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* [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM
@ 2019-08-31 20:10 Heiner Kallweit
  2019-08-31 20:15 ` [PATCH v5 1/4] PCI/ASPM: add L1 sub-state support to pci_disable_link_state Heiner Kallweit
                   ` (4 more replies)
  0 siblings, 5 replies; 8+ messages in thread
From: Heiner Kallweit @ 2019-08-31 20:10 UTC (permalink / raw)
  To: Frederick Lawler, Bjorn Helgaas, Greg KH, Rajat Jain; +Cc: linux-pci

Background of this extension is a problem with the r8169 network driver.
Several combinations of board chipsets and network chip versions have
problems if ASPM is enabled, therefore we have to disable ASPM per
default. However especially on notebooks ASPM can provide significant
power-saving, therefore we want to give users the option to enable
ASPM. With the new sysfs attributes users can control which ASPM
link-states are disabled.

Note: Series depends on series "PCI: Make pcie_downstream_port()
available outside of access.c" from Mika Westerberg that is still
sitting in the PCI inbox. 
Alternatively I could prepare a version w/o this dependency, but
then Mika's series would need to be changed.

v2:
- use a dedicated sysfs attribute per link state
- allow separate control of ASPM and PCI PM L1 sub-states

v3:
- patch 3: statically allocate the attribute group
- patch 3: replace snprintf with printf
- add patch 4

v4:
- patch 3: add call to sysfs_update_group because is_visible callback
           returns false always at file creation time
- patch 3: simplify code a little

v5:
- rebased to latest pci/next

Heiner Kallweit (4):
  PCI/ASPM: add L1 sub-state support to pci_disable_link_state
  PCI/ASPM: allow to re-enable Clock PM
  PCI/ASPM: add sysfs attributes for controlling ASPM link states
  PCI/ASPM: remove Kconfig option PCIEASPM_DEBUG and related code

 Documentation/ABI/testing/sysfs-bus-pci |  13 ++
 drivers/pci/pci-sysfs.c                 |  10 +-
 drivers/pci/pci.h                       |  12 +-
 drivers/pci/pcie/Kconfig                |   7 -
 drivers/pci/pcie/aspm.c                 | 236 ++++++++++++++++--------
 include/linux/pci.h                     |  10 +-
 6 files changed, 195 insertions(+), 93 deletions(-)

-- 
2.23.0


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH v5 1/4] PCI/ASPM: add L1 sub-state support to pci_disable_link_state
  2019-08-31 20:10 [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM Heiner Kallweit
@ 2019-08-31 20:15 ` Heiner Kallweit
  2019-08-31 20:16 ` [PATCH v5 2/4] PCI/ASPM: allow to re-enable Clock PM Heiner Kallweit
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 8+ messages in thread
From: Heiner Kallweit @ 2019-08-31 20:15 UTC (permalink / raw)
  To: Frederick Lawler, Bjorn Helgaas, Greg KH, Rajat Jain; +Cc: linux-pci

Add support for disabling states L1.1 and L1.2 to
pci_disable_link_state. Allow separate control of
ASPM and PCI PM L1 sub-states.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- allow separate control of ASPM and PCI PM L1 sub-states
v5:
- rebased to latest pci/next
---
 drivers/pci/pcie/aspm.c | 11 ++++++++++-
 include/linux/pci.h     | 10 +++++++---
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index ad6259ec5..6de7a597a 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -1094,7 +1094,16 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
 	if (state & PCIE_LINK_STATE_L0S)
 		link->aspm_disable |= ASPM_STATE_L0S;
 	if (state & PCIE_LINK_STATE_L1)
-		link->aspm_disable |= ASPM_STATE_L1;
+		/* sub-states require L1 */
+		link->aspm_disable |= ASPM_STATE_L1 | ASPM_STATE_L1SS;
+	if (state & PCIE_LINK_STATE_L1_1)
+		link->aspm_disable |= ASPM_STATE_L1_1;
+	if (state & PCIE_LINK_STATE_L1_2)
+		link->aspm_disable |= ASPM_STATE_L1_2;
+	if (state & PCIE_LINK_STATE_L1_1_PCIPM)
+		link->aspm_disable |= ASPM_STATE_L1_1_PCIPM;
+	if (state & PCIE_LINK_STATE_L1_2_PCIPM)
+		link->aspm_disable |= ASPM_STATE_L1_2_PCIPM;
 	pcie_config_aspm_link(link, policy_to_aspm_state(link));
 
 	if (state & PCIE_LINK_STATE_CLKPM) {
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 67303262f..054345eed 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1553,9 +1553,13 @@ extern bool pcie_ports_native;
 #define pcie_ports_native	false
 #endif
 
-#define PCIE_LINK_STATE_L0S	1
-#define PCIE_LINK_STATE_L1	2
-#define PCIE_LINK_STATE_CLKPM	4
+#define PCIE_LINK_STATE_L0S		BIT(0)
+#define PCIE_LINK_STATE_L1		BIT(1)
+#define PCIE_LINK_STATE_CLKPM		BIT(2)
+#define PCIE_LINK_STATE_L1_1		BIT(3)
+#define PCIE_LINK_STATE_L1_2		BIT(4)
+#define PCIE_LINK_STATE_L1_1_PCIPM	BIT(5)
+#define PCIE_LINK_STATE_L1_2_PCIPM	BIT(6)
 
 #ifdef CONFIG_PCIEASPM
 int pci_disable_link_state(struct pci_dev *pdev, int state);
-- 
2.23.0



^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH v5 2/4] PCI/ASPM: allow to re-enable Clock PM
  2019-08-31 20:10 [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM Heiner Kallweit
  2019-08-31 20:15 ` [PATCH v5 1/4] PCI/ASPM: add L1 sub-state support to pci_disable_link_state Heiner Kallweit
@ 2019-08-31 20:16 ` Heiner Kallweit
  2019-08-31 20:18 ` [PATCH v5 4/4] PCI/ASPM: remove Kconfig option PCIEASPM_DEBUG and related code Heiner Kallweit
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 8+ messages in thread
From: Heiner Kallweit @ 2019-08-31 20:16 UTC (permalink / raw)
  To: Frederick Lawler, Bjorn Helgaas, Greg KH, Rajat Jain; +Cc: linux-pci

