[RFC,v14,3/5] PCI / PM: Add support for the PCIe WAKE# signal for OF

Message ID 20230208111645.3863534-4-mmaddireddy@nvidia.com
State New
Headers
Series Add DT based PCIe wake support in PCI core driver |

Commit Message

Manikanta Maddireddy Feb. 8, 2023, 11:16 a.m. UTC
  From: Jeffy Chen <jeffy.chen@rock-chips.com>

Add of_pci_setup_wake_irq() to parse the PCIe WAKE# interrupt from the
device tree and set the wake irq. Add of_pci_teardown_wake_irq() to clear
the wake irq.

Call of_pci_setup_wake_irq() in pci_device_probe() to setup PCIe WAKE#
interrupt during PCIe Endpoint enumeration.

Enable or disable PCIe WAKE# interrupt in platform_pci_set_wakeup().

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
---

Changes in v14:
pci_platform_pm_ops structure is removed in latest kernel, so dropped
pci-of driver. Instead, enable wake in platform_pci_set_wakeup().

Changes in v13:
Fix compiler error reported by kbuild test robot <fengguang.wu@intel.com>

Changes in v12:
Enable the wake irq in noirq stage to avoid possible irq storm.

Changes in v11:
Only support 1-per-device PCIe WAKE# pin as suggested.

Changes in v10:
Use device_set_wakeup_capable() instead of device_set_wakeup_enable(),
since dedicated wakeirq will be lost in device_set_wakeup_enable(false).

Changes in v9:
Fix check error in .cleanup().
Move dedicated wakeirq setup to setup() callback and use
device_set_wakeup_enable() to enable/disable.

Changes in v8:
Add pci-of.c and use platform_pm_ops to handle the PCIe WAKE# signal.

Changes in v7:
Move PCIE_WAKE handling into pci core.

Changes in v6:
Fix device_init_wake error handling, and add some comments.

Changes in v5:
Rebase.

Changes in v3:
Fix error handling.

Changes in v2:
Use dev_pm_set_dedicated_wake_irq.

 drivers/pci/of.c         | 49 ++++++++++++++++++++++++++++++++++++++++
 drivers/pci/pci-driver.c | 10 ++++++++
 drivers/pci/pci.c        |  7 ++++++
 drivers/pci/pci.h        |  8 +++++++
 4 files changed, 74 insertions(+)
  

Comments

Thierry Reding Feb. 8, 2023, 11:50 a.m. UTC | #1
On Wed, Feb 08, 2023 at 04:46:43PM +0530, Manikanta Maddireddy wrote:
> From: Jeffy Chen <jeffy.chen@rock-chips.com>
> 
> Add of_pci_setup_wake_irq() to parse the PCIe WAKE# interrupt from the
> device tree and set the wake irq. Add of_pci_teardown_wake_irq() to clear
> the wake irq.
> 
> Call of_pci_setup_wake_irq() in pci_device_probe() to setup PCIe WAKE#
> interrupt during PCIe Endpoint enumeration.
> 
> Enable or disable PCIe WAKE# interrupt in platform_pci_set_wakeup().
> 
> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
> ---
> 
> Changes in v14:
> pci_platform_pm_ops structure is removed in latest kernel, so dropped
> pci-of driver. Instead, enable wake in platform_pci_set_wakeup().
> 
> Changes in v13:
> Fix compiler error reported by kbuild test robot <fengguang.wu@intel.com>
> 
> Changes in v12:
> Enable the wake irq in noirq stage to avoid possible irq storm.
> 
> Changes in v11:
> Only support 1-per-device PCIe WAKE# pin as suggested.
> 
> Changes in v10:
> Use device_set_wakeup_capable() instead of device_set_wakeup_enable(),
> since dedicated wakeirq will be lost in device_set_wakeup_enable(false).
> 
> Changes in v9:
> Fix check error in .cleanup().
> Move dedicated wakeirq setup to setup() callback and use
> device_set_wakeup_enable() to enable/disable.
> 
> Changes in v8:
> Add pci-of.c and use platform_pm_ops to handle the PCIe WAKE# signal.
> 
> Changes in v7:
> Move PCIE_WAKE handling into pci core.
> 
> Changes in v6:
> Fix device_init_wake error handling, and add some comments.
> 
> Changes in v5:
> Rebase.
> 
> Changes in v3:
> Fix error handling.
> 
> Changes in v2:
> Use dev_pm_set_dedicated_wake_irq.
> 
>  drivers/pci/of.c         | 49 ++++++++++++++++++++++++++++++++++++++++
>  drivers/pci/pci-driver.c | 10 ++++++++
>  drivers/pci/pci.c        |  7 ++++++
>  drivers/pci/pci.h        |  8 +++++++
>  4 files changed, 74 insertions(+)
> 
> diff --git a/drivers/pci/of.c b/drivers/pci/of.c
> index ff897c40ed71..1c348e63f175 100644
> --- a/drivers/pci/of.c
> +++ b/drivers/pci/of.c
> @@ -13,6 +13,7 @@
>  #include <linux/of_irq.h>
>  #include <linux/of_address.h>
>  #include <linux/of_pci.h>
> +#include <linux/pm_wakeirq.h>
>  #include "pci.h"
>  
>  #ifdef CONFIG_PCI
> @@ -705,3 +706,51 @@ u32 of_pci_get_slot_power_limit(struct device_node *node,
>  	return slot_power_limit_mw;
>  }
>  EXPORT_SYMBOL_GPL(of_pci_get_slot_power_limit);
> +
> +int of_pci_setup_wake_irq(struct pci_dev *pdev)
> +{
> +	struct pci_dev *ppdev;

