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ACPI: Implement acpi_dma_configure

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On DT based systems, the of_dma_configure() API implements DMA
configuration for a given device. On ACPI systems an API equivalent to
of_dma_configure() is missing which implies that it is currently not
possible to set-up DMA operations for devices through the ACPI generic
kernel layer.

This patch fills the gap by introducing acpi_dma_configure/deconfigure()
calls that for now are just wrappers around arch_setup_dma_ops() and
arch_teardown_dma_ops() and also updates ACPI and PCI core code to use
the newly introduced acpi_dma_configure/acpi_dma_deconfigure functions.

Since acpi_dma_configure() is used to configure DMA operations, the
function initializes the dma/coherent_dma masks to sane default values
if the current masks are uninitialized (also to keep the default values
consistent with DT systems) to make sure the device has a complete
default DMA set-up.

The DMA range size passed to arch_setup_dma_ops() is sized according
to the device coherent_dma_mask (starting at address 0x0), mirroring the
DT probing path behaviour when a dma-ranges property is not provided
for the device being probed; this changes the current arch_setup_dma_ops()
call parameters in the ACPI probing case, but since arch_setup_dma_ops()
is a NOP on all architectures but ARM/ARM64 this patch does not change
the current kernel behaviour on them.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> [pci]
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Tomasz Nowicki <tn@semihalf.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Tomasz Nowicki <tn@semihalf.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Tomasz Nowicki <tn@semihalf.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Lorenzo Pieralisi 2016-11-21 10:01:39 +00:00 committed by Will Deacon
parent 778de07453
commit d760a1baf2
5 changed files with 50 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/acpi/glue.c
View File

@ -227,8 +227,7 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
attr = acpi_get_dma_attr(acpi_dev);
if (attr != DEV_DMA_NOT_SUPPORTED)
arch_setup_dma_ops(dev, 0, 0, NULL,
attr == DEV_DMA_COHERENT);
acpi_dma_configure(dev, attr);
acpi_physnode_link_name(physical_node_name, node_id);
retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
@ -251,6 +250,7 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
return 0;
err:
acpi_dma_deconfigure(dev);
ACPI_COMPANION_SET(dev, NULL);
put_device(dev);
put_device(&acpi_dev->dev);

40
drivers/acpi/scan.c
View File

@ -1370,6 +1370,46 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
return DEV_DMA_NON_COHERENT;
}
/**
* acpi_dma_configure - Set-up DMA configuration for the device.
* @dev: The pointer to the device
* @attr: device dma attributes
*/
void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
{
/*
* Set default coherent_dma_mask to 32 bit. Drivers are expected to
* setup the correct supported mask.
*/
if (!dev->coherent_dma_mask)
dev->coherent_dma_mask = DMA_BIT_MASK(32);
/*
* Set it to coherent_dma_mask by default if the architecture
* code has not set it.
*/
if (!dev->dma_mask)
dev->dma_mask = &dev->coherent_dma_mask;
/*
* Assume dma valid range starts at 0 and covers the whole
* coherent_dma_mask.
*/
arch_setup_dma_ops(dev, 0, dev->coherent_dma_mask + 1, NULL,
attr == DEV_DMA_COHERENT);
}
EXPORT_SYMBOL_GPL(acpi_dma_configure);
/**
* acpi_dma_deconfigure - Tear-down DMA configuration for the device.
* @dev: The pointer to the device
*/
void acpi_dma_deconfigure(struct device *dev)
{
arch_teardown_dma_ops(dev);
}
EXPORT_SYMBOL_GPL(acpi_dma_deconfigure);
static void acpi_init_coherency(struct acpi_device *adev)
{
unsigned long long cca = 0;

3
drivers/pci/probe.c
View File

@ -1738,8 +1738,7 @@ static void pci_dma_configure(struct pci_dev *dev)
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);
acpi_dma_configure(&dev->dev, attr);
}
pci_put_host_bridge_device(bridge);

2
include/acpi/acpi_bus.h
View File

@ -573,6 +573,8 @@ struct acpi_pci_root {
bool acpi_dma_supported(struct acpi_device *adev);
enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev);
void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr);
void acpi_dma_deconfigure(struct device *dev);
struct acpi_device *acpi_find_child_device(struct acpi_device *parent,
u64 address, bool check_children);

5
include/linux/acpi.h
View File

@ -765,6 +765,11 @@ static inline enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
return DEV_DMA_NOT_SUPPORTED;
}
static inline void acpi_dma_configure(struct device *dev,
enum dev_dma_attr attr) { }
static inline void acpi_dma_deconfigure(struct device *dev) { }
#define ACPI_PTR(_ptr) (NULL)
static inline void acpi_device_set_enumerated(struct acpi_device *adev)