So far Clock PM can't be re-enabled once it has been disabled with
a call to pci_disable_link_state(). Reason is that clkpm_capable
is reset. Change this by adding a clkpm_disable field similar to
aspm_disable.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/pci/pcie/aspm.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 6de7a597a..f044ae4d1 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -64,6 +64,7 @@ struct pcie_link_state {
 	u32 clkpm_capable:1;		/* Clock PM capable? */
 	u32 clkpm_enabled:1;		/* Current Clock PM state */
 	u32 clkpm_default:1;		/* Default Clock PM state by BIOS */
+	u32 clkpm_disable:1;		/* Clock PM disabled */
 
 	/* Exit latencies */
 	struct aspm_latency latency_up;	/* Upstream direction exit latency */
@@ -161,8 +162,11 @@ static void pcie_set_clkpm_nocheck(struct pcie_link_state *link, int enable)
 
 static void pcie_set_clkpm(struct pcie_link_state *link, int enable)
 {
-	/* Don't enable Clock PM if the link is not Clock PM capable */
-	if (!link->clkpm_capable)
+	/*
+	 * Don't enable Clock PM if the link is not Clock PM capable
+	 * or Clock PM is disabled
+	 */
+	if (!link->clkpm_capable || link->clkpm_disable)
 		enable = 0;
 	/* Need nothing if the specified equals to current state */
 	if (link->clkpm_enabled == enable)
@@ -192,7 +196,8 @@ static void pcie_clkpm_cap_init(struct pcie_link_state *link, int blacklist)
 	}
 	link->clkpm_enabled = enabled;
 	link->clkpm_default = enabled;
-	link->clkpm_capable = (blacklist) ? 0 : capable;
+	link->clkpm_capable = capable;
+	link->clkpm_disable = blacklist ? 1 : 0;
 }
 
 static bool pcie_retrain_link(struct pcie_link_state *link)
@@ -1106,10 +1111,9 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
 		link->aspm_disable |= ASPM_STATE_L1_2_PCIPM;
 	pcie_config_aspm_link(link, policy_to_aspm_state(link));
 
-	if (state & PCIE_LINK_STATE_CLKPM) {
-		link->clkpm_capable = 0;
-		pcie_set_clkpm(link, 0);
-	}
+	if (state & PCIE_LINK_STATE_CLKPM)
+		link->clkpm_disable = 1;
+	pcie_set_clkpm(link, policy_to_clkpm_state(link));
 	mutex_unlock(&aspm_lock);
 	if (sem)
 		up_read(&pci_bus_sem);
-- 
2.23.0



^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH v5 4/4] PCI/ASPM: remove Kconfig option PCIEASPM_DEBUG and related code
  2019-08-31 20:10 [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM Heiner Kallweit
  2019-08-31 20:15 ` [PATCH v5 1/4] PCI/ASPM: add L1 sub-state support to pci_disable_link_state Heiner Kallweit
  2019-08-31 20:16 ` [PATCH v5 2/4] PCI/ASPM: allow to re-enable Clock PM Heiner Kallweit
@ 2019-08-31 20:18 ` Heiner Kallweit
  2019-09-07 20:34   ` Bjorn Helgaas
  2019-08-31 20:20 ` [PATCH v5 3/4] PCI/ASPM: add sysfs attributes for controlling ASPM link states Heiner Kallweit
  2019-09-07 16:58 ` [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM Bjorn Helgaas
  4 siblings, 1 reply; 8+ messages in thread
From: Heiner Kallweit @ 2019-08-31 20:18 UTC (permalink / raw)
  To: Frederick Lawler, Bjorn Helgaas, Greg KH, Rajat Jain; +Cc: linux-pci

Now that we have sysfs attributes for enabling/disabling the individual
ASPM link states, this debug code isn't needed any longer.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v5:
- rebased to latest pci/next
---
 drivers/pci/pci-sysfs.c  |   3 --
 drivers/pci/pci.h        |   8 ---
 drivers/pci/pcie/Kconfig |   7 ---
 drivers/pci/pcie/aspm.c  | 105 ---------------------------------------
 4 files changed, 123 deletions(-)

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 687240f55..acba3aff0 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -1314,7 +1314,6 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev)
 	int retval;
 
 	pcie_vpd_create_sysfs_dev_files(dev);
-	pcie_aspm_create_sysfs_dev_files(dev);
 #ifdef CONFIG_PCIEASPM
 	/* update visibility of attributes in this group */
 	sysfs_update_group(&dev->dev.kobj, &aspm_ctrl_attr_group);
@@ -1328,7 +1327,6 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev)
 	return 0;
 
 error:
-	pcie_aspm_remove_sysfs_dev_files(dev);
 	pcie_vpd_remove_sysfs_dev_files(dev);
 	return retval;
 }
@@ -1404,7 +1402,6 @@ int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev)
 static void pci_remove_capabilities_sysfs(struct pci_dev *dev)
 {
 	pcie_vpd_remove_sysfs_dev_files(dev);
-	pcie_aspm_remove_sysfs_dev_files(dev);
 	if (dev->reset_fn) {
 		device_remove_file(&dev->dev, &dev_attr_reset);
 		dev->reset_fn = 0;
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 9dc3e3673..b3d3da257 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -533,14 +533,6 @@ static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) { }
 static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { }
 #endif
 
-#ifdef CONFIG_PCIEASPM_DEBUG
-void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev);
-void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev);
-#else
-static inline void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev) { }
-static inline void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev) { }
-#endif
-
 #ifdef CONFIG_PCIE_ECRC
 void pcie_set_ecrc_checking(struct pci_dev *dev);
 void pcie_ecrc_get_policy(char *str);
diff --git a/drivers/pci/pcie/Kconfig b/drivers/pci/pcie/Kconfig
index 362eb8cfa..a2e862d4e 100644
--- a/drivers/pci/pcie/Kconfig
+++ b/drivers/pci/pcie/Kconfig
@@ -79,13 +79,6 @@ config PCIEASPM
 
 	  When in doubt, say Y.
 