Perhaps "parent" since that's what it is referring to? ppdev is a bit
vague.

> +	struct device_node *dn;
> +	int ret, irq;
> +
> +	/* Get the pci_dev of our parent. Hopefully it's a port. */
> +	ppdev = pdev->bus->self;
> +	/* Nope, it's a host bridge. */
> +	if (!ppdev)
> +		return 0;
> +
> +	dn = pci_device_to_OF_node(ppdev);
> +	if (!dn)
> +		return 0;
> +
> +	irq = of_irq_get_byname(dn, "wakeup");
> +	if (irq == -EPROBE_DEFER) {
> +		return irq;
> +	} else if (irq < 0) {
> +		/* Ignore other errors, since a missing wakeup is non-fatal. */
> +		dev_info(&pdev->dev, "cannot get wakeup interrupt: %d\n", irq);

dev_dbg() maybe? As it is this would add an annoying info message for
basically every PCI controller on every DT-based board out there.

Thierry
  
Manikanta Maddireddy Feb. 8, 2023, 12:19 p.m. UTC | #2
On 2/8/2023 5:20 PM, Thierry Reding wrote:
> On Wed, Feb 08, 2023 at 04:46:43PM +0530, Manikanta Maddireddy wrote:
>> From: Jeffy Chen <jeffy.chen@rock-chips.com>
>>
>> Add of_pci_setup_wake_irq() to parse the PCIe WAKE# interrupt from the
>> device tree and set the wake irq. Add of_pci_teardown_wake_irq() to clear
>> the wake irq.
>>
>> Call of_pci_setup_wake_irq() in pci_device_probe() to setup PCIe WAKE#
>> interrupt during PCIe Endpoint enumeration.
>>
>> Enable or disable PCIe WAKE# interrupt in platform_pci_set_wakeup().
>>
>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>> Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
>> ---
>>
>> Changes in v14:
>> pci_platform_pm_ops structure is removed in latest kernel, so dropped
>> pci-of driver. Instead, enable wake in platform_pci_set_wakeup().
>>
>> Changes in v13:
>> Fix compiler error reported by kbuild test robot <fengguang.wu@intel.com>
>>
>> Changes in v12:
>> Enable the wake irq in noirq stage to avoid possible irq storm.
>>
>> Changes in v11:
>> Only support 1-per-device PCIe WAKE# pin as suggested.
>>
>> Changes in v10:
>> Use device_set_wakeup_capable() instead of device_set_wakeup_enable(),
>> since dedicated wakeirq will be lost in device_set_wakeup_enable(false).
>>
>> Changes in v9:
>> Fix check error in .cleanup().
>> Move dedicated wakeirq setup to setup() callback and use
>> device_set_wakeup_enable() to enable/disable.
>>
>> Changes in v8:
>> Add pci-of.c and use platform_pm_ops to handle the PCIe WAKE# signal.
>>
>> Changes in v7:
>> Move PCIE_WAKE handling into pci core.
>>
>> Changes in v6:
