm@ti.com> writes:

> This patch series carries some miscellaneous
> OMAP driver fixes for GPIO and UART drivers.
>
> For GPIO, add gpio_enable and gpio_disable calls
> to gpio-omap which fixes an issue where if there
> is an irq storm, serial console is unresponsive.
>
> For UART, move pm_runtime_get_sync since the
> current order of omap_8250_rx_dma_flush and
> pm_runtime_get_sync calls are set in a way that
> when omap_8250_shutdown returns, dma->rx_running
> is set and this causes issues next time the UART
> is re-opened.

Could you summarize which OMAP platforms this was tested on?

Thanks,

Kevin