[PATCH] PCI: Add ACS quirk for Wangxun NICs

From: Mengyuan Lou <mengyuanlou@net-swift.com>
To: netdev@vger.kernel.org
Cc: linux-pci@vger.kernel.org, helgaas@kernel.org,
	Mengyuan Lou <mengyuanlou@net-swift.com>
Subject: [PATCH] PCI: Add ACS quirk for Wangxun NICs
Date: Tue,  7 Feb 2023 18:24:19 +0800	[thread overview]
Message-ID: <20230207102419.44326-1-mengyuanlou@net-swift.com> (raw)

Wangxun has verified there is no peer-to-peer between functions for the
below selection of SFxxx, RP1000 and RP2000 NICS.
They may be multi-function device, but the hardware does not advertise
ACS capability.

Add an ACS quirk for these devices so the functions can be in
independent IOMMU groups.

Signed-off-by: Mengyuan Lou <mengyuanlou@net-swift.com>
---
 drivers/pci/quirks.c    | 22 ++++++++++++++++++++++
 include/linux/pci_ids.h |  2 ++
 2 files changed, 24 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 285acc4aaccc..13290048beda 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4835,6 +4835,26 @@ static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags)
 		PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);
 }
 
+/*
+ * Wangxun 10G/1G NICs have no ACS capability, and on multi-function
+ * devices, peer-to-peer transactions are not be used between the functions.
+ * So add an ACS quirk for below devices to isolate functions.
+ * SFxxx 1G NICs(em).
+ * RP1000/RP2000 10G NICs(sp).
+ */
+static int  pci_quirk_wangxun_nic_acs(struct pci_dev *dev, u16 acs_flags)
+{
+	switch (dev->device) {
+	case 0x0100 ... 0x010F:
+	case 0x1001:
+	case 0x2001:
+		return pci_acs_ctrl_enabled(acs_flags,
+			PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);
+	}
+
+	return false;
+}
+
 static const struct pci_dev_acs_enabled {
 	u16 vendor;
 	u16 device;
@@ -4980,6 +5000,8 @@ static const struct pci_dev_acs_enabled {
 	{ PCI_VENDOR_ID_NXP, 0x8d9b, pci_quirk_nxp_rp_acs },
 	/* Zhaoxin Root/Downstream Ports */
 	{ PCI_VENDOR_ID_ZHAOXIN, PCI_ANY_ID, pci_quirk_zhaoxin_pcie_ports_acs },
+	/* Wangxun nics */
+	{ PCI_VENDOR_ID_WANGXUN, PCI_ANY_ID, pci_quirk_wangxun_nic_acs },
 	{ 0 }
 };
 
diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
index b362d90eb9b0..bc8f484cdcf3 100644
--- a/include/linux/pci_ids.h
+++ b/include/linux/pci_ids.h
@@ -3012,6 +3012,8 @@
 #define PCI_DEVICE_ID_INTEL_VMD_9A0B	0x9a0b
 #define PCI_DEVICE_ID_INTEL_S21152BB	0xb152
 
+#define PCI_VENDOR_ID_WANGXUN		0x8088
+
 #define PCI_VENDOR_ID_SCALEMP		0x8686
 #define PCI_DEVICE_ID_SCALEMP_VSMP_CTL	0x1010
 
-- 
2.39.1

