Commit 52fbf5bd authored by Rajat Jain's avatar Rajat Jain Committed by Bjorn Helgaas
Browse files

PCI: Cache ACS capability offset in device 

Currently the ACS capability is being looked up at a number of places. Read
and store it once at enumeration so that it can be used by all later.  No
functional change intended.

Link: https://lore.kernel.org/r/20200707224604.3737893-2-rajatja@google.com


Signed-off-by: default avatarRajat Jain <rajatja@google.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent cbe42036

drivers/pci/p2pdma.c

+1 −1
Original line number Diff line number Diff line
@@ -253,7 +253,7 @@ static int pci_bridge_has_acs_redir(struct pci_dev *pdev) 
	int pos;

	u16 ctrl;



	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ACS);

	pos = pdev->acs_cap;

	if (!pos)

		return 0;

drivers/pci/pci.c

+16 −4
Original line number Diff line number Diff line
@@ -831,7 +831,7 @@ static void pci_disable_acs_redir(struct pci_dev *dev) 
	if (!pci_dev_specific_disable_acs_redir(dev))

		return;



	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);

	pos = dev->acs_cap;

	if (!pos) {

		pci_warn(dev, "cannot disable ACS redirect for this hardware as it does not have ACS capabilities\n");

		return;
@@ -857,7 +857,7 @@ static void pci_std_enable_acs(struct pci_dev *dev) 
	u16 cap;

	u16 ctrl;



	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);

	pos = dev->acs_cap;

	if (!pos)

		return;
@@ -883,7 +883,7 @@ static void pci_std_enable_acs(struct pci_dev *dev) 
 * pci_enable_acs - enable ACS if hardware support it

 * @dev: the PCI device

 */

void pci_enable_acs(struct pci_dev *dev)

static void pci_enable_acs(struct pci_dev *dev)

{

	if (!pci_acs_enable)

		goto disable_acs_redir;
@@ -3362,7 +3362,7 @@ static bool pci_acs_flags_enabled(struct pci_dev *pdev, u16 acs_flags) 
	int pos;

	u16 cap, ctrl;



	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ACS);

	pos = pdev->acs_cap;

	if (!pos)

		return false;
@@ -3487,6 +3487,18 @@ bool pci_acs_path_enabled(struct pci_dev *start, 
	return true;

}



/**

 * pci_acs_init - Initialize ACS if hardware supports it

 * @dev: the PCI device

 */

void pci_acs_init(struct pci_dev *dev)

{

	dev->acs_cap = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);



	if (dev->acs_cap)

		pci_enable_acs(dev);

}



/**

 * pci_rebar_find_pos - find position of resize ctrl reg for BAR

 * @pdev: PCI device

drivers/pci/pci.h

+1 −1
Original line number Diff line number Diff line
@@ -532,7 +532,7 @@ static inline resource_size_t pci_resource_alignment(struct pci_dev *dev, 
	return resource_alignment(res);

}



void pci_enable_acs(struct pci_dev *dev);

void pci_acs_init(struct pci_dev *dev);

#ifdef CONFIG_PCI_QUIRKS

int pci_dev_specific_acs_enabled(struct pci_dev *dev, u16 acs_flags);

int pci_dev_specific_enable_acs(struct pci_dev *dev);

drivers/pci/probe.c

+1 −1
Original line number Diff line number Diff line
@@ -2390,7 +2390,7 @@ static void pci_init_capabilities(struct pci_dev *dev) 
	pci_ats_init(dev);		/* Address Translation Services */

	pci_pri_init(dev);		/* Page Request Interface */

	pci_pasid_init(dev);		/* Process Address Space ID */

	pci_enable_acs(dev);		/* Enable ACS P2P upstream forwarding */

	pci_acs_init(dev);		/* Access Control Services */

	pci_ptm_init(dev);		/* Precision Time Measurement */

	pci_aer_init(dev);		/* Advanced Error Reporting */

	pci_dpc_init(dev);		/* Downstream Port Containment */

drivers/pci/quirks.c

+4 −4
Original line number Diff line number Diff line
@@ -4653,7 +4653,7 @@ static int pci_quirk_intel_spt_pch_acs(struct pci_dev *dev, u16 acs_flags) 
	if (!pci_quirk_intel_spt_pch_acs_match(dev))

		return -ENOTTY;



	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);

	pos = dev->acs_cap;

	if (!pos)

		return -ENOTTY;
@@ -4961,7 +4961,7 @@ static int pci_quirk_enable_intel_spt_pch_acs(struct pci_dev *dev) 
	if (!pci_quirk_intel_spt_pch_acs_match(dev))

		return -ENOTTY;



	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);

	pos = dev->acs_cap;

	if (!pos)

		return -ENOTTY;
@@ -4988,7 +4988,7 @@ static int pci_quirk_disable_intel_spt_pch_acs_redir(struct pci_dev *dev) 
	if (!pci_quirk_intel_spt_pch_acs_match(dev))

		return -ENOTTY;



	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);

	pos = dev->acs_cap;

	if (!pos)

		return -ENOTTY;
@@ -5355,7 +5355,7 @@ int pci_idt_bus_quirk(struct pci_bus *bus, int devfn, u32 *l, int timeout) 
	bool found;

	struct pci_dev *bridge = bus->self;



	pos = pci_find_ext_capability(bridge, PCI_EXT_CAP_ID_ACS);

	pos = bridge->acs_cap;



	/* Disable ACS SV before initial config reads */

	if (pos) {

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