ACPI: Implement acpi_dma_configure

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>

diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c
index 5ea5dc219f563702e5bad7141832af2861e9144a..f8d65647ea790dd161b07221b9be2bdead4447d0 100644 (file)
--- a/drivers/acpi/glue.c
+++ b/drivers/acpi/glue.c
@@ -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);

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 3d1856f1f4d03eb8c47e5e4043684d7b5b76b046..45b5710a0404a665bbbe763c34c6940323948d2f 100644 (file)
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -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;

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index ab002671fa60e14b83568a24d2cf504687f391f9..c29e07ad5a7f930f6ca88e58cfb2f25eae354417 100644 (file)
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -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);

diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index c1a524de67c5b8ab8f1c63ea77365dec085fcd91..4242c31ffaee3386b50d791915a8113423cf041d 100644 (file)
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -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);

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 996a29cdaccd63097933ebc0f88fa7e07f58b48f..8d15fc59719f21a107b4b423ea4ee2b8259385ec 100644 (file)
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -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)