>> Fix device_init_wake error handling, and add some comments.
>>
>> Changes in v5:
>> Rebase.
>>
>> Changes in v3:
>> Fix error handling.
>>
>> Changes in v2:
>> Use dev_pm_set_dedicated_wake_irq.
>>
>>   drivers/pci/of.c         | 49 ++++++++++++++++++++++++++++++++++++++++
>>   drivers/pci/pci-driver.c | 10 ++++++++
>>   drivers/pci/pci.c        |  7 ++++++
>>   drivers/pci/pci.h        |  8 +++++++
>>   4 files changed, 74 insertions(+)
>>
>> diff --git a/drivers/pci/of.c b/drivers/pci/of.c
>> index ff897c40ed71..1c348e63f175 100644
>> --- a/drivers/pci/of.c
>> +++ b/drivers/pci/of.c
>> @@ -13,6 +13,7 @@
>>   #include <linux/of_irq.h>
>>   #include <linux/of_address.h>
>>   #include <linux/of_pci.h>
>> +#include <linux/pm_wakeirq.h>
>>   #include "pci.h"
>>   
>>   #ifdef CONFIG_PCI
>> @@ -705,3 +706,51 @@ u32 of_pci_get_slot_power_limit(struct device_node *node,
>>   	return slot_power_limit_mw;
>>   }
>>   EXPORT_SYMBOL_GPL(of_pci_get_slot_power_limit);
>> +
>> +int of_pci_setup_wake_irq(struct pci_dev *pdev)
>> +{
>> +	struct pci_dev *ppdev;
> Perhaps "parent" since that's what it is referring to? ppdev is a bit
> vague.
ppdev is already used in of_irq_parse_pci(), I think it mean parent pci_dev.
I see that parent is mostly used for pci_bus parent. Let me know if it 
is fine
to leave it as ppdev or need to rename it.
>
>> +	struct device_node *dn;
>> +	int ret, irq;
>> +
>> +	/* Get the pci_dev of our parent. Hopefully it's a port. */
>> +	ppdev = pdev->bus->self;
>> +	/* Nope, it's a host bridge. */
>> +	if (!ppdev)
>> +		return 0;
>> +
>> +	dn = pci_device_to_OF_node(ppdev);
>> +	if (!dn)
>> +		return 0;
>> +
>> +	irq = of_irq_get_byname(dn, "wakeup");
>> +	if (irq == -EPROBE_DEFER) {
>> +		return irq;
>> +	} else if (irq < 0) {
>> +		/* Ignore other errors, since a missing wakeup is non-fatal. */
>> +		dev_info(&pdev->dev, "cannot get wakeup interrupt: %d\n", irq);
> dev_dbg() maybe? As it is this would add an annoying info message for
> basically every PCI controller on every DT-based board out there.
>
> Thierry
Ack. I will wait for few days for other review this series before 
sending new patch set.

Manikanta
  

Patch

diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index ff897c40ed71..1c348e63f175 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -13,6 +13,7 @@ 
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
 #include <linux/of_pci.h>
+#include <linux/pm_wakeirq.h>
 #include "pci.h"
 