-config PCIEASPM_DEBUG
-	bool "Debug PCI Express ASPM"
-	depends on PCIEASPM
-	help
-	  This enables PCI Express ASPM debug support. It will add per-device
-	  interface to control ASPM.
-
 choice
 	prompt "Default ASPM policy"
 	default PCIEASPM_DEFAULT
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index ce3425125..67a142251 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -1182,111 +1182,6 @@ static int pcie_aspm_get_policy(char *buffer, const struct kernel_param *kp)
 module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy,
 	NULL, 0644);
 
-#ifdef CONFIG_PCIEASPM_DEBUG
-static ssize_t link_state_show(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct pci_dev *pci_device = to_pci_dev(dev);
-	struct pcie_link_state *link_state = pci_device->link_state;
-
-	return sprintf(buf, "%d\n", link_state->aspm_enabled);
-}
-
-static ssize_t link_state_store(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t n)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-	struct pcie_link_state *link, *root = pdev->link_state->root;
-	u32 state;
-
-	if (aspm_disabled)
-		return -EPERM;
-
-	if (kstrtouint(buf, 10, &state))
-		return -EINVAL;
-	if ((state & ~ASPM_STATE_ALL) != 0)
-		return -EINVAL;
-
-	down_read(&pci_bus_sem);
-	mutex_lock(&aspm_lock);
-	list_for_each_entry(link, &link_list, sibling) {
-		if (link->root != root)
-			continue;
-		pcie_config_aspm_link(link, state);
-	}
-	mutex_unlock(&aspm_lock);
-	up_read(&pci_bus_sem);
-	return n;
-}
-
-static ssize_t clk_ctl_show(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct pci_dev *pci_device = to_pci_dev(dev);
-	struct pcie_link_state *link_state = pci_device->link_state;
-
-	return sprintf(buf, "%d\n", link_state->clkpm_enabled);
-}
-
-static ssize_t clk_ctl_store(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t n)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-	bool state;
-
-	if (strtobool(buf, &state))
-		return -EINVAL;
-
-	down_read(&pci_bus_sem);
-	mutex_lock(&aspm_lock);
-	pcie_set_clkpm_nocheck(pdev->link_state, state);
-	mutex_unlock(&aspm_lock);
-	up_read(&pci_bus_sem);
-
-	return n;
-}
-
-static DEVICE_ATTR_RW(link_state);
-static DEVICE_ATTR_RW(clk_ctl);
-
-static char power_group[] = "power";
-void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev)
-{
-	struct pcie_link_state *link_state = pdev->link_state;
-
-	if (!link_state)
-		return;
-
-	if (link_state->aspm_support)
-		sysfs_add_file_to_group(&pdev->dev.kobj,
-			&dev_attr_link_state.attr, power_group);
-	if (link_state->clkpm_capable)
-		sysfs_add_file_to_group(&pdev->dev.kobj,
-			&dev_attr_clk_ctl.attr, power_group);
-}
-
-void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev)
-{
-	struct pcie_link_state *link_state = pdev->link_state;
-
-	if (!link_state)
-		return;
-
-	if (link_state->aspm_support)
-		sysfs_remove_file_from_group(&pdev->dev.kobj,
-			&dev_attr_link_state.attr, power_group);
-	if (link_state->clkpm_capable)
-		sysfs_remove_file_from_group(&pdev->dev.kobj,
-			&dev_attr_clk_ctl.attr, power_group);
-}
-#endif
-
 static struct pcie_link_state *aspm_get_parent_link(struct pci_dev *pdev)
 {
 	struct pci_dev *parent = pdev->bus->self;
-- 
2.23.0



^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH v5 3/4] PCI/ASPM: add sysfs attributes for controlling ASPM link states
  2019-08-31 20:10 [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM Heiner Kallweit
                   ` (2 preceding siblings ...)
  2019-08-31 20:18 ` [PATCH v5 4/4] PCI/ASPM: remove Kconfig option PCIEASPM_DEBUG and related code Heiner Kallweit
@ 2019-08-31 20:20 ` Heiner Kallweit
  2019-09-07 20:32   ` Bjorn Helgaas
  2019-09-07 16:58 ` [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM Bjorn Helgaas
  4 siblings, 1 reply; 8+ messages in thread
From: Heiner Kallweit @ 2019-08-31 20:20 UTC (permalink / raw)
  To: Frederick Lawler, Bjorn Helgaas, Greg KH, Rajat Jain; +Cc: linux-pci

Background of this extension is a problem with the r8169 network driver.
Several combinations of board chipsets and network chip versions have
problems if ASPM is enabled, therefore we have to disable ASPM per default.
However especially on notebooks ASPM can provide significant power-saving,
therefore we want to give users the option to enable ASPM. With the new
sysfs attributes users can control which ASPM link-states are
enabled/disabled.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
v2:
- use a dedicated sysfs attribute per link state
- allow separate control of ASPM and PCI PM L1 sub-states
v3:
- statically allocate the attribute group
- replace snprintf with printf
- base on top of "PCI: Make pcie_downstream_port() available outside of access.c"
v4:
- add call to sysfs_update_group because is_visible callback returns false
  always at file creation time
- simplify code a little
v5:
- rebased to latest pci/next
---
 Documentation/ABI/testing/sysfs-bus-pci |  13 ++
 drivers/pci/pci-sysfs.c                 |   7 +
 drivers/pci/pci.h                       |   4 +
 drivers/pci/pcie/aspm.c                 | 184 ++++++++++++++++++++++++
 4 files changed, 208 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index 8bfee557e..49249a165 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -347,3 +347,16 @@ Description:
 		If the device has any Peer-to-Peer memory registered, this
 	        file contains a '1' if the memory has been published for
 		use outside the driver that owns the device.
+
+What		/sys/bus/pci/devices/.../aspm/aspm_l0s
+What		/sys/bus/pci/devices/.../aspm/aspm_l1
+What		/sys/bus/pci/devices/.../aspm/aspm_l1_1
+What		/sys/bus/pci/devices/.../aspm/aspm_l1_2
+What		/sys/bus/pci/devices/.../aspm/aspm_l1_1_pcipm
+What		/sys/bus/pci/devices/.../aspm/aspm_l1_2_pcipm
+What		/sys/bus/pci/devices/.../aspm/aspm_clkpm
+date:		August 2019
+Contact:	Heiner Kallweit <hkallweit1@gmail.com>
+Description:	If ASPM is supported for an endpoint, then these files
+		can be used to disable or enable the individual
+		power management states.
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 868e35109..687240f55 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -1315,6 +1315,10 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev)
 
 	pcie_vpd_create_sysfs_dev_files(dev);
 	pcie_aspm_create_sysfs_dev_files(dev);
+#ifdef CONFIG_PCIEASPM
+	/* update visibility of attributes in this group */
+	sysfs_update_group(&dev->dev.kobj, &aspm_ctrl_attr_group);
+#endif
 
 	if (dev->reset_fn) {
 		retval = device_create_file(&dev->dev, &dev_attr_reset);
@@ -1571,6 +1575,9 @@ static const struct attribute_group *pci_dev_attr_groups[] = {
 	&pcie_dev_attr_group,
 #ifdef CONFIG_PCIEAER
 	&aer_stats_attr_group,
+#endif
+#ifdef CONFIG_PCIEASPM
+	&aspm_ctrl_attr_group,
 #endif
 	NULL,
 };
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 44b80186d..9dc3e3673 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -659,4 +659,8 @@ static inline int pci_acpi_program_hp_params(struct pci_dev *dev)
 }
 #endif
 
