drivers/pmdomain/ti/ti_sci_pm_domains.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
For TI K3 SoCs with IO daisy-chaining using pinctrl wakeup state, avoid
sending wakeup constraints to the PM co-processor. This allows the SoC to
enter deeper low power states while still maintaining wakeup capability
for peripherals using IO daisy-chain wakeup via pinctrl wakeup state,
similar to the existing wake IRQ mechanism added in commit b06bc47279919
("pmdomain: ti_sci: handle wake IRQs for IO daisy chain wakeups").
Detect the pinctrl wakeup state in the suspend path, and if it exists,
skip sending the constraint.
Signed-off-by: Kendall Willis <k-willis@ti.com>
---
Implementation
--------------
This patch is intended to be implemented along with the following
series. This patch has no dependencies on any of the other series:
1. "pmdomain: ti_sci: Handle wakeup constraint if device has pinctrl
wakeup state": (this patch) skips setting constraints for wakeup
sources that use pinctrl state 'wakeup'.
2. "serial: 8250: omap: Add wakeup support": Implements wakeup from
the UARTs for TI K3 SoCs
https://github.com/kwillis01/linux/tree/b4/uart-daisy-chain-8250-omap
3. "arm64: dts: ti: k3-am62: Support Main UART wakeup": Implements the
functionality to wakeup the system from the Main UART
https://github.com/kwillis01/linux/tree/b4/uart-daisy-chain-dts
Testing
-------
Tested on a AM62P SK EVM board with all series and dependencies
implemented. Suspend/resume verified with the Main UART wakeup source
by entering a keypress on the console.
This github branch has all the necessary patches to test the series
using linux-next:
https://github.com/kwillis01/linux/tree/uart-daisy-chain
Version History
---------------
Changes from v1 to v2:
- Reworded commit message to be concise and to reference commit
b06bc47279919
v1: https://lore.kernel.org/all/20250904211607.3725897-1-k-willis@ti.com/
---
drivers/pmdomain/ti/ti_sci_pm_domains.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/pmdomain/ti/ti_sci_pm_domains.c b/drivers/pmdomain/ti/ti_sci_pm_domains.c
index 82df7e44250bb64f9c4a2108b5e97bd782a5976d..884905fd0686c1b94aba68c03da038e577428adf 100644
--- a/drivers/pmdomain/ti/ti_sci_pm_domains.c
+++ b/drivers/pmdomain/ti/ti_sci_pm_domains.c
@@ -10,6 +10,7 @@
#include <linux/err.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/pm_domain.h>
#include <linux/pm_qos.h>
@@ -84,9 +85,24 @@ static inline void ti_sci_pd_set_wkup_constraint(struct device *dev)
struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
struct ti_sci_pm_domain *pd = genpd_to_ti_sci_pd(genpd);
const struct ti_sci_handle *ti_sci = pd->parent->ti_sci;
+ struct pinctrl *pinctrl = devm_pinctrl_get(dev);
+ struct pinctrl_state *pinctrl_state_wakeup;
int ret;
if (device_may_wakeup(dev)) {
+ /*
+ * If device can wakeup using pinctrl wakeup state,
+ * we do not want to set a constraint
+ */
+ if (!IS_ERR_OR_NULL(pinctrl)) {
+ pinctrl_state_wakeup = pinctrl_lookup_state(pinctrl, "wakeup");
+ if (!IS_ERR_OR_NULL(pinctrl_state_wakeup)) {
+ dev_dbg(dev, "%s: has wake pinctrl wakeup state, not setting " \
+ "constraints\n", __func__);
+ return;
+ }
+ }
+
/*
* If device can wakeup using IO daisy chain wakeups,
* we do not want to set a constraint.
---
base-commit: 5f540c4aade9f1d58fb7b9490b4b7d5214ec9746
change-id: 20250910-uart-daisy-chain-pmdomain-b83b2db2c3cc
Best regards,
--
Kendall Willis <k-willis@ti.com>
On Wed, 10 Sept 2025 at 23:16, Kendall Willis <k-willis@ti.com> wrote:
>
> For TI K3 SoCs with IO daisy-chaining using pinctrl wakeup state, avoid
> sending wakeup constraints to the PM co-processor. This allows the SoC to
> enter deeper low power states while still maintaining wakeup capability
> for peripherals using IO daisy-chain wakeup via pinctrl wakeup state,
> similar to the existing wake IRQ mechanism added in commit b06bc47279919
> ("pmdomain: ti_sci: handle wake IRQs for IO daisy chain wakeups").
>
> Detect the pinctrl wakeup state in the suspend path, and if it exists,
> skip sending the constraint.
