[PATCH v3 0/3] PCI: Add a quirk to enable SVA for HiSilicon chip

[PATCH v3 0/3] PCI: Add a quirk to enable SVA for HiSilicon chip

[Zhangfei Gao]

HiSilicon KunPeng920 and KunPeng930 have devices appear as PCI but are
actually on the AMBA bus. These fake PCI devices have PASID capability
though not supporting TLP.

Add a quirk to set pasid_no_tlp and dma-can-stall for these devices.

v3:
Rebase to Linux 5.12-rc1
Change commit msg adding:
Property dma-can-stall depends on patchset
https://lore.kernel.org/linux-iommu/20210302092644.2553014-1-jean-philippe@linaro.org/

By the way the patchset can directly applied on 5.12-rc1 and build successfully though
without the dependent patchset.

v2:
Add a new pci_dev bit: pasid_no_tlp, suggested by Bjorn 
"Apparently these devices have a PASID capability.  I think you should
add a new pci_dev bit that is specific to this idea of "PASID works
without TLP prefixes" and then change pci_enable_pasid() to look at
that bit as well as eetlp_prefix_path."
https://lore.kernel.org/linux-pci/20210112170230.GA1838341@bjorn-Precision-5520/

Zhangfei Gao (3):
  PCI: PASID can be enabled without TLP prefix
  PCI: Add a quirk to set pasid_no_tlp for HiSilicon chips
  PCI: Set dma-can-stall for HiSilicon chips

 drivers/pci/ats.c    |  2 +-
 drivers/pci/quirks.c | 27 +++++++++++++++++++++++++++
 include/linux/pci.h  |  1 +
 3 files changed, 29 insertions(+), 1 deletion(-)

-- 
2.9.5

[PATCH v3 1/3] PCI: PASID can be enabled without TLP prefix

[Zhangfei Gao]

A PASID-like feature is implemented on AMBA without using TLP prefixes
and these devices have PASID capability though not supporting TLP.
Adding a pasid_no_tlp bit for "PASID works without TLP prefixes" and
pci_enable_pasid() checks pasid_no_tlp as well as eetlp_prefix_path.

Suggested-by: Bjorn Helgaas <helgaas@kernel.org>
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
---
 drivers/pci/ats.c   | 2 +-
 include/linux/pci.h | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index 793d381..88f981b 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -380,7 +380,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
 	if (WARN_ON(pdev->pasid_enabled))
 		return -EBUSY;
 
-	if (!pdev->eetlp_prefix_path)
+	if (!pdev->eetlp_prefix_path && !pdev->pasid_no_tlp)
 		return -EINVAL;
 
 	if (!pasid)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 86c799c..1daa943 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -388,6 +388,7 @@ struct pci_dev {
 					   supported from root to here */
 	u16		l1ss;		/* L1SS Capability pointer */
 #endif
+	unsigned int	pasid_no_tlp:1;		/* PASID works without TLP Prefix */
 	unsigned int	eetlp_prefix_path:1;	/* End-to-End TLP Prefix */
 
 	pci_channel_state_t error_state;	/* Current connectivity state */
-- 
2.9.5

[PATCH v3 2/3] PCI: Add a quirk to set pasid_no_tlp for HiSilicon chips

[Zhangfei Gao]

HiSilicon KunPeng920 and KunPeng930 have devices appear as PCI but are
actually on the AMBA bus. These fake PCI devices have PASID capability
though not supporting TLP.

Add a quirk to set pasid_no_tlp for these devices.

Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com>
---
 drivers/pci/quirks.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 653660e..873d27f 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -1825,6 +1825,20 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_E7525_MCH,	quir
 
 DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_VENDOR_ID_HUAWEI, 0x1610, PCI_CLASS_BRIDGE_PCI, 8, quirk_pcie_mch);
 
+static void quirk_huawei_pcie_sva(struct pci_dev *pdev)
+{
+	if (pdev->revision != 0x21 && pdev->revision != 0x30)
+		return;
+
+	pdev->pasid_no_tlp = 1;
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa250, quirk_huawei_pcie_sva);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa251, quirk_huawei_pcie_sva);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa255, quirk_huawei_pcie_sva);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa256, quirk_huawei_pcie_sva);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa258, quirk_huawei_pcie_sva);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa259, quirk_huawei_pcie_sva);
+
 /*
  * It's possible for the MSI to get corrupted if SHPC and ACPI are used
  * together on certain PXH-based systems.
-- 
2.9.5

[PATCH v3 3/3] PCI: Set dma-can-stall for HiSilicon chips

[Zhangfei Gao]

HiSilicon KunPeng920 and KunPeng930 have devices appear as PCI but are
actually on the AMBA bus. These fake PCI devices can support SVA via
SMMU stall feature, by setting dma-can-stall for ACPI platforms.

Property dma-can-stall depends on patchset
https://lore.kernel.org/linux-iommu/20210302092644.2553014-1-jean-philippe@linaro.org/

Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com>
---
 drivers/pci/quirks.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 873d27f..b866cdf 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -1827,10 +1827,23 @@ DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_VENDOR_ID_HUAWEI, 0x1610, PCI_CLASS_BRIDGE_PCI
 
 static void quirk_huawei_pcie_sva(struct pci_dev *pdev)
 {
+	struct property_entry properties[] = {
+		PROPERTY_ENTRY_BOOL("dma-can-stall"),
+		{},
+	};
+
 	if (pdev->revision != 0x21 && pdev->revision != 0x30)
 		return;
 
 	pdev->pasid_no_tlp = 1;
+
+	/*
+	 * Set the dma-can-stall property on ACPI platforms. Device tree
+	 * can set it directly.
+	 */
+	if (!pdev->dev.of_node &&
+	    device_add_properties(&pdev->dev, properties))
+		pci_warn(pdev, "could not add stall property");
 }
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa250, quirk_huawei_pcie_sva);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa251, quirk_huawei_pcie_sva);
-- 
2.9.5