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authorBjorn Helgaas <bhelgaas@google.com>2019-11-28 17:54:29 +0300
committerBjorn Helgaas <bhelgaas@google.com>2019-11-28 17:54:29 +0300
commitabd05c97f9711a4baa8cd43832893b8df45d459e (patch)
treec2ec4d6561dcc45bd87db28ade6a212dcdc29a19 /drivers/pci
parentc2a3d213d1bc007683f63790b1cf522d5586d1a8 (diff)
parent87e90283c94c76ee11d379ab5a0973382bbd0baf (diff)
downloadlinux-abd05c97f9711a4baa8cd43832893b8df45d459e.tar.xz
Merge branch 'pci/aspm'
- Remove unnecessary ASPM locking (Bjorn Helgaas) - Add support for disabling L1 PM Substates (Heiner Kallweit) - Allow re-enabling Clock PM after it has been disabled (Heiner Kallweit) - Add sysfs attributes for controlling ASPM link states (Heiner Kallweit) - Remove CONFIG_PCIEASPM_DEBUG, including "link_state" and "clk_ctl" sysfs files (Heiner Kallweit) * pci/aspm: PCI/ASPM: Remove PCIEASPM_DEBUG Kconfig option and related code PCI/ASPM: Add sysfs attributes for controlling ASPM link states PCI/ASPM: Add pcie_aspm_get_link() PCI/ASPM: Allow re-enabling Clock PM PCI/ASPM: Add L1 PM substate support to pci_disable_link_state() PCI/ASPM: Remove pcie_aspm_enabled() unnecessary locking
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/pci-sysfs.c6
-rw-r--r--drivers/pci/pci.h12
-rw-r--r--drivers/pci/pcie/Kconfig7
-rw-r--r--drivers/pci/pcie/aspm.c245
4 files changed, 161 insertions, 109 deletions
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 793412954529..92bf1b1ce280 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -1330,7 +1330,6 @@ 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);
if (dev->reset_fn) {
retval = device_create_file(&dev->dev, &dev_attr_reset);
@@ -1340,7 +1339,6 @@ 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;
}
@@ -1416,7 +1414,6 @@ err:
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;
@@ -1588,6 +1585,9 @@ static const struct attribute_group *pci_dev_attr_groups[] = {
#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 b96988f90315..23e06feed6cb 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -542,14 +542,6 @@ 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);
@@ -668,4 +660,8 @@ 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/Kconfig b/drivers/pci/pcie/Kconfig
index 362eb8cfa53b..a2e862d4ec21 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 652ef23bba35..0dcd44308228 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)
@@ -894,6 +899,14 @@ static struct pcie_link_state *alloc_pcie_link_state(struct pci_dev *pdev)
return link;
}
+static void pcie_aspm_update_sysfs_visibility(struct pci_dev *pdev)
+{
+ struct pci_dev *child;
+
+ list_for_each_entry(child, &pdev->subordinate->devices, bus_list)
+ sysfs_update_group(&child->dev.kobj, &aspm_ctrl_attr_group);
+}
+
/*
* pcie_aspm_init_link_state: Initiate PCI express link state.
* It is called after the pcie and its children devices are scanned.
@@ -955,6 +968,8 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev)
pcie_set_clkpm(link, policy_to_clkpm_state(link));
}
+ pcie_aspm_update_sysfs_visibility(pdev);
+
unlock:
mutex_unlock(&aspm_lock);
out:
@@ -1061,19 +1076,26 @@ void pcie_aspm_powersave_config_link(struct pci_dev *pdev)
up_read(&pci_bus_sem);
}
-static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
+static struct pcie_link_state *pcie_aspm_get_link(struct pci_dev *pdev)
{
- struct pci_dev *parent = pdev->bus->self;
- struct pcie_link_state *link;
+ struct pci_dev *bridge;
if (!pci_is_pcie(pdev))
- return 0;
+ return NULL;
- if (pcie_downstream_port(pdev))
- parent = pdev;
- if (!parent || !parent->link_state)
- return -EINVAL;
+ bridge = pci_upstream_bridge(pdev);
+ if (!bridge || !pci_is_pcie(bridge))
+ return NULL;
+ return bridge->link_state;
+}
+
+static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
+{
+ struct pcie_link_state *link = pcie_aspm_get_link(pdev);
+
+ if (!link)
+ return -EINVAL;
/*
* A driver requested that ASPM be disabled on this device, but
* if we don't have permission to manage ASPM (e.g., on ACPI
@@ -1090,17 +1112,24 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
if (sem)
down_read(&pci_bus_sem);
mutex_lock(&aspm_lock);
- link = parent->link_state;
if (state & PCIE_LINK_STATE_L0S)
link->aspm_disable |= ASPM_STATE_L0S;
if (state & PCIE_LINK_STATE_L1)
- link->aspm_disable |= ASPM_STATE_L1;
+ /* L1 PM substates 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) {
- 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);
@@ -1172,127 +1201,161 @@ module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy,
/**
* pcie_aspm_enabled - Check if PCIe ASPM has been enabled for a device.
* @pdev: Target device.
+ *
+ * Relies on the upstream bridge's link_state being valid. The link_state
+ * is deallocated only when the last child of the bridge (i.e., @pdev or a
+ * sibling) is removed, and the caller should be holding a reference to
+ * @pdev, so this should be safe.
