Commit 7cf2cba4 authored by Bjorn Helgaas's avatar Bjorn Helgaas
Browse files

PCI: Unify ACS quirk desired vs provided checking 



Most of the ACS quirks have a similar pattern of:

  acs_flags &= ~( <controls provided by this device> );
  return acs_flags ? 0 : 1;

Pull this out into a helper function to simplify the quirks slightly.  The
helper function is also a convenient place for comments about what the list
of ACS controls means.  No functional change intended.

Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent c8de8ed2

drivers/pci/quirks.c

+45 −22
Original line number Diff line number Diff line
@@ -4296,6 +4296,24 @@ static void quirk_chelsio_T5_disable_root_port_attributes(struct pci_dev *pdev) 
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CHELSIO, PCI_ANY_ID,

			 quirk_chelsio_T5_disable_root_port_attributes);



/*

 * pci_acs_ctrl_enabled - compare desired ACS controls with those provided

 *			  by a device

 * @acs_ctrl_req: Bitmask of desired ACS controls

 * @acs_ctrl_ena: Bitmask of ACS controls enabled or provided implicitly by

 *		  the hardware design

 *

 * Return 1 if all ACS controls in the @acs_ctrl_req bitmask are included

 * in @acs_ctrl_ena, i.e., the device provides all the access controls the

 * caller desires.  Return 0 otherwise.

 */

static int pci_acs_ctrl_enabled(u16 acs_ctrl_req, u16 acs_ctrl_ena)

{

	if ((acs_ctrl_req & acs_ctrl_ena) == acs_ctrl_req)

		return 1;

	return 0;

}



/*

 * AMD has indicated that the devices below do not support peer-to-peer

 * in any system where they are found in the southbridge with an AMD
@@ -4339,7 +4357,7 @@ static int pci_quirk_amd_sb_acs(struct pci_dev *dev, u16 acs_flags) 
	/* Filter out flags not applicable to multifunction */

	acs_flags &= (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_EC | PCI_ACS_DT);



	return acs_flags & ~(PCI_ACS_RR | PCI_ACS_CR) ? 0 : 1;

	return pci_acs_ctrl_enabled(acs_flags, PCI_ACS_RR | PCI_ACS_CR);

#else

	return -ENODEV;

#endif
@@ -4377,9 +4395,8 @@ static int pci_quirk_cavium_acs(struct pci_dev *dev, u16 acs_flags) 
	 * hardware implements and enables equivalent ACS functionality for

	 * these flags.

	 */

	acs_flags &= ~(PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);



	return acs_flags ? 0 : 1;

	return pci_acs_ctrl_enabled(acs_flags,

		PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);

}



static int pci_quirk_xgene_acs(struct pci_dev *dev, u16 acs_flags)
@@ -4389,9 +4406,8 @@ static int pci_quirk_xgene_acs(struct pci_dev *dev, u16 acs_flags) 
	 * transactions with others, allowing masking out these bits as if they

	 * were unimplemented in the ACS capability.

	 */

	acs_flags &= ~(PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);



	return acs_flags ? 0 : 1;

	return pci_acs_ctrl_enabled(acs_flags,

		PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);

}



/*
@@ -4443,17 +4459,16 @@ static bool pci_quirk_intel_pch_acs_match(struct pci_dev *dev) 
	return false;

}



#define INTEL_PCH_ACS_FLAGS (PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF)



static int pci_quirk_intel_pch_acs(struct pci_dev *dev, u16 acs_flags)

{

	if (!pci_quirk_intel_pch_acs_match(dev))

		return -ENOTTY;



	if (dev->dev_flags & PCI_DEV_FLAGS_ACS_ENABLED_QUIRK)

		acs_flags &= ~(INTEL_PCH_ACS_FLAGS);

		return pci_acs_ctrl_enabled(acs_flags,

			PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);



	return acs_flags ? 0 : 1;

	return pci_acs_ctrl_enabled(acs_flags, 0);

}



/*
@@ -4468,9 +4483,8 @@ static int pci_quirk_intel_pch_acs(struct pci_dev *dev, u16 acs_flags) 
 */

static int pci_quirk_qcom_rp_acs(struct pci_dev *dev, u16 acs_flags)

{

	acs_flags &= ~(PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);



	return acs_flags ? 0 : 1;

	return pci_acs_ctrl_enabled(acs_flags,

		PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);

}



static int pci_quirk_al_acs(struct pci_dev *dev, u16 acs_flags)
@@ -4571,7 +4585,7 @@ static int pci_quirk_intel_spt_pch_acs(struct pci_dev *dev, u16 acs_flags) 


	pci_read_config_dword(dev, pos + INTEL_SPT_ACS_CTRL, &ctrl);



	return acs_flags & ~ctrl ? 0 : 1;

	return pci_acs_ctrl_enabled(acs_flags, ctrl);

}



static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags)
@@ -4585,10 +4599,9 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags) 
	 * perform peer-to-peer with other functions, allowing us to mask out

	 * these bits as if they were unimplemented in the ACS capability.

	 */

	acs_flags &= ~(PCI_ACS_SV | PCI_ACS_TB | PCI_ACS_RR |

	return pci_acs_ctrl_enabled(acs_flags,

		PCI_ACS_SV | PCI_ACS_TB | PCI_ACS_RR |

		PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_DT);



	return acs_flags ? 0 : 1;

}



static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags)
@@ -4599,9 +4612,8 @@ static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags) 
	 * Allow each Root Port to be in a separate IOMMU group by masking

	 * SV/RR/CR/UF bits.

	 */

	acs_flags &= ~(PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);



	return acs_flags ? 0 : 1;

	return pci_acs_ctrl_enabled(acs_flags,

		PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);

}



static const struct pci_dev_acs_enabled {
@@ -4703,6 +4715,17 @@ static const struct pci_dev_acs_enabled { 
	{ 0 }

};



/*

 * pci_dev_specific_acs_enabled - check whether device provides ACS controls

 * @dev:	PCI device

 * @acs_flags:	Bitmask of desired ACS controls

 *

 * Returns:

 *   -ENOTTY:	No quirk applies to this device; we can't tell whether the

 *		device provides the desired controls

 *   0:		Device does not provide all the desired controls

 *   >0:	Device provides all the controls in @acs_flags

 */

int pci_dev_specific_acs_enabled(struct pci_dev *dev, u16 acs_flags)

{

	const struct pci_dev_acs_enabled *i;