>
> Signed-off-by: Kendall Willis <k-willis@ti.com>
> ---
> Implementation
> --------------
> This patch is intended to be implemented along with the following
> series. This patch has no dependencies on any of the other series:
>
> 1. "pmdomain: ti_sci: Handle wakeup constraint if device has pinctrl
> wakeup state": (this patch) skips setting constraints for wakeup
> sources that use pinctrl state 'wakeup'.
>
> 2. "serial: 8250: omap: Add wakeup support": Implements wakeup from
> the UARTs for TI K3 SoCs
> https://github.com/kwillis01/linux/tree/b4/uart-daisy-chain-8250-omap
>
> 3. "arm64: dts: ti: k3-am62: Support Main UART wakeup": Implements the
> functionality to wakeup the system from the Main UART
> https://github.com/kwillis01/linux/tree/b4/uart-daisy-chain-dts
>
> Testing
> -------
> Tested on a AM62P SK EVM board with all series and dependencies
> implemented. Suspend/resume verified with the Main UART wakeup source
> by entering a keypress on the console.
>
> This github branch has all the necessary patches to test the series
> using linux-next:
> https://github.com/kwillis01/linux/tree/uart-daisy-chain
>
> Version History
> ---------------
> Changes from v1 to v2:
> - Reworded commit message to be concise and to reference commit
> b06bc47279919
>
> v1: https://lore.kernel.org/all/20250904211607.3725897-1-k-willis@ti.com/
> ---
> drivers/pmdomain/ti/ti_sci_pm_domains.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/pmdomain/ti/ti_sci_pm_domains.c b/drivers/pmdomain/ti/ti_sci_pm_domains.c
> index 82df7e44250bb64f9c4a2108b5e97bd782a5976d..884905fd0686c1b94aba68c03da038e577428adf 100644
> --- a/drivers/pmdomain/ti/ti_sci_pm_domains.c
> +++ b/drivers/pmdomain/ti/ti_sci_pm_domains.c
> @@ -10,6 +10,7 @@
> #include <linux/err.h>
> #include <linux/module.h>
> #include <linux/of.h>
> +#include <linux/pinctrl/consumer.h>
> #include <linux/platform_device.h>
> #include <linux/pm_domain.h>
> #include <linux/pm_qos.h>
> @@ -84,9 +85,24 @@ static inline void ti_sci_pd_set_wkup_constraint(struct device *dev)
> struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
> struct ti_sci_pm_domain *pd = genpd_to_ti_sci_pd(genpd);
> const struct ti_sci_handle *ti_sci = pd->parent->ti_sci;
> + struct pinctrl *pinctrl = devm_pinctrl_get(dev);
> + struct pinctrl_state *pinctrl_state_wakeup;
> int ret;
>
> if (device_may_wakeup(dev)) {
> + /*
> + * If device can wakeup using pinctrl wakeup state,
> + * we do not want to set a constraint
> + */
> + if (!IS_ERR_OR_NULL(pinctrl)) {
> + pinctrl_state_wakeup = pinctrl_lookup_state(pinctrl, "wakeup");
> + if (!IS_ERR_OR_NULL(pinctrl_state_wakeup)) {
> + dev_dbg(dev, "%s: has wake pinctrl wakeup state, not setting " \
> + "constraints\n", __func__);
> + return;
> + }
> + }
Relying on the above condition and the wakeirq check that was added in
b06bc47279919, seems fragile and doesn't really seem like the best
approach to me.
I would rather think that we should rely on the driver for the
consumer device to successfully have completed its parts, by enabling
the out-band system-wakeup IRQ. In other words, make the consumer
driver to call device_set_out_band_wakeup() and then use
device_out_band_wakeup() instead of the pinctrl+wakeirq check above,
to understand if QoS constraints shall be sent to the FW or not.
> +
> /*
> * If device can wakeup using IO daisy chain wakeups,
> * we do not want to set a constraint.
>
> ---
> base-commit: 5f540c4aade9f1d58fb7b9490b4b7d5214ec9746
> change-id: 20250910-uart-daisy-chain-pmdomain-b83b2db2c3cc
>
> Best regards,
> --
> Kendall Willis <k-willis@ti.com>
>
Kind regards
Uffe
On 10/21/25 07:22, Ulf Hansson wrote:
> On Wed, 10 Sept 2025 at 23:16, Kendall Willis <k-willis@ti.com> wrote:
>>
>> For TI K3 SoCs with IO daisy-chaining using pinctrl wakeup state, avoid
>> sending wakeup constraints to the PM co-processor. This allows the SoC to
>> enter deeper low power states while still maintaining wakeup capability
>> for peripherals using IO daisy-chain wakeup via pinctrl wakeup state,
>> similar to the existing wake IRQ mechanism added in commit b06bc47279919
>> ("pmdomain: ti_sci: handle wake IRQs for IO daisy chain wakeups").
>>
>> Detect the pinctrl wakeup state in the suspend path, and if it exists,
>> skip sending the constraint.
