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 <Suravee.Suthikulpanit@amd.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Suthikulpanit, Suravee 2015-10-28 15:50:54 -07:00 committed by Rafael J. Wysocki
parent 50230713b6
commit 29dbe1f0af

View File

@ -13,6 +13,7 @@
#include <linux/module.h>
#include <linux/cpumask.h>
#include <linux/pci-aspm.h>
#include <linux/acpi.h>
#include <asm-generic/pci-bridge.h>
#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);