From 29dbe1f0af88b4162d2b57e790db7a51ab061f35 Mon Sep 17 00:00:00 2001 From: "Suthikulpanit, Suravee" Date: Wed, 28 Oct 2015 15:50:54 -0700 Subject: [PATCH] PCI: ACPI: Add support for PCI device DMA coherency This patch adds support for setting up PCI device DMA coherency from ACPI _CCA object that should normally be specified in the DSDT node of its PCI host bridge. Signed-off-by: Suravee Suthikulpanit Acked-by: Bjorn Helgaas Reviewed-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki --- drivers/pci/probe.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index d35f83d80b15..064078e11017 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include "pci.h" @@ -1639,7 +1640,7 @@ static void pci_set_msi_domain(struct pci_dev *dev) * @dev: ptr to pci_dev struct of the PCI device * * Function to update PCI devices's DMA configuration using the same - * info from the OF node of host bridge's parent (if any). + * info from the OF node or ACPI node of host bridge's parent (if any). */ static void pci_dma_configure(struct pci_dev *dev) { @@ -1648,6 +1649,15 @@ static void pci_dma_configure(struct pci_dev *dev) if (IS_ENABLED(CONFIG_OF) && dev->dev.of_node) { if (bridge->parent) of_dma_configure(&dev->dev, bridge->parent->of_node); + } else if (has_acpi_companion(bridge)) { + struct acpi_device *adev = to_acpi_device_node(bridge->fwnode); + enum dev_dma_attr attr = acpi_get_dma_attr(adev); + + if (attr == DEV_DMA_NOT_SUPPORTED) + dev_warn(&dev->dev, "DMA not supported.\n"); + else + arch_setup_dma_ops(&dev->dev, 0, 0, NULL, + attr == DEV_DMA_COHERENT); } pci_put_host_bridge_device(bridge); -- 2.30.2