>>
>> Signed-off-by: Kendall Willis <k-willis@ti.com>
>> ---
>> Implementation
>> --------------
>> This patch is intended to be implemented along with the following
>> series. This patch has no dependencies on any of the other series:
>>
>> 1. "pmdomain: ti_sci: Handle wakeup constraint if device has pinctrl
>> wakeup state": (this patch) skips setting constraints for wakeup
>> sources that use pinctrl state 'wakeup'.
>>
>> 2. "serial: 8250: omap: Add wakeup support": Implements wakeup from
>> the UARTs for TI K3 SoCs
>> https://github.com/kwillis01/linux/tree/b4/uart-daisy-chain-8250-omap
>>
>> 3. "arm64: dts: ti: k3-am62: Support Main UART wakeup": Implements the
>> functionality to wakeup the system from the Main UART
>> https://github.com/kwillis01/linux/tree/b4/uart-daisy-chain-dts
>>
>> Testing
>> -------
>> Tested on a AM62P SK EVM board with all series and dependencies
>> implemented. Suspend/resume verified with the Main UART wakeup source
>> by entering a keypress on the console.
>>
>> This github branch has all the necessary patches to test the series
>> using linux-next:
>> https://github.com/kwillis01/linux/tree/uart-daisy-chain
>>
>> Version History
>> ---------------
>> Changes from v1 to v2:
>> - Reworded commit message to be concise and to reference commit
>> b06bc47279919
>>
>> v1: https://lore.kernel.org/all/20250904211607.3725897-1-k-willis@ti.com/
>> ---
>> drivers/pmdomain/ti/ti_sci_pm_domains.c | 16 ++++++++++++++++
>> 1 file changed, 16 insertions(+)
>>
>> diff --git a/drivers/pmdomain/ti/ti_sci_pm_domains.c b/drivers/pmdomain/ti/ti_sci_pm_domains.c
>> index 82df7e44250bb64f9c4a2108b5e97bd782a5976d..884905fd0686c1b94aba68c03da038e577428adf 100644
>> --- a/drivers/pmdomain/ti/ti_sci_pm_domains.c
>> +++ b/drivers/pmdomain/ti/ti_sci_pm_domains.c
>> @@ -10,6 +10,7 @@
>> #include <linux/err.h>
>> #include <linux/module.h>
>> #include <linux/of.h>
>> +#include <linux/pinctrl/consumer.h>
>> #include <linux/platform_device.h>
>> #include <linux/pm_domain.h>
>> #include <linux/pm_qos.h>
>> @@ -84,9 +85,24 @@ static inline void ti_sci_pd_set_wkup_constraint(struct device *dev)
>> struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
>> struct ti_sci_pm_domain *pd = genpd_to_ti_sci_pd(genpd);
>> const struct ti_sci_handle *ti_sci = pd->parent->ti_sci;
>> + struct pinctrl *pinctrl = devm_pinctrl_get(dev);
>> + struct pinctrl_state *pinctrl_state_wakeup;
>> int ret;
>>
>> if (device_may_wakeup(dev)) {
>> + /*
>> + * If device can wakeup using pinctrl wakeup state,
>> + * we do not want to set a constraint
>> + */
>> + if (!IS_ERR_OR_NULL(pinctrl)) {
>> + pinctrl_state_wakeup = pinctrl_lookup_state(pinctrl, "wakeup");
>> + if (!IS_ERR_OR_NULL(pinctrl_state_wakeup)) {
>> + dev_dbg(dev, "%s: has wake pinctrl wakeup state, not setting " \
>> + "constraints\n", __func__);
>> + return;
>> + }
>> + }
>
> Relying on the above condition and the wakeirq check that was added in
> b06bc47279919, seems fragile and doesn't really seem like the best
> approach to me.
>
> I would rather think that we should rely on the driver for the
> consumer device to successfully have completed its parts, by enabling
> the out-band system-wakeup IRQ. In other words, make the consumer
> driver to call device_set_out_band_wakeup() and then use
> device_out_band_wakeup() instead of the pinctrl+wakeirq check above,
> to understand if QoS constraints shall be sent to the FW or not.
That makes sense, I will add this to the next version for the patches.
Thanks for the suggestion!
Apologies for the late reply, I somehow missed this.
Best,
Kendall Willis
>
>> +
>> /*
>> * If device can wakeup using IO daisy chain wakeups,
>> * we do not want to set a constraint.
>>
>> ---
>> base-commit: 5f540c4aade9f1d58fb7b9490b4b7d5214ec9746
>> change-id: 20250910-uart-daisy-chain-pmdomain-b83b2db2c3cc
>>
>> Best regards,
>> --
>> Kendall Willis <k-willis@ti.com>
>>
>
> Kind regards
> Uffe
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