Hi everyone, On 2021/5/22 3:03, Rob Herring wrote:
On Thu, May 20, 2021 at 10:03 PM Wang Xingang <wangxingang5@xxxxxxxxxx> wrote:From: Xingang Wang <wangxingang5@xxxxxxxxxx> When booting with devicetree, the pci_request_acs() is called after the enumeration and initialization of PCI devices, thus the ACS is not enabled. And ACS should be enabled when IOMMU is detected for the PCI host bridge, so add check for IOMMU before probe of PCI host and call pci_request_acs() to make sure ACS will be enabled when enumerating PCI devices. Fixes: 6bf6c24720d33 ("iommu/of: Request ACS from the PCI core when configuring IOMMU linkage") Signed-off-by: Xingang Wang <wangxingang5@xxxxxxxxxx> --- drivers/iommu/of_iommu.c | 1 - drivers/pci/of.c | 8 +++++++- 2 files changed, 7 insertions(+), 2 deletions(-)Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
Ping, is this patch appropriate for mainline?
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index a9d2df001149..54a14da242cc 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -205,7 +205,6 @@ const struct iommu_ops *of_iommu_configure(struct device *dev, .np = master_np, }; - pci_request_acs(); err = pci_for_each_dma_alias(to_pci_dev(dev), of_pci_iommu_init, &info); } else { diff --git a/drivers/pci/of.c b/drivers/pci/of.c index da5b414d585a..2313c3f848b0 100644 --- a/drivers/pci/of.c +++ b/drivers/pci/of.c @@ -581,9 +581,15 @@ static int pci_parse_request_of_pci_ranges(struct device *dev, int devm_of_pci_bridge_init(struct device *dev, struct pci_host_bridge *bridge) { - if (!dev->of_node) + struct device_node *node = dev->of_node; + + if (!node) return 0; + /* Detect IOMMU and make sure ACS will be enabled */ + if (of_property_read_bool(node, "iommu-map")) + pci_request_acs(); + bridge->swizzle_irq = pci_common_swizzle; bridge->map_irq = of_irq_parse_and_map_pci; -- 2.19.1.
