Commit cbe42036 authored by Rajat Jain's avatar Rajat Jain Committed by Bjorn Helgaas
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PCI: Reorder pci_enable_acs() and dependencies 

Move pci_enable_acs() and dependencies further up in the source code to
avoid having to forward declare it when we make it static in near future.

No functional changes intended.

Link: https://lore.kernel.org/r/20200707224604.3737893-1-rajatja@google.com


Signed-off-by: default avatarRajat Jain <rajatja@google.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 2194bc7c

drivers/pci/pci.c

+127 −127
Original line number Diff line number Diff line
@@ -777,6 +777,133 @@ int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask) 
	return 0;

}



static int pci_acs_enable;



/**

 * pci_request_acs - ask for ACS to be enabled if supported

 */

void pci_request_acs(void)

{

	pci_acs_enable = 1;

}



static const char *disable_acs_redir_param;



/**

 * pci_disable_acs_redir - disable ACS redirect capabilities

 * @dev: the PCI device

 *

 * For only devices specified in the disable_acs_redir parameter.

 */

static void pci_disable_acs_redir(struct pci_dev *dev)

{

	int ret = 0;

	const char *p;

	int pos;

	u16 ctrl;



	if (!disable_acs_redir_param)

		return;



	p = disable_acs_redir_param;

	while (*p) {

		ret = pci_dev_str_match(dev, p, &p);

		if (ret < 0) {

			pr_info_once("PCI: Can't parse disable_acs_redir parameter: %s\n",

				     disable_acs_redir_param);



			break;

		} else if (ret == 1) {

			/* Found a match */

			break;

		}



		if (*p != ';' && *p != ',') {

			/* End of param or invalid format */

			break;

		}

		p++;

	}



	if (ret != 1)

		return;



	if (!pci_dev_specific_disable_acs_redir(dev))

		return;



	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);

	if (!pos) {

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

		return;

	}



	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);



	/* P2P Request & Completion Redirect */

	ctrl &= ~(PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_EC);



	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);



	pci_info(dev, "disabled ACS redirect\n");

}



/**

 * pci_std_enable_acs - enable ACS on devices using standard ACS capabilities

 * @dev: the PCI device

 */

static void pci_std_enable_acs(struct pci_dev *dev)

{

	int pos;

	u16 cap;

	u16 ctrl;



	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);

	if (!pos)

		return;



	pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);

	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);



	/* Source Validation */

	ctrl |= (cap & PCI_ACS_SV);



	/* P2P Request Redirect */

	ctrl |= (cap & PCI_ACS_RR);



	/* P2P Completion Redirect */

	ctrl |= (cap & PCI_ACS_CR);



	/* Upstream Forwarding */

	ctrl |= (cap & PCI_ACS_UF);



	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);

}



/**

 * pci_enable_acs - enable ACS if hardware support it

 * @dev: the PCI device

 */

void pci_enable_acs(struct pci_dev *dev)

{

	if (!pci_acs_enable)

		goto disable_acs_redir;



	if (!pci_dev_specific_enable_acs(dev))

		goto disable_acs_redir;



	pci_std_enable_acs(dev);



disable_acs_redir:

	/*

	 * Note: pci_disable_acs_redir() must be called even if ACS was not

	 * enabled by the kernel because it may have been enabled by

	 * platform firmware.  So if we are told to disable it, we should

	 * always disable it after setting the kernel's default

	 * preferences.

	 */

	pci_disable_acs_redir(dev);

}



/**

 * pci_restore_bars - restore a device's BAR values (e.g. after wake-up)

 * @dev: PCI device to have its BARs restored
@@ -3230,133 +3357,6 @@ void pci_configure_ari(struct pci_dev *dev) 
	}

}



static int pci_acs_enable;



/**

 * pci_request_acs - ask for ACS to be enabled if supported

 */

void pci_request_acs(void)

{

	pci_acs_enable = 1;

}



static const char *disable_acs_redir_param;



/**

 * pci_disable_acs_redir - disable ACS redirect capabilities

 * @dev: the PCI device

 *

 * For only devices specified in the disable_acs_redir parameter.

 */

static void pci_disable_acs_redir(struct pci_dev *dev)

{

	int ret = 0;

	const char *p;

	int pos;

	u16 ctrl;



	if (!disable_acs_redir_param)

		return;



	p = disable_acs_redir_param;

	while (*p) {

		ret = pci_dev_str_match(dev, p, &p);

		if (ret < 0) {

			pr_info_once("PCI: Can't parse disable_acs_redir parameter: %s\n",

				     disable_acs_redir_param);



			break;

		} else if (ret == 1) {

			/* Found a match */

			break;

		}



		if (*p != ';' && *p != ',') {

			/* End of param or invalid format */

			break;

		}

		p++;

	}



	if (ret != 1)

		return;



	if (!pci_dev_specific_disable_acs_redir(dev))

		return;



	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);

	if (!pos) {

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

		return;

	}



	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);



	/* P2P Request & Completion Redirect */

	ctrl &= ~(PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_EC);



	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);



	pci_info(dev, "disabled ACS redirect\n");

}



/**

 * pci_std_enable_acs - enable ACS on devices using standard ACS capabilities

 * @dev: the PCI device

 */

static void pci_std_enable_acs(struct pci_dev *dev)

{

	int pos;

	u16 cap;

	u16 ctrl;



	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);

	if (!pos)

		return;



	pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);

	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);



	/* Source Validation */

	ctrl |= (cap & PCI_ACS_SV);



	/* P2P Request Redirect */

	ctrl |= (cap & PCI_ACS_RR);



	/* P2P Completion Redirect */

	ctrl |= (cap & PCI_ACS_CR);



	/* Upstream Forwarding */

	ctrl |= (cap & PCI_ACS_UF);



	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);

}



/**

 * pci_enable_acs - enable ACS if hardware support it

 * @dev: the PCI device

 */

void pci_enable_acs(struct pci_dev *dev)

{

	if (!pci_acs_enable)

		goto disable_acs_redir;



	if (!pci_dev_specific_enable_acs(dev))

		goto disable_acs_redir;



	pci_std_enable_acs(dev);



disable_acs_redir:

	/*

	 * Note: pci_disable_acs_redir() must be called even if ACS was not

	 * enabled by the kernel because it may have been enabled by

	 * platform firmware.  So if we are told to disable it, we should

	 * always disable it after setting the kernel's default

	 * preferences.

	 */

	pci_disable_acs_redir(dev);

}



static bool pci_acs_flags_enabled(struct pci_dev *pdev, u16 acs_flags)

{

	int pos;

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