+#ifdef CONFIG_PCIEASPM
+extern const struct attribute_group aspm_ctrl_attr_group;
+#endif
+
 #endif /* DRIVERS_PCI_H */
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index f044ae4d1..ce3425125 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -1287,6 +1287,190 @@ void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev)
 }
 #endif
 
+static struct pcie_link_state *aspm_get_parent_link(struct pci_dev *pdev)
+{
+	struct pci_dev *parent = pdev->bus->self;
+
+	if (pcie_downstream_port(pdev))
+		parent = pdev;
+
+	return parent ? parent->link_state : NULL;
+}
+
+static bool pcie_check_valid_aspm_endpoint(struct pci_dev *pdev)
+{
+	struct pcie_link_state *link;
+
+	if (!pci_is_pcie(pdev) || pci_pcie_type(pdev) != PCI_EXP_TYPE_ENDPOINT)
+		return false;
+
+	link = aspm_get_parent_link(pdev);
+
+	return link && link->aspm_capable;
+}
+
+static ssize_t aspm_attr_show_common(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf, int state)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct pcie_link_state *link;
+	int val;
+
+	link = aspm_get_parent_link(pdev);
+	if (!link)
+		return -EOPNOTSUPP;
+
+	mutex_lock(&aspm_lock);
+	val = !!(link->aspm_enabled & state);
+	mutex_unlock(&aspm_lock);
+
+	return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t aspm_attr_store_common(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf, size_t len, int state)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct pcie_link_state *link;
+	bool state_enable;
+
+	if (aspm_disabled)
+		return -EPERM;
+
+	link = aspm_get_parent_link(pdev);
+	if (!link)
+		return -EOPNOTSUPP;
+
+	if (!(link->aspm_capable & state))
+		return -EOPNOTSUPP;
+
+	if (strtobool(buf, &state_enable) < 0)
+		return -EINVAL;
+
+	down_read(&pci_bus_sem);
+	mutex_lock(&aspm_lock);
+
+	if (state_enable) {
+		link->aspm_disable &= ~state;
+		/* need to enable L1 for sub-states */
+		if (state & ASPM_STATE_L1SS)
+			link->aspm_disable &= ~ASPM_STATE_L1;
+	} else {
+		link->aspm_disable |= state;
+	}
+
+	pcie_config_aspm_link(link, policy_to_aspm_state(link));
+
+	mutex_unlock(&aspm_lock);
+	up_read(&pci_bus_sem);
+
+	return len;
+}
+
+#define ASPM_ATTR(_f, _s)						\
+static ssize_t aspm_##_f##_show(struct device *dev,			\
+			struct device_attribute *attr, char *buf)	\
+{ return aspm_attr_show_common(dev, attr, buf, ASPM_STATE_##_s); }	\
+									\
+static ssize_t aspm_##_f##_store(struct device *dev,			\
+				 struct device_attribute *attr,		\
+				 const char *buf, size_t len)		\
+{ return aspm_attr_store_common(dev, attr, buf, len, ASPM_STATE_##_s); }
+
+ASPM_ATTR(l0s, L0S)
+ASPM_ATTR(l1, L1)
+ASPM_ATTR(l1_1, L1_1)
+ASPM_ATTR(l1_2, L1_2)
+ASPM_ATTR(l1_1_pcipm, L1_1_PCIPM)
+ASPM_ATTR(l1_2_pcipm, L1_2_PCIPM)
+
+static ssize_t aspm_clkpm_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct pcie_link_state *link;
+	int val;
+
+	link = aspm_get_parent_link(pdev);
+	if (!link)
+		return -EOPNOTSUPP;
+
+	mutex_lock(&aspm_lock);
+	val = link->clkpm_enabled;
+	mutex_unlock(&aspm_lock);
+
+	return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t aspm_clkpm_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t len)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct pcie_link_state *link;
+	bool state_enable;
+
+	if (aspm_disabled)
+		return -EPERM;
+
+	link = aspm_get_parent_link(pdev);
+	if (!link)
+		return -EOPNOTSUPP;
+
+	if (!link->clkpm_capable)
+		return -EOPNOTSUPP;
+
+	if (strtobool(buf, &state_enable) < 0)
+		return -EINVAL;
+
+	down_read(&pci_bus_sem);
+	mutex_lock(&aspm_lock);
+
+	link->clkpm_disable = !state_enable;
+	pcie_set_clkpm(link, policy_to_clkpm_state(link));
+
+	mutex_unlock(&aspm_lock);
+	up_read(&pci_bus_sem);
+
+	return len;
+}
+
+static DEVICE_ATTR_RW(aspm_l0s);
+static DEVICE_ATTR_RW(aspm_l1);
+static DEVICE_ATTR_RW(aspm_l1_1);
+static DEVICE_ATTR_RW(aspm_l1_2);
+static DEVICE_ATTR_RW(aspm_l1_1_pcipm);
+static DEVICE_ATTR_RW(aspm_l1_2_pcipm);
+static DEVICE_ATTR_RW(aspm_clkpm);
+
+static struct attribute *aspm_ctrl_attrs[] = {
+	&dev_attr_aspm_l0s.attr,
+	&dev_attr_aspm_l1.attr,
+	&dev_attr_aspm_l1_1.attr,
+	&dev_attr_aspm_l1_2.attr,
+	&dev_attr_aspm_l1_1_pcipm.attr,
+	&dev_attr_aspm_l1_2_pcipm.attr,
+	&dev_attr_aspm_clkpm.attr,
+	NULL
+};
+
+static umode_t aspm_ctrl_attrs_are_visible(struct kobject *kobj,
+					   struct attribute *a, int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	return pcie_check_valid_aspm_endpoint(pdev) ? a->mode : 0;
+}
+
+const struct attribute_group aspm_ctrl_attr_group = {
+	.name = "aspm",
+	.attrs = aspm_ctrl_attrs,
+	.is_visible = aspm_ctrl_attrs_are_visible,
+};
+
 static int __init pcie_aspm_disable(char *str)
 {
 	if (!strcmp(str, "off")) {
-- 
2.23.0




