From 76e67e9e0f0f2debf9df192502a759bdd0cb4dab Mon Sep 17 00:00:00 2001 From: Ali Saidi Date: Thu, 12 Sep 2019 16:00:40 +0300 Subject: PCI: Add ACS quirk for Amazon Annapurna Labs root ports The Amazon's Annapurna Labs root ports don't advertise an ACS capability, but they don't allow peer-to-peer transactions and do validate bus numbers through the SMMU. Additionally, it's not possible for one RP to pass traffic to another RP. Signed-off-by: Ali Saidi Signed-off-by: Jonathan Chocron Signed-off-by: Lorenzo Pieralisi Reviewed-by: Gustavo Pimentel Reviewed-by: Andrew Murray Acked-by: Bjorn Helgaas --- drivers/pci/quirks.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'drivers/pci/quirks.c') diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 208aacf39329..e96c03b4e494 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4366,6 +4366,24 @@ static int pci_quirk_qcom_rp_acs(struct pci_dev *dev, u16 acs_flags) return ret; } +static int pci_quirk_al_acs(struct pci_dev *dev, u16 acs_flags) +{ + if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) + return -ENOTTY; + + /* + * Amazon's Annapurna Labs root ports don't include an ACS capability, + * but do include ACS-like functionality. The hardware doesn't support + * peer-to-peer transactions via the root port and each has a unique + * segment number. + * + * Additionally, the root ports cannot send traffic to each other. + */ + acs_flags &= ~(PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF); + + return acs_flags ? 0 : 1; +} + /* * Sunrise Point PCH root ports implement ACS, but unfortunately as shown in * the datasheet (Intel 100 Series Chipset Family PCH Datasheet, Vol. 2, @@ -4559,6 +4577,8 @@ 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 }, + /* Amazon Annapurna Labs */ + { PCI_VENDOR_ID_AMAZON_ANNAPURNA_LABS, 0x0031, pci_quirk_al_acs }, { 0 } }; -- cgit v1.2.3