From d2481b5d1257c2c47181ee735741ac4dc547f365 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Fri, 6 Sep 2019 18:36:06 -0500 Subject: [PATCH] PCI: Unify ACS quirk desired vs provided checking commit 7cf2cba43f15c74bac46dc5f0326805d25ef514d upstream. Most of the ACS quirks have a similar pattern of: acs_flags &= ~( ); 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: Bjorn Helgaas Reviewed-by: Logan Gunthorpe Reviewed-by: Alex Williamson Signed-off-by: Greg Kroah-Hartman --- drivers/pci/quirks.c | 67 +++++++++++++++++++++++++++++--------------- 1 file changed, 45 insertions(+), 22 deletions(-) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 2b413a3a3358..fbbf6c325d33 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4352,6 +4352,24 @@ 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 @@ -4395,7 +4413,7 @@ 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 @@ -4433,9 +4451,8 @@ 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) @@ -4445,9 +4462,8 @@ 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); } /* @@ -4499,17 +4515,16 @@ 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); } /* @@ -4524,9 +4539,8 @@ 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) @@ -4627,7 +4641,7 @@ 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) @@ -4641,10 +4655,9 @@ 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 | - PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_DT); - - return acs_flags ? 0 : 1; + 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); } static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags) @@ -4655,9 +4668,8 @@ 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 { @@ -4763,6 +4775,17 @@ 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; -- 2.34.1