*/
bool pcie_aspm_enabled(struct pci_dev *pdev)
{
- struct pci_dev *bridge = pci_upstream_bridge(pdev);
- bool ret;
+ struct pcie_link_state *link = pcie_aspm_get_link(pdev);
- if (!bridge)
+ if (!link)
return false;
- mutex_lock(&aspm_lock);
- ret = bridge->link_state ? !!bridge->link_state->aspm_enabled : false;
- mutex_unlock(&aspm_lock);
-
- return ret;
+ return link->aspm_enabled;
}
EXPORT_SYMBOL_GPL(pcie_aspm_enabled);
-#ifdef CONFIG_PCIEASPM_DEBUG
-static ssize_t link_state_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
+static ssize_t aspm_attr_show_common(struct device *dev,
+ struct device_attribute *attr,
+ char *buf, u8 state)
{
- struct pci_dev *pci_device = to_pci_dev(dev);
- struct pcie_link_state *link_state = pci_device->link_state;
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct pcie_link_state *link = pcie_aspm_get_link(pdev);
- return sprintf(buf, "%d\n", link_state->aspm_enabled);
+ return sprintf(buf, "%d\n", (link->aspm_enabled & state) ? 1 : 0);
}
-static ssize_t link_state_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t n)
+static ssize_t aspm_attr_store_common(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len, u8 state)
{
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;
+ struct pcie_link_state *link = pcie_aspm_get_link(pdev);
+ bool state_enable;
- if (kstrtouint(buf, 10, &state))
- return -EINVAL;
- if ((state & ~ASPM_STATE_ALL) != 0)
+ if (strtobool(buf, &state_enable) < 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);
+
+ if (state_enable) {
+ link->aspm_disable &= ~state;
+ /* need to enable L1 for substates */
+ 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 n;
+
+ return len;
}
-static ssize_t clk_ctl_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
+#define ASPM_ATTR(_f, _s) \
+static ssize_t _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 _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_aspm, L0S)
+ASPM_ATTR(l1_aspm, L1)
+ASPM_ATTR(l1_1_aspm, L1_1)
+ASPM_ATTR(l1_2_aspm, L1_2)
+ASPM_ATTR(l1_1_pcipm, L1_1_PCIPM)
+ASPM_ATTR(l1_2_pcipm, L1_2_PCIPM)
+
+static ssize_t clkpm_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;
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct pcie_link_state *link = pcie_aspm_get_link(pdev);
- return sprintf(buf, "%d\n", link_state->clkpm_enabled);
+ return sprintf(buf, "%d\n", link->clkpm_enabled);
}
-static ssize_t clk_ctl_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t n)
+static ssize_t clkpm_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
{
struct pci_dev *pdev = to_pci_dev(dev);
- bool state;
+ struct pcie_link_state *link = pcie_aspm_get_link(pdev);
+ bool state_enable;
- if (strtobool(buf, &state))
+ if (strtobool(buf, &state_enable) < 0)
return -EINVAL;
down_read(&pci_bus_sem);
mutex_lock(&aspm_lock);
- pcie_set_clkpm_nocheck(pdev->link_state, state);
+
+ link->clkpm_disable = !state_enable;
+ pcie_set_clkpm(link, policy_to_clkpm_state(link));
+
mutex_unlock(&aspm_lock);
up_read(&pci_bus_sem);
- return n;
+ return len;
}
-static DEVICE_ATTR_RW(link_state);
-static DEVICE_ATTR_RW(clk_ctl);
+static DEVICE_ATTR_RW(clkpm);
+static DEVICE_ATTR_RW(l0s_aspm);
+static DEVICE_ATTR_RW(l1_aspm);
+static DEVICE_ATTR_RW(l1_1_aspm);
+static DEVICE_ATTR_RW(l1_2_aspm);
+static DEVICE_ATTR_RW(l1_1_pcipm);
+static DEVICE_ATTR_RW(l1_2_pcipm);
+
+static struct attribute *aspm_ctrl_attrs[] = {
+ &dev_attr_clkpm.attr,
+ &dev_attr_l0s_aspm.attr,
+ &dev_attr_l1_aspm.attr,
+ &dev_attr_l1_1_aspm.attr,
+ &dev_attr_l1_2_aspm.attr,
+ &dev_attr_l1_1_pcipm.attr,
+ &dev_attr_l1_2_pcipm.attr,
+ NULL
+};
-static char power_group[] = "power";
-void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev)
+static umode_t aspm_ctrl_attrs_are_visible(struct kobject *kobj,
+ struct attribute *a, int n)
{
- 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);
-}
+ struct device *dev = kobj_to_dev(kobj);
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct pcie_link_state *link = pcie_aspm_get_link(pdev);
+ static const u8 aspm_state_map[] = {
+ ASPM_STATE_L0S,
+ ASPM_STATE_L1,
+ ASPM_STATE_L1_1,
+ ASPM_STATE_L1_2,
+ ASPM_STATE_L1_1_PCIPM,
+ ASPM_STATE_L1_2_PCIPM,
+ };
-void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev)
-{
- struct pcie_link_state *link_state = pdev->link_state;
+ if (aspm_disabled || !link)
+ return 0;
- if (!link_state)
- return;
+ if (n == 0)
+ return link->clkpm_capable ? a->mode : 0;
- 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);
+ return link->aspm_capable & aspm_state_map[n - 1] ? a->mode : 0;
}
-#endif
+
+const struct attribute_group aspm_ctrl_attr_group = {
+ .name = "link",
+ .attrs = aspm_ctrl_attrs,
+ .is_visible = aspm_ctrl_attrs_are_visible,
+};
static int __init pcie_aspm_disable(char *str)
{