 #ifdef CONFIG_PCI
@@ -705,3 +706,51 @@  u32 of_pci_get_slot_power_limit(struct device_node *node,
 	return slot_power_limit_mw;
 }
 EXPORT_SYMBOL_GPL(of_pci_get_slot_power_limit);
+
+int of_pci_setup_wake_irq(struct pci_dev *pdev)
+{
+	struct pci_dev *ppdev;
+	struct device_node *dn;
+	int ret, irq;
+
+	/* Get the pci_dev of our parent. Hopefully it's a port. */
+	ppdev = pdev->bus->self;
+	/* Nope, it's a host bridge. */
+	if (!ppdev)
+		return 0;
+
+	dn = pci_device_to_OF_node(ppdev);
+	if (!dn)
+		return 0;
+
+	irq = of_irq_get_byname(dn, "wakeup");
+	if (irq == -EPROBE_DEFER) {
+		return irq;
+	} else if (irq < 0) {
+		/* Ignore other errors, since a missing wakeup is non-fatal. */
+		dev_info(&pdev->dev, "cannot get wakeup interrupt: %d\n", irq);
+		return 0;
+	}
+
+	device_init_wakeup(&pdev->dev, true);
+
+	ret = dev_pm_set_dedicated_wake_irq(&pdev->dev, irq);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to set wake IRQ: %d\n", ret);
+		device_init_wakeup(&pdev->dev, false);
+		return ret;
+	}
+
+	/* Start out disabled to avoid irq storm */
+	dev_pm_disable_wake_irq(&pdev->dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_pci_setup_wake_irq);
+
+void of_pci_teardown_wake_irq(struct pci_dev *pdev)
+{
+	dev_pm_clear_wake_irq(&pdev->dev);
+	device_init_wakeup(&pdev->dev, false);
+}
+EXPORT_SYMBOL_GPL(of_pci_teardown_wake_irq);
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index d934c27491c4..fca966137fac 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -14,6 +14,7 @@ 
 #include <linux/sched.h>
 #include <linux/sched/isolation.h>
 #include <linux/cpu.h>
+#include <linux/of_pci.h>
 #include <linux/pm_runtime.h>
 #include <linux/suspend.h>
 #include <linux/kexec.h>
@@ -456,10 +457,17 @@  static int pci_device_probe(struct device *dev)
 	if (error < 0)
 		return error;
 
+	error = of_pci_setup_wake_irq(pci_dev);
+	if (error < 0) {
+		pcibios_free_irq(pci_dev);
+		return error;
+	}
+
 	pci_dev_get(pci_dev);
 	error = __pci_device_probe(drv, pci_dev);
 	if (error) {
 		pcibios_free_irq(pci_dev);
+		of_pci_teardown_wake_irq(pci_dev);
 		pci_dev_put(pci_dev);
 	}
 
@@ -471,6 +479,8 @@  static void pci_device_remove(struct device *dev)
 	struct pci_dev *pci_dev = to_pci_dev(dev);
 	struct pci_driver *drv = pci_dev->driver;
 
+	of_pci_teardown_wake_irq(pci_dev);
+
 	if (drv->remove) {
 		pm_runtime_get_sync(dev);
 		drv->remove(pci_dev);
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index fba95486caaf..332a0b98b6c3 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -27,6 +27,7 @@ 
 #include <linux/interrupt.h>
 #include <linux/device.h>
 #include <linux/pm_runtime.h>
+#include <linux/pm_wakeirq.h>
 #include <linux/pci_hotplug.h>
 #include <linux/vmalloc.h>
 #include <asm/dma.h>
@@ -1052,6 +1053,12 @@  static inline int platform_pci_set_wakeup(struct pci_dev *dev, bool enable)
 	if (pci_use_mid_pm())
 		return PCI_POWER_ERROR;
 
+	/* Enable or disable wakeirq if set via device tree. */
+	if (enable)
+		dev_pm_enable_wake_irq(&dev->dev);
+	else
+		dev_pm_disable_wake_irq(&dev->dev);
+
 	return acpi_pci_wakeup(dev, enable);
 }
 
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 9ed3b5550043..83a2af148631 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -631,6 +631,8 @@  int of_pci_get_max_link_speed(struct device_node *node);
 u32 of_pci_get_slot_power_limit(struct device_node *node,
 				u8 *slot_power_limit_value,
 				u8 *slot_power_limit_scale);
+int of_pci_setup_wake_irq(struct pci_dev *pdev);
+void of_pci_teardown_wake_irq(struct pci_dev *pdev);
 void pci_set_of_node(struct pci_dev *dev);
 void pci_release_of_node(struct pci_dev *dev);
 void pci_set_bus_of_node(struct pci_bus *bus);
@@ -669,6 +671,12 @@  of_pci_get_slot_power_limit(struct device_node *node,
 	return 0;
 }
 
+static inline int of_pci_setup_wake_irq(struct pci_dev *pdev)
+{
+	return 0;
+}
+
+static inline void of_pci_teardown_wake_irq(struct pci_dev *pdev) { }
 static inline void pci_set_of_node(struct pci_dev *dev) { }
 static inline void pci_release_of_node(struct pci_dev *dev) { }
 static inline void pci_set_bus_of_node(struct pci_bus *bus) { }