[+cc Alex] On Tue, Aug 20, 2019 at 10:09:45AM +0530, Srinath Mannam wrote: > From: Abhinav Ratna <abhinav.ratna@xxxxxxxxxxxx> > > IPROC PAXB RC doesn't support ACS capabilities and control registers. > Add quirk to have separate IOMMU groups for all EPs and functions connected > to root port, by masking RR/CR/SV/UF bits. > > Signed-off-by: Abhinav Ratna <abhinav.ratna@xxxxxxxxxxxx> > Signed-off-by: Srinath Mannam <srinath.mannam@xxxxxxxxxxxx> I tentatively applied this to pci/misc with Scott's ack for v5.4. I tweaked the patch itself to follow the style of similar quirks (interdiff is below, plus a diff of the commit log). Please make sure I didn't break it. I also went out on a limb and reworded the comment to give what I *think* is the justification for this patch, as opposed to merely a description of the code. I'm making a lot of assumptions there, so please confirm that they're correct, or supply alternate justification if they're not. > --- > drivers/pci/quirks.c | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c > index 0f16acc..f9584c0 100644 > --- a/drivers/pci/quirks.c > +++ b/drivers/pci/quirks.c > @@ -4466,6 +4466,21 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags) > return acs_flags ? 0 : 1; > } > > +static int pcie_quirk_brcm_bridge_acs(struct pci_dev *dev, u16 acs_flags) > +{ > + /* > + * IPROC PAXB RC doesn't support ACS capabilities and control registers. > + * Add quirk to to have separate IOMMU groups for all EPs and functions > + * connected to root port, by masking RR/CR/SV/UF bits. > + */ > + > + u16 flags = (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV); > + int ret = acs_flags & ~flags ? 0 : 1; > + > + return ret; > +} > + > + > static const struct pci_dev_acs_enabled { > u16 vendor; > u16 device; > @@ -4559,6 +4574,7 @@ static const struct pci_dev_acs_enabled { > { PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs }, > { PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs }, > { PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs }, > + { PCI_VENDOR_ID_BROADCOM, 0xD714, pcie_quirk_brcm_bridge_acs }, > { 0 } > }; diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 77c0330ac922..2edbce35e8c5 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4466,21 +4466,19 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags) return acs_flags ? 0 : 1; } -static int pcie_quirk_brcm_bridge_acs(struct pci_dev *dev, u16 acs_flags) +static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags) { /* - * IPROC PAXB RC doesn't support ACS capabilities and control registers. - * Add quirk to to have separate IOMMU groups for all EPs and functions - * connected to root port, by masking RR/CR/SV/UF bits. + * iProc PAXB Root Ports don't advertise an ACS capability, but + * they do not allow peer-to-peer transactions between Root Ports. + * 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); - u16 flags = (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV); - int ret = acs_flags & ~flags ? 0 : 1; - - return ret; + return acs_flags ? 0 : 1; } - static const struct pci_dev_acs_enabled { u16 vendor; u16 device; @@ -4574,7 +4572,7 @@ static const struct pci_dev_acs_enabled { { PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs }, { PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs }, { PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs }, - { PCI_VENDOR_ID_BROADCOM, 0xD714, pcie_quirk_brcm_bridge_acs }, + { PCI_VENDOR_ID_BROADCOM, 0xD714, pci_quirk_brcm_acs }, { 0 } }; @@ -1,49 +1,49 @@ -commit b50ae502eff0 +commit 46b2c32df7a4 Author: Abhinav Ratna <abhinav.ratna@xxxxxxxxxxxx> Date: Tue Aug 20 10:09:45 2019 +0530 - PCI: Add PCIE ACS quirk for IPROC PAXB + PCI: Add ACS quirk for iProc PAXB - IPROC PAXB RC doesn't support ACS capabilities and control registers. - Add quirk to have separate IOMMU groups for all EPs and functions connected - to root port, by masking RR/CR/SV/UF bits. + iProc PAXB Root Ports don't advertise an ACS capability, but they do not + allow peer-to-peer transactions between Root Ports. Add an ACS quirk so + each Root Port can be in a separate IOMMU group. + [bhelgaas: commit log, comment, use common implementation style] Link: https://lore.kernel.org/r/1566275985-25670-1-git-send-email-srinath.mannam@xxxxxxxxxxxx Signed-off-by: Abhinav Ratna <abhinav.ratna@xxxxxxxxxxxx> Signed-off-by: Srinath Mannam <srinath.mannam@xxxxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> + Acked-by: Scott Branden <scott.branden@xxxxxxxxxxxx>