^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM
  2019-08-31 20:10 [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM Heiner Kallweit
                   ` (3 preceding siblings ...)
  2019-08-31 20:20 ` [PATCH v5 3/4] PCI/ASPM: add sysfs attributes for controlling ASPM link states Heiner Kallweit
@ 2019-09-07 16:58 ` Bjorn Helgaas
  4 siblings, 0 replies; 8+ messages in thread
From: Bjorn Helgaas @ 2019-09-07 16:58 UTC (permalink / raw)
  To: Heiner Kallweit; +Cc: Frederick Lawler, Greg KH, Rajat Jain, linux-pci

On Sat, Aug 31, 2019 at 10:10:00PM +0200, Heiner Kallweit wrote:
> Background of this extension is a problem with the r8169 network driver.
> Several combinations of board chipsets and network chip versions have
> problems if ASPM is enabled, therefore we have to disable ASPM per
> default. However especially on notebooks ASPM can provide significant
> power-saving, therefore we want to give users the option to enable
> ASPM. With the new sysfs attributes users can control which ASPM
> link-states are disabled.
> 
> Note: Series depends on series "PCI: Make pcie_downstream_port()
> available outside of access.c" from Mika Westerberg that is still
> sitting in the PCI inbox. 
> Alternatively I could prepare a version w/o this dependency, but
> then Mika's series would need to be changed.

It would be better for me if your series applied directly to my
"master" branch (v5.3-rc1).

This v5 depends on Mika's series (which I've since applied), and also
on Krzysztof's linux/pci-aspm.h cleanup.  But neither of them is
essential for your series, and I put them on different topic branches
since Mika's isn't ASPM-related while Krzysztof's is.  That makes it
messy to merge them and apply yours on top (it could certainly be
*done*, but I just avoid that sort git complication).

Both of those *are* cleanups that are relevant to your series, but
it's easier if your series applies directly to my "master" branch, and
I can take care of the merge issues when I merge all the branches
together.

> v2:
> - use a dedicated sysfs attribute per link state
> - allow separate control of ASPM and PCI PM L1 sub-states
> 
> v3:
> - patch 3: statically allocate the attribute group
> - patch 3: replace snprintf with printf
> - add patch 4
> 
> v4:
> - patch 3: add call to sysfs_update_group because is_visible callback
>            returns false always at file creation time
> - patch 3: simplify code a little
> 
> v5:
> - rebased to latest pci/next
> 
> Heiner Kallweit (4):
>   PCI/ASPM: add L1 sub-state support to pci_disable_link_state
>   PCI/ASPM: allow to re-enable Clock PM
>   PCI/ASPM: add sysfs attributes for controlling ASPM link states
>   PCI/ASPM: remove Kconfig option PCIEASPM_DEBUG and related code

Nit here, please capitalize the first word of each subject, e.g.,

  PCI/ASPM: Add L1 PM Substate support to pci_disable_link_state()

and "L1 PM Substate" to match the spec usage, and I like "()" after
function names as a hint.  Also applies to other commit logs.

>  Documentation/ABI/testing/sysfs-bus-pci |  13 ++
>  drivers/pci/pci-sysfs.c                 |  10 +-
>  drivers/pci/pci.h                       |  12 +-
>  drivers/pci/pcie/Kconfig                |   7 -
>  drivers/pci/pcie/aspm.c                 | 236 ++++++++++++++++--------
>  include/linux/pci.h                     |  10 +-
>  6 files changed, 195 insertions(+), 93 deletions(-)
> 
> -- 
> 2.23.0
> 

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v5 3/4] PCI/ASPM: add sysfs attributes for controlling ASPM link states
  2019-08-31 20:20 ` [PATCH v5 3/4] PCI/ASPM: add sysfs attributes for controlling ASPM link states Heiner Kallweit
@ 2019-09-07 20:32   ` Bjorn Helgaas
  0 siblings, 0 replies; 8+ messages in thread
From: Bjorn Helgaas @ 2019-09-07 20:32 UTC (permalink / raw)
  To: Heiner Kallweit; +Cc: Frederick Lawler, Greg KH, Rajat Jain, linux-pci

On Sat, Aug 31, 2019 at 10:20:47PM +0200, Heiner Kallweit wrote:
> Background of this extension is a problem with the r8169 network driver.
> Several combinations of board chipsets and network chip versions have
> problems if ASPM is enabled, therefore we have to disable ASPM per default.
> However especially on notebooks ASPM can provide significant power-saving,
> therefore we want to give users the option to enable ASPM. With the new
> sysfs attributes users can control which ASPM link-states are
> enabled/disabled.
> 
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
> v2:
> - use a dedicated sysfs attribute per link state
> - allow separate control of ASPM and PCI PM L1 sub-states
> v3:
> - statically allocate the attribute group
> - replace snprintf with printf
> - base on top of "PCI: Make pcie_downstream_port() available outside of access.c"
> v4:
> - add call to sysfs_update_group because is_visible callback returns false
>   always at file creation time
> - simplify code a little
> v5:
> - rebased to latest pci/next
> ---
>  Documentation/ABI/testing/sysfs-bus-pci |  13 ++
>  drivers/pci/pci-sysfs.c                 |   7 +
>  drivers/pci/pci.h                       |   4 +
>  drivers/pci/pcie/aspm.c                 | 184 ++++++++++++++++++++++++
>  4 files changed, 208 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
> index 8bfee557e..49249a165 100644
> --- a/Documentation/ABI/testing/sysfs-bus-pci
> +++ b/Documentation/ABI/testing/sysfs-bus-pci
> @@ -347,3 +347,16 @@ Description:
>  		If the device has any Peer-to-Peer memory registered, this
>  	        file contains a '1' if the memory has been published for
>  		use outside the driver that owns the device.
> +
> +What		/sys/bus/pci/devices/.../aspm/aspm_l0s
> +What		/sys/bus/pci/devices/.../aspm/aspm_l1
> +What		/sys/bus/pci/devices/.../aspm/aspm_l1_1
> +What		/sys/bus/pci/devices/.../aspm/aspm_l1_2
> +What		/sys/bus/pci/devices/.../aspm/aspm_l1_1_pcipm
> +What		/sys/bus/pci/devices/.../aspm/aspm_l1_2_pcipm
> +What		/sys/bus/pci/devices/.../aspm/aspm_clkpm
> +date:		August 2019

Other entries use "What:" and "Date:" (add colon and capitalize).

There are no examples in *this* file, but in
Documentation/ABI/testing/sysfs-bus-pci-drivers-ehci_hcd,
the "What:" is not repeated for each file in the group.

