Commit 5352a44a authored by Mika Westerberg's avatar Mika Westerberg Committed by Bjorn Helgaas
Browse files

PCI: pciehp: Make pciehp_is_native() stricter 



Previously pciehp_is_native() returned true for any PCI device in a
hierarchy where _OSC says we can use pciehp.  This is incorrect because
bridges without PCI_EXP_SLTCAP_HPC capability should be managed by acpiphp
instead.

Improve pciehp_is_native() to return true only when PCI_EXP_SLTCAP_HPC is
set and the pciehp driver is present.  In any other case return false
to let acpiphp handle those.

Suggested-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: remove NULL pointer check]
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 9310f0dc

drivers/pci/pci-acpi.c

+14 −12
Original line number Diff line number Diff line
@@ -370,26 +370,28 @@ EXPORT_SYMBOL_GPL(pci_get_hp_params); 


/**

 * pciehp_is_native - Check whether a hotplug port is handled by the OS

 * @pdev: Hotplug port to check

 * @bridge: Hotplug port to check

 *

 * Walk up from @pdev to the host bridge, obtain its cached _OSC Control Field

 * and return the value of the "PCI Express Native Hot Plug control" bit.

 * On failure to obtain the _OSC Control Field return %false.

 * Returns true if the given @bridge is handled by the native PCIe hotplug

 * driver.

 */

bool pciehp_is_native(struct pci_dev *pdev)

bool pciehp_is_native(struct pci_dev *bridge)

{

	struct acpi_pci_root *root;

	acpi_handle handle;

	const struct pci_host_bridge *host;

	u32 slot_cap;



	handle = acpi_find_root_bridge_handle(pdev);

	if (!handle)

	if (!IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))

		return false;



	root = acpi_pci_find_root(handle);

	if (!root)

	pcie_capability_read_dword(bridge, PCI_EXP_SLTCAP, &slot_cap);

	if (!(slot_cap & PCI_EXP_SLTCAP_HPC))

		return false;



	return root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;

	if (pcie_ports_native)

		return true;



	host = pci_find_host_bridge(bridge->bus);

	return host->native_pcie_hotplug;

}



/**

drivers/pci/pcie/portdrv.h

+0 −2
Original line number Diff line number Diff line
@@ -11,8 +11,6 @@ 


#include <linux/compiler.h>



extern bool pcie_ports_native;



/* Service Type */

#define PCIE_PORT_SERVICE_PME_SHIFT	0	/* Power Management Event */

#define PCIE_PORT_SERVICE_PME		(1 << PCIE_PORT_SERVICE_PME_SHIFT)

include/linux/pci.h

+2 −0
Original line number Diff line number Diff line
@@ -1454,8 +1454,10 @@ static inline int pci_irqd_intx_xlate(struct irq_domain *d, 


#ifdef CONFIG_PCIEPORTBUS

extern bool pcie_ports_disabled;

extern bool pcie_ports_native;

#else

#define pcie_ports_disabled	true

#define pcie_ports_native	false

#endif



#ifdef CONFIG_PCIEASPM

include/linux/pci_hotplug.h

+2 −2
Original line number Diff line number Diff line
@@ -162,7 +162,7 @@ struct hotplug_params { 
#ifdef CONFIG_ACPI

#include <linux/acpi.h>

int pci_get_hp_params(struct pci_dev *dev, struct hotplug_params *hpp);

bool pciehp_is_native(struct pci_dev *pdev);

bool pciehp_is_native(struct pci_dev *bridge);

int acpi_get_hp_hw_control_from_firmware(struct pci_dev *dev, u32 flags);

int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle);

int acpi_pci_detect_ejectable(acpi_handle handle);
@@ -172,6 +172,6 @@ static inline int pci_get_hp_params(struct pci_dev *dev, 
{

	return -ENODEV;

}

static inline bool pciehp_is_native(struct pci_dev *pdev) { return true; }

static inline bool pciehp_is_native(struct pci_dev *bridge) { return true; }

#endif

#endif

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