> +Contact:	Heiner Kallweit <hkallweit1@gmail.com>
> +Description:	If ASPM is supported for an endpoint, then these files
> +		can be used to disable or enable the individual
> +		power management states.

Please mention the specific details here, e.g., "write 1 to enable, 0
to disable".

> diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
> index 868e35109..687240f55 100644
> --- a/drivers/pci/pci-sysfs.c
> +++ b/drivers/pci/pci-sysfs.c
> @@ -1315,6 +1315,10 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev)
>  
>  	pcie_vpd_create_sysfs_dev_files(dev);
>  	pcie_aspm_create_sysfs_dev_files(dev);
> +#ifdef CONFIG_PCIEASPM
> +	/* update visibility of attributes in this group */
> +	sysfs_update_group(&dev->dev.kobj, &aspm_ctrl_attr_group);
> +#endif

Isn't there a way to do this in drivers/pci/pcie/aspm.c somehow,
without using sysfs_update_group()?  There are only three callers of
it in the tree, and I'd be surprised if ASPM is unique enough to have
to be the fourth.

>  	if (dev->reset_fn) {
>  		retval = device_create_file(&dev->dev, &dev_attr_reset);
> @@ -1571,6 +1575,9 @@ static const struct attribute_group *pci_dev_attr_groups[] = {
>  	&pcie_dev_attr_group,
>  #ifdef CONFIG_PCIEAER
>  	&aer_stats_attr_group,
> +#endif
> +#ifdef CONFIG_PCIEASPM
> +	&aspm_ctrl_attr_group,
>  #endif
>  	NULL,
>  };
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index 44b80186d..9dc3e3673 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -659,4 +659,8 @@ static inline int pci_acpi_program_hp_params(struct pci_dev *dev)
>  }
>  #endif
>  
> +#ifdef CONFIG_PCIEASPM
> +extern const struct attribute_group aspm_ctrl_attr_group;
> +#endif
> +
>  #endif /* DRIVERS_PCI_H */
> diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
> index f044ae4d1..ce3425125 100644
> --- a/drivers/pci/pcie/aspm.c
> +++ b/drivers/pci/pcie/aspm.c
> @@ -1287,6 +1287,190 @@ void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev)
>  }
>  #endif
>  
> +static struct pcie_link_state *aspm_get_parent_link(struct pci_dev *pdev)

I know the ASPM code is pretty confused, but I don't think "parent
link" really makes sense.  "Parent" implies a parent/child
relationship, but a link doesn't have a parent or a child; it only has
an upstream end and a downstream end.

Anyway, any given PCIe device has either zero or one link associated
with it, so something like "aspm_get_link()" would be unambiguous all
by itself.

> +{
> +	struct pci_dev *parent = pdev->bus->self;
> +
> +	if (pcie_downstream_port(pdev))
> +		parent = pdev;
> +
> +	return parent ? parent->link_state : NULL;
> +}
> +
> +static bool pcie_check_valid_aspm_endpoint(struct pci_dev *pdev)

Maybe "pcie_is_aspm_dev()" or similar?  I think we may want to include
more than just endpoints (see below).  "Check" in function names is a
pet peeve of mine because it doesn't tell us whether it's a pure
function (as this is) or it has side effects, and it doesn't give a
hint about what the sense of the return value is.

> +{
> +	struct pcie_link_state *link;
> +
> +	if (!pci_is_pcie(pdev) || pci_pcie_type(pdev) != PCI_EXP_TYPE_ENDPOINT)

Do you intend to exclude other Upstream Ports like Legacy Endpoints,
Upstream Switch Ports, and PCIe-to-PCI/PCI-X Bridges?  They also have
a link leading to them, so we might want them to have knobs as well.
Or if we don't want the knobs, a comment about why not would be
useful.

> +		return false;
> +
> +	link = aspm_get_parent_link(pdev);
> +
> +	return link && link->aspm_capable;
> +}
> +
> +static ssize_t aspm_attr_show_common(struct device *dev,
> +				     struct device_attribute *attr,
> +				     char *buf, int state)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev);
> +	struct pcie_link_state *link;
> +	int val;
> +
> +	link = aspm_get_parent_link(pdev);
> +	if (!link)
> +		return -EOPNOTSUPP;
> +
> +	mutex_lock(&aspm_lock);
> +	val = !!(link->aspm_enabled & state);

I'm not a huge fan of "!!".  There are several uses in this file, but
I think this:

  enabled = link->aspm_enabled & state;
  ...
  return sprintf(buf, "%d\n", enabled ? 1 : 0);

is clearer.

> +	mutex_unlock(&aspm_lock);
> +
> +	return sprintf(buf, "%d\n", val);
> +}
> +
> +static ssize_t aspm_attr_store_common(struct device *dev,
> +				      struct device_attribute *attr,
> +				      const char *buf, size_t len, int state)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev);
> +	struct pcie_link_state *link;
> +	bool state_enable;
> +
> +	if (aspm_disabled)
> +		return -EPERM;
> +
> +	link = aspm_get_parent_link(pdev);
> +	if (!link)
> +		return -EOPNOTSUPP;
> +
> +	if (!(link->aspm_capable & state))
> +		return -EOPNOTSUPP;
> +
> +	if (strtobool(buf, &state_enable) < 0)
> +		return -EINVAL;
> +
> +	down_read(&pci_bus_sem);
> +	mutex_lock(&aspm_lock);
> +
> +	if (state_enable) {
> +		link->aspm_disable &= ~state;
> +		/* need to enable L1 for sub-states */
> +		if (state & ASPM_STATE_L1SS)
> +			link->aspm_disable &= ~ASPM_STATE_L1;
> +	} else {
> +		link->aspm_disable |= state;
> +	}
> +
> +	pcie_config_aspm_link(link, policy_to_aspm_state(link));
> +
> +	mutex_unlock(&aspm_lock);
> +	up_read(&pci_bus_sem);
> +
> +	return len;
> +}
> +
> +#define ASPM_ATTR(_f, _s)						\
> +static ssize_t aspm_##_f##_show(struct device *dev,			\
> +			struct device_attribute *attr, char *buf)	\
> +{ return aspm_attr_show_common(dev, attr, buf, ASPM_STATE_##_s); }	\
> +									\
> +static ssize_t aspm_##_f##_store(struct device *dev,			\
> +				 struct device_attribute *attr,		\
> +				 const char *buf, size_t len)		\
> +{ return aspm_attr_store_common(dev, attr, buf, len, ASPM_STATE_##_s); }
> +
> +ASPM_ATTR(l0s, L0S)
> +ASPM_ATTR(l1, L1)
> +ASPM_ATTR(l1_1, L1_1)
> +ASPM_ATTR(l1_2, L1_2)
> +ASPM_ATTR(l1_1_pcipm, L1_1_PCIPM)
> +ASPM_ATTR(l1_2_pcipm, L1_2_PCIPM)
> +
> +static ssize_t aspm_clkpm_show(struct device *dev,
> +			       struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev);
> +	struct pcie_link_state *link;
> +	int val;
> +
> +	link = aspm_get_parent_link(pdev);
> +	if (!link)
> +		return -EOPNOTSUPP;
> +
> +	mutex_lock(&aspm_lock);
> +	val = link->clkpm_enabled;
> +	mutex_unlock(&aspm_lock);
> +
> +	return sprintf(buf, "%d\n", val);
> +}
> +
> +static ssize_t aspm_clkpm_store(struct device *dev,
> +				struct device_attribute *attr,
> +				const char *buf, size_t len)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev);
> +	struct pcie_link_state *link;
> +	bool state_enable;
> +
> +	if (aspm_disabled)
> +		return -EPERM;
> +
> +	link = aspm_get_parent_link(pdev);
> +	if (!link)
> +		return -EOPNOTSUPP;
> +
> +	if (!link->clkpm_capable)
> +		return -EOPNOTSUPP;
> +
> +	if (strtobool(buf, &state_enable) < 0)
> +		return -EINVAL;
> +
> +	down_read(&pci_bus_sem);
> +	mutex_lock(&aspm_lock);
> +
> +	link->clkpm_disable = !state_enable;
> +	pcie_set_clkpm(link, policy_to_clkpm_state(link));
> +
> +	mutex_unlock(&aspm_lock);
> +	up_read(&pci_bus_sem);
> +
> +	return len;
> +}
> +
> +static DEVICE_ATTR_RW(aspm_l0s);
> +static DEVICE_ATTR_RW(aspm_l1);
> +static DEVICE_ATTR_RW(aspm_l1_1);
> +static DEVICE_ATTR_RW(aspm_l1_2);
> +static DEVICE_ATTR_RW(aspm_l1_1_pcipm);
> +static DEVICE_ATTR_RW(aspm_l1_2_pcipm);
> +static DEVICE_ATTR_RW(aspm_clkpm);
> +
> +static struct attribute *aspm_ctrl_attrs[] = {
> +	&dev_attr_aspm_l0s.attr,
> +	&dev_attr_aspm_l1.attr,
> +	&dev_attr_aspm_l1_1.attr,
> +	&dev_attr_aspm_l1_2.attr,
> +	&dev_attr_aspm_l1_1_pcipm.attr,
> +	&dev_attr_aspm_l1_2_pcipm.attr,
> +	&dev_attr_aspm_clkpm.attr,
> +	NULL
> +};
> +
> +static umode_t aspm_ctrl_attrs_are_visible(struct kobject *kobj,
> +					   struct attribute *a, int n)
> +{
> +	struct device *dev = kobj_to_dev(kobj);
> +	struct pci_dev *pdev = to_pci_dev(dev);
> +
> +	return pcie_check_valid_aspm_endpoint(pdev) ? a->mode : 0;
> +}
> +
> +const struct attribute_group aspm_ctrl_attr_group = {
> +	.name = "aspm",
> +	.attrs = aspm_ctrl_attrs,
> +	.is_visible = aspm_ctrl_attrs_are_visible,
> +};
> +
>  static int __init pcie_aspm_disable(char *str)
>  {
>  	if (!strcmp(str, "off")) {
> -- 
> 2.23.0
> 
> 
> 

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v5 4/4] PCI/ASPM: remove Kconfig option PCIEASPM_DEBUG and related code
  2019-08-31 20:18 ` [PATCH v5 4/4] PCI/ASPM: remove Kconfig option PCIEASPM_DEBUG and related code Heiner Kallweit
@ 2019-09-07 20:34   ` Bjorn Helgaas
  0 siblings, 0 replies; 8+ messages in thread
From: Bjorn Helgaas @ 2019-09-07 20:34 UTC (permalink / raw)
  To: Heiner Kallweit; +Cc: Frederick Lawler, Greg KH, Rajat Jain, linux-pci

On Sat, Aug 31, 2019 at 10:18:28PM +0200, Heiner Kallweit wrote:
> Now that we have sysfs attributes for enabling/disabling the individual
> ASPM link states, this debug code isn't needed any longer.

I think this removes some sysfs files, doesn't it?  Since this patch
doesn't remove any documentation, I assume there wasn't any?  IIRC we
had a little discussion on the mailing list about whether these files
were used by anybody, and the conclusion was "not really".  It'd be
nice to cite that discussion here if you can dig it up.

> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
> v5:
> - rebased to latest pci/next
> ---
>  drivers/pci/pci-sysfs.c  |   3 --
>  drivers/pci/pci.h        |   8 ---
>  drivers/pci/pcie/Kconfig |   7 ---
>  drivers/pci/pcie/aspm.c  | 105 ---------------------------------------
>  4 files changed, 123 deletions(-)
> 
> diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
> index 687240f55..acba3aff0 100644
> --- a/drivers/pci/pci-sysfs.c
> +++ b/drivers/pci/pci-sysfs.c
> @@ -1314,7 +1314,6 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev)
>  	int retval;
>  
>  	pcie_vpd_create_sysfs_dev_files(dev);
> -	pcie_aspm_create_sysfs_dev_files(dev);
>  #ifdef CONFIG_PCIEASPM
>  	/* update visibility of attributes in this group */
>  	sysfs_update_group(&dev->dev.kobj, &aspm_ctrl_attr_group);
> @@ -1328,7 +1327,6 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev)
>  	return 0;
>  
>  error:
> -	pcie_aspm_remove_sysfs_dev_files(dev);
>  	pcie_vpd_remove_sysfs_dev_files(dev);
>  	return retval;
>  }
> @@ -1404,7 +1402,6 @@ int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev)
>  static void pci_remove_capabilities_sysfs(struct pci_dev *dev)
>  {
>  	pcie_vpd_remove_sysfs_dev_files(dev);
> -	pcie_aspm_remove_sysfs_dev_files(dev);
>  	if (dev->reset_fn) {
>  		device_remove_file(&dev->dev, &dev_attr_reset);
>  		dev->reset_fn = 0;
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index 9dc3e3673..b3d3da257 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -533,14 +533,6 @@ static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) { }
>  static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { }
>  #endif
>  
> -#ifdef CONFIG_PCIEASPM_DEBUG
> -void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev);
> -void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev);
> -#else
> -static inline void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev) { }
> -static inline void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev) { }
> -#endif
> -
>  #ifdef CONFIG_PCIE_ECRC
>  void pcie_set_ecrc_checking(struct pci_dev *dev);
>  void pcie_ecrc_get_policy(char *str);
> diff --git a/drivers/pci/pcie/Kconfig b/drivers/pci/pcie/Kconfig
> index 362eb8cfa..a2e862d4e 100644
> --- a/drivers/pci/pcie/Kconfig
> +++ b/drivers/pci/pcie/Kconfig
> @@ -79,13 +79,6 @@ config PCIEASPM
>  
>  	  When in doubt, say Y.
>  
> -config PCIEASPM_DEBUG
> -	bool "Debug PCI Express ASPM"
> -	depends on PCIEASPM
> -	help
> -	  This enables PCI Express ASPM debug support. It will add per-device
> -	  interface to control ASPM.
> -
>  choice
>  	prompt "Default ASPM policy"
>  	default PCIEASPM_DEFAULT
> diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
> index ce3425125..67a142251 100644
> --- a/drivers/pci/pcie/aspm.c
> +++ b/drivers/pci/pcie/aspm.c
> @@ -1182,111 +1182,6 @@ static int pcie_aspm_get_policy(char *buffer, const struct kernel_param *kp)
>  module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy,
>  	NULL, 0644);
>  
> -#ifdef CONFIG_PCIEASPM_DEBUG
> -static ssize_t link_state_show(struct device *dev,
> -		struct device_attribute *attr,
> -		char *buf)
> -{
> -	struct pci_dev *pci_device = to_pci_dev(dev);
> -	struct pcie_link_state *link_state = pci_device->link_state;
> -
> -	return sprintf(buf, "%d\n", link_state->aspm_enabled);
> -}
> -
> -static ssize_t link_state_store(struct device *dev,
> -		struct device_attribute *attr,
> -		const char *buf,
> -		size_t n)
> -{
> -	struct pci_dev *pdev = to_pci_dev(dev);
> -	struct pcie_link_state *link, *root = pdev->link_state->root;
> -	u32 state;
> -
> -	if (aspm_disabled)
> -		return -EPERM;
> -
> -	if (kstrtouint(buf, 10, &state))
> -		return -EINVAL;
> -	if ((state & ~ASPM_STATE_ALL) != 0)
> -		return -EINVAL;
> -
> -	down_read(&pci_bus_sem);
> -	mutex_lock(&aspm_lock);
> -	list_for_each_entry(link, &link_list, sibling) {
> -		if (link->root != root)
> -			continue;
> -		pcie_config_aspm_link(link, state);
> -	}
> -	mutex_unlock(&aspm_lock);
> -	up_read(&pci_bus_sem);
> -	return n;
> -}
> -
> -static ssize_t clk_ctl_show(struct device *dev,
> -		struct device_attribute *attr,
> -		char *buf)
> -{
> -	struct pci_dev *pci_device = to_pci_dev(dev);
> -	struct pcie_link_state *link_state = pci_device->link_state;
> -
> -	return sprintf(buf, "%d\n", link_state->clkpm_enabled);
> -}
> -
> -static ssize_t clk_ctl_store(struct device *dev,
> -		struct device_attribute *attr,
> -		const char *buf,
> -		size_t n)
> -{
> -	struct pci_dev *pdev = to_pci_dev(dev);
> -	bool state;
> -
> -	if (strtobool(buf, &state))
> -		return -EINVAL;
> -
> -	down_read(&pci_bus_sem);
> -	mutex_lock(&aspm_lock);
> -	pcie_set_clkpm_nocheck(pdev->link_state, state);
> -	mutex_unlock(&aspm_lock);
> -	up_read(&pci_bus_sem);
> -
> -	return n;
> -}
> -
> -static DEVICE_ATTR_RW(link_state);
> -static DEVICE_ATTR_RW(clk_ctl);
> -
> -static char power_group[] = "power";
> -void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev)
> -{
> -	struct pcie_link_state *link_state = pdev->link_state;
> -
> -	if (!link_state)
> -		return;
> -
> -	if (link_state->aspm_support)
> -		sysfs_add_file_to_group(&pdev->dev.kobj,
> -			&dev_attr_link_state.attr, power_group);
> -	if (link_state->clkpm_capable)
> -		sysfs_add_file_to_group(&pdev->dev.kobj,
> -			&dev_attr_clk_ctl.attr, power_group);
> -}
> -
> -void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev)
> -{
> -	struct pcie_link_state *link_state = pdev->link_state;
> -
> -	if (!link_state)
> -		return;
> -
> -	if (link_state->aspm_support)
> -		sysfs_remove_file_from_group(&pdev->dev.kobj,
> -			&dev_attr_link_state.attr, power_group);
> -	if (link_state->clkpm_capable)
> -		sysfs_remove_file_from_group(&pdev->dev.kobj,
> -			&dev_attr_clk_ctl.attr, power_group);
> -}
> -#endif
> -
>  static struct pcie_link_state *aspm_get_parent_link(struct pci_dev *pdev)
>  {
>  	struct pci_dev *parent = pdev->bus->self;
> -- 
> 2.23.0
> 
> 

^ permalink raw reply	[flat|nested] 8+ messages in thread

end of thread, back to index

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-08-31 20:10 [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM Heiner Kallweit
2019-08-31 20:15 ` [PATCH v5 1/4] PCI/ASPM: add L1 sub-state support to pci_disable_link_state Heiner Kallweit
2019-08-31 20:16 ` [PATCH v5 2/4] PCI/ASPM: allow to re-enable Clock PM Heiner Kallweit
2019-08-31 20:18 ` [PATCH v5 4/4] PCI/ASPM: remove Kconfig option PCIEASPM_DEBUG and related code Heiner Kallweit
2019-09-07 20:34   ` Bjorn Helgaas
2019-08-31 20:20 ` [PATCH v5 3/4] PCI/ASPM: add sysfs attributes for controlling ASPM link states Heiner Kallweit
2019-09-07 20:32   ` Bjorn Helgaas
2019-09-07 16:58 ` [PATCH v5 0/4] PCI/ASPM: add sysfs attributes for controlling ASPM Bjorn Helgaas

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